A high pressure gas re-circulating flow dry pipe with bed and seal monitoring and method

Abstract

The application discloses a high-pressure gas return flow drying pipe with bed layer and sealing monitoring and a method, relates to the technical field of adsorption drying equipment, and comprises an outer pressure-bearing pipe, a guide cage and an inner flow guide pipe which are coaxially arranged from outside to inside; the gas inlet of the inner flow guide pipe extends from the top of the outer pressure-bearing pipe, and the gas outlet extends into the guide cage; the annular cavity between the outer pressure-bearing pipe and the guide cage is a dry gas collecting cavity; the annular cavity between the guide cage and the inner flow guide pipe is filled with adsorbent; the upper part of the guide cage and the inner flow guide pipe is connected in a sliding sealing mode through an annular compression sieve plate, and the lower part is fixedly connected through a fixed sieve plate; the annular compression sieve plate is provided with a magnetic mark; a magnetic field sensor is arranged outside the outer pressure-bearing pipe to monitor the position of the adsorbent bed layer; the outer pressure-bearing pipe and the inner flow guide pipe are connected through flanges and are sealed through two sealing rings; the annular cavity between the two sealing rings is a monitoring cavity, and the sealing state is monitored; the application is suitable for high-pressure gas drying, can improve the drying efficiency, and has the functions of bed layer position monitoring and sealing monitoring.

Description

Technical Field

[0001] This invention relates to the field of adsorption drying equipment technology, specifically to a high-pressure gas backflow drying tube and its bed and sealing operation method. Background Technology

[0002] High-pressure gases have a wide range of applications, but their components often contain moisture, which can lead to various risks such as pipeline corrosion and blockage, system failure, and catalyst deactivation. Therefore, they must be dried and purified. Traditional solutions use independent adsorption and drying devices, which are large, occupy a large area, have complex piping, and suffer from high pressure loss, making them unsuitable for space-constrained applications.

[0003] To address the aforementioned issues, existing technologies propose integrated cylindrical drying tubes within the pipeline, offering a compact structure and saving installation space. However, existing cylindrical drying tubes suffer from the following drawbacks: 1. Due to size constraints, the adsorbent bed thickness and gas flow channel in existing drying tubes are relatively short, resulting in insufficient contact time between the gas and adsorbent, inadequate drying, and substandard outlet dew point. Increasing the pipe diameter or length contradicts the goals of compact and miniaturized design. 2. Bed settling monitoring is impossible. After long-term operation, the particulate adsorbent inside the drying tube will shrink in volume, reducing the bed height and creating voids, leading to humid gas bypass and reduced drying efficiency. 3. For ease of maintenance, existing drying tubes often use flanged split connections. Under high pressure, pressure fluctuations, and vibration environments, the sealing rings are prone to failure, but existing technologies lack monitoring of the sealing ring's tightness, making it impossible to detect leaks in a timely manner. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a high-pressure gas backflow drying tube and method with bed and seal monitoring, which is adapted to high-pressure gas drying, can improve drying efficiency, and also has the functions of monitoring the position of the adsorbent bed and the seal of the sealing ring.

[0005] The technical solution of the present invention is as follows: In a first aspect of the invention, a high-pressure gas backflow drying tube with bed and sealing monitoring is provided, comprising an outer pressure-bearing tube, a guide cage, and an inner guide tube arranged coaxially from the outside to the inside; the inlet of the inner guide tube extends from the top of the outer pressure-bearing tube, and the outlet extends into the guide cage; the annular cavity between the outer pressure-bearing tube and the guide cage serves as a dry gas collection cavity; the annular cavity between the guide cage and the inner guide tube is filled with an adsorbent; the gas to be dried passes through the inner guide tube, the adsorbent, and the dry gas collection cavity in sequence, and is discharged from the bottom of the outer pressure-bearing tube. The upper part of the guide cage and the inner guide pipe are slidably sealed together by an annular pressing screen plate, and the lower part is fixedly connected by a fixed screen plate. The annular pressing screen plate is provided with magnetic marks, and a magnetic field sensor is provided on the outside of the outer pressure pipe to monitor the position of the adsorbent bed. The outer pressure pipe and the inner guide pipe are connected by a flange and sealed by two sealing rings. The annular cavity between the two sealing rings serves as a monitoring cavity to monitor the sealing status.

