A method and system for monitoring ammonia content in a flue gas denitration system

Abstract

The present invention relates to the technical field of gas detection, and particularly relates to a method and system for monitoring the ammonia content in a flue gas denitration system. First, based on the similar characteristics of the ammonia content and consumption between monitoring points in the flue of the flue gas denitration system, the ammonia consumption of each monitoring point is determined; then, based on the periodic characteristics of the ammonia content after the filter bag is cleaned and replaced and the similar characteristics of the ammonia content of adjacent monitoring points, the ammonia consumption fitting difference is determined; thus, by combining the periodic similarity characteristics and the adjacent similarity characteristics, a more accurate fitting ammonia consumption of each monitoring point at the current sampling moment is determined, making the accuracy of monitoring the ammonia content in the flue gas denitration system based on the fitting ammonia consumption higher.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection, and particularly to a method and a system for monitoring the ammonia content in a flue gas denitrification system. Background Art

[0002] The increasing requirements for the treatment of industrial flue gas have led to the widespread application of catalytic filter bag denitrification systems. As an efficient flue gas treatment technology, its core lies in using catalysts to promote the reduction reaction of ammonia and nitrogen oxides, converting nitrogen oxides into nitrogen and water. In order to better control the denitrification process and adjust to minimize the residual ammonia after conversion, it is necessary to continuously regulate the ammonia content. Therefore, the monitoring of ammonia content is a key link in the operation of catalytic filter bag denitrification systems. It not only helps to accurately control the ammonia injection volume to ensure the best efficiency of the denitrification reaction, but also effectively prevents secondary pollution caused by ammonia escape. It can continuously monitor the ammonia concentration at various locations in the flue gas, providing accurate data support for the denitrification process.

[0003] Currently, Tunable Diode Laser Absorption Spectroscopy (TDLAS) technology has become the mainstream choice for real-time monitoring of ammonia content. Its main measurement methods include in-situ laser method and extraction method. Among them, because the analysis system of the extraction method is far from the sampling system, resulting in a certain lag in measurement, it is less commonly used when real-time monitoring is required. The commonly used method is the in-situ laser method. This technology first emits a laser beam, and then by comparing the difference between the laser intensity received by the receiver and the original laser intensity, during this process, ammonia will absorb the laser signal, causing the laser intensity to decrease. Based on this characteristic, relevant data in the flue gas are directly collected at each monitoring point, and then data processing is carried out to finally obtain the ammonia content at each monitoring point. The in-situ laser method measures directly in the flue duct. In order to accurately monitor the ammonia content in the flue duct, multiple sets of sensors need to be set. The environment inside the flue duct is relatively complex, and some soot will occasionally accumulate on the probe, resulting in the laser signal monitored by the probe being scattered and reduced, causing the monitored value to deviate. Then, as the flue gas flows, this soot is carried away by the airflow, resulting in the probe monitoring being relatively accurate again. The optical signal monitored by the receiving probe is sometimes accurate and sometimes inaccurate, and the measurement accuracy is seriously affected by the soot; that is, the accuracy of the existing technology for measuring the final ammonia content in the flue duct of a flue gas denitrification system using the in-situ laser method is relatively low. Summary of the Invention

[0004] In order to solve the technical problem that the accuracy of the existing technology for measuring the final ammonia content in the flue duct of a flue gas denitrification system using the in-situ laser method is relatively low, the purpose of this application is to provide a method and a system for monitoring the ammonia content in a flue gas denitrification system. The specific technical solutions adopted are as follows:

[0005] The first aspect of the present application provides a method for monitoring the ammonia content in a flue gas denitrification system, including:

[0006] In the flue of the flue gas denitrification system, collect the unpurified ammonia content before purification and the initial ammonia content after purification at each monitoring point at each sampling moment; obtain the adjacent points adjacent to each monitoring point among all monitoring points;

[0007] At each sampling moment, determine the ammonia consumption of each monitoring point according to the initial ammonia content of each monitoring point, the unpurified ammonia content of each adjacent point, and the relative distance; determine at least two cycle time periods among all sampling moments according to the time series differential change cycle fluctuation of the ammonia consumption of each monitoring point;

[0008] Calculate the ammonia consumption deviation value between each monitoring point and each adjacent point at each sampling moment in each cycle time period; determine the ammonia consumption fitting difference between each monitoring point and each adjacent point within the current cycle time period according to the overall similarity of the ammonia consumption deviation values between the current cycle time period and other cycle time periods, and the ammonia consumption deviation values corresponding to each sampling moment in the current cycle time period;

[0009] Determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the historical ammonia consumption cycle change of each monitoring point and the overall numerical size of the ammonia consumption within the current cycle time period; determine the fitted ammonia consumption of each monitoring point at the current sampling moment according to the reference ammonia consumption of each monitoring point at the current sampling moment and the corresponding ammonia consumption fitting differences;

[0010] Monitor the ammonia content in the flue gas denitrification system according to the fitted ammonia consumption.

[0011] Further, the process of obtaining the ammonia consumption includes:

[0012] Successively take each monitoring point as the target point; obtain all adjacent monitoring points within the preset neighborhood range of the target point;

[0013] At each sampling moment, perform negative correlation normalization on the distance from each adjacent monitoring point to the target point to determine the distance weight of each adjacent monitoring point; determine the unpurified ammonia weighted value of each adjacent monitoring point according to the product of the unpurified ammonia content of each adjacent monitoring point and the distance weight; determine the average unpurified ammonia content of the target point according to the cumulative value of the unpurified ammonia weighted values of all adjacent monitoring points;

[0014] Take the difference between the average unpurified ammonia content and the initial ammonia content of the target point as the ammonia consumption of the target point.

[0015] Further, the process of obtaining the cycle time period includes:

[0016] After arranging the ammonia consumption of each monitoring point in chronological order, an ammonia consumption time series is obtained; the ammonia consumption time series is subjected to difference calculation to obtain an ammonia consumption difference series; the moment corresponding to the maximum value point in the ammonia consumption difference series is used as the periodic interval moment; all sampling moments are divided into at least two periodic time periods at intervals of the periodic interval moment.

