Device and method for measuring dust content in gas

Abstract

The invention discloses a gas dust content measuring device which comprises a gas pipeline, a gas dust extracting device is arranged on one side of the gas pipeline, and the gas dust extracting device comprises a sampling unit, a filtering unit, a metering unit and a plurality of silica gel hoses. The sampling unit comprises a stainless steel sampling pipe with one end welded on the gas pipeline and a regulating valve arranged on the sampling pipe; the filtering unit comprises a dustproof shell and a three-stage filtering assembly which is stacked in the dustproof shell; the metering unit comprises a wet type gas flowmeter, and an inlet and an outlet of the dustproof shell are respectively connected with the adjusting valve and the wet type gas flowmeter in series through the silica gel hoses. The problems that a filter membrane of a traditional dust detection device is prone to damage, sampling data deviates and the like are effectively solved, the influence of environmental factors on measurement results is reduced, and the device is simple in structure, high in anti-interference performance, convenient to operate and capable of being widely applied to the field of gas dust content measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline dust detection, and in particular to a device and method for measuring dust content in gas. Background Art

[0002] Currently, many industrial environments have certain requirements for the dust content of the gas in the gas transmission pipeline. When the dust content is too high, it will have a certain impact on subsequent production or equipment. For example, during the operation of our company's compressor, there are requirements for the dust content in the air intake pipeline. The dust content in the air is generally required to be less than 5 mg / L. Excessive dust content can block the pneumatic valve. Therefore, it is necessary to test the air flowing in the transmission pipeline or process air pipe after dust removal and entering the compressor pneumatic valve. However, these pipelines themselves do not have strict indicators for dust content. Due to the high cost of professional dust content measurement devices and the difficulty of moving them after installation, the dust content detection in ordinary pipelines is not equipped with a separate professional dust content measurement device. Ordinary dust detection devices often use a single filter membrane structure, which has weak resistance to airflow impact. The impact of airflow can easily cause the filter membrane to break or particles to rebound, affecting measurement accuracy. In addition, traditional devices do not have strict requirements on the location of sampling points, and the sampling tubes are prone to residual moisture or gas, resulting in data deviation; therefore, a set of detection devices and methods with strong versatility, flexible disassembly and assembly, and high detection accuracy are needed. Summary of the Invention

[0003] In order to solve certain technical problems existing in the prior art, one of the purposes of this application is to provide a gas dust content measuring device with a simple structure, strong anti-interference ability and easy operation, which effectively solves the problems of easy damage of filter membrane and sampling data deviation of traditional dust detection devices, reduces the influence of environmental factors on measurement results, has a simple structure, strong anti-interference ability, and is easy to operate, and can be widely used in the field of gas dust content measurement.

[0004] The second purpose of this application is to provide a method for measuring the dust content in gas. The entire measurement method is simple to operate, highly versatile, and has a flexible collection method. It also solves the problem that traditional devices have lax requirements on the location of sampling points and the sampling tube is prone to residual moisture or gas, which leads to data deviation.

[0005] In order to solve the above existing technical problems, one of the objectives of this application is achieved by adopting the following technical solutions: A gas dust content measuring device includes a gas pipeline, a gas dust extraction device is provided on one side of the gas pipeline, the gas dust extraction device includes a sampling unit, a filtering unit, a metering unit and several silicone hoses, the sampling unit includes a stainless steel sampling tube welded to the gas pipeline at one end and a regulating valve provided on the sampling tube; the filtering unit includes a dustproof shell and a three-stage filter assembly stacked in the dustproof shell; the metering unit includes a wet gas flow meter, and the inlet and outlet of the dustproof shell are respectively connected in series with the regulating valve and the wet gas flow meter through the silicone hose.

[0006] Preferably, the three-stage filter assembly includes a stacked metal filter screen and a filter membrane, and a rubber gasket arranged on the outside of the metal filter screen and the filter membrane, and the metal filter screen is located on one side of the air inlet of the dustproof shell.

