Micro water vapor removal device and method based on membrane permeation technology

Abstract

The application discloses a trace water vapor removal device and method based on a membrane permeation technology, relates to the technical field of online total sulfur analysis, and specifically comprises a membrane drying assembly, the membrane drying assembly comprises a middle-through exchange cavity, a top cover and a bottom cover which are constructed in an overall shell shape, and the middle-through exchange cavity is taken as the center, the top cover is fixed on the top of the middle-through exchange cavity through bolts, and the bottom cover is fixed on the bottom of the middle-through exchange cavity; the application adopts intelligent adjustment and a high-efficiency dehydration structure, the humidity of reaction gas is monitored in real time through a humidity sensor, data is fed back to an external controller, intelligent linkage adjustment of the opening size of the movable air exchange pipe and the power of a circulating pump is realized, and a dynamic regulation and control mechanism can automatically optimize the blowing gas flow velocity and the water vapor exchange area according to actual humidity changes, so that high-efficiency and stable dehydration effects can be realized under different working conditions.

Description

Technical Field

[0001] This invention relates to the field of online total sulfur analysis technology, specifically to a trace water vapor removal device and method based on membrane permeation technology. Background Technology

[0002] The online ultraviolet fluorescence total sulfur analyzer is a high-precision instrument used for real-time monitoring of the total sulfur content in liquid or gas samples. Based on the principle of ultraviolet fluorescence, it features high sensitivity, strong anti-interference ability, and fast response speed, and is widely used in many industrial fields.

[0003] The sample is fully combusted with oxygen in a high-temperature pyrolysis furnace, where sulfur compounds are quantitatively oxidized to sulfur dioxide, and some may also generate a small amount of sulfur trioxide. The reaction gas is then dehydrated using a membrane dryer or similar device to avoid interference from moisture in subsequent fluorescence measurements. The dried sulfur dioxide gas enters the reaction chamber and is irradiated with ultraviolet light of a specific wavelength. After absorbing the ultraviolet light energy, the sulfur dioxide molecules transition to an excited state. The excited sulfur dioxide molecules are unstable and quickly return to the ground state, emitting fluorescence of a specific wavelength in the process. This fluorescence is detected and received by a high-precision photomultiplier tube, which converts the light signal into an electrical signal. This signal is then amplified by a microcurrent amplifier and processed by a computer. Since the fluorescence intensity is proportional to the amount of sulfur dioxide generated, and the amount of sulfur dioxide is proportional to the total sulfur content in the sample, the total sulfur content in the sample can be calculated by measuring the fluorescence intensity.

[0004] The dehydration treatment of the reaction gas during the process is quite sensitive to operating conditions. The membrane permeation efficiency is highly dependent on temperature. When the temperature decreases, the membrane's permeability and selectivity will decrease, which may lead to incomplete dehydration. On the other hand, if the temperature is too high, it may damage the membrane material, causing changes in the humidity value of the subsequent reaction gas. Without corresponding water vapor treatment, subsequent detection may be interfered with. Similarly, in the treatment of reaction gas and purge gas, even with a pre-filter, extremely fine particles may still gradually clog the membrane pores, reduce the effective surface area, and reduce the dehydration efficiency.

[0005] Therefore, we propose a micro-water vapor removal device and method based on membrane permeation technology. Summary of the Invention

[0006] The purpose of this invention is to provide a device and method for removing trace amounts of water vapor based on membrane permeation technology, thereby solving the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a trace water vapor removal device based on membrane permeation technology, comprising a membrane drying assembly, wherein the membrane drying assembly comprises a central exchange chamber, a top cover, and a bottom cover that are constructed in an integral shell shape, and the top cover is fixed to the center of the central exchange chamber by bolts, and the bottom cover is fixed to the bottom of the central exchange chamber.

[0008] The central exchange chamber and the top cover are jointly provided with an air intake channel. The inlet of the air intake channel is located on the central exchange chamber, and the outlet is located inside the top cover. A purging channel is also provided at the bottom of the air intake channel and located on the central exchange chamber.

[0009] The central exchange chamber is connected and fixed with a fixed air exchange pipe on its upper and lower sides, and a movable air exchange pipe is movably connected inside the fixed air exchange pipe. The two sides of the movable air exchange pipe extend into the corresponding top cover and bottom cover, and are movably connected to the top cover through a sleeve bearing. Selective permeation membrane tubes are uniformly connected and arranged inside the central exchange chamber and outside the fixed air exchange pipe. The selective permeation membrane tubes are spirally and alternately distributed from the inside to the outside, and their two ends are connected to the top cover and bottom cover, respectively. An air outlet channel is fixedly connected to the bottom of the bottom cover.