[0017] Furthermore, the process of obtaining the ammonia consumption fitting difference includes:

[0018] For each monitoring point and each neighboring point, according to the deviation sum of ammonia consumption deviation values and the deviation situation of the change rate of ammonia consumption deviation values between the sampling moments of each sampling moment in the current periodic time period and the sampling moments at the corresponding periodic positions of each historical periodic time period, the difference confidence level at each sampling moment in the current periodic time period is determined;

[0019] According to the product of the normalized value of the difference confidence level and the ammonia consumption deviation value at each sampling moment in the current periodic time period, the weighted ammonia consumption difference at each sampling moment in the current periodic time period is determined; according to the accumulated value of the weighted ammonia consumption differences at all sampling moments in the current periodic time period, the ammonia consumption fitting difference between each monitoring point and each neighboring point within the current periodic time period is determined.

[0020] Furthermore, the process of obtaining the difference confidence level includes:

[0021] For each monitoring point and each neighboring point, according to the absolute value of the difference between the ammonia consumption deviation value of each sampling moment in the current periodic time period and the ammonia consumption deviation value of the sampling moment at the same periodic position in each historical periodic time period, the corresponding ammonia consumption period difference value between the current periodic time period and each historical periodic time period at each sampling moment is determined;

[0022] According to the overall deviation of the change rates of the ammonia consumption deviation values at each sampling moment between the current periodic time period and each historical periodic time period, the overall periodic difference between the current periodic time period and each historical periodic time period is determined;

[0023] The product of the normalized value of the overall periodic difference and the ammonia consumption period difference value is used as the weighted period difference value between the current periodic time period and each historical periodic time period at each sampling moment; the accumulated value of all the weighted period difference values corresponding to each sampling moment in the current periodic time period is subjected to a negative correlation mapping to determine the difference confidence level at each sampling moment in the current periodic time period.

[0024] Furthermore, the process of obtaining the overall periodic difference includes:

[0025] The difference between the ammonia consumption deviation value at the next sampling moment corresponding to each sampling moment and the ammonia consumption deviation value at the previous sampling moment is used as the ammonia consumption difference change rate; after arranging the ammonia consumption change rates at all sampling moments in each cycle time period in chronological order, an ammonia consumption change rate sequence for each cycle time period is determined; the DTW distance between the two ammonia consumption change rate sequences corresponding to the current cycle time period and each historical cycle time period is used as the corresponding overall cycle difference.

[0026] Further, the process of obtaining the reference ammonia consumption includes:

[0027] Predict the ammonia consumption in each historical cycle time period corresponding to each monitoring point through the SARIMA model algorithm to determine the predicted ammonia consumption of each monitoring point at the current moment;

[0028] The sampling moment corresponding to the same cycle position of the current sampling moment in each historical cycle time period is used as the comparison sampling moment; according to the mean value of all ammonia consumption amounts corresponding to each monitoring point at the current sampling moment and all comparison sampling moments, the overall ammonia consumption of each monitoring point at the current sampling moment is determined;

[0029] According to the mean value of the predicted ammonia consumption and the overall ammonia consumption, the reference ammonia consumption of each monitoring point at the current sampling moment is determined.

[0030] Further, the process of obtaining the fitted ammonia consumption includes:

[0031] The sum value between the reference ammonia consumption of each neighboring point corresponding to each monitoring point at the current sampling moment and the ammonia consumption fitting difference is used as the relative ammonia consumption of each neighboring point corresponding to each monitoring point; according to the mean value of the relative ammonia consumption of all neighboring points corresponding to each monitoring point, the fitted ammonia consumption of each monitoring point at the current sampling moment is determined.

[0032] Further, the process of monitoring the ammonia content in the flue gas denitration system according to the fitted ammonia consumption includes:

[0033] The difference between the unpurified ammonia average content and the fitted ammonia consumption is used to determine the final ammonia content of each monitoring point.

[0034] In a second aspect, the present application provides a monitoring system for ammonia content in a flue gas denitration system, and the system includes:

[0035] A data acquisition and preprocessing module, which is used to collect the unpurified ammonia content before purification and the initial ammonia content after purification at each sampling moment for each monitoring point in the flue of the flue gas denitration system; and obtain adjacent points adjacent to each monitoring point among all monitoring points;

[0036] A first determination module, which is used to determine the ammonia consumption of each monitoring point at each sampling moment according to the initial ammonia content of each monitoring point, the unpurified ammonia content of each adjacent point, and the relative distance; and determine at least two periodic time periods among all sampling moments according to the periodic differential change cycle fluctuation of the ammonia consumption of each monitoring point;

[0037] A second determination module, which is used to calculate the ammonia consumption deviation value between each monitoring point and each adjacent point at each sampling moment in each periodic time period; and determine the ammonia consumption fitting difference between each monitoring point and each adjacent point within the current periodic time period according to the overall similarity of the ammonia consumption deviation values between the current periodic time period and other periodic time periods, and the ammonia consumption deviation values corresponding to each sampling moment in the current periodic time period;

[0038] A third determination module, which is used to determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the historical periodic change of the ammonia consumption of each monitoring point and the overall numerical size of the ammonia consumption within the current periodic time period; and determine the fitted ammonia consumption of each monitoring point at the current sampling moment according to the reference ammonia consumption of each monitoring point at the current sampling moment and the corresponding ammonia consumption fitting differences;

[0039] An ammonia content monitoring module, which is used to monitor the ammonia content of the flue gas denitration system according to the fitted ammonia consumption.

[0040] In a third aspect, the present application provides a computer device, including a memory and a processor. The memory is used to store computer program code, and the processor is used to call and run the computer program code from the memory to execute the method according to the first aspect or any embodiment of the first aspect of the present application.

[0041] In a fourth aspect, the present application provides a computer program product, which includes computer program code, and when the computer program code is executed, it is used to execute the method according to the first aspect or any embodiment of the first aspect of the present application.

[0042] In a fifth aspect, the present application provides a computer-readable storage medium, which stores computer program code, and when the computer program code is executed, it is used to execute the method according to the first aspect or any embodiment of the first aspect of the present application.

[0043] The present application has the following beneficial effects:

[0044] When monitoring the ammonia content in the prior art, since various monitoring sensors are directly installed in the flue, they are vulnerable to the influence of soot, resulting in unstable optical signals detected by the receiving probe and seriously affecting the measurement accuracy. In addition, due to the influence of soot, when measuring the final ammonia content by the in-situ laser method, the accuracy of the optical signal fluctuates, sometimes accurate and sometimes inaccurate, which limits its reliability in practical applications.

