A nitrogen oxygen monitoring system
By designing a nitrogen and oxygen monitoring system, nitric oxide is converted into nitrogen dioxide using an oxidation channel and an oxygen output device. Combined with a high-pressure hot air blower and a gravity measuring device, accurate monitoring of flue gas composition is achieved, solving the problem of nitrogen oxide leakage when the denitrification device malfunctions, improving testing efficiency and accuracy, and protecting the environment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- 山西泰瑞祥科技有限公司
- Filing Date
- 2024-03-22
- Publication Date
- 2026-05-12
AI Technical Summary
In existing technologies, when denitrification devices malfunction, nitrogen oxides in the flue gas can easily leak and pollute the environment, and there is a lack of real-time monitoring methods.
A nitrogen and oxygen monitoring system was designed, including an oxidation channel, an oxygen output device, and a test chamber. The oxygen in the oxidation channel is converted into nitrogen dioxide, and the nitrogen dioxide gas sensor is used for monitoring. Combined with a high-pressure hot air blower and a gravity measuring device to monitor ammonium bisulfate, the system can accurately measure the composition of flue gas.
It enables real-time monitoring of nitrogen oxides in flue gas, reduces testing costs, improves testing accuracy and efficiency, prevents leakage of nitrogen dioxide and ammonium bisulfate, and protects the environment.
Smart Images
Figure CN118169335B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of environmental protection technology, and in particular to a nitrogen oxide monitoring system. Background Technology
[0002] Boiler combustion produces a large amount of flue gas, and the nitrogen oxides in the flue gas, when released into the atmosphere, pollute the atmosphere and form acid rain.
[0003] In related technologies, catalytic reduction processes are used to treat flue gas. However, if the denitrification unit malfunctions, a large amount of nitrogen oxides will be released into the atmosphere, polluting the environment. Therefore, real-time monitoring of the emitted flue gas is necessary to detect any nitrogen oxide leaks.
[0004] Therefore, in order to address the above-mentioned shortcomings, there is an urgent need for a nitrogen oxide monitoring system that can monitor the nitrogen oxide content in the flue gas discharged from the flue gas channel. Summary of the Invention
[0005] This invention provides a nitrogen oxide monitoring system capable of monitoring the nitrogen oxide content in flue gas discharged from a flue gas channel. The technical solution of this invention is as follows:
[0006] A nitrogen and oxygen monitoring system includes an oxidation channel, an oxygen output device, and a test chamber;
[0007] The oxidation channel is used to oxidize the flue gas to be tested that enters it. The oxygen output end of the oxygen output device passes through the oxidation channel to output oxygen into the oxidation channel. The outlet end of the oxidation channel is connected to the inside of the test chamber. A nitrogen dioxide gas sensor is installed inside the test chamber.
[0008] Optionally, the outlet of the test chamber is connected to a tail gas treatment device, which contains an alkaline solution.
[0009] Optionally, a first gas flow meter is installed at the air inlet of the test chamber, and the first gas flow meter is used to collect the flow rate of the gas entering the test chamber.
[0010] Optionally, a valve is installed at the air inlet of the test chamber.
[0011] Optionally, multiple nitrogen dioxide gas sensors are sequentially arranged in the test chamber along the direction of flue gas movement.
[0012] Optionally, a nitrogen oxide monitoring system may also include a flue gas passage and a monitoring passage;
[0013] Both the flue gas passage and the monitoring passage have connection ports on their side walls, and the flue gas passage and the monitoring passage are connected through the connection ports.
[0014] A high-pressure hot air blower is installed in the monitoring channel. The high-pressure hot air blower is used to release a high-temperature gas flow into the monitoring channel. The temperature of the high-temperature gas flow is 200~250℃, and the flow velocity of the high-temperature gas flow is greater than the flow velocity of the flue gas in the flue gas channel. A gravity measuring device is placed in the monitoring channel. The gravity measuring device is connected to a gravity sensor. The gravity sensor is used to measure the gravity change of the gravity measuring device. The connection port of the monitoring channel is located on the side wall of the channel between the high-pressure hot air blower and the gravity measuring device. The output end of the high-pressure hot air blower faces the gravity measuring device. The gravity measuring device includes at least one condensation channel, which is used to condense molten ammonium bisulfate.
[0015] The outlet of the monitoring channel is connected to the inlet of the oxidation channel.
[0016] Optionally, a filter screen is installed at the connection port of the flue gas passage.
[0017] Optionally, a baffle plate is installed upstream of the flue gas at the connection port of the flue gas channel. The baffle plate is used to block part of the flue gas so as to slow down the flue gas flow rate at the connection port of the flue gas channel.
[0018] Optionally, a second gas flow meter is installed at the connection port of the flue gas channel or the connection port of the monitoring channel. The second gas flow meter is used to measure the flow rate of the flue gas entering the monitoring channel.
