A method for calibrating flue environment dust instrument

Abstract

The invention discloses a flue environment dust instrument calibration method, comprising the following steps: firstly, a flue dust environment simulation device is provided, comprising a heat-insulating air supply bin and a heat-insulating mixing bin, a dust generating device is arranged in the heat-insulating air supply bin, a dust diffusion cylinder and a humidifying device are arranged in the heat-insulating mixing bin, and a heat-insulating dust outlet pipe and a horizontal wind tunnel are arranged downstream of the heat-insulating mixing bin; a first sampling tube installation port and a second sampling tube installation port are arranged at the bottom of the horizontal wind tunnel, a temperature and humidity sensor and an operation window are also arranged on the side wall thereof, a first filtering device, an exhaust fan and an air path distribution chamber are connected downstream thereof, and then various interfaces are connected, the exhaust fan, the electric heater and the humidifying device are started to circulate the internal gas, when the wind speed and the temperature and humidity reach the set values, the dust generating device is started to form a uniform dust-containing airflow, and the instrument to be calibrated is calibrated, and the method meets the requirements of dust detection in a flue environment with high temperature and high humidity.

Description

Technical Field

[0001] The invention relates to a flue environment dust meter calibration method, belonging to the technical field of dust meter calibration. Background Art

[0002] The calibration of dust meters generally requires a dust environment simulation, and then the dust meter is placed in the corresponding simulated dust environment for sampling, so as to achieve calibration in the same environment as the actual sampling environment. The current dust environment simulation generally simulates a conventional dust environment, and the dust environment simulation mainly includes horizontal wind tunnel environment simulation and vertical sedimentation environment simulation. For example, the public document with the publication number CN221860213U discloses a vertical high-concentration dust environment simulation device, which belongs to the simulation of the vertical sedimentation environment; and the invention disclosure document with the publication number CN114235322A discloses a horizontal wind tunnel dust environment simulation, but these two environmental simulations cannot simulate the chimney flue environment, because the chimney flue environment has the following major characteristics: 1. The temperature is relatively high; 2. The humidity is relatively high; 3. The wind speed is relatively fast, and the above-mentioned environmental simulation device is difficult to simulate the flue dust environment. However, simulating the flue dust environment can facilitate the calibration of the flue dust concentration detection instrument. Therefore, the simulation of the flue dust environment is particularly important. It is easy for the dust instrument to be calibrated in a conventional dust environment and then detect inaccurately in a special high temperature and high humidity flue environment. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a flue environment dust meter calibration method, which performs dust meter calibration in a simulated flue environment to meet the requirements of dust detection in a high temperature and high humidity flue environment.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a flue environment dust instrument calibration method, comprising the following steps:

[0005] S1. Provide a flue dust environment simulation device, including a heat-insulating air-supplementing bin and a heat-insulating mixing bin which are interconnected, a circulation reflux port being provided on the heat-insulating air-supplementing bin, a dust-generating device being provided in the heat-insulating air-supplementing bin, the heat-insulating mixing bin including an upstream steady-flow chamber section and a downstream mixing chamber section, a honeycomb steady-flow plate being provided between the steady-flow chamber section and the heat-insulating air-supplementing bin, a plurality of steady-flow mesh plates perpendicular to the gas flow direction being provided in the steady-flow chamber section, a conical dust diffusion tube being provided in the heat-insulating mixing bin, the dust diffusion tube penetrating the steady-flow chamber section, an upstream end of the dust diffusion tube being a small-diameter end and extending into the heat-insulating air-supplementing bin and being connected with the dust-generating port of the dust-generating device, a downstream end of the dust diffusion tube being a large-diameter end and being connected with the mixing chamber section downstream of the heat-insulating mixing bin, a humidifying device being further connected in the mixing chamber section, a shrinking heat-insulating dust outlet pipe being provided downstream of the mixing chamber section, and a horizontal wind tunnel being provided downstream of the heat-insulating dust outlet pipe;

