An online gas sampling and analysis device and method

Abstract

This invention relates to the field of industrial process gas monitoring technology, specifically to an online gas sampling and analysis device and method. The device includes an integrated pretreatment unit, a gas analysis and detection device, and a piping system. The pretreatment unit employs a two-stage dust removal structure combining cyclone inertial separation and electrostatic dust removal to achieve efficient dust removal. Subsequently, the gas is temperature-controlled by a microchannel heat exchange module and then separated into gas and liquid by a vacuum diffusion-welded integrated superhydrophobic membrane. The method utilizes an innovatively designed pretreatment unit, combining two-stage dust removal with microchannel heat exchange and temperature control to prevent condensation from mixing with dust and causing filter blockage, thus preventing the loss of water-soluble gases and improving detection accuracy. Furthermore, the modular integrated design of this invention reduces system pressure loss and energy consumption, facilitates maintenance, and is suitable for long-term online monitoring in complex industrial environments such as high temperature, high humidity, and high dust levels.

Description

Technical Field

[0001] This invention relates to the field of industrial process gas monitoring technology, specifically to an online gas sampling and analysis device and method. Background Technology

[0002] The information disclosed in the background section of this invention is intended only to enhance the understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] In the field of industrial process gas monitoring technology, the stable operation of online gas sampling and analysis devices highly depends on the pretreatment stage, which is the core support for ensuring the system maintains accurate monitoring performance over the long term and reducing the failure rate. The core function of the pretreatment stage is to purify and regulate the operating conditions of the collected gas, specifically covering key operations such as particulate matter removal, separation of interfering components, and temperature and pressure control. Therefore, a high-performance pretreatment system can significantly extend the lifespan of the analyzer, reduce maintenance frequency, and lower operating costs, thereby greatly improving the automation level and practical availability of the entire online analysis system.

[0004] Although existing technologies have improved pretreatment processes through optimization methods such as multi-stage filtration and gradient dehumidification, insurmountable technical bottlenecks remain. Current mainstream pretreatment processes generally employ a common serial mode of dehumidification followed by fine filtration, or dust removal, dehumidification, and secondary dust removal. However, this approach reveals significant drawbacks in actual operation: during compressor-based refrigeration and dehumidification, the generated condensate easily mixes with residual dust particles in the gas, forming a sticky, muddy mixture. This mixture quickly adheres to the filter surface in subsequent fine filtration stages, drastically reducing the effective filtration area and significantly shortening the clogging cycle. This not only increases maintenance workload and consumable costs but may also disrupt monitoring continuity due to frequent downtime for maintenance. Furthermore, the series connection of multi-stage processing units significantly increases the cumulative pressure loss of the gas flowing through the entire pretreatment system. To ensure the stability of the gas sampling flow rate, a high-power vacuum pump must be configured to provide driving force, directly resulting in a high energy consumption ratio, which does not meet the current industrial energy conservation and emission reduction requirements.

[0005] Therefore, overcoming the inherent limitations of existing pretreatment processes and solving problems such as easy clogging of filter elements and excessive system energy consumption has become an important technical direction for improving the performance of online gas sampling and analysis devices. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention aims to provide an online gas sampling and analysis device and method, which aims to solve the problem of lack of synergistic optimization and superposition of flow resistance and energy consumption caused by the separate design of dust removal, dehumidification and temperature control units in the pretreatment process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] An online gas sampling and analysis device includes a housing, in which a pretreatment system, a gas analysis and detection device, a gas pipeline system, and control components are installed;

[0009] The pretreatment system includes an integrated pretreatment unit, which includes a dust removal module, and a deep treatment module is sealed on the top of the dust removal module.

[0010] The dust removal module includes a swirling inertial separation shell, a swirling separation chamber inside the swirling inertial separation shell, an air inlet tangentially arranged on the top side wall of the swirling separation chamber, a cylindrical airflow purification cylinder arranged at the top center of the swirling separation chamber, a dust outlet arranged at the bottom center of the swirling separation chamber, a dust collection box sealed and installed at the dust outlet, and an electrostatic dust removal component installed at the center of the airflow purification cylinder.