[0045] First, the unpurified ammonia content at each point is vaguely described by the ammonia content monitored in the unpurified flue gas in the nearby area. Then, the ammonia content before and after purification at the same monitoring point is compared and analyzed to calculate its purification consumption; at the same time, a single monitoring point is analyzed to examine the periodic change law of the purification consumption in its historical time series. After that, the difference in ammonia consumption between the target monitoring point and its surrounding monitoring points in the past time series is analyzed; at the same time, according to the unity of the difference in ammonia consumption between the neighboring monitoring points and the target monitoring point in the past time series, its confidence level is constructed; then, according to the difference in ammonia consumption between adjacent monitoring points, combined with the corresponding confidence level, the fitting difference in ammonia consumption between many neighboring monitoring points and the target monitoring point at the target moment is constructed. Finally, first, according to the periodic law of each monitoring point, the predicted ammonia consumption at the target moment is preliminarily predicted, and combined with the corresponding monitored ammonia consumption, the reference ammonia consumption at the target moment is obtained; then, combined with the reference ammonia consumption of each neighboring monitoring point and the corresponding fitting difference, the fitting ammonia consumption of the target monitoring point is constructed; finally, according to the unpurified ammonia content of the target monitoring point at the target moment and the corresponding fitting ammonia consumption, the final ammonia content corresponding to the target moment is obtained. Based on this, the error in ammonia content monitoring caused by soot interference in the flue gas can be avoided. At the same time, the stability and accuracy of ammonia monitoring in the flue can be effectively improved, and it is helpful to optimize the ammonia supply process during denitrification and improve the working efficiency of the denitrification system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0047] Figure 1 It is a flowchart of a method for monitoring the ammonia content of a flue gas denitrification system provided by an embodiment of the present invention;

[0048] Figure 2 It is a structural diagram of a system for monitoring the ammonia content of a flue gas denitrification system provided by an embodiment of the present invention;

[0049] Figure 3 Schematic diagram of a computer device structure provided by an embodiment of the present invention. Specific implementation manners

[0050] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following combines the accompanying drawings and preferred embodiments to detail the specific implementation manners, structures, features and effects of a method and system for monitoring ammonia content in a flue gas denitration system proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment, and specific features, structures or characteristics in one or more embodiments can be combined in any suitable form. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0052] The following specifically describes the specific solutions of a method and system for monitoring ammonia content in a flue gas denitration system provided by the present invention with reference to the accompanying drawings.

[0053] An embodiment of the present application provides a method for monitoring ammonia content in a flue gas denitration system. Please refer to Figure 1 , which shows a flowchart of a method for monitoring ammonia content in a flue gas denitration system provided by an embodiment of the present invention. The method includes:

[0054] Step S101: In the flue of the flue gas denitration system, collect the unpurified ammonia content before purification and the initial ammonia content after purification at each monitoring point at each sampling moment; obtain adjacent points adjacent to each monitoring point among all monitoring points.

[0055] A quantum cascade laser is installed as a light source at each monitoring point position in the flue of the flue gas denitration system, and wavelength modulation spectroscopy technology is used as the monitoring unit to monitor and receive the laser signal at each sampling moment in real time. In a specific implementation manner of the embodiment of the present invention, the Topsoe catalytic denitration filter bag is selected for the flue gas denitration system, the monitoring frequency is set to monitor once per second, and the time interval between corresponding adjacent sampling moments is 1 second; and the time range of the sampling moment is set to the current moment and the previous six months, which can be adjusted according to the specific implementation environment.

[0056] In addition, the wavelength of the laser beam emitted by the quantum cascade laser is the wavelength corresponding to the characteristic absorption peak of ammonia gas, which is used to monitor the content of each gas in the flue gas at the corresponding position. After the corresponding laser signal is collected, it is processed by algorithms such as least squares fitting or neural network to obtain the corresponding gas content. It should be noted that the specific process of monitoring the ammonia content by means of the laser signal of the quantum cascade laser refers to the performance test research technology of the high-precision on-line flue gas ammonia analyzer based on quantum cascade laser, which belongs to the technical means in the prior art and will not be further elaborated here.

[0057] In a specific implementation manner of the embodiment of the present invention, a monitoring point is set every 0.1 meters in the flue of the flue gas denitration system, and the ammonia content inside and outside the filter membrane of the Topsoe catalytic denitration filter bag is monitored through the monitoring points. The corresponding ammonia content inside is the initial ammonia content after purification, and the ammonia content outside is the unpurified ammonia content. It should be noted that the embodiment of the present invention is not limited to the measurement of the final ammonia content, and the gas types can be adjusted by adjusting the wavelength of the laser beam emitted by the quantum cascade laser, such as nitrogen gas and nitrogen oxides, etc., which will not be further elaborated here.

[0058] In a specific implementation manner of the embodiment of the present invention, other monitoring points with an Euclidean distance less than 1 meter from each monitoring point are used as the neighboring points of each monitoring point, and the range size can be adjusted according to the specific implementation environment, which will not be further elaborated here.

[0059] Step S102: At each sampling moment, determine the ammonia consumption of each monitoring point according to the initial ammonia content of each monitoring point, the unpurified ammonia content of each neighboring point, and the relative distance; determine at least two periodic time periods among all sampling moments according to the periodic differential change cycle fluctuation situation of the ammonia consumption of each monitoring point.

[0060] In the catalytic filter bag denitrification system, it mainly filters soot through the filter bag and catalyzes the reaction between ammonia and nitrogen oxides. However, with the progress of filtration denitrification, the filter screen will be affected by the soot left by filtration, resulting in a decrease in its purification and denitrification efficiency. To ensure the smooth progress of the entire catalytic denitrification process, the filter bag will be cleaned or replaced regularly. This causes the consumption of ammonia passing through the filter screen (including catalyst) at each monitoring point to change periodically. In addition, since the flue gas is not divided in the pipeline before entering the dust removal and denitrification filter bag, it will mix and diffuse randomly. Therefore, before these flue gases are purified, the contents of each component in the flue gas are similar or even the same in some adjacent areas; this results in similar ammonia contents in the flue gas before purification in this area; at the same time, it can also be concluded that the loss degree of the filter screen in this area is similar, and its dust removal and denitrification effect on the flue gas is also similar. Based on this, the difference in ammonia content inside and outside the filter screen at each monitoring point can be obtained. Combining the ammonia content before its dust removal and purification, the ammonia content monitoring at the corresponding position can be completed.