[0006] The horizontal wind tunnel includes a high-speed wind measuring section, an expanded mixing section, a first uniform flow section and a second uniform flow section which are connected in sequence according to the flow direction of the airflow. The high-speed wind measuring section is a wind measuring section with a constant cross section and is fixedly connected to the heat-insulating dust outlet pipe. The high-speed wind measuring section is connected to the small-diameter end of the expanded mixing section. The high-speed wind measuring section is provided with a window door for convenient placement and calibration of a high-speed anemometer and a high-speed standard connection port for connecting a standard high-speed anemometer. The large-diameter end of the expanded mixing section is connected to the first uniform flow section. The first uniform flow section and the second uniform flow section have the same diameter and a circular cross section. The top of the second uniform flow section is provided with a low-speed standard connection port for convenient connection to a standard low-speed anemometer. The bottom of the second uniform flow section is provided with a first sampling tube installation port and a second sampling tube installation port for convenient installation of a sampling tube of a dust meter. A temperature and humidity sensor for detecting the temperature and humidity of the internal environment is also installed on the side wall of the second uniform flow section. An operation window is also provided on the side wall of the second uniform flow section, and an openable and closable operation compartment door is installed at the operation window.

[0007] A first filter device is connected downstream of the second uniform flow section, an exhaust fan is connected downstream of the first filter device, an air outlet of the exhaust fan is connected to an air distribution chamber, a circulating air return port and an exhaust port are provided on the air distribution chamber, the circulating air return port is connected to the circulating return port through a circulating pipe, an electric heater and an air supply port are provided on the circulating pipe, and valves are provided on the exhaust port, the circulating air return port and the air supply port;

[0008] S2. Connect the standard dust meter and the dust meter to be calibrated to the first sampling tube installation port and the second sampling tube installation port respectively, install the standard high-speed anemometer on the high-speed standard connection port; connect the standard low-speed anemometer on the low-speed standard connection port; close the exhaust port valve and open the circulating return air port valve;

[0009] S3, start the exhaust fan, electric heater and humidification device to circulate the internal gas, the standard low-speed anemometer and temperature and humidity sensor respectively detect the wind speed and temperature and humidity inside the second uniform flow section, the electric heater heats the gas circulating back to the heat-insulating gas replenishment bin to increase the temperature of the entire system, and the humidification device humidifies the internal environment;

[0010] S4. When the wind speed and temperature and humidity of the second uniform flow section reach the highest wind speed and the highest temperature and humidity in the set wind speed group and the temperature and humidity group, dynamically adjust the power of the electric heater and the humidifying device so that the wind speed, temperature and humidity in the second uniform flow section fluctuate within the range of ±5% of the set highest wind speed and the highest temperature and humidity;

[0011] S5. Start the dust generating device to evenly send the dust into the conical dust diffusion cylinder to form a dust-sending airflow. The dust-sending airflow enters the mixing chamber section. The gas in the heat-insulating air supply bin passes through the honeycomb flow stabilizing plate and the flow stabilizing mesh plate in the flow stabilizing chamber section and is gradually divided into several fine airflows, which are then mixed with the dust-sending airflow and humidified in the mixing chamber section.

[0012] S6. The mixed dust-containing gas is compressed after passing through the shrinking heat-insulated dust outlet pipe, further allowing the dust in the gas to be fully mixed;

[0013] S7, after the dust-laden gas passes through the high-speed wind measuring section of the horizontal wind tunnel to measure the highest wind speed, it is dispersed into the first uniform flow section and the second uniform flow section through the flared mixing section, and finally forms a dust-laden airflow with uniform temperature in the second uniform flow section;

[0014] S8, the standard dust meter and the dust meter to be calibrated start sampling the dust-laden gas in the second uniform flow section to obtain the particle concentration under the current wind speed, current temperature and humidity environment, and compare the readings of the standard dust meter and the dust meter to be calibrated to calibrate the dust meter to be calibrated;

[0015] S9. Reduce the power of the exhaust fan, the power of the electric heater and the humidification amount of the humidifier, so that the wind speed, temperature and humidity in the second uniform flow section reach the other set wind speeds and set humidity of the wind speed group and the temperature and humidity group in turn, and complete the calibration under other set wind speed and set humidity environments according to the previous calibration method; if the difference between the set wind speed value and the set temperature and humidity value at the current calibration and the set wind speed and set temperature and humidity at the last calibration is greater than the set difference, open the valves on the exhaust port and the air supply port and adjust the opening so that part of the gas is discharged from the exhaust port, and the remaining part of the gas flows back to the insulation air supply bin, and new gas is added through the air supply port, so that the temperature and humidity in the entire horizontal wind tunnel drop rapidly and stabilize to the set wind speed value and set temperature and humidity value at the current calibration, and then calibrate.