[0011] The deep processing module includes an installation cylinder, inside which a microchannel heat exchange module is installed. The microchannel heat exchange module includes an integrally formed heat exchange body. The heat exchange body has several microchannel pores and heat exchange channels, separated by a heat exchange core plate. The heat exchange core plate penetrates the heat exchange body, allowing the microchannel pores to communicate with the upper and lower ends of the heat exchange body. The upper and lower ends of the heat exchange body also have inlet and outlet water channels that communicate with the heat exchange channels. The inlet and outlet water channels are respectively connected to an inlet pipe and an outlet pipe. A superhydrophobic membrane is integrally formed on the upper end of the heat exchange body using vacuum diffusion welding.

[0012] The top of the deep processing module is sealed with a gas collection hood, which is connected to the gas analysis and detection device and the gas outlet in sequence through a gas pipeline system.

[0013] Preferably, the top of the swirling inertial separation shell is a conical cylinder, and the airflow purification cylinder is integrally formed and disposed at the bottom center of the swirling inertial separation shell;

[0014] A particulate dust spray nozzle is integrally formed below the center of the airflow purification cylinder. The particulate dust spray nozzle is connected to the dust outlet, and an airflow outlet is provided between the airflow purification cylinder and the particulate dust spray nozzle.

[0015] Preferably, the gas pipeline system includes a first electromagnetic three-way valve connected to the inlet and calibration port. The first electromagnetic three-way valve is also connected in sequence to a power pump, a pressure regulating valve and a working flow meter through a pretreatment unit. The working flow meter is connected to the inlet of the gas analysis and detection device. The outlet of the gas analysis and detection device is connected to the outlet through a second electromagnetic three-way valve and a pipeline.

[0016] The second electromagnetic three-way valve is also connected to the inlet end of the backflush flow meter, and the outlet end of the backflush flow meter is connected to the outlet end of the gas collection hood of the pretreatment unit through a pipeline.

[0017] Preferably, the air inlet is also connected to a direct detection branch, and a third electromagnetic three-way valve and a fourth electromagnetic three-way valve are respectively provided at both ends of the direct detection branch; the air collection hood outlet of the pretreatment unit is also connected to a direct outlet branch, and a fifth electromagnetic three-way valve and a sixth electromagnetic three-way valve are respectively provided at both ends of the direct outlet branch.

[0018] Preferably, the outer wall of the airflow purification cylinder is provided with a swirl guide plate;

[0019] The lower end of the airflow purification cylinder is designed with a constricted opening smaller than that of the particulate dust spray cylinder.

[0020] Preferably, the gas collecting hood, heat exchange body and swirling inertial separation shell are all connected by flange sealing to form an integrated structure.

[0021] In addition, to better solve the above-mentioned technical problems, the present invention also provides the following technical solutions:

[0022] A method for online gas sampling and analysis using any of the above-mentioned online gas sampling and analysis devices includes a gas pretreatment method, wherein the gas pretreatment method includes the following steps:

[0023] S1, Swirl inertial separation: The gas to be tested entering through the air inlet coarsely separates large dust particles in the conical annular swirl separation chamber;

[0024] S2, Electrostatic dust removal: The gas to be tested, after coarse separation, enters the airflow purification cylinder from the airflow outlet located in the center of the cyclone separation chamber. The fine dust is further separated by the electrostatic dust removal components in the airflow purification cylinder.

[0025] S3, Microchannel heat exchange and temperature control: The gas to be tested, after being subdivided, enters from the microchannel vents on the bottom side of the heat exchange body and exchanges heat with the process cooling water in the heat exchange channel, so that the temperature of the gas to be tested is suitable for detection.

