Gas on-line analysis system and self-adaptive pretreatment method for industrial kiln and device

Abstract

The invention discloses a gas on-line analysis system and a self-adaptive pretreatment method for industrial kilns and devices, and relates to the technical field of gas analysis, the gas on-line analysis system comprises a pollutant concentration detection module, a waste gas flow observation module and a self-adaptive analysis module, the pollutant concentration detection module is used for detecting the concentration of nitric oxide in the kiln by utilizing a detection mode of an ultraviolet light detector, and the waste gas flowing observation module is used for detecting a waste gas flowing path in the kiln by utilizing an infrared induction mode; the self-adaptive analysis module is used for specifically determining the concentration of the nitric oxide currently flowing into the reaction container in combination with two detection modes, and finely adjusting the analysis result of the concentration of the nitric oxide in the reaction container; and the pollutant concentration detection module comprises an ultraviolet light detector array, a vacuum pump, a flow calculation module and a nitrogen oxide concentration recording module.

Description

Technical Field

[0001] The present invention relates to the technical field of gas analysis, and in particular to an online gas analysis system and an adaptive preprocessing method for industrial furnaces and devices. Background Art

[0002] In the high-temperature combustion environment of industrial kilns, nitrogen (N2) in the circulating exhaust gas can react with oxygen (O2) to produce nitrogen oxides (NO and NO2), which are the main pollutants. By adding ammonia (NH3) as a reducing agent, the reduction reaction can be promoted and the generation of nitrogen oxides can be reduced.

[0003] In the prior art, the concentrations of NO and NO2 are detected respectively by passing the gas through an ultraviolet light source after the gas is in a relatively static state, and detecting the degree of absorption of ultraviolet light of a specific wavelength by the gas. Due to the uneven distribution of nitrogen oxides in industrial kilns, it is difficult to accurately grasp the amount of ammonia by traditional detection methods. If the detection is in a transport pipeline, the detection is also inaccurate because the gas flow rate is too fast. If the ammonia is excessive in the reaction, it may cause "ammonia escape" during the circulation process, thereby polluting the environment. Due to the continuous discharge of exhaust gas and the continuous introduction of circulating air in the kiln, the existing ammonia concentration adjustment method appears to be lagging behind. Therefore, it is necessary to design a gas online analysis system and adaptive pretreatment method for industrial kilns and devices that are precisely matched. Summary of the invention

[0004] The object of the present invention is to provide a gas online analysis system and an adaptive pretreatment method for industrial kilns and devices to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a gas online analysis system and an adaptive pretreatment method for an industrial kiln and device, comprising a pollutant concentration detection module, an exhaust gas flow observation module, and an adaptive analysis module, wherein the pollutant concentration detection module is used to detect the nitrogen oxide concentration in the kiln using an ultraviolet light detector, the exhaust gas flow observation module is used to detect the exhaust gas flow path in the kiln using an infrared sensing method, and the adaptive analysis module is used to combine the two detection methods to specifically determine the nitrogen oxide concentration currently flowing into the reaction container, and to fine-tune the nitrogen oxide concentration analysis result of the reaction container.

[0006] According to the above technical solution, the pollutant concentration detection module includes an ultraviolet light detector array, a vacuum pump, a flow calculation module, and a nitrogen oxide concentration recording module. The ultraviolet light detector array is electrically connected to the nitrogen oxide concentration recording module. The flow calculation module is installed in the gas channel of the vacuum pump. The ultraviolet light detector array is composed of a plurality of ultraviolet light detectors and a plurality of corresponding ultraviolet light sources, and is evenly distributed on the top inner wall of the kiln.

[0007] The ultraviolet detector array is used to detect the concentration of nitrogen oxides at different positions in the kiln, the vacuum pump is used to pump exhaust gas into the reaction container, the flow calculation module is used to calculate the flow rate pumped by the exhaust gas pump according to the gas flow rate of the vacuum pump, and the nitrogen oxide concentration recording module is used to calculate the nitrogen oxide concentration according to the detection result of the ultraviolet detector array;

[0008] The exhaust gas flow observation module includes an infrared sensing device, a digital temperature imaging module, an imaging display module, a flow path depiction module, and a concentration corresponding module. The infrared sensing device is electrically connected to the digital temperature imaging module, the digital temperature imaging module is electrically connected to the imaging display module, the imaging display module is electrically connected to the flow path depiction module, and the flow path depiction module is electrically connected to the concentration corresponding module.