[0010] Furthermore, a filling filter layer is fixed on the inner wall of the top cover and around the movable ventilation pipe. This filling filter layer is composed of a sintered metal filter screen and a coalescing filter element.

[0011] Furthermore, the movable ventilation pipe inside the top cover is connected to the ventilation pipe inside the purging channel, and a scraper is fitted on the outer wall of the movable ventilation pipe and located on top of the filling filter layer.

[0012] Furthermore, the inner wall of the movable ventilation pipe is uniformly provided with two openings, and the outer wall of the fixed ventilation pipe is uniformly provided with one opening, with the one opening and the two openings corresponding to each other. A valve sleeve is fixedly connected to the inner wall of the movable ventilation pipe at the bottom of the two openings.

[0013] Furthermore, a micro-controlled motor is provided on the top of the bottom cover, and the rotation of the movable ventilation pipe extending into the bottom cover is controlled by gear meshing. A dehumidifying cylinder is fixed on the locking ring on the outside of the central exchange chamber, and a humidity sensor is installed on the bottom cover.

[0014] Furthermore, the bottom vent pipe of the movable ventilation pipe passes through the circulation channel provided on the bottom cover and communicates with the dehumidification cylinder. The dehumidification cylinder is equipped with a circulation pump. A dehumidification plate is provided in the chamber of the dehumidification cylinder located on the side of the circulation pump outlet. A composite absorption layer is evenly provided on the dehumidification plate, and a heating component is provided on the other side of the chamber.

[0015] Furthermore, the composite absorption layer is composed of a silica gel layer and a molecular sieve layer, and is located at one end of the vent pipe and connected to the inlet chamber of the circulating pump. The outlet chamber is also connected to and fixed with an argon gas delivery pipe.

[0016] The method for removing trace amounts of water vapor based on membrane permeation technology includes the following steps:

[0017] Intelligent selective opening adjustment works in conjunction with drying gas for efficient dehydration. The reaction gas produced after being processed by the combustion furnace is discharged into the top cover through the air inlet channel, and then intercepted by the filter layer and enters each selective permeation membrane tube. During this process, the drying gas enters the front pipe of the circulation pump through the pipeline, and is then transported and discharged into the movable air exchange pipe. The wettest and hottest reaction gas enters from one end of the dryer, and the purge gas that has absorbed a small amount of moisture is flowing towards it. The driest reaction gas, which is ready to enter the fluorescence cell, is at the outlet end, and the driest purge gas that has just come out of the gas cylinder is flowing towards it.

[0018] Water molecules discharged from the selective osmosis membrane tube are discharged into the vent pipe through the drying gas and finally enter the dehumidification cylinder;

[0019] The humidity value of the reaction gas collected by the humidity sensor on the bottom cover is fed back to the external controller. Based on the collected humidity value, the micro motor and the power of the circulation pump are actively controlled. The rotation of the movable ventilation pipe realizes the adjustment of the overlapping channel area of ​​the second and first ports. Secondly, the flow rate of the drying gas is adjusted accordingly until the humidity of the reaction gas collected by the humidity sensor reaches the set value. At this time, the air outlet channel at the bottom of the bottom cover is opened and connected to the fluorescence cell.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. In this invention, the humidity of the reaction gas is monitored in real time by a humidity sensor, and the data is fed back to an external controller to realize intelligent linkage adjustment of the opening size of the active ventilation pipe and the power of the circulation pump. This dynamic control mechanism can automatically optimize the purge gas flow rate and water-air exchange area according to the actual humidity changes, ensuring that efficient and stable dehydration effect can be achieved under different working conditions. It is especially suitable for the treatment of high temperature and high humidity reaction gas, avoiding the problems of incomplete dehydration or membrane material damage caused by temperature fluctuations or membrane pore blockage in traditional membrane permeation technology, and significantly improving the dehydration accuracy and system reliability.