[0061] Preferably, in some possible implementation manners of the embodiments of the present invention, the process of obtaining the ammonia consumption includes:

[0062] Successively take each monitoring point as the target point; obtain all adjacent monitoring points within the preset neighborhood range of the target point;

[0063] At each sampling moment, perform negative correlation normalization on the distances from each adjacent monitoring point to the target point to determine the distance weight of each adjacent monitoring point; determine the unpurified ammonia weighted value of each adjacent monitoring point according to the product of the unpurified ammonia content of each adjacent monitoring point and the distance weight; determine the average unpurified ammonia content of the target point according to the cumulative value of the unpurified ammonia weighted values of all adjacent monitoring points; take the difference between the average unpurified ammonia content and the initial ammonia content of the target point as the ammonia consumption of the target point.

[0064] Because ammonia flows in the flue, its flow through the flue and the filter screen of the filter bag is relatively slow, resulting in the slow diffusion of each component inside it, so that in a small area, the contents of each component in the flue gas are relatively close. Thus, the ammonia contents at several monitoring points near each monitoring point are relatively the same; therefore, the unpurified ammonia content of the monitoring point at a certain moment can be approximately described based on the unpurified ammonia content corresponding to the monitoring points adjacent to each monitoring point; further, based on the described unpurified ammonia content and the initial ammonia content after purification, the corresponding ammonia consumption can be determined. For each adjacent point, the closer it is to the target point, the higher the credibility of the ammonia content of this adjacent point. Therefore, the negative correlation normalization value of the distance is used as the weight for weighting to obtain a more accurate average unpurified ammonia content.

[0065] In a specific implementation manner of the embodiment of the present invention, the acquisition process of ammonia consumption is expressed by the formula: ; where is the ammonia consumption of the th monitoring point at the th sampling moment; is the number of neighboring points of the th monitoring point; is the Euclidean distance between the th monitoring point and the corresponding th neighboring point; is the unpurified ammonia content of the th neighboring point of the th monitoring point at the th sampling moment; is the initial ammonia content of the th monitoring point at the th sampling moment; is the softmax normalization function, and its unique normalization method can make the sum of all the normalized values equal to 1, making the subsequent accumulation operation more suitable for the scenario; is the distance weight of the th neighboring point of the th monitoring point; is the unpurified ammonia weighted value of the th neighboring point of the th monitoring point at the th sampling moment; is the average unpurified ammonia content of the th monitoring point at the th sampling moment.

[0066] When denitrifying and dedusting the lime kiln flue gas, as time goes by, soot will continuously accumulate on the filter screen, making the purification efficiency of the subsequent flue gas passing through the filter bag gradually decrease. In order to ensure the normal operation of the filter bag, it is necessary to regularly replace and clean the filter screen and filter bag, and the purification efficiency at the corresponding position will return to the initial efficiency after replacement. This results in a periodic change in the purification efficiency of each monitoring point.

[0067] Preferably, in some possible implementation manners of the embodiment of the present invention, the acquisition process of the periodic time period includes:

[0068] After arranging the ammonia consumption at each monitoring point in chronological order, an ammonia consumption time series is obtained; the ammonia consumption time series is subjected to difference calculation to obtain an ammonia consumption difference series; the moment corresponding to the maximum value point in the ammonia consumption difference series is used as the periodic interval moment; all sampling moments are divided into at least two periodic time periods at intervals of the periodic interval moment. Since the purification efficiency will suddenly increase each time the filter is replaced, the maximum value point in the ammonia consumption difference series is used as the division point. Specifically, the next moment after the periodic interval moment is used as the start moment of the new periodic time period, and the periodic interval moment is used as the end moment of the old periodic time period; it can also be adjusted by oneself.

[0069] Step S103: Calculate the ammonia consumption deviation value between each monitoring point and each neighboring point at each sampling moment in each periodic time period; determine the ammonia consumption fitting difference between each monitoring point and each neighboring point within the current periodic time period according to the overall similarity of the ammonia consumption deviation values between the current periodic time period and other periodic time periods, and the ammonia consumption deviation values corresponding to each sampling moment in the current periodic time period.

[0070] Although the flue gas components at each monitoring point, i.e., the neighboring points, are similar before denitrification, due to differences in the production and cleaning of the filters at different monitoring points, their purification efficiencies are different, and this difference is difficult to change during the flue gas denitrification and dust removal process. Therefore, within the same cycle, this difference will be retained. Therefore, first calculate the ammonia consumption deviation value between each monitoring point and each neighboring point at each sampling moment in each periodic time period. In a specific implementation manner of the embodiment of the present invention, the acquisition process of the ammonia consumption deviation value is expressed by the formula: ; where is the ammonia consumption deviation value between the th monitoring point and the corresponding th neighboring point at the th sampling moment in the th periodic time period; is the ammonia consumption of the th monitoring point at the th sampling moment in the th periodic time period; is the ammonia consumption of the th neighboring point corresponding to the th monitoring point at the th sampling moment in the th periodic time period; Further calculate the ammonia consumption deviation value between each monitoring point and its corresponding neighboring points at each sampling moment in each periodic time period.

[0071] When the filter screen is in use, as the flue gas is filtered, the soot will be left behind; at the same time, the filter screen will be replaced and cleaned every once in a while. Therefore, in the entire time sequence, the purification efficiency of the filter screen in each cycle is the same. As analyzed above, as the filter screen is used, it will gradually become blocked at each monitoring point. Since the flue gas components at two adjacent monitoring points are always similar, the blocking speeds at the two monitoring points are similar. Therefore, the changes in the purification efficiency at the two monitoring points at each moment are consistent, resulting in a similar difference in the purification efficiency between two adjacent monitoring points within the same cycle. Similarly, the purification efficiency at the same moment in the past cycle should also be consistent. If the deviation is too large, it means it is not credible. Therefore, the confidence level can be measured based on this characteristic.