[0026] S4, superhydrophobic membrane dehumidification: The gas to be tested, after coarse separation, fine separation and temperature control, removes liquid water and oil mist through the superhydrophobic membrane on the top side of the heat exchanger.

[0027] Preferably, the heat exchanger body is made of titanium alloy, and the thickness of the heat exchanger core plate inside it is 20-30μm; the superhydrophobic membrane is made of polytetrafluoroethylene, and the pore size of the superhydrophobic membrane is 0.2-0.4μm.

[0028] The present invention has at least the following beneficial effects:

[0029] Compared to traditional serial pretreatment methods that result in condensate and residual dust mixing into a mud-like substance that clogs the fine filter cartridge, and the high cumulative flow resistance caused by multi-stage series units, requiring a high-power vacuum pump and resulting in high energy consumption, this invention, on the one hand, thoroughly and effectively pre-emptively removes dust. Before dehumidification, it removes the vast majority of dust through two-stage high-efficiency dust removal using cyclone inertial separation and electrostatic dust removal, ensuring that the dust content of the gas entering the dehumidification stage is extremely low. On the other hand, it cools the gas through a microchannel heat exchange module, preventing the generation of condensate. The combination of these two methods eliminates the formation of mud-like substances at the source. Then, it employs a high-efficiency microchannel heat exchange and superhydrophobic membrane dehumidification for synergistic treatment, ensuring the treatment effect while minimizing the impact of the treatment process on the gas flow rate and response time.

[0030] Meanwhile, by integrating key pretreatment units into a compact module, the gas flow path is significantly shortened, thereby greatly reducing system flow resistance. This efficient dust removal and compact design reduce pumping power and energy consumption. Furthermore, the modular and maintainable design of this invention greatly improves ease of operation and maintenance. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the internal structure of the depth processing module;

[0033] Figure 3 This is a structural diagram of the dust removal module;

[0034] Figure 4 This is a schematic diagram of the cross-sectional structure of the heat exchanger body;

[0035] Figure 5 This is a schematic diagram of the bottom structure of the heat exchanger body;

[0036] Figure 6 This is a schematic diagram of a gas pipeline system.

[0037] The attached figures are labeled as follows:

[0038] 100. Housing; 200. Dust removal module; 210. Cyclone separation chamber; 211. Dust collection box; 212. Air inlet; 220. Airflow purification cylinder; 221. Electrostatic dust removal assembly; 222. Cyclone guide plate; 230. Particulate dust spray nozzle; 240. Airflow outlet; 250. Contraction port; 260. Top of cyclone inertial separation shell; 300. Deep processing module; 310. Heat exchanger body; 311. Heat exchanger core plate; 312. Microchannel vents; 313. Heat exchange flow... 314. Superhydrophobic membrane; 320. Inlet pipe; 330. Outlet pipe; 400. Gas collection hood; 411. First solenoid three-way valve; 412. Power pump; 413. Pressure regulating valve; 414. Working flow meter; 415. Second solenoid three-way valve; 416. Backflush flow meter; 417. Fifth solenoid three-way valve; 418. Sixth three-way solenoid three-way valve; 419. Third solenoid three-way valve; 420. Fourth solenoid three-way valve; 500. Air outlet; 600. Control components. Detailed Implementation

[0039] The present invention will be further described below with reference to specific embodiments and accompanying drawings.

[0040] Example 1

[0041] Figures 1 to 6 An online gas sampling and analysis device is presented, including a housing 100, within which a pretreatment system, a gas analysis and detection device, its gas pipeline system, and a control component 600 are installed. The housing 100 serves as the mounting carrier and protective shell for the entire device, providing a closed operating environment for the internal pretreatment system and gas analysis and detection device, reducing interference from external dust and temperature fluctuations, and facilitating integrated equipment layout and on-site installation.

[0042] The pretreatment system includes an integrated pretreatment unit, which is crucial for ensuring the accuracy of gas analysis and is used to achieve graded purification and operating condition control of the gas. Specifically, it includes a dust removal module 200, and a deep processing module 300 is sealed and installed on the top of the dust removal module 200.