[0019] Optionally, a gas check valve is installed on the side of the second gas flow meter facing the flue gas passage.
[0020] Compared with the prior art, the present invention has at least the following beneficial effects:
[0021] By setting up an oxidation channel, an oxygen output device, and a test chamber, when the flue gas to be tested enters the oxidation channel, the nitric oxide in the flue gas mixes with the oxygen output from the oxygen output device and reacts, converting nitric oxide into nitrogen dioxide. The flue gas then enters the test chamber through the oxidation channel, where a nitrogen dioxide gas sensor can detect the concentration of nitrogen dioxide in the flue gas. By setting up an oxidation channel and an oxygen output device to ensure that all nitric oxide in the flue gas is converted into nitrogen dioxide, the nitrogen dioxide content can be directly measured by the nitrogen dioxide gas sensor. The entire process requires only one gas sensor, reducing testing costs, and only requires a single measurement, improving testing efficiency and accuracy. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0023] Figure 1 This is a schematic diagram of the structure of a nitrogen and oxygen monitoring system provided in an embodiment of the present invention;
[0024] Figure 2 This is a schematic diagram of another nitrogen and oxygen monitoring system provided in an embodiment of the present invention.
[0025] In the picture:
[0026] 11-Oxidation channels;
[0027] 12-Oxygen output device;
[0028] 13-Test Chamber;
[0029] 14-Exhaust gas treatment device;
[0030] 21-Flue gas passage;
[0031] 22 - Monitoring Channels;
[0032] 23-High-pressure hot air blower;
[0033] 24- Gravity measuring device;
[0034] 25 - Condensation channel;
[0035] 26-Filter screen;
[0036] 27-Wind deflector;
[0037] 28 - Second gas flow meter;
[0038] 29 - Gas check valve. Detailed Implementation
[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0040] like Figure 1As shown, this embodiment of the invention provides a nitrogen and oxygen monitoring system, including an oxidation channel 11, an oxygen output device 12, and a test chamber 13;
[0041] The oxidation channel 11 is used to oxidize the flue gas to be tested that enters it. The oxygen output end of the oxygen output device 12 passes through the oxidation channel 11 to output oxygen into the oxidation channel 11. The outlet end of the oxidation channel 11 is connected to the inside of the test chamber 13. A nitrogen dioxide gas sensor is installed inside the test chamber 13.
[0042] In this embodiment of the invention, after the flue gas to be tested enters the oxidation channel 11, the nitric oxide in the flue gas and the oxygen output from the oxygen output device 12 react to convert the nitric oxide into nitrogen dioxide. The flue gas then enters the test chamber 13 via the oxidation channel 11, where a nitrogen dioxide gas sensor can detect the concentration of nitrogen dioxide in the flue gas. By setting up the oxidation channel 11 and the oxygen output device 12, all the nitric oxide in the flue gas to be tested is converted into nitrogen dioxide, and the concentration of nitrogen dioxide is finally directly measured by the nitrogen dioxide gas sensor. The entire process only requires setting up one gas sensor to measure nitrogen dioxide once. Compared with the scheme of measuring nitric oxide and nitrogen dioxide separately, this not only reduces the testing cost but also improves the testing efficiency and reduces the error superposition problem faced by two measurements (nitric oxide and nitrogen dioxide measured separately), thus improving the testing accuracy.
[0043] Understandably, in order to fully oxidize the nitric oxide in the flue gas being tested, the oxidation channel 11 gradually increases in size along the direction of flue gas movement, thereby slowing down the flow rate of the flue gas, increasing its pressure, and forming a high-pressure gas to fully oxidize the nitric oxide in the flue gas. In specific implementation, the length and cross-section of the oxidation channel 11 can be increased as needed to further promote oxidation.
[0044] It should be noted that the oxygen output device 12 installed in the oxidation channel 11 can provide oxygen and also provide power for the flue gas in the oxidation channel 11.
[0045] In some embodiments of the present invention, the exhaust end of the test chamber 13 is connected to a tail gas treatment device 14, which contains an alkaline solution. In this embodiment, the flue gas output from the exhaust end of the test chamber 13 enters the tail gas treatment device 14 containing the alkaline solution, and the nitrogen dioxide in the flue gas dissolves in the alkaline solution, preventing nitrogen dioxide from being released into the atmosphere and polluting the environment.
[0046] In some embodiments of the present invention, a first gas flow meter is installed at the air inlet of the test chamber 13. The first gas flow meter is used to collect the flow rate of the gas entering the test chamber 13. Specifically, the first gas flow meter can collect the volume of the flue gas entering the test chamber 13. Combined with the concentration of nitrogen dioxide collected by the nitrogen dioxide gas sensor in the test chamber 13, the total amount of nitrogen dioxide in the flue gas to be tested can be obtained.