[0009] The infrared sensing device is installed above the exhaust gas gathering place in the kiln, and is used to detect the concentration of nitrogen oxides by infrared sensing. The digital temperature imaging module is used to digitally image the signal detected by the infrared sensing device. The imaging display module is used to distinguish and display the digital imaging according to the different concentrations of nitrogen oxides. The flow path depiction module is used to depict the flow path of the exhaust gas from the kiln to the vacuum pump according to the changes in the infrared digital imaging. The concentration corresponding module is used to correspond the nitrogen oxide concentration at the connection between the kiln and the vacuum pump according to the current flow path of the exhaust gas;

[0010] The adaptive analysis module includes a time accumulation unit, a data reading module, an information storage module, a concentration detector, a nitrogen oxide concentration verification module, and an ammonia concentration adaptation module. The data reading module is electrically connected to the concentration corresponding module and the nitrogen oxide concentration recording module, the information storage module is electrically connected to the data reading module and the concentration detector, the time accumulation unit is electrically connected to the flow calculation module, the nitrogen oxide concentration verification module is electrically connected to the information storage module, and the ammonia concentration adaptation module is electrically connected to the nitrogen oxide concentration verification module;

[0011] The concentration detector is installed at the inlet end of the reaction container and is used to detect the concentration of nitrogen oxides flowing into the reaction container. The time accumulation unit is used to count the time of exhaust gas flowing in different stages. The data reading module is used to receive the nitrogen oxide concentration detection signal. The information storage module is used to store nitrogen oxide concentration data. The nitrogen oxide concentration verification module is used to verify whether the nitrogen oxide concentration signal calculated in advance is correct. The ammonia concentration adaptation module is used to adjust the concentration of ammonia introduced into the reaction container to adapt to the nitrogen oxide concentration in the exhaust gas.

[0012] According to the above technical solution, the adaptive preprocessing method of the system is:

[0013] S0. Install an array of ultraviolet detectors at multiple parallel positions at the exhaust gas gathering place on the top of the kiln, so that the array of ultraviolet detectors can be wrapped by the exhaust gas when in use, and install a concentration detector at the entrance of the reaction container, and install an infrared sensing device in the space above the exhaust gas in the kiln;

[0014] S1. Start the kiln and discharge the exhaust gas normally, use the ultraviolet detector array to detect the nitrogen oxide concentration at different positions in the kiln, and use the digital temperature imaging module to depict the exhaust gas flow path in the plane;

[0015] S2. Real-time tracking and display of the moving path of the digital imaging. When the digital imaging of a certain area moves to the position of the kiln exhaust port, it means that the exhaust gas corresponding to the current digital imaging position is pumped into the reaction vessel. The nitrogen oxide concentration detected by the ultraviolet detector at this position is clear, and the nitrogen oxide concentration at the inlet of the current reaction vessel is calculated in advance according to the flow rate and time of the exhaust gas.

[0016] S3, using the nitrogen oxide concentration detected by the concentration detector to check the nitrogen oxide concentration calculated in advance, and adjusting the calculation result of the nitrogen oxide concentration at the inlet of the reaction container calculated in advance according to the check result;

[0017] S4. According to the nitrogen oxide concentration at the inlet of the reaction container calculated in advance, the ammonia concentration of the reaction container is adapted accordingly, so that when the exhaust gas here reaches the inlet of the reaction container, it can match the correct ammonia concentration, and the ammonia concentration of the reaction container is verified.