[0043] The dust removal module 200 includes a swirling inertial separation shell, and a swirling separation chamber 210 is provided inside the swirling inertial separation shell. The swirling separation chamber 210 serves as the basic structure of the dust removal module 200, and forms a closed swirling separation chamber 210 inside, providing physical space for gas swirling separation.

[0044] The top sidewall of the cyclone separation chamber 210 is tangentially provided with an air inlet 212. Gas enters tangentially from the top sidewall of the cyclone separation chamber 210, forming a high-speed rotating airflow in the chamber. The centrifugal inertial force is used to throw large dust particles of about 5μm or larger toward the chamber wall, thereby achieving coarse dust removal and reducing the dust load of subsequent fine processing.

[0045] A cylindrical airflow purification tube 220 is provided at the top center of the cyclone separation chamber 210. Located at the top center of the cyclone separation chamber 210, it serves as the channel for gas to enter the next processing stage. At the same time, its outer wall can guide the rotating airflow to flow stably and avoid eddy current loss.

[0046] A dust outlet is located at the center of the bottom of the cyclone separation chamber 210, and a dust collection box 211 is sealed and installed at the dust outlet. An electrostatic dust removal component 221 is installed at the center of the airflow purification cylinder 220. The electrostatic dust removal component 221 captures the fine dust remaining after cyclone separation, such as PM2.5 particles, through electrostatic adsorption, achieving fine dust removal. The dust separated by cyclone separation and electrostatic dust removal settles through the dust outlet and is collected by the dust collection box 211. The dust collection box 211 can be threadedly connected to the dust outlet, ensuring a good seal and facilitating disassembly.

[0047] The deep processing module 300 includes an installation cylinder, in which a microchannel heat exchange module is installed. The microchannel heat exchange module includes an integrally formed heat exchange body 310, which helps to reduce leakage points and has both corrosion resistance and high thermal conductivity. The heat exchange body 310 has several microchannel vents 312 and heat exchange channels 313. The microchannel vents 312 and heat exchange channels 313 are separated by a heat exchange core plate 311. This helps to increase the overall effective heat exchange area and maximize heat exchange efficiency, thereby achieving stable and precise control of gas temperature, such as cooling high-temperature gas to the appropriate temperature of the analyzer or heating low-temperature gas to above the dew point.

[0048] The heat exchange core plate 311 is disposed through the heat exchange body 310, so that the microchannel vents 312 are connected to the upper and lower ends of the heat exchange body 310. The upper and lower ends of the heat exchange body 310 are also provided with inlet channels and outlet channels that are connected to the heat exchange channels 313. The inlet channels and outlet channels are connected to the inlet pipe 320 and the outlet pipe 330, respectively. The upper end of the heat exchange body 310 is integrally formed with a superhydrophobic membrane 314 by vacuum diffusion welding. This avoids the leakage problem caused by traditional bonding. Because the pre-dust removal is thorough, there is no dust adhering to the membrane surface, which solves the pain point of dust and condensate mixing and clogging the filter element in the traditional dehumidification process.

[0049] The core principle of vacuum diffusion welding integrated superhydrophobic film 314 is as follows: In a vacuum environment, eliminating interference from air, moisture, and other impurities, a certain temperature and pressure are applied to the tightly bonded surfaces of dissimilar or homogeneous materials. This causes plastic deformation of the contact surfaces, breaking the surface oxide layer and promoting the diffusion and migration of material atoms across the interface. Ultimately, a continuous and dense metallurgical bonding layer is formed through recrystallization. This process requires no filler solder and can achieve seamless bonding between substrates such as titanium alloys and metal-based superhydrophobic film 314, while preserving the physical properties and microstructure of the substrate itself. This provides crucial support for the high-efficiency heat exchange, reliable dehumidification, and low flow resistance characteristics of the deep processing module 300.