[0022] 2. In this invention, a scraper structure and a rotatable dehumidifying disc are provided. Together with the filling filter layer and composite absorption layer, they enable automatic cleaning of the filter layer and regeneration of the purge air. The rotation of the movable ventilation pipe is not only used to adjust the air vent, but also to drive the scraper to remove oil and particulate matter from the surface of the filter layer, delaying membrane pore blockage. At the same time, the dehumidifying disc, through rotation and cooperation with the heating component, enables the adsorbent to be regenerated alternately, keeping the purge air dry, significantly reducing purge air consumption, extending the service life of the device, reducing maintenance frequency, and possessing good economic and environmental benefits. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the trace water vapor removal device of the membrane permeation technology of the present invention;

[0024] Figure 2 This is a rear view schematic diagram of the micro-water vapor removal device of the membrane permeation technology of the present invention;

[0025] Figure 3 This is a schematic diagram of the selective permeation membrane tube installation structure within the membrane drying assembly of the present invention;

[0026] Figure 4 This is a schematic cross-sectional view of the trace water vapor removal device of the membrane permeation technology of the present invention.

[0027] Figure 5 This is a schematic diagram showing the alternating openings of the fixed and movable ventilation pipes of the present invention.

[0028] Figure 6 This is a schematic diagram of the structure of the present invention based on the circulation of purge gas inside the dehumidifier cylinder.

[0029] In the diagram: 1. Membrane drying assembly; 101. Central exchange chamber; 102. Top cover; 103. Bottom cover; 104. Purge channel; 105. Air inlet channel; 2. Filled filter layer; 3. Vent pipe; 4. Selective permeation membrane tube; 5. Fixed vent pipe; 6. Movable vent pipe; 7. Outlet 1; 8. Outlet 2; 9. Scraper; 10. Air outlet channel; 11. Circulation channel; 12. Dehumidifier cylinder; 13. Circulation pump; 14. Dehumidifier disc; 15. Composite absorption layer; 16. Heating assembly; 17. Humidity sensor. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figure 1-6 The present invention provides a technical solution:

[0032] Example 1: Improvements and adjustments were made to address the inherent defects and limitations of membrane permeation dehydration technology, such as... Figure 1 As shown, the main body of the trace moisture removal device is a membrane drying assembly 1, which is composed of a central exchange chamber 101, a top cover 102 and a bottom cover 103. The purge channel 104 and the air inlet channel 105 on the central exchange chamber 101 are connected to the top cover 102. The upper dehumidification cylinder 12 is provided on the side of the top cover 102. The bottom of the dehumidification cylinder 12 is connected to the circulation channel 11 on the bottom cover 103. The outer argon tank is connected to the dehumidification cylinder 12 through a pipe.

[0033] Argon is used as the purge gas, which comes into countercurrent contact with the reaction gas generated by the combustion furnace. The wettest and hottest reaction gas enters from one end of the dryer, and the purge gas that is about to be discharged and has absorbed a small amount of moisture flows in the opposite direction. The driest reaction gas, which is ready to enter the fluorescence cell, is at the outlet end, and the driest purge gas that has just come out of the gas cylinder, which is the purge gas that has just been discharged from the circulation channel 11, flows in the opposite direction. This method can maintain the maximum average partial pressure difference in all sections of the entire membrane fiber, with the highest efficiency, and can achieve the best drying effect with the least amount of purge gas.

[0034] The reaction gas enters through the inlet channel 105, such as Figure 4 As shown, the gas passes through the filter layer 2 inside the top cover 102 and is finally discharged into the selective permeation membrane tube 4. Considering that the initial temperature of the reaction gas is high, and the gas has just come out of the cracking furnace with a temperature of over 1000°C, although it has been cooled by a pipeline, the temperature is usually still 150°C-250°C when it enters the membrane dryer.

[0035] The membrane material is usually a perfluorosulfonic acid or similar composite membrane, which has good chemical stability and high temperature resistance. The reaction gas discharged into the selective permeation membrane tube 4 has water molecules in it that diffuse from the sample side through the membrane to the purge side due to the concentration difference and are carried away and discharged, thereby achieving continuous and efficient dehydration. The remaining detection gas is discharged into the bottom cover 103.

[0036] Depend on Figure 2 It can be understood that a humidity sensor 17 is installed on the bottom cover 103. The humidity sensor 17 is used to monitor the humidity value of the reaction gas before it enters the fluorescence detection cell. The humidity value can also provide timely feedback on the overall dehydration status of the equipment. It works in conjunction with the fixed air exchange pipe 5 and the movable air exchange pipe 6 installed on the central exchange chamber 101 to flexibly respond to the floating and changing reaction gas.