[0007] Preferably, the pore size of the filter membrane is 0.45 μm, and the metal filter is made of 304 stainless steel with a mesh size of ≥200 meshes.

[0008] Preferably, the rubber gasket is an oil-resistant rubber gasket.

[0009] Preferably, the installation position of the sampling tube is ≥1.5 times the pipe diameter away from the elbow or diameter change of the gas pipeline.

[0010] Preferably, the length of the silicone hose is no more than 15 cm, and the inner wall is polished.

[0011] Preferably, the wet gas flow meter has a measuring range of 0.5 m³ / h and a built-in temperature compensation module.

[0012] Preferably, the wet gas flow meter adjusts the gas flow rate to 3.5-4 L / min through the regulating valve.

[0013] Preferably, the dustproof shell includes a conical upper shell and a lower shell, the upper shell and the lower shell are connected by threads, a conical guide hole is provided in the upper shell, and the connecting end of the lower shell is provided with an inwardly recessed receiving groove, and an exhaust hole is provided at the bottom of the receiving groove, and the three-stage filter assembly is installed in the receiving groove and pressed by the upper shell.

[0014] The second purpose of this application is achieved by the following technical solution: A method for measuring dust content in gas, wherein the equipment involved in the method includes a gas dust content measuring device, tweezers, a dryer, and a dry weighing instrument, and the method includes: S1. After drilling a hole in the straight section of the gas pipeline, install a stainless steel sampling tube with a regulating valve; S2. Connect the filter unit to the sampling port of the stainless steel sampling tube through a silicone hose; S3. Connect the wet gas flow meter to the outlet end of the filter unit through a silicone hose; S4. Slowly open the regulating valve until the wet gas flow meter reaches 3.5-4 L / min, allowing the gas in the gas pipeline to be filtered through the filter unit and then discharged from the wet gas flow meter outlet. Dust in the gas is filtered and collected by the three-stage filter assembly in the filter unit; the gas flow rate per unit volume is calculated using the wet gas flow meter; S5. When the exhaust gas of the wet gas flow meter reaches the set target, quickly close the regulating valve and remove the filter unit; S6. Open the dust cover of the filter unit and place the entire unit in a dryer at 105°C for 2 hours. After cooling, weigh the unit until the mass is stable, ensuring that the difference between the two weighings is ≤0.3 mg. Record m1. S7. Place the dryer on a dry weighing instrument to measure and calculate the dust content. Calculate the dust content in the gas in the gas pipeline based on the dust weight and the gas flow recorded by the wet gas flow meter.

[0015] The equipment involved in the entire determination method is simple, with low procurement cost, strong versatility, easy operation, and flexible collection methods. The dryer is used to dry the filter membrane assembly at a constant temperature of 105°C to achieve a stable quality state (the difference between two weighings is ≤0.3mg). The filter unit can be directly transferred to the dryer for constant weight drying to avoid secondary contamination, solving the measurement error problems caused by the fragility of the filter membrane and irregular sampling position in traditional devices. The device has a compact structure and easy operation, and is suitable for rapid detection of instrument gas. The detection accuracy can reach 0.1mg and the repeatability error is less than 5%. It also solves the problem of traditional devices having lax requirements on the sampling point location and the easy residual moisture or gas in the sampling tube, which leads to data deviation.

[0016] Preferably, the flow rate is adjusted to 3.8 L / min by the regulating valve, and the valve is closed after sampling until the filter membrane weight gain is ≥2 mg, and the flow meter reading V (L) is recorded.

[0017] Ensure that the filter membrane weight gain is ≥2mg, which makes it more convenient and more accurate to calculate the dust content in the gas in the channel.

[0018] Preferably, the dust concentration calculation formula is: , Among them, m 2 is the weight of the membrane assembly after the experiment, m 1 is the weight of the membrane assembly before the experiment, in g; v 2 is the reading of the wet gas flow meter after the test, v 1 It is the reading of the wet gas flow meter before the test, in L.