[0016] As a preferred scheme, the dust meter calibration method also includes calibrating the dust meter to be calibrated in conjunction with the membrane sampling method; at least one membrane sampling head is also fixed in the second uniform flow section, and the membrane sampling head is connected to the membrane sampling system. During the calibration, the membrane sampling system is started to perform membrane sampling. After the sampling is completed, the membrane in the membrane sampling head is taken out and weighed, and the weight before and after the membrane sampling is compared to obtain the standard dust concentration calculated by the membrane sampling method. While the standard dust concentration is used to calibrate the dust meter to be calibrated, the standard dust meter is also numerically calibrated. Therefore, the calibration method is also convenient for the calibration of the membrane sampling method. Both the dust meter to be calibrated and the standard dust meter can be calibrated with the concentration values ​​obtained by the membrane sampling method, and the calibration results are the most accurate.

[0017] As a preferred solution, the humidifying device includes a steam humidifying device and a normal temperature water mist humidifying device. When high temperature and high humidity flue environment simulation is required, the steam humidifying device is started; and the normal temperature water mist humidifying device is selectively started to adjust the water mist temperature in the mixing chamber section;

[0018] When simulating a flue environment at normal temperature and high humidity, start the normal temperature water mist humidification device. Therefore, the calibration method can be calibrated in a high temperature and high humidity environment and a normal temperature and high humidity environment to meet different calibration requirements.

[0019] As a preferred solution, the dust diffusion cylinder is located in the center of the mixing chamber section. The fine airflow formed by the honeycomb flow stabilizing plate and the flow stabilizing mesh plate wraps around the dust diffusion cylinder and enters the mixing chamber section. Therefore, the fine airflow wraps around the dust diffusion cylinder, so that the emitted dust will not remain in the dead corner of the mixing chamber section. All the fine airflows and dust enter the insulated dust outlet pipe for compression, thereby making the dust uniform and the final dust concentration fluctuates less.

[0020] As a preferred solution, the calibration method further comprises calibrating the high-speed anemometer and the low-speed anemometer;

[0021] A high-speed anemometer to be calibrated is installed in the high-speed wind measuring section; a low-speed anemometer to be calibrated is installed in the second uniform flow section. The high-speed anemometer to be calibrated is calibrated by comparing the readings of the calibrated high-speed anemometer with those of the standard high-speed anemometer, and the low-speed anemometer to be calibrated is calibrated by comparing the readings of the low-speed anemometer to be calibrated with those of the standard low-speed anemometer. This can meet the calibration needs of more instruments and ensure the accuracy of the wind speed values ​​detected during the dust instrument calibration.

[0022] After adopting the above technical scheme, the effects of the present invention are: 1. In this method, the gas in the heat-insulating air-making warehouse passes through the honeycomb flow-stabilizing plate and the flow-stabilizing mesh plate to form a large number of fine airflows that enter the mixing chamber section, so that the replenished airflow will be evenly mixed with the dust emitted by the dust diffusion tube, so that even if the air extraction volume is large, the gas in the heat-insulating air-making warehouse can be evenly replenished, and there will be no situation of excessive local airflow. Therefore, the simulation device can be suitable for the environment of large-flow chimney flues, and the dust concentration is more uniform and the concentration fluctuation is smaller; 2. The simulation device utilizes the gas path to distribute the chamber gas circulation, and the circulating gas flows back to the heat-insulating air-making warehouse through the circulating pipe. When circulating back, it will be heated by the electric heater, which makes full use of the thermal energy and reduces heat There is no waste of gas, and when the temperature in the entire horizontal wind tunnel needs to be cooled down, the temperature can be adjusted by controlling the circulating reflux volume and the exhaust volume of the exhaust port. This can adjust the temperature more quickly and avoid the situation where the temperature changes too slowly due to direct control of the power of the electric heater. At the same time, when stability is required, it can also be stabilized by controlling the reflux volume and exhaust volume of the gas. After the temperature is stable, if a small range of temperature adjustment is required, it can also be slowly adjusted by controlling the reflux volume and exhaust volume of the gas; 3. The simulation device is provided with a humidifying device, which can humidify the gas in the mixing chamber section to simulate the high humidity environment in the flue. Therefore, the calibration method can accurately simulate the flue dust environment for calibration, so that the calibrated dust meter is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0024] Figure 1 This is a three-dimensional diagram of a flue dust environment simulation device according to an embodiment of the present invention;