[0037] like Figure 4 and Figure 5 It can be understood that the purge air passage installed in the central exchange chamber 101 is a movable air exchange pipe 6. This pipe runs through the central exchange chamber 101 and extends to the top cover 102 and the bottom cover 103. The micro motor is installed on the side of the bottom cover 103 and drives the movable air exchange pipe 6 to rotate through gear meshing.

[0038] Furthermore, a fixed ventilation pipe 5 is installed inside the central ventilation chamber 101 located outside the movable ventilation pipe 6. Both pipes have openings in their walls; the movable ventilation pipe 6 has an opening 8, and the fixed ventilation pipe 5 has an opening 7. Opening 8 and opening 7 together form a water vapor inlet. Figure 5As shown, by changing the angle of the movable ventilation pipe 6, the area of ​​the overlapping holes of the second opening 8 and the first opening 7 can be adjusted to cope with different humidity levels of the reaction gas. Specifically, when the humidity is high, the overall size of the overlapping holes is increased to improve the water-gas exchange rate. At the same time, the flow rate of the purge gas in the movable ventilation pipe 6 is accelerated to accelerate the discharge of water molecules.

[0039] Specifically, the bottom cover 103 is the monitoring end, the humidity sensor 17 monitors the reaction gas after dehumidification and provides timely feedback on the collected humidity value. The external controller sets a minimum reaction humidity threshold and compares the real-time collected humidity value with the humidity threshold. Only when the humidity value is less than the humidity threshold can the gas be released from the outlet channel 10. Otherwise, the active control of the movable ventilation pipe 6 to rotate and adjust the opening size is activated, while the power of the circulation pump 13 located in the dehumidification cylinder 12 is increased to accelerate the flow rate of the entire purge gas in the movable ventilation pipe 6.

[0040] A flap sleeve is installed on the inner wall of the movable ventilation pipe 6 and is located at the bottom of the hole. By reducing the opening of the flap sleeve, the purge airflow rate of the hole is accelerated, thereby improving the overall water vapor extraction effect.

[0041] Through the feedback mechanism, predictive adjustment, maintenance, and fault diagnosis can be achieved. By monitoring the trend of outlet humidity changes, if the humidity reading starts to rise slowly but continues to rise, it indicates that the membrane dryer needs to be actively adjusted. If the adjustment still has no effect on the humidity value, it strongly indicates that the membrane dryer may be aging, blocked, or damaged and needs to be maintained. After replacing the membrane tube or purge air filter, the success of the maintenance can be verified by observing whether the humidity reading returns to the low baseline level.

[0042] Example 2: The movable ventilation pipe 6 and the fixed ventilation pipe 5 are adjusted in conjunction with the opening. In addition to dealing with humidity changes during operation, they can also perform active cleaning. Considering the influence of impurities in the reaction gas, some reaction gas containing oil and particulate matter enters the drying gas. The extremely fine particulate matter may still gradually block the membrane pores, reduce the effective surface area, and reduce the dehydration efficiency.

[0043] Therefore, such as Figure 4 As shown, a filter layer 2 is installed on the entire top cover 102, and a scraper 9 is fixed on the movable ventilation pipe 6. When the micro-moisture removal device is not working, the movable ventilation pipe 6 rotates to drive the scraper 9 to complete the scraping of oil stains on the top of the filter layer 2, thereby improving the overall filtration efficiency.

[0044] Similarly, a dehumidification disc 14 is installed inside the dehumidification cylinder 12. High-humidity purge air is discharged into the dehumidification cylinder 12 via the vent pipe 3 for treatment. Multiple sets of composite absorption layers 15 are installed on the dehumidification disc 14. Figure 6As shown, the composite absorption layer 15 is composed of a silica gel layer and a molecular sieve layer. The dehumidification disc 14 rotates to allow multiple sets of composite absorption layers 15 to be used alternately.

[0045] As the purge gas enters the dehumidification cylinder 12, the purge gas carrying water vapor first contacts the circulation pump 13, and then is discharged onto the composite absorption layer 15 to complete the absorption of water vapor in the purge gas. Then, through the rotation of the dehumidification disc 14, the purge gas carrying the saturated composite absorption layer 15 is moved to the top of the heating component 16. Part of the wheel is processing the wet and dirty gas, while the other part is purged by the reverse hot air in the heating zone to achieve desorption and regeneration, maintaining a certain dynamic balance. As for the replenishment of the purge gas, the purge gas after dehumidification is mixed with the new gas discharged from the tank and discharged back into the circulation channel 11 to reduce the overall purge gas loss.