[0019] This method can effectively calculate the dust content in the gas flowing in the gas pipeline, so that the operator can easily determine whether the air needs to be filtered for dust in the future.

[0020] Preferably, the drying weighing instrument adopts an integrated drying weighing instrument, and the dryer is integrated with the drying weighing instrument.

[0021] The integrated setting of the dryer and the drying weighing instrument can avoid the problem of dust falling and causing calculation failure when the filter unit is taken out of the dryer and placed on the drying weighing instrument, and can also avoid the problem of inaccurate final test results caused by dust being carried away by airflow.

[0022] Preferably, the dryer is equipped with color-changing silica gel for constant weight drying of the filter membrane assembly.

[0023] The color-changing silica gel can effectively absorb the moisture in the dryer, ensuring the accuracy of the filter membrane assembly during the constant weight drying process.

[0024] Preferably, the tweezers are anti-static tweezers to prevent the filter membrane from absorbing impurities during weighing.

[0025] Anti-static tweezers can effectively avoid the problem of impurities being absorbed by them and affecting the accuracy of detection data when they are used to contact filter components.

[0026] Compared with the prior art, the present invention has the following beneficial effects: The gas dust content measuring device can accurately collect and calculate the dust content in the gas per unit volume, thereby calculating the dust content in the gas flowing in the gas pipeline. When detecting the dust content in the gas pipeline, the combination of a regulating valve, a flow control valve, and a wet gas flowmeter can accurately calculate the total volume of the measured gas. The three-stage filter assembly can disperse the pressure of the pressurized gas entering the filter unit, preventing the conventional filter membrane from rupturing due to excessive gas impact pressure. During the gas sampling process, data deviation will not occur due to gas retained in the sampling tube, thus solving the measurement error problems caused by the fragility of the filter membrane and irregular sampling position in traditional devices. The device has a compact structure, easy operation, low production cost, detection accuracy of up to 0.1mg, and repeatability error of less than 5%. For enterprises that are unable to purchase precision instruments for measurement, this device effectively solves the problem of inconvenient detection of gas dust content in pipelines faced by existing enterprises.

[0027] The entire measurement method is easy to operate, highly versatile, and has a flexible collection method. It also solves the problem that traditional devices have lax requirements on the location of sampling points and that the sampling tubes are prone to residual moisture or gas, which may lead to data deviation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 is a cross-sectional view of the filter unit of the present invention; In the figure: 1. Metering unit; 11. Wet gas flow meter; 2. Silicone hose; 3. Filter unit; 31. Dustproof shell; 311. Upper shell; 312. Lower shell; 313. Exhaust hole; 314. Storage groove; 315. Diversion hole; 32. Three-stage filter assembly; 321. Rubber gasket; 322. Metal filter mesh; 323. Filter membrane; 4. Sampling unit; 41. Sampling tube; 42. Regulating valve; 5. Gas pipeline; 6. Solid metal plate structure;. DETAILED DESCRIPTION

[0029] Below, the present application is further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0030] In the description of this application, it should be understood that the terms "up", "down", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on this application.

[0031] The terms "first," "second," and the like in this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0032] like Figure 1As shown, a gas dust content measuring device includes a gas pipeline 5, a gas dust extraction device is provided on one side of the gas pipeline 5, and the gas dust extraction device includes a sampling unit 4, a filter unit 3, a metering unit 1 and several silicone hoses 2. The sampling unit 4 includes a stainless steel sampling tube 41 welded at one end to the gas pipeline 5 and a regulating valve 42 provided on the sampling tube 41; the filter unit 3 includes a dustproof shell 31 and a three-stage filter assembly 32 stacked in the dustproof shell 31; the metering unit 1 includes a wet gas flowmeter 11, and the inlet and outlet of the dustproof shell 31 are respectively connected in series with the regulating valve 42 and the wet gas flowmeter 11 through the silicone hose 2.