[0006] In some embodiments of the present invention, the top of the external pressure-bearing pipe is provided with an upper flange and the bottom is provided with a lower flange. The upper part of the inner guide pipe is provided with an annular insert plate. The upper flange and the annular insert plate are connected by bolts, and the mating surface of the upper flange and the annular insert plate is sealed by a first sealing ring and a second sealing ring. The first sealing ring is located inside the second sealing ring, and the two sealing rings are separated by a set distance.

[0007] In some embodiments of the present invention, the annular pressing screen plate and the annular insert plate are connected by an elastic pressing member, which is one of a wave spring, a disc spring group, a spiral compression spring or an elastic bellows, and its effective compression stroke is not less than the allowable settling stroke of the adsorbent bed.

[0008] In some embodiments of the present invention, the inner wall surface of the annular pressing screen plate is dynamically sealed to the outer wall surface of the inner guide tube through an inner sliding seal, and the outer ring surface of the annular pressing screen plate is dynamically sealed to the guide cage through an outer sliding seal.

[0009] In some embodiments of the present invention, the magnetic field sensor includes a first magnetic field sensor and a second magnetic field sensor. The two magnetic field sensors are mounted on the outside of the outer pressure-bearing pipe by a sensor bracket. The axial distance between the two magnetic field sensors covers the entire allowable stroke of the annular pressing screen plate. The outer wall of the outer pressure-bearing pipe is also provided with a temperature sensor to perform temperature compensation on the magnetic field detection signal.

[0010] In some embodiments of the present invention, the bottom wall of the guide cage is arranged opposite to the lower end air outlet of the inner guide pipe, and the space between the bottom of the guide cage and the lower end air outlet of the inner guide pipe serves as a guide cavity.

[0011] In some embodiments of the present invention, the monitoring chamber is connected to a monitoring tube via a monitoring connector. A first monitoring point is provided on the monitoring tube. The first monitoring point is connected to the low-pressure end of the differential pressure sensor. The monitoring tube is connected to the common end of a switching valve. The first end of the switching valve is connected to the outlet connector via a dry gas reference branch. The second end is connected to the test gas connector via a pipeline. A safety check valve and a calibration throttling device are provided on the dry gas reference branch. A second monitoring point is provided on the pipeline between the calibration throttling device and the outlet connector. The second monitoring point is connected to the high-pressure end of the differential pressure sensor.

[0012] In a second aspect of the invention, a method for operating a high-pressure gas backflow drying tube with bed and seal monitoring is provided, comprising: The gas to be dried enters through the inlet of the inner guide tube and exits through the outlet. It then passes through the fixed sieve plate into the adsorbent bed, where it comes into contact with the adsorbent for drying. The dried gas then passes through the annular pressing sieve plate and enters the dry gas collection chamber, finally exiting at the bottom of the outer pressure pipe. During the operation of the drying tube, the pressure of the monitoring chamber is monitored in real time to determine whether the sealing ring has failed; at the same time, the position of the magnetic marker is monitored in real time to monitor the position of the adsorbent bed and determine the bed settling state.

[0013] In some embodiments of the present invention, determining whether the sealing ring has failed specifically includes: the monitoring tube is connected to the dry gas reference branch through a switching valve, and high-pressure gas with the same pressure as the dry gas collection chamber is depressurized by a calibrated throttling device and then input into the monitoring chamber; the differential pressure sensor collects the pressure difference between the second monitoring point and the first monitoring point in real time; when the pressure difference value is stable, neither of the two sealing rings has failed; when the pressure difference value continues to decrease, it is determined that the first sealing ring has leaked; when the pressure difference value continues to increase, it is determined that the second sealing ring has leaked. Determining the bed settlement status specifically includes: collecting magnetic field data of magnetic markers through a first magnetic field sensor and a second magnetic field sensor, converting the magnetic field data into position feature data, and determining the bed settlement status based on the position feature data.

[0014] In some embodiments of the present invention, during the shutdown period, the monitoring tube is connected to the test gas connector through the switching valve to deliver test gas into the monitoring chamber, and then the monitoring tube is connected to the dry gas reference branch through the switching valve. The overall sealing performance of the two sealing rings is determined based on the change in the value of the differential pressure sensor.