[0047] In some embodiments of the present invention, a valve is installed at the air inlet of the test chamber 13. If the nitrogen dioxide gas sensor in the test chamber 13 detects that the nitrogen dioxide concentration is too high, the valve can be closed to prevent flue gas with a high nitrogen dioxide concentration from being discharged into the atmosphere.
[0048] In some embodiments of the present invention, multiple nitrogen dioxide gas sensors are sequentially arranged within the test chamber 13 along the direction of flue gas movement. By setting multiple nitrogen dioxide gas sensors, the average value of multiple nitrogen dioxide gas sensors can be taken when calculating the nitrogen dioxide concentration, thereby obtaining a more accurate nitrogen dioxide concentration.
[0049] Please refer to Figure 2 In some embodiments of the present invention, a nitrogen and oxygen monitoring system further includes a flue gas channel 21 and a monitoring channel 22; the side walls of both the flue gas channel 21 and the monitoring channel 22 include connection ports, and the flue gas channel 21 and the monitoring channel 22 are connected through the connection ports; a high-pressure hot air blower 23 is installed inside the monitoring channel 22, and the high-pressure hot air blower 23 is used to release a high-temperature airflow into the monitoring channel 22. The temperature of the high-temperature airflow is 200~250°C, and the flow velocity of the high-temperature airflow is greater than the flue gas flow velocity in the flue gas channel 21. A gravity measuring device 24 is provided, and a gravity sensor is connected to the gravity measuring device 24. The gravity sensor is used to measure the gravity change of the gravity measuring device 24. The connection port of the monitoring channel 22 is located on the side wall of the channel between the high-pressure hot air blower 23 and the gravity measuring device 24. The output end of the high-pressure hot air blower 23 faces the gravity measuring device 24. The gravity measuring device 24 includes at least one condensation channel 25, which is used to condense the ammonium bisulfate melt. The air outlet of the monitoring channel 22 is connected to the air inlet of the oxygen channel 11.
[0050] By incorporating these components, the embodiments of the invention enable the monitoring of ammonium bisulfate, which in turn detects whether ammonia leakage has occurred in the denitrification unit. If ammonia leakage occurs, the leaked ammonia will react with sulfur oxides in the flue gas to form ammonium bisulfate. Therefore, monitoring the ammonium bisulfate in the flue gas can determine whether ammonia leakage has occurred in the denitrification unit.
[0051] Specifically, flue gas discharged from the factory or power plant is introduced into flue gas passage 21, and then discharged into the atmosphere through flue gas passage 21. Flue gas passage 21 and monitoring passage 22 are interconnected through their respective connection ports. Some of the flue gas in flue gas passage 21 can enter monitoring passage 22 through the connection port. Monitoring passage 22 is equivalent to a real-time sampler, capable of sampling and monitoring the flue gas in flue gas passage 21 in real time. Specifically, because a high-pressure hot air fan 23 continuously outputs high-temperature airflow in monitoring passage 22, the flow rate of the high-temperature airflow is faster than the flow rate of the flue gas in flue gas passage 21, causing some of the flue gas in flue gas passage 21 to continuously enter monitoring passage 22. The flue gas entering monitoring passage 22 is heated to 150~200℃ by the high-temperature airflow. At 150~200℃, ammonium bisulfate in the flue gas is in a molten state. When the molten ammonium bisulfate passes through the condensation channel 25 of gravity measuring device 24, it continuously adheres to the condensation channel 25. The ammonium bisulfate condensing in the condensation channel 25 increases the mass of the gravity measuring device 24, and the increase in mass of the gravity sensor is the mass of the condensed ammonium bisulfate. The amount of ammonium bisulfate in the flue gas can be calculated based on the gravity change of the gravity sensor within a preset time period, thus enabling real-time monitoring of ammonium bisulfate in the flue gas.
[0052] It should be noted that the flue gas velocity in flue gas passage 21 can be controlled by a flow control valve, and the velocity of the high-temperature airflow output by the high-pressure hot air blower 23 can be controlled according to the flue gas velocity in flue gas passage 21, so that the velocity of the high-temperature airflow in monitoring channel 22 is greater than the flue gas velocity in flue gas passage 21, creating a pressure difference between flue gas passage 21 and monitoring channel 22. The flue gas in flue gas passage 21 continuously enters monitoring channel 22 under the pressure difference to complete sampling.
[0053] It should also be noted that the two connectors can be connected directly or through a connection channel.
[0054] In some embodiments of the present invention, a filter screen 26 is installed at the connection port of the flue gas passage 21. In these embodiments, if dust enters the monitoring channel 22, it may adhere to the condensation channel 25, thereby causing errors in the calculation of ammonium bisulfate. By installing a filter screen 26 at the connection port of the flue gas passage 21, some dust can be prevented from entering the monitoring channel 22.