[0033] Further improvement is as follows: Figure 2 As shown, the three-stage filter assembly 32 includes a stacked metal filter 322 and a filter membrane 323, and a rubber gasket 321 arranged on the outside of the metal filter 322 and the filter membrane 323. The metal filter 322 is located on the air inlet side of the dustproof shell 31.

[0034] Through the combination of the metal filter mesh 322, the filter membrane 323 and the rubber gasket 321, the pressurized gas entering the filter unit 3 can achieve the purpose of dispersing the airflow pressure, preventing the filter membrane 323 from rupturing due to excessive gas impact pressure, so that the dust in the gas can be filtered more effectively, and at the same time, particles of different particle sizes are intercepted to prevent particles from rebounding and affecting the measurement accuracy.

[0035] A further improvement is that the pore size of the filter membrane 323 is 0.45 μm, and the metal filter mesh 322 is made of 304 stainless steel with a mesh size of ≥200 meshes.

[0036] The filter is made of 304 stainless steel with a mesh size of ≥200. When the pressurized gas flows out, it is first effectively divided by the 304 stainless steel filter, which can make the airflow softer and more dispersed, and will not directly impact the filter membrane 323. At the same time, it intercepts particles of different sizes and can better prevent the impact and rebound of particles without damage. The pore size of the filter membrane 323 is 0.45μm, which can effectively filter the dust in the gas.

[0037] A further improvement is that the rubber gasket 321 adopts an oil-resistant rubber gasket 321.

[0038] Since many gases contain oil molecules, for example, the gas in the air compressor pipeline contains lubricating oil molecules, conventional rubber rings themselves have the special effect of absorbing oil, which can easily cause the oil molecules to adhere and decompose, resulting in the rubber ring being unable to perform a sealing function, making it impossible to effectively filter the dust in the gas, affecting the measurement accuracy. Therefore, the rubber gasket 321 uses an oil-resistant rubber gasket 321, which can effectively avoid the adsorption of oil molecules and the impact on it, thereby ensuring the accuracy of the detection.

[0039] A further improvement is that the installation position of the sampling tube 41 is ≥1.5 times the pipe diameter away from the elbow or diameter change of the gas pipeline 5.

[0040] The principle is that when gas flows in a pipeline, elbows or diameter changes will change the flow direction and speed of the gas, causing the gas to produce unstable flow states such as eddies and turbulence. These unstable airflows will make the dust distribution in the pipeline uneven. For example, outside the elbow, the gas flow rate increases, and dust may accumulate due to centrifugal force. At the diameter change, the gas pressure fluctuates due to the change in cross-section, and dust may also accumulate or disperse locally. If the sampling tube 41 is installed at these locations, the collected gas sample will not represent the actual dust content in the pipeline as a whole, resulting in deviations in the measurement data. The sampling tube 41 is installed at a distance of ≥1.5 pipe diameters from the pipe elbow or diameter change because after flowing through this distance, the gas has enough space to restore a stable laminar state, reducing eddy interference and making the dust distribution in the pipeline relatively uniform. At this time, the collected sample can more accurately reflect the dust content of the gas in the pipeline.

[0041] A further improvement is that the length of the silicone hose 2 is no more than 15 cm and the inner wall is polished.

[0042] The detected air pressure flow rate is generally around 3.5~4L / min. If the length of the silicone hose 2 is too long, dust may be easily adsorbed on the hose, resulting in deviation in the analysis data. After trial and error, it was found that when the length of the silicone hose 2 is controlled within 15cm and the inner wall is polished, this phenomenon can be effectively avoided, allowing dust to flow better along the silicone hose 2.

[0043] A further improvement is that the wet gas flow meter 11 has a measuring range of 0.5 m³ / h and a built-in temperature compensation module; the wet gas flow meter 11 adjusts the gas flow rate to 3.5-4 L / min through the regulating valve 42.