[0018] According to the above technical solution, in S1, the specific detection method of nitrogen oxide concentration at different positions in the kiln is:

[0019] S1-1. Identify the wavelength absorption peaks of the ultraviolet absorption spectra of nitric oxide and nitrogen dioxide, where nitric oxide is a and nitrogen dioxide is b, and use an ultraviolet light source to emit ultraviolet light of specific wavelengths a and b;

[0020] S1-2. Use an ultraviolet light detector to detect the absorption intensity at different wavelengths. The absorption intensity of nitric oxide is c 1a The absorption intensity of nitrogen dioxide is c 1b , combined with the rated emission intensity c0 of the ultraviolet light source, the absorption spectrum characteristics of the gas are obtained, among which the absorption rate of nitric oxide is The absorption rate of nitrogen dioxide is

[0021] S1-3. Calculate the concentration of nitric oxide and nitrogen dioxide based on the absorption rate, where the concentration of nitric oxide is The concentration of nitrogen dioxide is Where α is the conversion factor between ultraviolet light absorbance and concentration.

[0022] According to the above technical solution, in S2, the specific method for calculating the nitrogen oxide concentration at the current reaction container inlet in advance is: when the exhaust gas at a certain location corresponding to the location of a certain ultraviolet light detector flows out of the kiln exhaust port, the time node t0 is recorded, and the flow rate from the kiln exhaust port to the reaction container inlet is obtained by volume measurement as V, and the flow calculation module records the gas flow rate of the vacuum pump as v, then the time when the exhaust gas corresponding to the time node t0 flows into the reaction container inlet is The carbon monoxide concentration and carbon dioxide concentration measured at this time point are marked as the nitrogen oxide concentration calculated in advance.

[0023] According to the above technical solution, in S3, the specific method for verifying the nitrogen oxide concentration calculated in advance is: record The carbon monoxide concentration G detected by the concentration detector at the time node a and carbon dioxide concentration G b , traced back to the calculated concentration of nitric oxide at the stored time node t0 and the concentration of nitrogen dioxide is The NO concentration deviation coefficient and nitrogen dioxide The concentrations of nitric oxide and nitrogen dioxide measured at subsequent time points should be divided by μ a and μ b Thus, calibration is carried out.

[0024] According to the above technical solution, in S4, the specific method for adapting the ammonia concentration is: determining the ammonia concentrations required for the reduction reaction of nitric oxide and nitrogen dioxide according to the chemical reaction equation, wherein the ammonia concentration that reacts with nitric oxide is The concentration of ammonia that reacts with nitrogen dioxide is where γ a The number of parts of ammonia required to produce one part of nitric oxide, γb The number of parts of ammonia required for one part of nitrogen dioxide, the required ammonia concentration is W = W a +W b .

[0025] According to the above technical solution, in S4, the specific method for verifying the ammonia concentration of the reaction container is as follows: in the exhaust gas discharged from the reaction container after the reduction reaction, ammonia below the concentration threshold W0 needs to be detected. If the ammonia concentration is higher than the concentration threshold, the ammonia concentration introduced into the reaction container needs to be reduced. If nitrogen oxide residues are detected in the exhaust gas after the reduction, the reaction conditions of the reaction container need to be improved.

[0026] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention detects the concentrations of nitric oxide and nitrogen dioxide in the exhaust gas of the kiln by ultraviolet spectroscopy detection, and detects the flow path of the exhaust gas by infrared detection, so as to clarify the concentrations of nitric oxide and nitrogen dioxide flowing out of the kiln, achieving the effect of accurate detection, overcoming the problem of inaccurate nitrogen content detection under fast-flowing gas, and adopting the method of advance calculation, the exhaust gas can just match the appropriate concentration of ammonia when it flows into the reaction container, and will not cause the problem of excessive or insufficient ammonia. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0028] In the attached picture:

[0029] Figure 1 It is a schematic diagram of the overall module structure of the present invention;

[0030] Figure 2 It is a module tree diagram of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1-Figure 2The present invention provides a technical solution: a gas online analysis system and an adaptive pretreatment method for an industrial kiln and device, comprising a pollutant concentration detection module, an exhaust gas flow observation module, and an adaptive analysis module, wherein the pollutant concentration detection module is used to detect the nitrogen oxide concentration in the kiln by using an ultraviolet light detector, the exhaust gas flow observation module is used to detect the exhaust gas flow path in the kiln by using an infrared sensing method, and the adaptive analysis module is used to specifically determine the nitrogen oxide concentration currently flowing into the reaction container by combining the two detection methods, and to fine-tune the nitrogen oxide concentration analysis result of the reaction container;

[0033] The pollutant concentration detection module includes an ultraviolet light detector array, a vacuum pump, a flow calculation module, and a nitrogen oxide concentration recording module. The ultraviolet light detector array is electrically connected to the nitrogen oxide concentration recording module. The flow calculation module is installed in the gas channel of the vacuum pump. The ultraviolet light detector array is composed of a plurality of ultraviolet light detectors and a plurality of corresponding ultraviolet light sources, and is evenly distributed on the top inner wall of the kiln.