[0072] Preferably, in some possible implementation manners of the embodiments of the present invention, the obtaining process of the ammonia consumption fitting difference includes:

[0073] For each monitoring point and each adjacent point, according to the deviation sum of the ammonia consumption deviation value and the deviation situation of the change rate of the ammonia consumption deviation value between each sampling moment in the current cycle time period and the sampling moments at the corresponding cycle positions in each historical cycle time period, determine the difference confidence level at each sampling moment in the current cycle time period. In a specific implementation manner of the embodiments of the present invention, the obtaining process of the difference confidence level includes:

[0074] For each monitoring point and each adjacent point, according to the absolute value of the difference between the ammonia consumption deviation value at each sampling moment in the current cycle time period and the ammonia consumption deviation value at the sampling moment at the same cycle position in each historical cycle time period, determine the corresponding ammonia consumption cycle difference value between the current cycle time period and each historical cycle time period at each sampling moment. The cycle position refers to the index value of the corresponding sampling moment in the corresponding cycle time period. The same cycle position means the same index value; when there is no corresponding cycle position in the corresponding historical cycle time period, set the corresponding ammonia consumption cycle difference value to 0 to ensure the integrity of the embodiment; the smaller the ammonia consumption cycle difference value, the more similar the ammonia consumption characteristics at the corresponding sampling moment, and the greater the corresponding confidence level.

[0075] The ammonia consumption cycle difference value analyzes the corresponding confidence level in the local numerical dimension, and each ammonia consumption cycle difference value only corresponds to one cycle. Therefore, it is necessary to further analyze in the overall dimension; based on this, the embodiments of the present invention further determine the overall cycle difference between the current cycle time period and each historical cycle time period according to the overall deviation of the change rate of the ammonia consumption deviation values at each sampling moment between the current cycle time period and each historical cycle time period; in some possible implementation manners of the embodiments of the present invention, the obtaining process of the overall cycle difference includes:

[0076] The difference between the ammonia consumption deviation value at the next sampling moment corresponding to each sampling moment and the ammonia consumption deviation value at the previous sampling moment is used as the ammonia consumption difference change rate; after arranging the ammonia consumption change rates at all sampling moments in each periodic time period in chronological order, an ammonia consumption change rate sequence for each periodic time period is determined; the DTW distance between the two ammonia consumption change rate sequences corresponding to the current periodic time period and each historical periodic time period is used as the corresponding overall periodic difference. Based on the characteristic that the changes in the purification efficiency of adjacent monitoring points usually tend to be consistent, the ammonia consumption change rates between periodic time periods should maintain the same trend. Therefore, the larger the DTW distance between the ammonia consumption change rate sequences of two periodic time periods calculated by the dynamic time warping algorithm, that is, the smaller the overall periodic difference, the less it conforms to the periodic characteristic, and the corresponding confidence level should be smaller. It should be noted that the dynamic time warping algorithm is a well-known technical means in the art and will not be further elaborated here.

[0077] Therefore, further integrating the representation of the confidence level locally and globally, further multiplying the normalized value of the overall periodic difference by the ammonia consumption periodic difference value as the weighted periodic difference value between the current periodic time period and each historical periodic time period at each sampling moment; performing a negative correlation mapping on the cumulative value of all weighted periodic difference values corresponding to each sampling moment in the current periodic time period to determine the difference confidence level at each sampling moment in the current periodic time period. By multiplying, the confidence level is represented locally and globally, and based on the obtained weighted periodic difference values, the weighted periodic difference values of each historical periodic time period are integrated. Considering that the greater the difference between periods, the less it conforms to the periodic characteristic, and the corresponding confidence level should be smaller. Therefore, after accumulating all weighted periodic difference values and then performing a negative correlation mapping, the confidence level required in the embodiments of the present invention is determined.

[0078] In a specific implementation manner of the embodiments of the present invention, the process of obtaining the difference confidence level is expressed by the formula: ; where is the difference confidence level at the th monitoring point and the th adjacent point at the th sampling moment in the current periodic time period; is the number of historical periodic time periods, that is, the number of other periodic time periods outside the current periodic time period, and the current periodic time period is the periodic time period where the current moment is located; is the th monitoring point and the The overall cycle difference between the current cycle time period corresponding to each neighboring point and each historical cycle time period, that is, the DTW distance between the two ammonia consumption change rate sequences corresponding to the current cycle time period and each historical cycle time period; is the ammonia consumption deviation value of the th monitoring point and the th neighboring point at the th sampling moment in the current cycle time period; is the ammonia consumption deviation value of the th monitoring point and the th neighboring point at the th sampling moment in the th historical cycle time period, with the same index value c to ensure the same cycle position; is the softmax normalization function, which has the same purpose as the above softmax normalization function and is used to cooperate with the accumulation to make it more suitable for the scenario;

[0079] After obtaining the difference confidence level, considering that the confidence levels of the ammonia consumption differences between the two monitoring points at different times are different, the confidence level is used to weight the ammonia consumption deviation. Further, according to the product of the normalized value of the difference confidence level and the ammonia consumption deviation value at each sampling moment in the current cycle time period, the weighted ammonia consumption difference at each sampling moment in the current cycle time period is determined; according to the accumulated value of the weighted ammonia consumption differences at all sampling moments in the current cycle time period, the ammonia consumption fitting difference between each monitoring point and each neighboring point within the current cycle time period is determined; thereby comprehensively characterizing the ammonia consumption fitting difference between each monitoring point and each neighboring point in the dimension of the entire cycle, making the analysis result more robust.

[0080] In a specific implementation manner of the embodiment of the present invention, the process of obtaining the ammonia consumption fitting difference is expressed by the formula: ; where is the ammonia consumption fitting difference between the th monitoring point and the th neighboring point within the current cycle time period; is the number of sampling moments within the current cycle time period; is the difference confidence level of the th monitoring point and the th neighboring point at the th sampling moment in the current cycle time period; is the The ammonia consumption deviation value of the th sampling moment of a neighboring point in the current cycle time period; is the th monitoring point and the th neighboring point at the th sampling moment in the current cycle time period; the weighted ammonia consumption difference; is the softmax normalization function.

[0081] Step S104: Determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the historical periodic change of ammonia consumption of each monitoring point and the overall value of ammonia consumption in the current cycle time period; determine the fitted ammonia consumption of each monitoring point at the current sampling moment according to the reference ammonia consumption of each monitoring point at the current sampling moment and the corresponding ammonia consumption fitting differences.