[0044] The wet gas flowmeter 11 can display the accumulated flow in real time. Since the flowmeter is filled with water, the flow rate will change with the temperature. When the temperature changes too much, the flow detection is prone to inaccurate problems, which will lead to the final detection results. Therefore, by adding a built-in temperature compensation module, it is possible to ensure that the temperature is constant during the measurement process, thereby ensuring the accuracy of the test results. Adjusting the gas flow rate to 3.5-4 L / min can avoid the problem of dust data deviation in the gas caused by the retention of liquid and gas in the sampling tube 41.

[0045] Further improvement is that the dustproof shell 31 includes a conical upper shell 311 and a lower shell 312, and the upper shell 311 and the lower shell 312 are connected by threads. A conical guide hole 315 is provided in the upper shell 311, and the connecting end of the lower shell 312 is provided with an inwardly recessed receiving groove 314, and the bottom of the receiving groove 314 is provided with an exhaust hole 313. The three-stage filter assembly 32 is installed in the receiving groove 314 and is pressed by the upper shell 311.

[0046] The entire three-stage filter assembly 32 is fixed to the storage groove 314 on the lower shell 312 by a threaded buckle, and the metal filter 322 is located on the outside of the storage groove 314. The bottom of the filter membrane 323 contacts the bottom of the storage groove 314 through the rubber gasket 321, and the outer side of the metal filter 322 is positioned by pressing the rubber gasket 321 against the upper shell 311. The conical guide hole 315 located in the upper shell 311 can allow the dust-containing gas to quickly diffuse to the guide hole 315 after entering. 5, thereby preventing airflow concentration from damaging the filter membrane 323 and reducing the filtration efficiency. The airflow first contacts the metal filter 322, thereby blocking particulate matter in the airflow and preventing damage to the filter membrane 323. The receiving groove 314 in the lower shell 312 is a stepped groove structure. After a large amount of air flows through the filter membrane 323, it can be buffered in the receiving groove 314 at the bottom of the filter membrane 323, thereby allowing the airflow to have sufficient time to flow out from the exhaust hole 313. A further improvement is that the middle position of the metal filter 322 facing the inlet of the guide hole 315 is a solid structure. When the strongest straight airflow hits the metal filter 322, this part of the airflow will rebound after contacting the solid part, thereby avoiding the damage of the bottom filter membrane 323 due to excessive airflow in the middle area, especially when the metal filter 322 adopts an upwardly protruding conical solid metal plate structure 6, when the airflow hits the metal filter 322, the conical solid metal plate can play a guiding role, which effectively ensures the division of the airflow and realizes the diversion of the airflow, avoiding the internal air pressure chaos caused by the rebound of the airflow. Among them, the diameter of the conical solid metal plate is 0.9~1.2 times the minimum diameter of the air inlet. The smaller it is, the better while ensuring that the filter membrane 323 will not be damaged. It can better ensure the filtration efficiency while dispersing the airflow pressure and preventing the filter membrane 323 from rupturing. The dustproof shell 31 is a detachable structure, and both ends are connected by a silicone hose 2, so that the filter unit 3 can be directly transferred to the dryer for constant weight drying to avoid secondary contamination.

[0047] In actual operation, it specifically includes: (1) Device installation: The gas dust extraction device is installed in the straight section of the gas pipeline 5, and a stainless steel sampling tube 41 is installed at a position more than 1.5m away from the elbow. The front end of the sampling tube 41 is provided with a sampling port with a regulating valve 42 to ensure stable and representative airflow.

[0048] Use two 15 cm long silicone hoses 2 with smooth inner walls to connect the stainless steel sampling tube 41 to the outer port of the upper shell 311 connected to the filter unit 3, and connect the wet gas flowmeter 11 to the outer port of the lower shell 312 connected to the filter unit 3 to complete the assembly of the various units of the device, ensuring that the gas drawn out of the stainless steel sampling tube 41 is filtered through the metal filter mesh 322 and filter membrane 323 in the dustproof shell 31 before being discharged, reducing the adsorption of dust in the gas during the transmission process during the gas discharge process.

