Multi-channel automatic calibration type flue gas sampling probe

Abstract

The utility model discloses a multi-channel automatic calibration type flue gas sampling probe which comprises a sampling probe I and a sampling probe II, the sampling probe I and the sampling probe II are of the same structure, the sampling probe I and the sampling probe II comprise a plurality of independent sampling ports, filter elements are arranged on the sampling ports, and the filter elements are arranged on the sampling ports. The sampling probe I and the sampling probe II are mounted in a near-wall area of a flue wall, the sampling ports comprise a sampling port I, a sampling port II and a sampling port III, a filter element I is mounted behind the sampling port I, a filter element II is mounted behind the sampling port II, a filter element III is mounted behind the sampling port III, and the control electromagnetic valve group is connected with the sampling port I, the sampling port II and the sampling port III. The control electromagnetic valve group controls to open a specific sampling port in the sampling port I, the sampling port II and the sampling port III, the other end of the control electromagnetic valve group is connected with an air extractor, and the other end of the air extractor is connected with a compressed air source. According to the utility model, the sampling probe I and the sampling probe II are arranged, and the multi-channel design is adopted, so that a wider flue gas area is covered.

Description

Technical Field

[0001] This utility model relates to a multi-channel automatic calibration flue gas sampling probe. Background Technology

[0002] Coal-fired power plants generate flue gas containing various pollutants during power generation, with nitrogen oxides (NOx) emissions being of particular concern due to their direct impact on air quality and their role as a major contributor to acid rain and photochemical smog. To comply with stringent environmental regulations, such as the "Emission Standard for Air Pollutants from Thermal Power Plants," coal-fired power plants must implement effective measures to control NOx emissions, ensuring that their concentrations remain below the prescribed limits, generally not exceeding 100 mg / m³. 3 In some regions, this standard has been tightened to 50 mg / m³. 3 Selective catalytic reduction (SCR) is a widely used and highly efficient denitrification method in coal-fired power plants. Its basic principle is to use ammonia (NH3) as a reducing agent, which reacts with NOx in flue gas under the action of a catalyst, converting it into harmless nitrogen (N2) and water (H2O). However, to achieve the ideal denitrification effect, the amount of ammonia injected must be precisely controlled to avoid ammonia escape. In the presence of SO3 and H2O in the flue gas, especially at lower temperatures, ammonia forms highly viscous ammonium bisulfate (NH4HSO4). The accumulation of this substance can poison the catalyst, reduce denitrification efficiency, and may also clog the air preheater, causing corrosion, which in turn increases the flue gas temperature, increases the load on the induced draft fan, and in severe cases, even forces unplanned unit shutdowns, posing a significant threat to the safe and stable operation of the denitrification system. Therefore, ensuring accurate measurement and strict control of ammonia escape during the operation of thermal power units is particularly important. This not only helps protect the environment and reduce unnecessary economic losses but also ensures the long-term reliable operation of the unit and maintains the continuous and stable production of electricity. To achieve this goal, power plants need to adopt advanced monitoring technologies and equipment to monitor ammonia slip rate in real time, and combine this with an optimized control system to finely adjust the amount of ammonia added to balance the relationship between denitrification efficiency and ammonia slip, thereby achieving an economical and environmentally friendly operating state.

[0003] However, existing technologies have the following drawbacks:

[0004] 1. Lack of Sampling Representativeness: Traditional sampling probes typically employ a single-channel design, meaning the sampling points are fixed and cannot fully cover the complex flow field distribution and NOx concentration gradient within the flue gas duct. This limitation results in samples lacking representativeness, failing to accurately reflect the actual situation of the entire flue gas system, thus affecting the assessment and control of denitrification efficiency.

[0005] 2. Inconvenient manual calibration: In existing technologies, the calibration of flue gas sampling probes relies on manual operation, which is not only time-consuming and labor-intensive, but also easily affected by human factors, leading to deviations in calibration results. Manual calibration also makes it difficult to achieve real-time correction under continuous monitoring, reducing the accuracy and timeliness of sampling data.

[0006] 3. Existing flue gas sampling probes lack an effective self-calibration mechanism. Long-term operation of the sensor may lead to the accumulation of measurement errors due to aging or contamination, affecting the accuracy and reliability of the sampling data.

[0007] In order to solve these problems, this utility model is hereby proposed. Utility Model Content

[0008] The purpose of this invention is to provide a multi-channel automatic calibration flue gas sampling probe.