[0025] Figure 2 It is a three-dimensional diagram of a flue dust environment simulation device from another angle according to an embodiment of the present invention;

[0026] Figure 3 This is a front view of a flue dust environment simulation device according to an embodiment of the present invention;

[0027] Figure 4 It is a top view of the heat-insulating air supply bin, the heat-insulating mixing bin and the heat-insulating dust outlet pipe of an embodiment of the present invention;

[0028] Figure 5 yes Figure 4 Section view along AA;

[0029] Figure 6 It is a schematic diagram of the structure of the heat-insulating air supply bin, the heat-insulating mixing bin and the heat-insulating dust outlet pipe in an embodiment of the present invention;

[0030] In the attached drawings: 1. Insulated air supply bin; 2. Insulated mixing bin; 21. Flow stabilizing chamber section; 22. Mixing chamber section; 23. Honeycomb flow stabilizing plate; 24. Flow stabilizing mesh plate; 25. Dust diffusion cylinder; 3. Electric heater; 4. Dust generating device; 5. Insulated dust outlet pipe; 6. Horizontal wind tunnel; 61. High-speed wind measurement section; 62. Expanded mixing section; 63. First uniform flow section; 64. Second uniform flow section; 65. High-speed standard connection port; 66. Low-speed standard connection port; 67. First sampling tube installation port; 68. Second sampling tube installation port; 69. Temperature and humidity sensor; 610. Operation chamber door; 611. Window door; 7. First filter device; 8. Exhaust fan; 9. Air distribution chamber; 10. Steam humidification device; 11. Normal temperature water mist humidification device; 12. Air supply port; 13. Circulation pipeline; 14. Second filter device. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below through specific examples.

[0032] like Figure 1-6 As shown, a flue environment dust instrument calibration method comprises the following steps:

[0033] S1. Provide a flue dust environment simulation device, including a heat preservation gas replenishment bin 1 and a heat preservation mixing bin 2 which are interconnected, the heat preservation gas replenishment bin 1 is provided with a circulation reflux port, the heat preservation gas replenishment bin 1 is provided with a dust generating device 4, the heat preservation mixing bin 2 includes an upstream stabilizing chamber section 21 and a downstream mixing chamber section 22, a honeycomb stabilizing plate 23 is provided between the stabilizing chamber section 21 and the heat preservation gas replenishment bin 1, a plurality of stabilizing mesh plates 24 which are perpendicular to the gas flow direction are provided in the stabilizing chamber section 21, and the heat preservation mixing bin 2 includes a plurality of stabilizing mesh plates 24 which are perpendicular to the gas flow direction and ... 2 is provided with a conical dust diffusion cylinder 25, the dust diffusion cylinder 25 penetrates the steady flow chamber section 21, the upstream end of the dust diffusion cylinder 25 is a small diameter end and extends into the heat preservation air replenishment bin 1 and communicates with the dust generating port of the dust generating device 4, the downstream end of the dust diffusion cylinder 25 is a large diameter end and communicates with the mixing chamber section 22 downstream of the heat preservation mixing bin 2, the mixing chamber section 22 is also connected with a humidifying device, the downstream of the mixing chamber section 22 is provided with a shrinking heat preservation dust outlet pipe 5, and the downstream of the heat preservation dust outlet pipe 5 is provided with a horizontal wind tunnel 6;

[0034] The horizontal wind tunnel 6 includes a high-speed wind measuring section 61, an expanded mixing section 62, a first uniform flow section 63 and a second uniform flow section 64 which are connected in sequence according to the flow direction of the airflow. The high-speed wind measuring section 61 is a wind measuring section with a constant cross section and is fixedly connected to the heat-insulating dust outlet pipe 5. The high-speed wind measuring section 61 is connected to the small-diameter end of the expanded mixing section 62. The high-speed wind measuring section 61 is provided with a window door 611 for conveniently placing and calibrating a high-speed anemometer and a high-speed standard connection port 65 for connecting a standard high-speed anemometer. The large-diameter end of the expanded mixing section 62 is connected to the first uniform flow section 63. The first uniform flow section 64 is connected to the first uniform flow section 63. The diameters of the section 63 and the second uniform flow section 64 are the same and the cross-section is circular. The top of the second uniform flow section 64 is provided with a low-speed standard connection port 66 for conveniently connecting a standard low-speed anemometer. The bottom of the second uniform flow section 64 is provided with a first sampling tube installation port 67 and a second sampling tube installation port 68 for conveniently installing a sampling tube of a dust meter. A temperature and humidity sensor 69 for detecting the temperature and humidity of the internal environment is also installed on the side wall of the second uniform flow section 64; an operation window is also provided on the side wall of the second uniform flow section 64, and an openable and closable operation compartment door 610 is installed at the operation window;