[0055] In some embodiments of the present invention, a baffle plate 27 is installed upstream of the flue gas at the connection port of the flue gas channel 21. The baffle plate 27 is used to block part of the flue gas, thereby slowing down the flue gas flow rate at the connection port of the flue gas channel 21. In the embodiments of the present invention, the baffle plate 27 can slow down the flue gas flow rate at the connection port behind the baffle plate 27, increase the pressure difference between the flue gas channel 21 and the monitoring channel 22, and improve the sampling rate. At the same time, the flue gas flow rate in the flue gas channel 21 is relatively low, which can reduce the wind speed of the high-pressure hot air blower 23, thereby making it more energy-efficient.
[0056] Understandably, the wind deflector 27 can be either a curved crescent shape or a flat plate.
[0057] In some embodiments of the present invention, a second gas flow meter 28 is installed at the connection port of the flue gas channel 21 or the connection port of the monitoring channel 22. The second gas flow meter 28 is used to measure the flow rate of the flue gas entering the monitoring channel 22. In the embodiments of the present invention, the second gas flow meter 28 can calculate the amount of flue gas entering the monitoring channel 22 within a preset time, and combined with the gravity change of the gravity sensor within the preset time, the content of ammonium bisulfate in the flue gas can be accurately tested.
[0058] In some embodiments of the present invention, a gas check valve 29 is installed on the side of the second gas flow meter 28 facing the flue gas passage 21. By installing the gas check valve 29 on the side of the second gas flow meter 28 facing the flue gas passage 21, unidirectional flow of flue gas can be ensured.
[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A nitrogen oxide monitoring system, characterized in that, Includes oxidation channel (11), oxygen output device (12), and test chamber (13); The oxidation channel (11) is used to oxidize the flue gas to be tested that enters it. The oxygen output end of the oxygen output device (12) passes through the oxidation channel (11) to output oxygen into the oxidation channel (11). The outlet end of the oxidation channel (11) is connected to the inside of the test chamber (13). A nitrogen dioxide gas sensor is installed inside the test chamber (13). It also includes a flue gas passage (21) and a monitoring passage (22); The sidewalls of the flue gas passage (21) and the monitoring passage (22) both include connection ports, and the flue gas passage (21) and the monitoring passage (22) are connected through the connection ports; A high-pressure hot air blower (23) is installed in the monitoring channel (22). The high-pressure hot air blower (23) is used to release high-temperature airflow into the monitoring channel (22). The temperature of the high-temperature airflow is 200~250℃. The flow rate of the high-temperature airflow is greater than the flow rate of the flue gas in the flue gas channel (21). A gravity measuring device (24) is placed in the monitoring channel (22). The gravity measuring device (24) is connected to a gravity sensor. The gravity sensor is used to measure the gravity change of the gravity measuring device (24). The connection port of the monitoring channel (22) is located on the side wall of the channel between the high-pressure hot air blower (23) and the gravity measuring device (24). The output end of the high-pressure hot air blower (23) faces the gravity measuring device (24). The gravity measuring device (24) includes at least one condensation channel (25). The condensation channel (25) is used to condense the ammonium bisulfate melt. The outlet of the monitoring channel (22) is connected to the inlet of the oxidation channel (11); A filter screen (26) is installed at the connection port of the flue gas passage (21). A baffle plate (27) is installed upstream of the flue gas at the connection port of the flue gas channel (21). The baffle plate (27) is used to block part of the flue gas so as to slow down the flue gas flow rate at the connection port of the flue gas channel (21). A second gas flow meter (28) is installed at the connection port of the flue gas passage (21) or the connection port of the monitoring channel (22). The second gas flow meter (28) is used to measure the flow rate of the flue gas entering the monitoring channel (22). The second gas flow meter (28) is equipped with a gas check valve (29) on the side facing the flue gas passage (21).
2. The nitrogen oxide monitoring system according to claim 1, characterized in that, The test chamber (13) is connected to a tail gas treatment device (14) at its outlet, and the tail gas treatment device (14) is filled with alkaline solution.
3. The nitrogen oxide monitoring system according to claim 1, characterized in that, The test chamber (13) is equipped with a first gas flow meter at the air inlet end, which is used to collect the flow rate of the gas entering the test chamber (13).
4. The nitrogen oxide monitoring system according to claim 3, characterized in that, The air inlet of the test chamber (13) is equipped with a valve.
5. A nitrogen oxide monitoring system according to claim 1, characterized in that, Multiple nitrogen dioxide gas sensors are sequentially arranged in the test chamber (13) along the direction of flue gas movement.