[0082] During the use of the filter bag filter screen, soot gradually deposits, resulting in a gradual decrease in the dust removal and denitrification efficiency at the corresponding position, and then due to regular cleaning, the corresponding denitrification efficiency shows a periodic recovery, which leads to a periodic change in the ammonia consumption at each monitoring point; based on this characteristic, it can be predicted based on the ammonia consumption in past cycles, so as to more accurately characterize the reference ammonia consumption by combining the predicted ammonia consumption value obtained by prediction with the previously calculated ammonia consumption.

[0083] Preferably, in some possible implementation manners of the embodiments of the present invention, the process of obtaining the reference ammonia consumption includes:

[0084] Predict the ammonia consumption of each monitoring point through the SARIMA model algorithm according to the ammonia consumption in each historical cycle time period corresponding to each monitoring point; use the sampling moment corresponding to the same cycle position of the current sampling moment in each historical cycle time period as the comparison sampling moment; determine the overall ammonia consumption of each monitoring point at the current sampling moment according to the mean value of all ammonia consumption corresponding to each monitoring point at the current sampling moment and all comparison sampling moments; determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the mean value of the predicted ammonia consumption and the overall ammonia consumption. By comprehensively characterizing the ammonia consumption situation of each monitoring point at the current moment by combining the predicted ammonia consumption that can represent the periodic similarity characteristics and the overall ammonia consumption that can represent the neighboring similarity characteristics, the obtained reference ammonia consumption can be made more accurate; it should be noted that the SARIMA model algorithm is a well-known technical means in the art and will not be further limited and described herein.

[0085] In a specific implementation manner of the embodiments of the present invention, the process of obtaining the reference ammonia consumption is expressed by the formula: ; where is the reference ammonia consumption of the th monitoring point at the current sampling moment; is the predicted ammonia consumption of the th monitoring point at the current sampling moment; is the overall ammonia consumption of the th monitoring point at the current sampling moment, that is, the average value of all ammonia consumptions corresponding to the th monitoring point at the current sampling moment and all comparison sampling moments.

[0086] By calculating the reference ammonia consumption, the preliminary prediction and correction of the ammonia consumption of each monitoring point at the current sampling moment are completed. At the same time, on the basis of the previous ones, the ammonia consumption fitting difference between each monitoring point and its neighboring points is obtained. Further, the calculated reference ammonia consumption can be further corrected according to the ammonia consumption fitting difference, so that the obtained fitting ammonia consumption is more accurate.

[0087] Preferably, in some possible implementation manners of the embodiments of the present invention, the process of obtaining the fitting ammonia consumption includes:

[0088] Taking the sum value between the reference ammonia consumption of each neighboring point corresponding to each monitoring point at the current sampling moment and the ammonia consumption fitting difference as the relative ammonia consumption of each neighboring point corresponding to each monitoring point; determining the fitting ammonia consumption of each monitoring point at the current sampling moment according to the average value of the relative ammonia consumptions of all neighboring points corresponding to each monitoring point. Since each monitoring point corresponds to multiple neighboring points, after combining the corresponding reference ammonia consumption and the ammonia consumption fitting difference, the obtained fitting ammonia consumption is more accurate by taking the average value. In a specific implementation manner of the embodiments of the present invention, the process of obtaining the fitting ammonia consumption is expressed by the formula: ; where is the fitting ammonia consumption of the th monitoring point at the current sampling moment; is the number of neighboring points of the th monitoring point; is the reference ammonia consumption of the th neighboring point corresponding to the th monitoring point at the current sampling moment; is the ammonia consumption fitting difference between the th monitoring point and the th neighboring point during the current cycle time period; is the relative ammonia consumption of the th neighboring point corresponding to the th monitoring point at the current sampling moment.

[0089] Step S105: Monitor the ammonia content of the flue gas denitration system according to the fitted ammonia consumption.

[0090] The fitted ammonia consumption characterizes the consumption of ammonia. Therefore, in order to more accurately monitor the final ammonia content, it is necessary to combine the unpurified ammonia content on this basis to characterize the final ammonia content after purification. In some possible implementation manners of the embodiments of the present invention, the process of monitoring the ammonia content of the flue gas denitration system according to the fitted ammonia consumption includes:

[0091] Determine the final ammonia content at each monitoring point by the difference between the average unpurified ammonia content and the fitted ammonia consumption. The ammonia consumption is obtained by calculating the difference between the unpurified ammonia content and the purified ammonia content. Therefore, in order to determine the final ammonia content after purification, further subtract the fitted ammonia consumption from the average unpurified ammonia content, so as to obtain a more accurate final ammonia content corrected by combining adjacent similarity and periodic similarity characteristics; among them, the formula corresponding to the process of obtaining the final ammonia content is: ; where is the final ammonia content at the th monitoring point at the current sampling time; is the average unpurified ammonia content at the th monitoring point at the current sampling time; is the fitted ammonia consumption at the th monitoring point at the current sampling time.

[0092] In summary, a method for monitoring the ammonia content of a flue gas denitration system first determines the ammonia consumption at each monitoring point based on the similarity characteristics of the ammonia content and consumption between the monitoring points in the flue of the flue gas denitration system; then determines the fitting difference of ammonia consumption based on the periodic characteristics of the ammonia content after filter bag cleaning and replacement and the similarity characteristics of the ammonia content of adjacent monitoring points; thus combines the periodic similarity characteristics and adjacent similarity characteristics to determine a more accurate fitted ammonia consumption at each monitoring point at the current sampling time, making the accuracy of monitoring the ammonia content of the flue gas denitration system according to the fitted ammonia consumption higher.

[0093] This application also provides a system for monitoring the ammonia content of a flue gas denitration system. Please refer to Figure 2 , which shows the structure diagram of a system for monitoring the ammonia content of a flue gas denitration system provided by an embodiment of the present invention. The system includes: a data acquisition and preprocessing module 201, a first determination module 202, a second determination module 203, a third determination module 204, and an ammonia content monitoring module 205.