[0035] The second uniform flow section 64 is connected to the downstream of the first filter device 7, and the first filter device 7 is connected to the downstream of the exhaust fan 8, and the air outlet of the exhaust fan 8 is connected to the air path distribution chamber 9, and the air path distribution chamber 9 is provided with a circulating return air port and an exhaust air port, and the circulating return air port is connected to the circulating return port through a circulating pipe 13, and the circulating pipe 13 is provided with an electric heater 3 and an air supply port 12, and the exhaust air port, the circulating return air port and the air supply port 12 are all provided with valves;

[0036] The humidifying device includes a steam humidifying device 10 and a normal temperature water mist humidifying device 11. When a high temperature and high humidity flue environment simulation is required, the steam humidifying device 10 is started; and the normal temperature water mist humidifying device 11 is selectively started to adjust the water mist temperature in the mixing chamber section 22; when a normal temperature and high humidity flue environment simulation is performed, the normal temperature water mist humidifying device 11 is started,

[0037] The dust diffusion tube 25 is located at the center of the mixing chamber section 22 . The fine airflow formed by the honeycomb flow stabilizing plate 23 and the flow stabilizing mesh plate 24 wraps around the dust diffusion tube 25 and enters the mixing chamber section 22 .

[0038] S2, respectively connect the standard dust meter and the dust meter to be calibrated to the first sampling tube installation port 67 and the second sampling tube installation port 68, install the standard high-speed anemometer to the high-speed standard connection port 65; connect the standard low-speed anemometer to the low-speed standard connection port 66, close the exhaust port valve and open the circulating return port valve;

[0039] S3, start the exhaust fan 8, the electric heater 3 and the humidifying device to circulate the internal gas, the standard low-speed anemometer and the temperature and humidity sensor 69 respectively detect the wind speed and temperature and humidity inside the second uniform flow section 64, the electric heater 3 heats the gas circulating back to the heat preservation gas replenishment bin 1 to increase the temperature of the entire system, and the humidifying device humidifies the internal environment of the heat preservation mixing bin 2;

[0040] S4, when the wind speed and temperature and humidity of the second uniform flow section 64 reach the highest wind speed and the highest temperature and humidity in the set wind speed group and the temperature and humidity group, dynamically adjust the power of the electric heater 3 and the humidifying device so that the wind speed, temperature and humidity in the second uniform flow section 64 fluctuate within the range of ±5% of the set highest wind speed and the highest temperature and humidity;

[0041] S5, start the dust generating device 4 to evenly send the dust into the conical dust diffusion cylinder 25 to form a dust-sending airflow, and the dust-sending airflow enters the mixing chamber section 22. The gas in the heat-insulating air replenishing warehouse 1 passes through the honeycomb flow stabilizing plate 23 and the flow stabilizing mesh plate 24 in the flow stabilizing chamber section 21 and is gradually divided into several finer airflows, which are then mixed with the dust-sending airflow and humidified by the humidifying device in the mixing chamber section 22;

[0042] S6. The dust-containing gas in S5 is compressed after passing through the shrinking heat-insulated dust outlet pipe 5, so that the dust in the gas is further fully mixed;

[0043] S7, after the dust-laden gas passes through the high-speed wind measuring section 61 of the horizontal wind tunnel 6 to measure the highest wind speed, it is dispersed into the first uniform flow section 63 and the second uniform flow section 64 through the flared mixing section 62, and finally forms a uniform dust-laden airflow in the second uniform flow section 64;

[0044] S8, start the standard dust meter and the dust meter to be calibrated to sample the dust-containing gas in the second uniform flow section 64, obtain the particle concentration under the current wind speed, current temperature and humidity environment, and compare the readings of the standard dust meter and the dust meter to be calibrated to calibrate the dust meter to be calibrated;