[0009] The objective of this utility model can be achieved through the following technical solutions:

[0010] A multi-channel automatic calibration flue gas sampling probe consists of sampling probe one and sampling probe two, which have the same structure. Sampling probe one and sampling probe two include multiple independent sampling ports, and filter elements are provided on the sampling ports. Sampling probe one and sampling probe two are installed in the near-wall area of ​​the flue wall.

[0011] Preferably, the sampling ports include sampling port one, sampling port two, and sampling port three, with filter element one installed after sampling port one, filter element two installed after sampling port two, and filter element three installed after sampling port three.

[0012] Preferably, it also includes a control solenoid valve assembly, which is connected to sampling port one, sampling port two, and sampling port three. The control solenoid valve assembly controls the opening of a specific sampling port among sampling port one, sampling port two, and sampling port three. The other end of the control solenoid valve assembly is connected to an air extraction device, and the other end of the air extraction device is connected to a compressed air source.

[0013] Preferably, the exhaust device is connected to a sample gas pipeline at its rear end. The sample gas pipeline is connected to a flue gas analyzer and a sample gas venting system. When the exhaust device is working, a portion of the flue gas is drawn through the sample gas pipeline to the flue gas analyzer for real-time analysis, and the remaining sample gas is discharged through the sample gas venting system.

[0014] Furthermore, it also includes an intelligent control unit, within which the flue gas analyzer is housed.

[0015] Furthermore, it also includes a calibration sample gas, which is connected to the sample gas pipeline via a control solenoid valve assembly, and a compressed gas source is connected to the calibration sample gas as the power source for the calibration sample gas.

[0016] Beneficial technical effects:

[0017] 1. This utility model aims to cover a wider range of flue gas areas through a multi-channel design by setting sampling probe one and sampling probe two in the near-wall area of ​​the flue wall, ensuring that the sampling data can truly reflect the overall condition of the flue gas and improve the representativeness of the sampling.

[0018] 2. This utility model introduces a self-calibration mechanism by setting a calibration sample gas, thereby enabling real-time monitoring and automatic correction of sampling accuracy, ensuring long-term data stability and accuracy, enhancing sampling accuracy and reliability, and reducing the need for manual intervention, maintenance frequency and cost. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] Figure 1 This is a schematic diagram illustrating the structural principle of a multi-channel automatic calibration flue gas sampling probe according to this utility model. Detailed Implementation

[0021] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0022] like Figure 1 As shown, a multi-channel automatic calibration flue gas sampling probe consists of sampling probe 1 and sampling probe 2. Sampling probe 1 and sampling probe 2 have the same structure. Sampling probe 1 and sampling probe 2 include multiple independent sampling ports, and filter elements are provided on the sampling ports.

[0023] In this embodiment, the sampling ports include sampling port 6, sampling port 7, and sampling port 8. Sampling port 6 is followed by filter element 3, sampling port 7 by filter element 4, and sampling port 8 by filter element 5. Sampling probe 1 and sampling probe 2 are installed in the near-wall area of ​​the flue wall 9. Sampling ports 6, 7, and 8 are optimized according to the flow field distribution and NOx concentration distribution in the flue to ensure that samples are collected from different parts of the flue gas. The filters 3, 4, and 5 installed after the sampling ports are used to remove solid particulate matter in the flue gas and protect the safety of subsequent devices.

[0024] It also includes a control solenoid valve assembly 10, which is connected to sampling port 6, sampling port 7, and sampling port 8. The control solenoid valve assembly 10 controls the opening of a specific sampling port among sampling port 6, sampling port 7, and sampling port 8. The other end of the control solenoid valve assembly 10 is connected to an air extraction device 11, and the other end of the air extraction device 11 is connected to a compressed air source 14.

[0025] The extraction device 11 starts working under the power provided by the compressed air source 14. The rear end of the extraction device 11 is connected to the sample gas pipeline 12, which is connected to the flue gas analyzer 16 and the sample gas exhaust 13. When the extraction device 11 is working, a portion of the flue gas is drawn to the flue gas analyzer 16 through the sample gas pipeline 12 for real-time analysis, and the remaining sample gas is discharged through the sample gas exhaust 13.

[0026] It also includes an intelligent control unit 17, and the flue gas analyzer 16 is installed in the intelligent control unit 17.

[0027] It also includes a calibration sample gas 15, which is connected to the sample gas pipeline 12 via a control solenoid valve group 10. A compressed gas source 14 is connected to the calibration sample gas 15 as the power source for the calibration sample gas 15.