[0049] (2) Sampling operation Slowly open the regulating valve 42, and the gas in the gas pipeline 5 is drawn out through the stainless steel sampling tube 41, and then passes through the filter unit 3 and the wet gas flow meter 11, and finally discharged to the outside. In this process, the dust in the gas is effectively intercepted and stored by the filter unit 3.

[0050] The regulating valve 42 is opened until the gas flow rate is stably controlled at 3.8 L / min. Sampling is continued until the weight gain of the filter membrane 323 reaches or exceeds 2 mg. Then, the valve is closed and the reading V2 (L) of the wet gas flow meter 11 is recorded. At the same time, the reading V1 (L) of the wet gas flow meter 11 before the test is recorded.

[0051] (3) Sample processing and measurement After the sampling is completed, the flow regulating valve 42 is closed, and then the filter unit 3 is disassembled.

[0052] Transfer the filter unit 3 directly to a desiccator containing color-changing silica gel, open it, and dry it at 105°C for 2 hours. After cooling, weigh the filter unit 3 multiple times until the difference between the two weighings is ≤ 0.3 mg. Record the mass m1 (g) at this point to ensure that the filter membrane 323 assembly has reached a stable mass. During this process, use tweezers to move the tertiary filter assembly 323 when necessary.

[0053] The dried filter unit 3 is measured using an integrated drying weighing instrument, and the weight m2 (g) of the filter unit 3 after the experiment is recorded.

[0054] (IV) Data calculation and result determination According to the dust concentration calculation formula: Dust concentration =

[0055] (Unit: mg / L), where m2 is the weight of the filter unit after the experiment and m1 is the weight of the filter unit before the experiment, in g.

[0056] v2 is the reading of the wet gas flow meter after the test, and v1 is the reading of the wet gas flow meter before the test, and the unit is L.

[0057] Substitute the recorded data into the formula for calculation to obtain the dust content of the gas in the gas pipeline 5. According to the relevant environmental protection standards and enterprise requirements, the calculation results are judged to determine whether the exhaust gas emissions meet the standards.

[0058] For example, taking the air compressor delivery pipeline as an example, record the initial flowmeter volume V1 (L) as 25L, record the final flowmeter volume as 679L, and record V2; the constant weight standard is that when using a medium flow or low flow sampler, the difference in mass between two weighings of the same filter membrane 323 should be less than 0.04mg (one hundred thousandth of a balance); the average of the two weighing results is used as the weighing value of the filter unit 3. Before the experiment, the constant weight of the three-stage filter component 32 was measured to be 25.4200g for the first time and 25.4202g for the second time. After the experiment, the constant weight of the filter unit 3 was 25.4246g for the first time and 25.4247g for the second time. The dust concentration calculation formula is: The dust content of the gas in the gas pipeline was found to be 0.007 mg / L, the detection accuracy reached 0.1 mg level, and the repeatability error was less than 5% after multiple tests, which effectively solved the problem that the traditional device had no strict requirements on the sampling point location and the sampling tube was prone to residual moisture or gas, resulting in data deviation.

[0059] The above-mentioned embodiments are only preferred embodiments of the present application and cannot be used to limit the scope of protection of the present application. Any non-substantial changes and replacements made by technicians in this field based on the present application shall fall within the scope of protection required by the present application.