[0034] The ultraviolet detector array is used to detect the concentration of nitrogen oxides at different positions in the kiln, the vacuum pump is used to pump exhaust gas into the reaction container, the flow calculation module is used to calculate the flow rate pumped by the exhaust gas pump according to the gas flow rate of the vacuum pump, and the nitrogen oxide concentration recording module is used to calculate the nitrogen oxide concentration according to the detection result of the ultraviolet detector array;

[0035] The exhaust gas flow observation module includes an infrared sensing device, a digital temperature imaging module, an imaging display module, a flow path depiction module, and a concentration corresponding module. The infrared sensing device is electrically connected to the digital temperature imaging module, the digital temperature imaging module is electrically connected to the imaging display module, the imaging display module is electrically connected to the flow path depiction module, and the flow path depiction module is electrically connected to the concentration corresponding module.

[0036] The infrared sensing device is installed above the exhaust gas gathering place in the kiln, and is used to detect the concentration of nitrogen oxides by infrared sensing. The digital temperature imaging module is used to digitally image the signal detected by the infrared sensing device. The imaging display module is used to distinguish and display the digital imaging according to the different concentrations of nitrogen oxides. The flow path depiction module is used to depict the flow path of the exhaust gas from the kiln to the vacuum pump according to the changes in the infrared digital imaging. The concentration corresponding module is used to correspond the nitrogen oxide concentration at the connection between the kiln and the vacuum pump according to the current flow path of the exhaust gas;

[0037] The adaptive analysis module includes a time accumulation unit, a data reading module, an information storage module, a concentration detector, a nitrogen oxide concentration verification module, and an ammonia concentration adaptation module. The data reading module is electrically connected to the concentration corresponding module and the nitrogen oxide concentration recording module, the information storage module is electrically connected to the data reading module and the concentration detector, the time accumulation unit is electrically connected to the flow calculation module, the nitrogen oxide concentration verification module is electrically connected to the information storage module, and the ammonia concentration adaptation module is electrically connected to the nitrogen oxide concentration verification module;

[0038] The concentration detector is installed at the inlet end of the reaction container, and is used to detect the concentration of nitrogen oxides flowing into the reaction container. The time accumulation unit is used to count the time of exhaust gas flowing in different stages. The data reading module is used to receive the nitrogen oxide concentration detection signal. The information storage module is used to store the nitrogen oxide concentration data. The nitrogen oxide concentration verification module is used to verify whether the nitrogen oxide concentration signal calculated in advance is correct. The ammonia concentration adaptation module is used to adjust the concentration of ammonia introduced into the reaction container to adapt to the nitrogen oxide concentration in the exhaust gas.

[0039] The adaptive preprocessing method of this system is:

[0040] S0. Install an array of ultraviolet detectors at multiple parallel positions at the exhaust gas gathering place on the top of the kiln, so that the array of ultraviolet detectors can be wrapped by the exhaust gas when in use, and install a concentration detector at the entrance of the reaction container, and install an infrared sensing device in the space above the exhaust gas in the kiln;

[0041] S1. Start the kiln and discharge the exhaust gas normally, use the ultraviolet detector array to detect the nitrogen oxide concentration at different positions in the kiln, and use the digital temperature imaging module to depict the exhaust gas flow path in the plane;

[0042] S2. Real-time tracking and display of the moving path of the digital imaging. When the digital imaging of a certain area moves to the position of the kiln exhaust port, it means that the exhaust gas corresponding to the current digital imaging position is pumped into the reaction vessel. The nitrogen oxide concentration detected by the ultraviolet detector at this position is clear, and the nitrogen oxide concentration at the inlet of the current reaction vessel is calculated in advance according to the flow rate and time of the exhaust gas.