[0028] Each probe includes multiple independent sampling ports 6, 7, and 8. These sampling ports are optimized according to the flow field distribution and NOx concentration distribution in the flue to ensure that samples are collected from different parts of the flue gas. Each sampling port is equipped with filter element 3, filter element 4, and filter element 5 to remove solid particulate matter in the flue gas and protect the safety of subsequent devices. The intelligent control unit 17 controls the solenoid valve group 10 to open a selected sampling port. The air extraction device 11 starts to work under the power provided by the compressed air source 14. A portion of the flue gas is drawn to the flue gas analyzer 16 for real-time analysis through the sample gas management 12, and the remaining sample gas is discharged through the sample gas venting 13.

[0029] The automatic calibration process is as follows: When the intelligent control unit 17 detects that the reading deviation of the flue gas analyzer 16 exceeds the preset threshold, it automatically triggers the self-calibration program, closes the current sampling channel, controls the solenoid valve group 10 to connect the sample gas pipeline 12 to the calibration sample gas 15, and pushes the calibration sample gas into the flue gas analyzer 16 through the compressed gas source 14; the flue gas analyzer 16 measures the gas concentration in the calibration sample gas and compares it with the known concentration. The intelligent control unit 17 adjusts the calibration parameters of the flue gas analyzer 16 according to the deviation until the reading is consistent with the concentration of the calibration sample gas; after the self-calibration is completed, the system returns to the sampling mode and continues to monitor the flue gas composition.

[0030] This utility model has the following technical features:

[0031] 1. Multi-channel design and optimized layout: By adopting a multi-channel design, each channel is independently equipped with a sampling port and a filter device, covering a wider flue gas area and ensuring the comprehensiveness and representativeness of the sampling. The layout of the sampling ports is scientifically planned based on the flow field distribution and NOx concentration distribution within the flue gas duct to improve the accuracy and comprehensiveness of the sampling data.

[0032] 2. Dynamic adjustment and implementation of self-calibration mechanism: The built-in calibration gas source enables real-time monitoring and automatic calibration of the channel sampling accuracy, ensuring the long-term stability and accuracy of the data; the calibration frequency can be automatically adjusted according to the system settings or real-time monitoring results to adapt to the needs of different working conditions.

[0033] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A multi-channel automatic calibration flue gas sampling probe, characterized in that, The sampling probe consists of a first sampling probe (1) and a second sampling probe (2). The first sampling probe (1) and the second sampling probe (2) have the same structure. The first sampling probe (1) and the second sampling probe (2) include multiple independent sampling ports. The sampling ports are equipped with filter elements. The first sampling probe (1) and the second sampling probe (2) are installed in the near-wall area of ​​the flue wall (9).

2. The multi-channel automatic calibration flue gas sampling probe according to claim 1, characterized in that, The sampling ports include sampling port one (6), sampling port two (7), and sampling port three (8). Filter element one (3) is installed after sampling port one (6), filter element two (4) is installed after sampling port two (7), and filter element three (5) is installed after sampling port three (8).

3. The multi-channel automatic calibration flue gas sampling probe according to claim 2, characterized in that, It also includes a control solenoid valve assembly (10), which is connected to sampling port one (6), sampling port two (7), and sampling port three (8). The control solenoid valve assembly (10) controls the opening of one of the sampling ports, sampling port one (6), sampling port two (7), and sampling port three (8). The other end of the control solenoid valve assembly (10) is connected to an air extraction device (11), and the other end of the air extraction device (11) is connected to a compressed air source (14).

4. The multi-channel automatic calibration flue gas sampling probe according to claim 3, characterized in that, The exhaust device (11) is connected to a sample gas pipeline (12) at its rear end. The sample gas pipeline (12) is connected to a flue gas analyzer (16) and a sample gas exhaust (13). When the exhaust device (11) is working, a portion of the flue gas is drawn through the sample gas pipeline (12) to the flue gas analyzer (16) for real-time analysis, and the remaining sample gas is discharged through the sample gas exhaust (13).

5. The multi-channel automatic calibration flue gas sampling probe according to claim 2, characterized in that, It also includes an intelligent control unit (17), and the flue gas analyzer (16) is located in the intelligent control unit (17).

6. The multi-channel automatic calibration flue gas sampling probe according to claim 1, characterized in that, It also includes a calibration sample gas (15), which is connected to the sample gas pipeline (12) through a control solenoid valve group (10), and a compressed gas source (14) is connected to the calibration sample gas (15) as the power source of the calibration sample gas (15).

Images