Claims

1. A gas dust content measuring device, comprising a gas pipeline (5), characterized in that: A gas dust extraction device is provided on one side of the gas pipeline (5), and the gas dust extraction device comprises a sampling unit (4), a filtering unit (3), a metering unit (1) and a plurality of silicone hoses (2). The sampling unit (4) comprises a stainless steel sampling tube (41) welded at one end to the gas pipeline (5) and a regulating valve (42) provided on the sampling tube (41); the filtering unit (3) comprises a dustproof shell (31) and a three-stage filter assembly (32) stacked in the dustproof shell (31); the metering unit (1) comprises a wet gas flow meter (11), and the inlet and outlet of the dustproof shell (31) are respectively connected in series with the regulating valve (42) and the wet gas flow meter (11) through the silicone hose (2).

2. A gas dust content measuring device according to claim 1, characterized in that: The three-stage filter assembly (32) comprises a stacked metal filter screen (322) and a filter membrane (323), and a rubber gasket (321) arranged outside the metal filter screen (322) and the filter membrane (323); the metal filter screen (322) is located on one side of the air inlet of the dustproof housing (31).

3. A gas dust content measuring device according to claim 2, characterized in that: The pore size of the filter membrane (323) is 0.45 μm, and the metal filter (322) is made of 304 stainless steel with a mesh size of ≥200 meshes.

4. A gas dust content measuring device according to claim 2, characterized in that: The rubber gasket (321) is an oil-resistant rubber gasket (321).

5. The gas dust content measuring device according to claim 1, characterized in that: The length of the silicone hose (2) is no more than 15 cm, and the inner wall is polished.

6. A gas dust content measuring device according to claim 1, characterized in that: The wet gas flow meter (11) has a measuring range of 0.5 m³ / h and a built-in temperature compensation module.

7. A method for measuring dust content in gas, characterized by: The equipment involved in the measurement method includes the gas dust content measuring device, tweezers, a dryer and a dry weighing instrument as described in claims 1 to 6, and the measurement method includes: S1. After drilling a hole in the straight section of the gas pipeline (5), install a stainless steel sampling tube (41) with a regulating valve (42); S2. Connect the filter unit (3) to the sampling port of the stainless steel sampling tube (41) through the silicone hose (2); S3, connecting the wet gas flow meter (11) to the outlet end of the filter unit (3) through the silicone hose (2); S4. Slowly open the regulating valve (42) until the wet gas flow meter (11) reaches 3.5-4 L / min, so that the gas in the gas pipe (5) is filtered by the filter unit (3) and then discharged from the outlet of the wet gas flow meter (11). The dust in the gas is filtered and collected by the three-stage filter assembly (32) in the filter unit (3); and the gas flow rate per unit volume is calculated by the wet gas flow meter (11); S5. When the exhaust gas from the wet gas flow meter (11) reaches the set target, quickly close the regulating valve (42) and remove the filter unit (3); S6. After opening the dust cover (31) in the filter unit (3), place the entire unit in a dryer and dry it at a constant temperature of 105° C. for 2 hours. After cooling, weigh it until the mass is stable, ensuring that the difference between the two weighings is ≤0.3 mg, and record m1; S7. Place the dryer on a dry weighing instrument to measure and calculate the dust content. Calculate the dust content of the gas in the gas pipeline (5) based on the dust weight and the gas flow recorded by the wet gas flow meter (11).

8. The method for measuring dust content in gas according to claim 7, characterized in that: The flow rate is adjusted to 3.8 L / min by the regulating valve (42), and the valve is closed after sampling until the filter membrane (323) gains weight ≥ 2 mg, and the flow meter reading V (L) is recorded.

9. The method for measuring dust content in gas according to claim 8, characterized in that: The dust concentration calculation formula is: , Wherein, m2 is the weight of the membrane assembly after the experiment, m1 is the weight of the membrane assembly before the experiment, and the unit is g. v2 is the reading of the wet gas flow meter (11) after the experiment, and v1 is the reading of the wet gas flow meter (11) before the experiment, and the unit is L.

10. The method for measuring dust content in gas according to claim 7, characterized in that: The tweezers are antistatic tweezers to prevent the filter membrane (323) from absorbing impurities during weighing.

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