[0045] S9. Reduce the power of the exhaust fan 8, the power of the electric heater 3 and the humidification amount of the humidifying device, so that the wind speed, temperature and humidity in the second uniform flow section 64 reach the other set wind speeds and set humidity of the wind speed group and the temperature and humidity group in turn, and complete the calibration under other set wind speed and set humidity environments according to the previous calibration method; if the difference between the set wind speed value and the set temperature and humidity value at the current calibration and the set wind speed and set temperature and humidity at the last calibration exceeds the set difference, open the valves on the exhaust port and the air supply port 12 and adjust the opening, so that part of the gas is discharged from the exhaust port, and the remaining part of the gas flows back to the heat-insulating air supply bin 1, and new gas is added through the air supply port 12, so that the temperature and humidity in the entire horizontal wind tunnel 6 drop rapidly and stabilize to the set wind speed value and set temperature and humidity value at the current calibration, and then calibrate.

[0046] In this embodiment, the dust meter calibration method also includes calibrating the dust meter to be calibrated in conjunction with the membrane sampling method; at least one membrane sampling head can also be fixed in the second uniform flow section 64, and the membrane sampling head is connected to the membrane sampling system. During the calibration, the membrane sampling system is started to perform membrane sampling. After the sampling is completed, the membrane in the membrane sampling head is taken out and weighed. The weight before and after the membrane sampling is compared to obtain the standard dust concentration calculated by the membrane sampling method. While the standard dust concentration is used to calibrate the dust meter to be calibrated, the standard dust meter can also be numerically calibrated.

[0047] In this embodiment, the wind speed calibration of the high-speed anemometer and the low-speed anemometer is also included:

[0048] A high-speed anemometer to be calibrated is installed in the high-speed wind measuring section 61; a low-speed anemometer to be calibrated is installed in the second uniform flow section 64, and the high-speed anemometer to be calibrated is calibrated by comparing the readings of the high-speed anemometer to be calibrated with those of a standard high-speed anemometer, and the low-speed anemometer to be calibrated is calibrated by comparing the readings of the low-speed anemometer to be calibrated with those of a standard low-speed anemometer.

[0049] In this embodiment, the first filter device 7 can be an electrostatic precipitator, and a second filter device 14 can be provided at the exhaust port according to its own needs. The steam humidification device 10 includes a steam box fixed to the outside of the mixing chamber section 22, and a heating water pump, an electric heating device and an air storage tank are provided in the steam box. The inlet of the heating water pump is connected to the water supply system, and the outlet of the heating water pump is connected to the inlet of the electric heating device. The outlet of the electric heating device is connected to the inlet of the air storage tank. The air outlet of the air storage tank is connected to a steam inlet pipe, and the outlet of the steam inlet pipe extends into the mixing chamber section 22; the normal temperature water mist humidification device 11 includes a mist inlet flange provided on the side wall of the heat-insulating mixing bin 2, and a plurality of atomizing pipe joints are provided on the mist inlet flange, and a dust diffusion cylinder A plurality of atomizing nozzles are fixed to the downstream end of 25, the atomizing pipe joint and the atomizing nozzle are connected by a pipeline, and the mist inlet flange is connected to the normal temperature water supply system. The humidifying device can be selected according to the actual simulation situation. When the steam humidifying device 10 is used for heating, high-temperature steam can be added to the mixing chamber section 22, so that a chimney flue environment with a higher temperature can be simulated. When a normal temperature water mist heating device is used, the atomization of multiple atomizing nozzles can meet the normal temperature and high humidity flue environment, and the humidification requirements of different humidity can be achieved by opening and closing different numbers of atomizing nozzles.

[0050] A plurality of side sampling calibration installation ports are also provided on the side wall of the second uniform flow section 64 , and each side sampling calibration installation port can be detachably installed with a plugging head to meet various sampling requirements.

[0051] In a flue environment dust instrument calibration method of the present invention, the gas in the heat-insulating air replenishment bin 1 passes through the honeycomb flow stabilizing plate 23 and the flow stabilizing mesh plate 24 to form a large number of fine airflows that enter the mixing chamber section 22. The replenished airflow will be evenly mixed with the dust emitted by the dust diffusion tube 25. In this way, even if the air extraction volume is large, the gas in the heat-insulating air replenishment bin 1 can be evenly replenished, and there will be no local excessive airflow. It is more suitable for the environment of a large-flow chimney flue. When working, the method also uses the gas path distribution chamber 9 to realize gas circulation. The circulating gas flows back to the heat-insulating air replenishment bin 1 through the circulation pipe 13. When flowing back, it will be heated by the electric heater 3, and the gas temperature in the horizontal wind tunnel 6 will increase.