[0094] The data acquisition and preprocessing module 201 is used to collect the unpurified ammonia content before purification and the initial ammonia content after purification at each sampling time for each monitoring point in the flue of the flue gas denitration system; obtain the adjacent points adjacent to each monitoring point among all the monitoring points;

[0095] The first determination module 202 is used to determine the ammonia consumption of each monitoring point according to the initial ammonia content of each monitoring point, the unpurified ammonia content of each adjacent point, and the relative distance at each sampling time; determine at least two periodic time periods among all sampling times according to the periodic differential change cycle fluctuation of the ammonia consumption of each monitoring point;

[0096] The second determination module 203 is used to calculate the ammonia consumption deviation value between each monitoring point and each adjacent point at each sampling time in each periodic time period; determine the ammonia consumption fitting difference between each monitoring point and each adjacent point within the current periodic time period according to the overall similarity of the ammonia consumption deviation values between the current periodic time period and other periodic time periods, and the ammonia consumption deviation values corresponding to each sampling time in the current periodic time period;

[0097] The third determination module 204 is used to determine the reference ammonia consumption of each monitoring point at the current sampling time according to the historical ammonia consumption periodic change of each monitoring point and the overall numerical size of the ammonia consumption within the current periodic time period; determine the fitting ammonia consumption of each monitoring point at the current sampling time according to the reference ammonia consumption of each monitoring point at the current sampling time and the corresponding ammonia consumption fitting differences;

[0098] The ammonia content monitoring module 205 is used to monitor the ammonia content of the flue gas denitration system according to the fitting ammonia consumption.

[0099] It should be noted that the system provided in the above embodiments is only illustrated by the division of the above functional modules. In actual applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the computer device is divided into different functional modules to complete all or part of the functions described above. In addition, the ammonia content monitoring system of a flue gas denitration system provided in the above embodiments and the embodiment of the ammonia content monitoring method of a flue gas denitration system belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0100] The embodiment of the present application also provides a computer device. Please refer to Figure 3, which shows a schematic structural diagram of a computer device provided by an embodiment of the present invention. The computer device includes a memory 301, a processor 302, and a computer program 303 stored in the memory 301 and running on the processor 302. Wherein, when the processor 302 executes the computer program 303, the computer device can execute any one of the ammonia content monitoring methods of the flue gas denitration system introduced above.

[0101] An embodiment of the present application also provides a computer program product. When the computer program product runs on a computer device, the computer device can execute any one of the ammonia content monitoring methods of the flue gas denitration system introduced above.

[0102] An embodiment of the present application also provides a computer-readable storage medium. The computer-readable storage medium stores computer program code. When the computer program code runs on a computer device, the computer device can execute any one of the ammonia content monitoring methods of the flue gas denitration system introduced above.

[0103] In the embodiments provided in the present application, it should be understood that the provided computer device, computer program product, and computer-readable storage medium are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the methods provided above, which will not be elaborated here.

[0104] It should be noted that the above-mentioned sequence of embodiments of the present invention is only for description and does not represent the superiority or inferiority of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0105] Each embodiment in this specification is described in a progressive manner. The same or similar parts between each embodiment can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

Claims

1. A method for monitoring the ammonia content in a flue gas denitrification system, characterized in that, The method includes: In the flue of the flue gas denitrification system, collect the unpurified ammonia content before purification and the initial ammonia content after purification at each monitoring point at each sampling moment; obtain the adjacent points adjacent to each monitoring point among all monitoring points; At each sampling moment, determine the ammonia consumption of each monitoring point according to the initial ammonia content of each monitoring point, the unpurified ammonia content of each adjacent point, and the relative distance; determine at least two cycle time periods among all sampling moments according to the periodic differential change cycle fluctuation of the ammonia consumption of each monitoring point; Calculate the ammonia consumption deviation value between each monitoring point and each adjacent point at each sampling moment in each cycle time period; determine the ammonia consumption fitting difference between each monitoring point and each adjacent point within the current cycle time period according to the overall similarity of the ammonia consumption deviation values between the current cycle time period and other cycle time periods, and the ammonia consumption deviation values corresponding to each sampling moment in the current cycle time period; Determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the historical periodic change of the ammonia consumption of each monitoring point and the overall value of the ammonia consumption within the current cycle time period; determine the fitted ammonia consumption of each monitoring point at the current sampling moment according to the reference ammonia consumption of each monitoring point at the current sampling moment and the corresponding ammonia consumption fitting differences; Monitor the ammonia content of the flue gas denitrification system according to the fitted ammonia consumption; The process of obtaining the ammonia consumption fitting difference includes: For each monitoring point and each adjacent point, determine the difference confidence at each sampling moment in the current cycle time period according to the deviation sum of the ammonia consumption deviation values and the deviation rate of the ammonia consumption deviation values between the sampling moments at the corresponding cycle positions in each sampling moment of the current cycle time period and each historical cycle time period; Determine the weighted ammonia consumption difference at each sampling moment in the current cycle time period according to the product of the normalized value of the difference confidence and the ammonia consumption deviation value at each sampling moment in the current cycle time period; determine the ammonia consumption fitting difference between each monitoring point and each adjacent point within the current cycle time period according to the accumulated value of the weighted ammonia consumption differences at all sampling moments in the current cycle time period; The process of obtaining the reference ammonia consumption includes: Predict the ammonia consumption of each monitoring point at the current moment by the SARIMA model algorithm according to the ammonia consumption in each historical cycle time period corresponding to each monitoring point; Use the sampling moment corresponding to the same cycle position of the current sampling moment in each historical cycle time period as the comparison sampling moment; determine the overall ammonia consumption of each monitoring point at the current sampling moment according to the mean value of all ammonia consumption corresponding to each monitoring point at the current sampling moment and all comparison sampling moments; Determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the mean value of the predicted ammonia consumption and the overall ammonia consumption; The process of obtaining the fitted ammonia consumption includes: The sum of the reference ammonia consumption of each neighboring point corresponding to each monitoring point at the current sampling moment and the fitting ammonia consumption difference is used as the relative ammonia consumption of each neighboring point corresponding to each monitoring point; according to the mean value of the relative ammonia consumption of all neighboring points corresponding to each monitoring point, the fitting ammonia consumption of each monitoring point at the current sampling moment is determined.