[0043] S3, using the nitrogen oxide concentration detected by the concentration detector to check the nitrogen oxide concentration calculated in advance, and adjusting the calculation result of the nitrogen oxide concentration at the inlet of the reaction container calculated in advance according to the check result;

[0044] S4. Adapting the ammonia concentration of the reaction container accordingly according to the nitrogen oxide concentration at the inlet of the reaction container calculated in advance, so that when the exhaust gas at this place reaches the inlet of the reaction container, it can match the correct ammonia concentration, and verifying the ammonia concentration of the reaction container;

[0045] In S1, the specific detection method of nitrogen oxide concentration at different positions in the kiln is:

[0046] S1-1. Identify the wavelength absorption peaks of the ultraviolet absorption spectra of nitric oxide and nitrogen dioxide, where nitric oxide is a and nitrogen dioxide is b, and use an ultraviolet light source to emit ultraviolet light of specific wavelengths a and b;

[0047] S1-2. Use an ultraviolet light detector to detect the absorption intensity at different wavelengths. The absorption intensity of nitric oxide is c 1a The absorption intensity of nitrogen dioxide is c 1b , combined with the rated emission intensity c0 of the ultraviolet light source, the absorption spectrum characteristics of the gas are obtained, among which the absorption rate of nitric oxide is The absorption rate of nitrogen dioxide is

[0048] S1-3. Calculate the concentration of nitric oxide and nitrogen dioxide based on the absorption rate, where the concentration of nitric oxide is The concentration of nitrogen dioxide is Where α is the conversion factor between UV absorbance and concentration;

[0049] In S2, the specific method for calculating the nitrogen oxide concentration at the current reaction container inlet in advance is: when the exhaust gas at a certain location corresponding to the location of a certain ultraviolet light detector flows out of the kiln exhaust port, the time node t0 is recorded, and the flow rate from the kiln exhaust port to the reaction container inlet is obtained by volume measurement as V. The flow calculation module records the gas flow rate of the vacuum pump as v, and the time when the exhaust gas corresponding to the time node t0 flows into the reaction container inlet is The carbon monoxide concentration and carbon dioxide concentration measured at this time point are marked as the nitrogen oxide concentration calculated in advance;

[0050] In S3, the specific method for verifying the nitrogen oxide concentration calculated in advance is: record The carbon monoxide concentration G detected by the concentration detector at the time node a and carbon dioxide concentration G b , traced back to the calculated concentration of nitric oxide at the stored time node t0 and the concentration of nitrogen dioxide is The NO concentration deviation coefficient and nitrogen dioxide The concentrations of nitric oxide and nitrogen dioxide measured at subsequent time points should be divided by μ a and μ b Thus, verification is carried out;

[0051] In S4, the specific method for adapting the ammonia concentration is: according to the chemical reaction equation, the ammonia concentrations required for the reduction reaction of nitric oxide and nitrogen dioxide are determined, wherein the ammonia concentration that reacts with nitric oxide is The concentration of ammonia that reacts with nitrogen dioxide is where γ a The number of parts of ammonia required to produce one part of nitric oxide, γ b The number of parts of ammonia required for one part of nitrogen dioxide, the required ammonia concentration is W = W a +W b ;

[0052] In S4, the specific method for verifying the ammonia concentration of the reaction container is as follows: in the exhaust gas discharged from the reaction container after the reduction reaction, ammonia below the concentration threshold W0 needs to be detected. If the ammonia concentration is higher than the concentration threshold, the ammonia concentration introduced into the reaction container needs to be reduced. If nitrogen oxide residues are detected in the exhaust gas after the reduction, the reaction conditions of the reaction container need to be improved.

[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0054] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An online gas analysis system for industrial kilns and devices, characterized by: It includes a pollutant concentration detection module, an exhaust gas flow observation module, and an adaptive analysis module. The pollutant concentration detection module is used to detect the nitrogen oxide concentration in the kiln using an ultraviolet light detector. The exhaust gas flow observation module is used to detect the exhaust gas flow path in the kiln using infrared sensing. The adaptive analysis module is used to combine the two detection methods to specifically determine the nitrogen oxide concentration currently flowing into the reaction container, and to fine-tune the nitrogen oxide concentration analysis result of the reaction container.