[0015] One or more technical solutions of the present invention have the following beneficial effects: (1) The present invention adopts a zigzag flow structure in which an outer pressure-bearing pipe, a guide cage, and an inner guide pipe are coaxially arranged from the outside to the inside. The gas to be dried enters from the top of the inner guide pipe and flows downward, then flows upward through the annular adsorption chamber after being zigzag from the bottom of the guide cage. The dried gas enters the dry gas collection chamber between the outer pressure-bearing pipe and the guide cage, and is finally discharged from the bottom. This structure integrates air intake, drying, collection, and exhaust into a single tubular structure, eliminating the need for complex external pipeline connections and significantly reducing the equipment volume and floor space. At the same time, the gas completes the entire process of "downward-zigzag-upward" within a limited axial space, effectively extending the contact time with the adsorbent and solving the problem of short flow channels and insufficient drying caused by the size constraints of existing straight cylindrical drying pipes.

[0016] (2) The present invention sets magnetic marks on the annular pressing screen plate and sets a magnetic field sensor on the outside of the outer pressure-bearing pipe to monitor the position of the adsorbent bed. At the same time, the annular pressing screen plate is loaded by the elastic pressing component and can slide axially with the adsorbent settling, always keeping the bed compacted; together with the inner and outer sliding seals, the inner guide pipe and the guide cage form a dynamic seal, which completely blocks the possibility of gas bypassing from the gap at the edge of the screen plate, ensuring that the gas must penetrate the adsorbent bed and maintain a long-term stable drying efficiency.

[0017] (3) In this invention, a double-sealing structure consisting of a first sealing ring and a second sealing ring is adopted at the flange connection between the outer pressure-bearing pipe and the inner guide pipe. The monitoring cavity formed between the two rings is connected to the dry gas reference branch through a monitoring pipe. The clean gas in the dry gas reference branch is directly taken from the high-pressure gas in the dry gas collection cavity generated by the equipment itself (after being depressurized by the calibrated throttling device), without the need to add an external reference gas source, which simplifies the system structure and avoids secondary pollution caused by moisture intrusion due to atmospheric reference. During monitoring, the differential pressure sensor collects the difference between the monitoring cavity pressure and the reference pressure. Based on the trend of the pressure difference rise and fall, the leakage direction of the two sealing rings can be distinguished online and intuitively. The judgment method is simple and reliable, without the need for complex correlation coefficient calculations.

[0018] (4) This invention, through a switching valve and a test gas connector, allows the input of a test gas pulse into the monitoring chamber during downtime. Subsequently, it switches to the dry gas reference branch and records the differential pressure decay curve, thereby evaluating the overall sealing integrity of the two sealing rings. This self-testing pathway can be completed using the equipment's own valves and sensors, without interfering with online monitoring during normal operation, further improving the convenience of equipment maintenance and operational reliability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the internal structure of the high-pressure gas reversing flow drying tube and a schematic diagram of the gas reversing flow direction of the present invention; Figure 2 This is an enlarged schematic diagram showing the connection relationship between the annular pressing screen plate, guide cage, magnetic marker and external magnetic field sensor of the present invention; Figure 3 This is a schematic diagram of the pipeline and wiring connections used for sealing monitoring in this invention.

[0020] In the diagram: 1. Inlet of the inner guide pipe; 2. Outlet of the outer pressure-bearing pipe; 3. Monitoring module; 4. Upper flange; 5. Outer pressure-bearing pipe; 6. Annular adsorption chamber; 7. Inner guide pipe; 8. Guide chamber; 9. Lower flange; 10. Double sealing assembly; 11. Annular insert plate; 12. Flange mating sealing surface; 13. First sealing ring; 14. Second sealing ring; 15. Monitoring chamber; 16. Monitoring connector; 17. Fixed sieve plate; 18. Annular pressing sieve plate; 19. Inner sliding seal; 20. Outer sliding seal; 21. Elastic pressing element; 22. Magnetic... Markings; 23. First magnetic field sensor; 24. Second magnetic field sensor; 25. Switching valve; 26. Differential pressure sensor; 27. Calibration throttling device; 28. Dry gas reference branch; 29. ​​Test gas connector; 30. Monitoring controller; 31. Temperature sensor; 32. Pre-filter layer; 33. Deep drying layer; 34. Dry gas collection chamber; 35. Guide cage; 36. Safety check valve; 37. Alarm / interlock output terminal; 38. Sensor bracket; 39. First monitoring point; 40. Second monitoring point; 41. Monitoring tube; 42. Gas outlet connector. Detailed Implementation