[0050] The specific implementation process is as follows: The surface of the heat exchanger body 310 to be welded is precision machined to a roughness ≤ Ra0.8μm to remove burrs and oxide layers; then it is cleaned to remove oil and impurities, and finally dried under inert gas protection to avoid secondary oxidation. Next, the superhydrophobic film 314 is treated. In actual operation, a composite structure of a metal-based support layer and a polytetrafluoroethylene coating can also be used. The metal-based support layer can be made of stainless steel to ensure welding feasibility. Finally, the pretreated heat exchanger body 310 and the superhydrophobic film 314 are heated in a vacuum environment to fuse them.

[0051] During the heating process, the temperature is slowly increased to the process temperature at a rate of 5-10℃ / min. Considering the material characteristics of the titanium alloy and the superhydrophobic 314 metal support layer, the process temperature is controlled at 800-950℃ to avoid decomposition of the superhydrophobic 314 coating due to high temperature while ensuring sufficient atomic activity at the metal contact surface. It is important to note that after reaching the process temperature, appropriate heat and pressure holding operations are required to further eliminate gaps. High temperatures enable metal atoms to obtain sufficient diffusion energy, achieving interfacial atomic fusion through grain boundary migration and dislocation movement, forming a continuous bonding layer. The heat and pressure holding time is adjusted according to the bonding area, typically 30-60 minutes, to ensure sufficient diffusion.

[0052] In addition, after diffusion is complete, heating is stopped, and the furnace is cooled to below 200°C in a vacuum environment at a cooling rate of ≤5°C / min to avoid thermal stress caused by rapid cooling, which could lead to cracking of the microchannels or membrane structure. After cooling to room temperature, the pressure is released, and the integrally molded component is removed.

[0053] The top of the deep processing module 300 is sealed with a gas collecting hood 400, which is connected to the gas analysis and detection device and the gas outlet 500 via a gas pipeline system. The gas collecting hood 400 is used to collect the processed clean gas, reduce airflow eddies and pressure loss, and stably deliver it to the gas analysis and detection device. The gas collecting hood 400, the heat exchange body 310, and the swirling inertial separation shell are all connected as an integrated structure with flange sealing, ensuring both sealing and strength.

[0054] To further ensure a stable swirling coarse separation effect, the top 260 of the swirling inertial separation shell is set as a conical cylinder. The conical structure can also guide the gas entering the swirling separation chamber 210 to form a more stable and more reasonable spiral downward airflow, thereby reducing the turbulent disturbance of the airflow during rotation, making the centrifugal force distribution more uniform, and ensuring that large particles are effectively thrown towards the cylinder wall under the action of centrifugal force and slide down the conical wall to the dust outlet.

[0055] The airflow purification cylinder 220 is integrally formed and located at the bottom center of the swirling inertial separation shell; a particulate dust spray cylinder 230 is integrally formed below the center of the airflow purification cylinder 220, the particulate dust spray cylinder 230 leads into the dust outlet, and an airflow outlet 240 is provided between the airflow purification cylinder 220 and the particulate dust spray cylinder. The integral forming enhances the overall structural strength and can withstand high-frequency vibration or airflow impact in industrial environments.

[0056] To further enhance the stable flow of the rotating airflow, a swirl guide plate 222 is provided on the outer wall of the airflow purification cylinder 220.

[0057] To ensure effective dust spraying and prevent fine dust from entering the cyclone separation chamber 210 through the airflow outlet 240 after backflushing, the lower end of the airflow purification cylinder 220 is designed with a smaller diameter than the constriction port 250 of the particulate dust spray cylinder 230. At the same time, this design also increases the space at the airflow outlet 240, which is conducive to the airflow entering the airflow purification cylinder 220 more smoothly, thereby improving the processing efficiency.