2. The ammonia content monitoring method of a flue gas denitrification system according to claim 1, characterized in that, The process of obtaining the ammonia consumption includes: Each monitoring point is sequentially taken as the target point; all neighboring monitoring points within the preset neighborhood range of the target point are obtained; At each sampling moment, the distances from each neighboring monitoring point to the target point are negatively correlated and normalized to determine the distance weights of each neighboring monitoring point; according to the product of the unpurified ammonia content of each neighboring monitoring point and the distance weight, the unpurified ammonia weighted value of each neighboring monitoring point is determined; according to the cumulative value of the unpurified ammonia weighted values of all neighboring monitoring points, the average unpurified ammonia content of the target point is determined; The difference between the average unpurified ammonia content and the initial ammonia content of the target point is used as the ammonia consumption of the target point.

3. The ammonia content monitoring method of a flue gas denitrification system according to claim 1, characterized in that, The process of obtaining the periodic time period includes: After arranging the ammonia consumption of each monitoring point in chronological order, an ammonia consumption time series is obtained; the ammonia consumption time series is subjected to differential calculation to obtain an ammonia consumption difference series; the moment corresponding to the maximum value point in the ammonia consumption difference series is used as the periodic interval moment; all sampling moments are divided into at least two periodic time periods at intervals of the periodic interval moment.

4. The ammonia content monitoring method of a flue gas denitration system according to claim 1, characterized in that, The process of obtaining the difference confidence level includes: For each monitoring point and each neighboring point, according to the absolute value of the difference between the ammonia consumption deviation value at each sampling moment in the current periodic time period and the ammonia consumption deviation value at the sampling moment at the same periodic position in each historical periodic time period, the ammonia consumption periodic difference value corresponding to the current periodic time period and each historical periodic time period at each sampling moment is determined; According to the overall deviation in the change rate of the ammonia consumption deviation values at each sampling moment between the current periodic time period and each historical periodic time period, the overall periodic difference between the current periodic time period and each historical periodic time period is determined; The product of the normalized value of the overall periodic difference and the ammonia consumption periodic difference value is used as the weighted periodic difference value between the current periodic time period and each historical periodic time period at each sampling moment; the cumulative value of all weighted periodic difference values corresponding to each sampling moment in the current periodic time period is negatively correlated and mapped to determine the difference confidence level at each sampling moment in the current periodic time period.

5. A method for monitoring the ammonia content of a flue gas denitrification system according to claim 4, characterized in that, The process of obtaining the overall periodic difference includes: The difference between the ammonia consumption deviation value at the next sampling moment corresponding to each sampling moment and the ammonia consumption deviation value at the previous sampling moment is used as the ammonia consumption difference change rate; after arranging the ammonia consumption change rates of all sampling moments in each periodic time period in chronological order, the ammonia consumption change rate series of each periodic time period is determined; the DTW distance between the two ammonia consumption change rate series corresponding to the current periodic time period and each historical periodic time period is used as the corresponding overall periodic difference.

6. The ammonia content monitoring method of a flue gas denitrification system according to claim 2, characterized in that, The process of monitoring the ammonia content in the flue gas denitration system according to the fitted ammonia consumption includes: Determine the final ammonia content at each monitoring point based on the difference between the average unpurified ammonia content and the fitted ammonia consumption.

7. An ammonia content monitoring system for a flue gas denitrification system, characterized in that, The system includes: A data acquisition and preprocessing module, which is used to collect the unpurified ammonia content before purification and the initial ammonia content after purification at each sampling moment at each monitoring point in the flue of the flue gas denitration system; obtain adjacent points adjacent to each monitoring point among all monitoring points; A first determination module, which is used to determine the ammonia consumption at each monitoring point according to the initial ammonia content at each monitoring point, the unpurified ammonia content at each adjacent point, and the relative distance at each sampling moment; determine at least two cycle time periods among all sampling moments according to the periodic differential change cycle fluctuation of the ammonia consumption at each monitoring point; A second determination module, which is used to calculate the ammonia consumption deviation value between each monitoring point and each adjacent point at each sampling moment in each cycle time period; determine the fitting difference of ammonia consumption between each monitoring point and each adjacent point within the current cycle time period according to the overall similarity of the ammonia consumption deviation values between the current cycle time period and other cycle time periods, and the ammonia consumption deviation values corresponding to each sampling moment in the current cycle time period; The process of obtaining the fitting difference of ammonia consumption includes: For each monitoring point and each adjacent point, determine the difference confidence at each sampling moment in the current cycle time period according to the deviation sum of the ammonia consumption deviation values and the deviation rate of the ammonia consumption deviation values between each sampling moment in the current cycle time period and the sampling moments at the corresponding cycle positions in each historical cycle time period; Determine the weighted ammonia consumption difference at each sampling moment in the current cycle time period according to the product of the normalized value of the difference confidence and the ammonia consumption deviation value at each sampling moment in the current cycle time period; determine the fitting difference of ammonia consumption between each monitoring point and each adjacent point within the current cycle time period according to the cumulative value of the weighted ammonia consumption differences at all sampling moments in the current cycle time period; A third determination module, which is used to determine the reference ammonia consumption at each monitoring point at the current sampling moment according to the historical periodic change of the ammonia consumption at each monitoring point and the overall numerical size of the ammonia consumption within the current cycle time period; determine the fitted ammonia consumption at each monitoring point at the current sampling moment according to the reference ammonia consumption at each monitoring point at the current sampling moment and the corresponding fitting differences of ammonia consumption; The process of obtaining the reference ammonia consumption includes: Predict the ammonia consumption at each monitoring point at the current moment by using the SARIMA model algorithm based on the ammonia consumption in each historical cycle time period corresponding to each monitoring point; Take the sampling moment corresponding to the same cycle position of the current sampling moment in each historical cycle time period as the comparison sampling moment; determine the overall ammonia consumption at each monitoring point at the current sampling moment according to the mean value of all ammonia consumption corresponding to each monitoring point at the current sampling moment and all comparison sampling moments; Determine the reference ammonia consumption of each monitoring point at the current sampling moment according to the predicted ammonia consumption and the mean value of the overall ammonia consumption; The process of obtaining the fitted ammonia consumption includes: Take the sum value between the reference ammonia consumption of each neighboring point corresponding to each monitoring point at the current sampling moment and the ammonia consumption fitting difference as the relative ammonia consumption of each neighboring point corresponding to each monitoring point; determine the fitted ammonia consumption of each monitoring point at the current sampling moment according to the mean value of the relative ammonia consumption of all neighboring points corresponding to each monitoring point; An ammonia content monitoring module, which is used to monitor the ammonia content of the flue gas denitration system according to the fitted ammonia consumption.

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