[0021] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is intended to include the plural form as well. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] Example 1 In a typical embodiment of the present invention, a high-pressure gas backflow drying tube with bed and seal monitoring is disclosed, such as... Figure 1 and Figure 2As shown, it includes an outer pressure-bearing pipe 5, a guide cage 35, and an inner guide pipe 7 arranged coaxially from the outside to the inside; the outer pressure-bearing pipe 5 serves as the external pressure-bearing structure of the entire drying pipe, bearing the pressure load of the internal high-pressure gas; the guide cage 35 is located between the outer pressure-bearing pipe 5 and the inner guide pipe 7, used to constrain the outer boundary of the adsorbent bed; the inner guide pipe 7 is located in the innermost layer, serving as the inlet channel for the gas to be dried; the three-layer pipe structure is arranged coaxially to form two annular cavities.

[0024] Specifically, the air inlet of the inner guide pipe 7 extends from the top of the outer pressure pipe 5, facilitating connection with the external air supply pipeline, and its outlet extends into the guide cage 35; the annular cavity between the outer pressure pipe 5 and the guide cage 35 serves as the dry gas collection cavity 34, used to collect the gas dried by the adsorbent; the annular cavity between the guide cage 35 and the inner guide pipe 7 serves as the annular adsorption cavity 6, filled with adsorbent, and the annular adsorption cavity 6 serves as the core working area for adsorption drying; after the gas to be dried passes through the inner guide pipe 7, the adsorbent, and the dry gas collection cavity 34 in sequence, it is discharged from the bottom of the outer pressure pipe 5, forming a reversible flow path, extending the contact time between the gas and the adsorbent, and improving the drying efficiency.

[0025] Furthermore, the upper part of the guide cage 35 and the inner guide pipe 7 are slidably sealed and connected by an annular pressing screen plate 18, and the lower part is fixedly connected by a fixed screen plate 17. The annular pressing screen plate 18 can slide freely along the axial direction to apply a pressing force to the adsorbent bed. The fixed screen plate 17 is used to support the bottom of the adsorbent bed and prevent adsorbent particles from leaking. A magnetic mark 22 is provided on the annular pressing screen plate 18, and a magnetic field sensor is provided on the outside of the outer pressure-bearing pipe 5. The magnetic field sensor indirectly reflects the displacement of the annular pressing screen plate 18 by detecting the axial position change of the magnetic mark 22, thereby realizing real-time monitoring of the position of the adsorbent bed. When the height of the bed changes due to adsorbent wear, pulverization or sedimentation, the bed status can be known in time.

[0026] Furthermore, the outer pressure-bearing pipe 5 and the inner guide pipe 7 are connected by a flange and sealed by two sealing rings to form a double sealing structure. The annular cavity between the two sealing rings serves as a monitoring cavity 15. When the first sealing ring near the high-pressure side leaks, the leaking gas enters the monitoring cavity 15. The sealing status can be judged in a timely manner by the pressure change of the monitoring cavity 15, thereby realizing dynamic monitoring of the sealing performance and preventing high-pressure gas leakage from causing safety accidents.

[0027] In this embodiment, the top of the external pressure-bearing pipe 5 is provided with an upper flange 4 and the bottom with a lower flange 9. The upper part of the inner guide pipe 7 is provided with an annular insert plate 11. The upper flange 4 and the annular insert plate 11 are connected by bolts. The lower flange 9 is used to connect with the external pipeline. The mating surface of the upper flange 4 and the annular insert plate 11 serves as the flange mating sealing surface 12. The sealing is achieved by a double sealing assembly 10. The double sealing assembly 10 includes a first sealing ring 13 and a second sealing ring 14. The first sealing ring 13 is located inside the second sealing ring 14 (i.e., the first sealing ring 13 is in contact with the high-pressure gas inside the drying pipe, and the second sealing ring 14 is in contact with the external ambient gas), forming an inner and outer double-ring sealing structure. The two sealing rings are separated by a set distance, which constitutes the axial width of the monitoring cavity 15, providing effective space for monitoring the sealing status.