[0058] Gas piping systems such as Figure 6 As shown, the system includes a first electromagnetic three-way valve 411 connected to the air inlet 212 and the calibration port. The first electromagnetic three-way valve 411 is also connected in sequence to a power pump 412, a pressure regulating valve 413, and a working flow meter 414 via a pretreatment unit. The working flow meter 414 is connected to the air inlet of the gas analysis and detection device. The air outlet of the gas analysis and detection device is connected to the air outlet 500 via a second electromagnetic three-way valve 415 and a pipeline, forming a detection gas path system. The control component 600 includes a controller, switches, knobs, etc., mounted on the housing 100 for controlling the gas pipeline system.

[0059] The second electromagnetic three-way valve 415 is also connected to the inlet end of the backflushing flow meter 416, and the outlet end of the backflushing flow meter 416 is connected to the outlet end of the air collection hood 400 of the pretreatment unit through a pipeline, ensuring the smooth progress of backflushing cleaning. Backflushing can be used to periodically clean the electrostatic precipitator plates and membrane surface, extending the maintenance cycle.

[0060] To improve adaptability and ensure applicability to various personalized scenarios, the air inlet 212 is also connected to a direct detection branch, with a third electromagnetic three-way valve 419 and a fourth electromagnetic three-way valve 420 respectively installed at both ends of the direct detection branch; the outlet end of the gas collection hood 400 of the pretreatment unit is also connected to a direct outlet branch, with a fifth electromagnetic three-way valve 417 and a sixth electromagnetic three-way valve respectively installed at both ends of the direct outlet branch.

[0061] Example 2

[0062] To better address the aforementioned technical problems, the present invention also provides the following technical solutions:

[0063] A method for online gas sampling and analysis using any of the above-mentioned online gas sampling and analysis devices includes a gas pretreatment method, wherein the gas pretreatment method includes the following steps:

[0064] S1: Cyclone Inertial Separation: The dust-laden gas to be tested enters the conical annular cyclone separation chamber 210 tangentially through the inlet 212. The gas forms a high-speed rotating vortex within the chamber, generating a strong centrifugal force. Larger dust particles are thrown against the sidewall of the cyclone inertial separation shell under the action of centrifugal force, and guided by gravity and downward airflow, settle downwards along the conical wall. The settled large dust particles eventually fall into the sealed dust collection box 211 through the dust outlet at the bottom. The preliminarily purified gas converges towards the central area of ​​the separation chamber.

[0065] S2: Electrostatic Precipitation: The pre-purified gas enters the airflow purification cylinder 220 from the top center of the cyclone separation chamber 210 through the airflow outlet 240. The electrostatic precipitator 221 includes a high-voltage discharge electrode and a grounded dust collection electrode, generating an electric field inside the cylinder. Fine dust particles in the gas are charged in the electric field and adsorbed onto the dust collection electrode under the action of the electric field force. The adsorbed dust falls into the dust collection box 211 below through the particulate dust spray nozzle 230 under the action of gravity or periodic backflushing.

[0066] After passing through two stages of dust removal, the gas has extremely low dust content and flows upward into the deep treatment module 300. At this point, the gas has not yet come into contact with the condensate, and the dust has been basically removed.

[0067] S3: Microchannel Heat Exchange Temperature Control: The dust-removed gas enters through numerous microchannel vents 312 on the bottom side of the heat exchange body 310. Simultaneously, in this embodiment, process cooling water at 30–40℃ enters the heat exchange channel 313 through the water inlet channel. An extremely thin heat exchange core plate 311, 20–30 μm thick, efficiently separates the gas vents from the water-carrying heat exchange channel 313, creating a larger heat exchange area. In this embodiment, the heat exchange body 310 is made of titanium alloy; however, other more suitable materials can be used depending on the implementation requirements.

[0068] When the gas flows in the microchannel, its heat is quickly transferred to the flowing cooling water through the heat exchange core plate 311, or vice versa, depending on the process requirements. This enables precise regulation of the gas temperature, such as dropping it below the dew point or raising it to the required temperature. After heat exchange, the water is discharged through the outlet channel.