[0052] When the temperature in the entire horizontal wind tunnel 6 needs to be cooled during use, the temperature can be adjusted by controlling the circulating reflux volume and the exhaust volume of the exhaust port, so that the temperature can be adjusted more quickly. When stability is required, it can also be stabilized by controlling the reflux volume and exhaust volume of the gas. After the temperature is stabilized, if a small range of temperature adjustment is required, it can also be slowly adjusted by controlling the reflux volume and exhaust volume of the gas to meet different temperature requirements.

[0053] The above embodiments are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Various modifications and alterations made to the technical solutions of the present invention without departing from the design spirit of the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A flue environment dust instrument calibration method, characterized in that: The following steps are involved: S1. Provide a flue dust environment simulation device, including a heat-insulating air-supplementing bin and a heat-insulating mixing bin which are interconnected, a circulation reflux port being provided on the heat-insulating air-supplementing bin, a dust-generating device being provided in the heat-insulating air-supplementing bin, the heat-insulating mixing bin including an upstream steady-flow chamber section and a downstream mixing chamber section, a honeycomb steady-flow plate being provided between the steady-flow chamber section and the heat-insulating air-supplementing bin, a plurality of steady-flow mesh plates perpendicular to the gas flow direction being provided in the steady-flow chamber section, a conical dust diffusion tube being provided in the heat-insulating mixing bin, the dust diffusion tube penetrating the steady-flow chamber section, an upstream end of the dust diffusion tube being a small-diameter end and extending into the heat-insulating air-supplementing bin and being connected with the dust-generating port of the dust-generating device, a downstream end of the dust diffusion tube being a large-diameter end and being connected with the mixing chamber section downstream of the heat-insulating mixing bin, a humidifying device being further connected in the mixing chamber section, a shrinking heat-insulating dust outlet pipe being provided downstream of the mixing chamber section, and a horizontal wind tunnel being provided downstream of the heat-insulating dust outlet pipe; The horizontal wind tunnel includes a high-speed wind measuring section, an expanded mixing section, a first uniform flow section and a second uniform flow section which are connected in sequence according to the flow direction of the airflow. The high-speed wind measuring section is a wind measuring section with a constant cross section and is fixedly connected to the heat-insulating dust outlet pipe. The high-speed wind measuring section is connected to the small-diameter end of the expanded mixing section. The high-speed wind measuring section is provided with a window door for convenient placement and calibration of a high-speed anemometer and a high-speed standard connection port for connecting a standard high-speed anemometer. The large-diameter end of the expanded mixing section is connected to the first uniform flow section. The first uniform flow section and the second uniform flow section have the same diameter and a circular cross section. The top of the second uniform flow section is provided with a low-speed standard connection port for convenient connection to a standard low-speed anemometer. The bottom of the second uniform flow section is provided with a first sampling tube installation port and a second sampling tube installation port for convenient installation of a sampling tube of a dust meter. A temperature and humidity sensor for detecting the temperature and humidity of the internal environment is also installed on the side wall of the second uniform flow section. An operation window is also provided on the side wall of the second uniform flow section, and an openable and closable operation compartment door is installed at the operation window. A first filter device is connected downstream of the second uniform flow section, an exhaust fan is connected downstream of the first filter device, an air outlet of the exhaust fan is connected to an air distribution chamber, a circulating air return port and an exhaust port are provided on the air distribution chamber, the circulating air return port is connected to the circulating return port through a circulating pipe, an electric heater and an air supply port are provided on the circulating pipe, and valves are provided on the exhaust port, the circulating air return port and the air supply port; S2. Connect the standard dust meter and the dust meter to be calibrated to the first sampling tube installation port and the second sampling tube installation port respectively, install the standard high-speed anemometer on the high-speed standard connection port; connect the standard low-speed anemometer on the low-speed standard connection port; close the exhaust port valve and open the circulating return air port valve; S3, start the exhaust fan, electric heater and humidification device to circulate the internal gas, the standard low-speed anemometer and temperature and humidity sensor respectively detect the wind speed and temperature and humidity inside the second uniform flow section, the electric heater heats the gas circulating back to the heat-insulating gas replenishment bin to increase the temperature of the entire system, and the humidification device humidifies the internal environment; S4. When the wind speed and temperature and humidity of the second uniform flow section reach the highest wind speed and the highest temperature and humidity in the set wind speed group and the temperature and humidity group, dynamically adjust the power of the electric heater and the humidifying device so that the wind speed, temperature and humidity in the second uniform flow section fluctuate within the range of ±5% of the set highest wind speed and the highest temperature and humidity; S5. Start the dust generating device to evenly send the dust into the conical dust diffusion cylinder to form a dust-sending airflow. The dust-sending airflow enters the mixing chamber section. The gas in the heat-insulating air supply bin passes through the honeycomb flow stabilizing plate and the flow stabilizing mesh plate in the flow stabilizing chamber section and is gradually divided into several fine airflows, which are then mixed with the dust-sending airflow and humidified in the mixing chamber section. S6. The mixed dust-containing gas is compressed after passing through the shrinking heat-insulated dust outlet pipe, further allowing the dust in the gas to be fully mixed; S7, after the dust-laden gas passes through the high-speed wind measuring section of the horizontal wind tunnel to measure the highest wind speed, it is dispersed into the first uniform flow section and the second uniform flow section through the flared mixing section, and finally forms a dust-laden airflow with uniform temperature in the second uniform flow section; S8, the standard dust meter and the dust meter to be calibrated start sampling the dust-laden gas in the second uniform flow section to obtain the particle concentration under the current wind speed, current temperature and humidity environment, and compare the readings of the standard dust meter and the dust meter to be calibrated to calibrate the dust meter to be calibrated; S9. Reduce the power of the exhaust fan, the power of the electric heater and the humidification amount of the humidifier, so that the wind speed, temperature and humidity in the second uniform flow section reach the other set wind speeds and set humidity of the wind speed group and the temperature and humidity group in turn, and complete the calibration under other set wind speed and set humidity environments according to the previous calibration method; if the difference between the set wind speed value and the set temperature and humidity value at the current calibration and the set wind speed and set temperature and humidity at the last calibration is greater than the set difference, open the valves on the exhaust port and the air supply port and adjust the opening so that part of the gas is discharged from the exhaust port, and the remaining part of the gas flows back to the insulation air supply bin, and new gas is added through the air supply port, so that the temperature and humidity in the entire horizontal wind tunnel drop rapidly and stabilize to the set wind speed value and set temperature and humidity value at the current calibration, and then calibrate.