2. The gas online analysis system for industrial kilns and devices according to claim 1, characterized in that: The pollutant concentration detection module includes an ultraviolet light detector array, a vacuum pump, a flow calculation module, and a nitrogen oxide concentration recording module. The ultraviolet light detector array is electrically connected to the nitrogen oxide concentration recording module. The flow calculation module is installed in the gas channel of the vacuum pump. The ultraviolet light detector array is composed of a plurality of ultraviolet light detectors and a plurality of corresponding ultraviolet light sources, and is evenly distributed on the top inner wall of the kiln. The ultraviolet detector array is used to detect the concentration of nitrogen oxides at different positions in the kiln, the vacuum pump is used to pump exhaust gas into the reaction container, the flow calculation module is used to calculate the flow rate pumped by the exhaust gas pump according to the gas flow rate of the vacuum pump, and the nitrogen oxide concentration recording module is used to calculate the nitrogen oxide concentration according to the detection result of the ultraviolet detector array; The exhaust gas flow observation module includes an infrared sensing device, a digital temperature imaging module, an imaging display module, a flow path depiction module, and a concentration corresponding module. The infrared sensing device is electrically connected to the digital temperature imaging module, the digital temperature imaging module is electrically connected to the imaging display module, the imaging display module is electrically connected to the flow path depiction module, and the flow path depiction module is electrically connected to the concentration corresponding module. The infrared sensing device is installed above the exhaust gas gathering place in the kiln, and is used to detect the concentration of nitrogen oxides by infrared sensing. The digital temperature imaging module is used to digitally image the signal detected by the infrared sensing device. The imaging display module is used to distinguish and display the digital imaging according to the different concentrations of nitrogen oxides. The flow path depiction module is used to depict the flow path of the exhaust gas from the kiln to the vacuum pump according to the changes in the infrared digital imaging. The concentration corresponding module is used to correspond the nitrogen oxide concentration at the connection between the kiln and the vacuum pump according to the current flow path of the exhaust gas; The adaptive analysis module includes a time accumulation unit, a data reading module, an information storage module, a concentration detector, a nitrogen oxide concentration verification module, and an ammonia concentration adaptation module. The data reading module is electrically connected to the concentration corresponding module and the nitrogen oxide concentration recording module, the information storage module is electrically connected to the data reading module and the concentration detector, the time accumulation unit is electrically connected to the flow calculation module, the nitrogen oxide concentration verification module is electrically connected to the information storage module, and the ammonia concentration adaptation module is electrically connected to the nitrogen oxide concentration verification module; The concentration detector is installed at the inlet end of the reaction container and is used to detect the concentration of nitrogen oxides flowing into the reaction container. The time accumulation unit is used to count the time of exhaust gas flowing in different stages. The data reading module is used to receive the nitrogen oxide concentration detection signal. The information storage module is used to store nitrogen oxide concentration data. The nitrogen oxide concentration verification module is used to verify whether the nitrogen oxide concentration signal calculated in advance is correct. The ammonia concentration adaptation module is used to adjust the concentration of ammonia introduced into the reaction container to adapt to the nitrogen oxide concentration in the exhaust gas.

3. The gas online analysis system for industrial kilns and devices according to claim 2, characterized in that: The adaptive preprocessing method of this system is: S0. Install an array of ultraviolet detectors at multiple parallel positions at the exhaust gas gathering place on the top of the kiln, so that the array of ultraviolet detectors can be wrapped by the exhaust gas when in use, and install a concentration detector at the entrance of the reaction container, and install an infrared sensing device in the space above the exhaust gas in the kiln; S1. Start the kiln and discharge the exhaust gas normally, use the ultraviolet detector array to detect the nitrogen oxide concentration at different positions in the kiln, and use the digital temperature imaging module to depict the exhaust gas flow path in the plane; S2. Real-time tracking and display of the moving path of the digital imaging. When the digital imaging of a certain area moves to the position of the kiln exhaust port, it means that the exhaust gas corresponding to the current digital imaging position is pumped into the reaction vessel. The nitrogen oxide concentration detected by the ultraviolet detector at this position is clear, and the nitrogen oxide concentration at the inlet of the current reaction vessel is calculated in advance according to the flow rate and time of the exhaust gas. S3, using the nitrogen oxide concentration detected by the concentration detector to check the nitrogen oxide concentration calculated in advance, and adjusting the calculation result of the nitrogen oxide concentration at the inlet of the reaction container calculated in advance according to the check result; S4. According to the nitrogen oxide concentration at the inlet of the reaction container calculated in advance, the ammonia concentration of the reaction container is adapted accordingly, so that when the exhaust gas here reaches the inlet of the reaction container, it can match the correct ammonia concentration, and the ammonia concentration of the reaction container is verified.