[0069] S4: Dehumidification using the superhydrophobic membrane 314: After temperature control, in this embodiment, taking the temperature drop below the dew point as an example, water vapor in the gas condenses into liquid water droplets. The gas carrying the water droplets continues to flow upward, reaching the polytetrafluoroethylene superhydrophobic membrane 314 with pores of 0.2-0.4 μm. The superhydrophobic membrane 314 has a strong repulsion for liquid water and a large contact angle, but allows gas molecules to pass through. Liquid water droplets cannot wet and pass through the membrane pores, and are blocked on the downstream side of the membrane, discharged into the dust collection box 211. Dry gas molecules pass smoothly through the superhydrophobic membrane 314 and enter the gas collection hood 400. Due to the pre-high-efficiency dust removal, the water condensed here is relatively clean and is not likely to form mud-like substances that clog the membrane.

[0070] Dry, clean gas at a suitable temperature is drawn out from the gas collection hood 400, and after pressure regulation and flow measurement in the gas pipeline system, it enters the gas analysis and detection device. The gas analysis and detection device can use existing technologies, such as spectrometers, chromatographs, and sensors, to analyze the composition or concentration of the gas to be tested. The analyzed waste gas is discharged or treated through the gas outlet 500.

[0071] The purpose of traditional condensation is to cool the gas below the dew point, causing gaseous water to condense into liquid water and be discharged, preventing liquid water from corroding sensors, clogging gas paths, or interfering with optical detection. However, the condensation process causes water-soluble gases such as SO2, NH3, and HCl to be lost with the condensate, resulting in compositional distortion, and the cooling efficiency is low, which is a major bottleneck causing system delays.

[0072] In this method, a microchannel heat exchange module replaces traditional condensation, rapidly cooling the high-temperature gas (around 150°C) to around 45°C without producing condensate, thus completely avoiding the risk of component distortion and the formation of viscous, muddy substances. The superhydrophobic membrane 314, with its pore size and surface superhydrophobicity, further blocks liquid water and oil mist. The pre-filter module 200, which performs coarse and fine dust separation, ensures no dust adhesion to the membrane surface, thereby guaranteeing the normal, stable, and efficient operation of the overall sampling, analysis, and detection.

[0073] In summary, this invention employs an innovative pretreatment unit with a unique structural design. Through two-stage dust removal combined with microfluidic heat exchange and temperature control, it avoids condensation and dust mixing, preventing filter clogging and loss of water-soluble gases, thus improving detection accuracy. Furthermore, the modular integrated design of this invention reduces system pressure loss and energy consumption, facilitates maintenance, and is suitable for long-term online monitoring in complex industrial environments such as high temperature, high humidity, and high dust levels.

[0074] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0075] The terms "upper," "lower," "outer," "inner," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish relative positional relationships and are not necessarily qualitative. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0076] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An online gas sampling and analysis device, comprising a housing, wherein a pretreatment system, a gas analysis and detection device, a gas pipeline system, and control components are installed inside the housing; characterized in that: The pretreatment system includes an integrated pretreatment unit, which includes a dust removal module, and a deep treatment module is sealed on the top of the dust removal module. The dust removal module includes a swirling inertial separation shell, a swirling separation chamber inside the swirling inertial separation shell, an air inlet tangentially arranged on the top side wall of the swirling separation chamber, a cylindrical airflow purification cylinder arranged at the top center of the swirling separation chamber, a dust outlet arranged at the bottom center of the swirling separation chamber, a dust collection box sealed and installed at the dust outlet, and an electrostatic dust removal component installed at the center of the airflow purification cylinder. The deep processing module includes an installation cylinder, inside which a microchannel heat exchange module is installed. The microchannel heat exchange module includes an integrally formed heat exchange body. The heat exchange body has several microchannel pores and heat exchange channels, separated by a heat exchange core plate. The heat exchange core plate penetrates the heat exchange body, allowing the microchannel pores to communicate with the upper and lower ends of the heat exchange body. The upper and lower ends of the heat exchange body also have inlet and outlet water channels that communicate with the heat exchange channels. The inlet and outlet water channels are respectively connected to an inlet pipe and an outlet pipe. A superhydrophobic membrane is integrally formed on the upper end of the heat exchange body using vacuum diffusion welding. The top of the deep processing module is sealed with a gas collection hood, which is connected to the gas analysis and detection device and the gas outlet in sequence through a gas pipeline system.