2. A flue environment dust instrument calibration method as claimed in claim 1, characterized in that: The dust meter calibration method also includes calibrating the dust meter to be calibrated in conjunction with the membrane sampling method: at least one membrane sampling head is fixed in the second uniform flow section, and the membrane sampling head is connected to the membrane sampling system. During calibration, the membrane sampling system is started to perform membrane sampling. After the sampling is completed, the membrane in the membrane sampling head is taken out and weighed. The weight before and after the membrane sampling is compared to obtain the standard dust concentration calculated by the membrane sampling method. While the standard dust concentration is used to calibrate the dust meter to be calibrated, the standard dust meter is also numerically calibrated.

3. A flue environment dust instrument calibration method as claimed in claim 1, characterized in that: The humidification device includes a steam humidification device and a normal temperature water mist humidification device. When a high temperature and high humidity flue environment simulation is required, the steam humidification device is started; and the normal temperature water mist humidification device is selectively started to adjust the water mist temperature in the mixing chamber section; When simulating a normal temperature and high humidity flue environment, start the normal temperature water mist humidification device.

4. A flue environment dust instrument calibration method as claimed in claim 1, characterized in that: The dust diffusion tube is located in the center of the mixing chamber section. The fine airflow formed by the honeycomb flow stabilizing plate and the flow stabilizing mesh plate wraps the dust diffusion tube from all sides and enters the mixing chamber section.

5. A flue environment dust instrument calibration method as claimed in claim 1, characterized in that: The calibration method also includes wind speed calibration for high-speed anemometers and low-speed anemometers: A high-speed anemometer to be calibrated is installed in the high-speed wind measuring section; a low-speed anemometer to be calibrated is installed in the second uniform flow section, and the high-speed anemometer to be calibrated is calibrated by comparing the readings of the high-speed anemometer to be calibrated with those of a standard high-speed anemometer, and the low-speed anemometer to be calibrated is calibrated by comparing the readings of the low-speed anemometer to be calibrated with those of a standard low-speed anemometer.

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