4. The gas online analysis system for industrial kilns and devices according to claim 3 is characterized by: In S1, the specific detection method of nitrogen oxide concentration at different positions in the kiln is: S1-1. Identify the wavelength absorption peaks of the ultraviolet absorption spectra of nitric oxide and nitrogen dioxide, where nitric oxide is a and nitrogen dioxide is b, and use an ultraviolet light source to emit ultraviolet light of specific wavelengths a and b; S1-2. Use an ultraviolet light detector to detect the absorption intensity at different wavelengths. The absorption intensity of nitric oxide is c 1a The absorption intensity of nitrogen dioxide is c 1b , combined with the rated emission intensity c0 of the ultraviolet light source, the absorption spectrum characteristics of the gas are obtained, among which the absorption rate of nitric oxide is The absorption rate of nitrogen dioxide is S1-3. Calculate the concentration of nitric oxide and nitrogen dioxide based on the absorption rate, where the concentration of nitric oxide is The concentration of nitrogen dioxide is Where α is the conversion factor between ultraviolet light absorbance and concentration.

5. The gas online analysis system for industrial kilns and devices according to claim 4, characterized in that: In S2, the specific method for calculating the nitrogen oxide concentration at the current reaction container inlet in advance is: when the exhaust gas at a certain location corresponding to the location of a certain ultraviolet light detector flows out of the kiln exhaust port, the time node t0 is recorded, and the flow rate from the kiln exhaust port to the reaction container inlet is obtained by volume measurement as V, and the flow calculation module records the gas flow rate of the vacuum pump as v, then the time when the exhaust gas corresponding to the time node t0 flows into the reaction container inlet is The carbon monoxide concentration and carbon dioxide concentration measured at this time point are marked as the nitrogen oxide concentration calculated in advance.

6. The gas online analysis system for industrial kilns and devices according to claim 5, characterized in that: In S3, the specific method for verifying the nitrogen oxide concentration calculated in advance is: record The carbon monoxide concentration G detected by the concentration detector at the time node a and carbon dioxide concentration G b , traced back to the calculated concentration of nitric oxide at the stored time node t0 and the concentration of nitrogen dioxide is The NO concentration deviation coefficient and nitrogen dioxide The concentrations of nitric oxide and nitrogen dioxide measured at subsequent time points should be divided by μ a and μ b Thus, verification is carried out.

7. The gas online analysis system for industrial kilns and devices according to claim 6, characterized in that: In S4, the specific method for adapting the ammonia concentration is: determining the ammonia concentrations required for the reduction reaction of nitric oxide and nitrogen dioxide according to the chemical reaction equation, wherein the ammonia concentration that reacts with nitric oxide is The concentration of ammonia that reacts with nitrogen dioxide is where γ a The number of parts of ammonia required to produce one part of nitric oxide, γ b The number of parts of ammonia required for one part of nitrogen dioxide, the required ammonia concentration is W = W a +W b .

8. The gas online analysis system for industrial kilns and devices according to claim 7, characterized in that: In S4, the specific method for verifying the ammonia concentration of the reaction container is as follows: in the exhaust gas discharged from the reaction container after the reduction reaction, ammonia below the concentration threshold W0 needs to be detected. If the ammonia concentration is higher than the concentration threshold, the ammonia concentration introduced into the reaction container needs to be reduced. If nitrogen oxide residues are detected in the exhaust gas after the reduction, the reaction conditions of the reaction container need to be improved.

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