[0046] For total sulfur analyzers with high precision requirements, trace amounts of volatile organic compounds, aromatic hydrocarbons, acidic gases, or sulfur-containing compounds in the sample gas may permeate to the dry gas side. In this case, using a purge gas circulation system can easily lead to the risk of contaminant accumulation. These gases continuously accumulate in the closed loop, and the concentration becomes increasingly high. Extremely high concentrations of contaminants can permeate back through the membrane, recontaminating the already clean and dry sample gas flow. This can cause the analyzer background value to rise sharply, the reading to drift significantly, and unacceptable detection errors to occur. Therefore, the entire circulation purging mechanism needs to be shut down, that is, the inlet of the circulation pump 13 needs to be connected to an external tank, and the returned purge gas should no longer be discharged into the dehumidification cylinder 12 to avoid errors.

[0047] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A trace water vapor removal device based on membrane permeation technology, comprising a membrane drying assembly (1), characterized in that, The film drying assembly (1) comprises a middle-through exchange cavity (101) which constructs an overall shell form, a top cover (102) and a bottom cover (103), and is centered on the middle-through exchange cavity (101), the top of which is fixed with the top cover (102) through bolts, and the bottom of which is fixed with the bottom cover (103); The middle-through exchange cavity (101) is provided with an air inlet channel (105) in combination with the top cover (102), the inlet of the air inlet channel (105) is arranged on the middle-through exchange cavity (101), and the outlet is arranged in the top cover (102), and the bottom of the air inlet channel (105) and the middle-through exchange cavity (101) are further provided with a purge channel (104); The middle-through exchange cavity (101) is fixed with a fixed air pipe (5) which is communicated with the upper and lower sides, and the fixed air pipe (5) is movably connected with a movable air pipe (6) arranged in the fixed air pipe (5), the movable air pipe (6) extends to the top cover (102) and the bottom cover (103) on both sides, and is movably connected with the top cover (102) through a bearing, the middle-through exchange cavity (101) is uniformly and selectively provided with a selective permeation membrane tube (4) outside the fixed air pipe (5), the selective permeation membrane tube (4) is spirally and alternately arranged from inside to outside, and the two ends are communicated with the top cover (102) and the bottom cover (103), and the bottom of the bottom cover (103) is fixedly connected with an air outlet channel (10); The inner wall of the movable air pipe (6) is uniformly provided with a second opening (8), the outer wall of the fixed air pipe (5) is uniformly provided with a first opening (7), and the first opening (7) and the second opening (8) are arranged correspondingly, and the inner wall of the movable air pipe (6) and the bottom of the second opening (8) are fixedly connected with a petal sleeve; The top of the bottom cover (103) is provided with a micro-control motor, and the rotation of the movable air pipe (6) extending into the bottom cover (103) is controlled through gear engagement, a dehumidification cylinder (12) is fixed on the locking ring outside the middle-through exchange cavity (101), and a humidity sensor (17) is installed on the bottom cover (103); The bottom pipe of the movable air pipe (6) penetrates through the bottom cover (103) to arrange a circulation channel (11) and is communicated with the dehumidification cylinder (12), the dehumidification cylinder (12) is provided with a circulating pump (13), the dehumidification cylinder (12) is provided with a dehumidification disc (14) in the chamber on the outlet side of the circulating pump (13), the dehumidification disc (14) is uniformly provided with a composite absorption layer (15), and the other side of the chamber is provided with a heating assembly (16); The movable air pipe (6) arranged in the top cover (102) is communicated with the air pipe (3) arranged in the purge channel (104).

2. The membrane permeation technology based trace water vapor removal device according to claim 1, wherein, The inner wall of the top cover (102) and the periphery of the movable air pipe (6) are fixed with a filling filter layer (2) which is composed of a sintered metal filter screen and a coalescing filter element.

3. The membrane permeation technology based trace water vapor removal device of claim 2, wherein, The outer wall of the movable air pipe (6) and the top of the filling filter layer (2) are provided with a scraping strip (9).

4. The membrane permeation technology based trace water vapor removal device of claim 3, wherein, The composite absorption layer (15) is composed of a silica gel layer and a molecular sieve layer, one end of the air pipe (3) is communicated with the chamber on the inlet side of the circulating pump (13), and the chamber on the outlet side is further communicated with an argon gas delivery pipe.

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