2. The online gas sampling and analysis device as described in claim 1, characterized in that: The top of the swirling inertial separation shell is set as a conical cylinder, and the airflow purification cylinder is integrally formed and set at the bottom center of the swirling inertial separation shell; A particulate dust spray nozzle is integrally formed below the center of the airflow purification cylinder. The particulate dust spray nozzle is connected to the dust outlet, and an airflow outlet is provided between the airflow purification cylinder and the particulate dust spray nozzle.

3. The online gas sampling and analysis device as described in claim 1, characterized in that: The gas pipeline system includes a first electromagnetic three-way valve connected to the inlet and calibration port. The first electromagnetic three-way valve is also connected in sequence to a power pump, a pressure regulating valve and a working flow meter through a pretreatment unit. The working flow meter is connected to the inlet of the gas analysis and detection device. The outlet of the gas analysis and detection device is connected to the outlet through a second electromagnetic three-way valve and a pipeline. The second electromagnetic three-way valve is also connected to the inlet end of the backflush flow meter, and the outlet end of the backflush flow meter is connected to the outlet end of the gas collection hood of the pretreatment unit through a pipeline.

4. The online gas sampling and analysis device as described in claim 3, characterized in that: The air inlet is also connected to a direct detection branch, and a third electromagnetic three-way valve and a fourth electromagnetic three-way valve are respectively provided at both ends of the direct detection branch; the outlet end of the gas collection hood of the pretreatment unit is also connected to a direct outlet branch, and a fifth electromagnetic three-way valve and a sixth electromagnetic three-way valve are respectively provided at both ends of the direct outlet branch.

5. The online gas sampling and analysis device as described in claim 2, characterized in that: The outer wall of the airflow purification cylinder is provided with a swirl guide plate; The lower end of the airflow purification cylinder is designed with a constricted opening smaller than that of the particulate dust spray cylinder.

6. The online gas sampling and analysis device as described in claim 2, characterized in that: The gas collecting hood, heat exchange body and swirling inertial separation shell are all connected by flange sealing to form an integrated structure.

7. A method for online gas sampling and analysis using any one of the online gas sampling and analysis devices according to claims 1-6, comprising a gas pretreatment method, characterized in that: The gas pretreatment method includes the following steps: S1, Swirl inertial separation: The gas to be tested entering through the air inlet coarsely separates large dust particles in the conical annular swirl separation chamber; S2, Electrostatic dust removal: The gas to be tested, after coarse separation, enters the airflow purification cylinder from the airflow outlet located in the center of the cyclone separation chamber. The fine dust is further separated by the electrostatic dust removal components in the airflow purification cylinder. S3, Microchannel heat exchange and temperature control: The gas to be tested, after being subdivided, enters from the microchannel vents on the bottom side of the heat exchange body and exchanges heat with the process cooling water in the heat exchange channel, so that the temperature of the gas to be tested is suitable for detection. S4, superhydrophobic membrane dehumidification: The gas to be tested, after coarse separation, fine separation and temperature control, removes liquid water and oil mist through the superhydrophobic membrane on the top side of the heat exchanger.

8. The method for online gas sampling and analysis using the online gas sampling and analysis device as described in claim 7, characterized in that: The heat exchanger body is made of titanium alloy, and the thickness of the heat exchanger core plate inside it is 20-30μm; the superhydrophobic membrane is made of polytetrafluoroethylene, and the pore size of the superhydrophobic membrane is 0.2-0.4μm.

Images