[0028] Furthermore, the annular pressing screen plate 18 and the annular insert plate 11 are connected by an elastic pressing member 21. The elastic pressing member 21 is one of a wave spring, a disc spring group, a spiral compression spring, or an elastic bellows. Its effective compression stroke is not less than the allowable settling stroke of the adsorbent bed. When the volume of the adsorbent bed shrinks due to wear or compaction, the elastic pressing member 21 can automatically extend to compensate for the change in bed height, maintaining the annular pressing screen plate 18 in close contact with the adsorbent bed, thereby ensuring the uniformity of the filling density between adsorbent particles and the airflow distribution.

[0029] To improve the drying effect of the adsorbent, a pre-filter layer 32 and a deep drying layer 33 are sequentially arranged along the gas flow direction in the annular adsorption chamber 6. The adsorbent can be molecular sieve, activated alumina, silica gel, or a combination thereof. The specific layering and packing density are determined according to the target dew point, flow rate, and regeneration method. The sieve openings of the fixed sieve plate 17 and the annular pressing sieve plate 18 are smaller than the equivalent particle size of the smallest adsorbent particle, and a sintered metal mesh is provided on the side facing the adsorbent to limit particle and dust migration. Figure 1 The intermediate pre-filtration layer 32 is represented by sparse hollow circles, and the deep drying layer 33 is represented by dense solid dots. The solid line between the two layers indicates the boundary. The two filling patterns are only used to distinguish the layers and do not represent the actual particle ratio.

[0030] Furthermore, annular spring seats can be provided on the upper surface of the annular pressing screen plate 18 and the lower surface of the upper flange 4 to realize the installation of the elastic pressing component 21. The outer diameter of the annular spring seat is smaller than the inner diameter of the guide cage 35. In other embodiments, multiple elastic elements arranged circumferentially can also be used to jointly constitute the elastic pressing component 21. It should be noted that the guide cage 35 is a non-magnetic cylindrical structure with an open top and a closed bottom. The top of the guide cage 35 is separated from the annular insert plate 11 on the inner guide pipe 7 by a set distance. Therefore, the space between the top of the guide cage 35 and the annular insert plate 11 on the inner guide pipe 7 serves as part of the dry gas collection cavity 34, which is connected to the annular dry gas collection cavity 34 between the guide cage 35 and the outer pressure pipe 5. The setting of the elastic pressing component 21 will not affect the connection between the two parts. An annular limiting component is provided on the upper part of the inner wall of the guide cage 35 to prevent the annular pressing screen plate 18 from falling out of the guide cage 35.

[0031] In this embodiment, the inner wall of the annular pressing screen plate 18 is dynamically sealed to the outer wall of the inner guide pipe 7 through the inner sliding seal 19, and the outer ring of the annular pressing screen plate 18 is dynamically sealed to the guide cage 35 through the outer sliding seal 20. The inner sliding seal 19 and the outer sliding seal 20 together constitute the dynamic sealing structure of the annular pressing screen plate 18 when it slides axially back and forth. This ensures that the annular pressing screen plate 18 can slide freely to adapt to changes in bed height, and also prevents undried gas from bypassing and flowing through the gap between the annular pressing screen plate 18 and the adjacent pipe wall, ensuring that the gas flows through the adsorbent bed strictly according to the designed path.

[0032] In this embodiment, the magnetic field sensor includes a first magnetic field sensor 23 and a second magnetic field sensor 24. The two magnetic field sensors are mounted on the outside of the outer pressure pipe 5 via a sensor bracket 38. The axial distance between the two magnetic field sensors covers the entire allowable stroke of the annular pressing screen plate 18. When the magnetic mark 22 moves with the annular pressing screen plate 18, the two sensors detect the magnetic field change signal as the magnetic mark 22 passes by. By comparing the signal timing and intensity difference between the two sensors, the current position of the annular pressing screen plate 18 can be accurately determined. The outer wall of the outer pressure pipe 5 is also provided with a temperature sensor 31 to perform temperature compensation on the magnetic field detection signal, eliminate the influence of temperature changes on the magnetic induction intensity, and improve the accuracy and reliability of bed position monitoring.

[0033] In this embodiment, the bottom wall of the guide cage 35 is positioned opposite to the lower end outlet of the inner guide pipe 7. The space between the bottom of the guide cage 35 and the lower end outlet of the inner guide pipe 7 serves as the guide cavity 8. After the drying gas is ejected from the outlet of the inner guide pipe 7, it is turned and evenly distributed within the guide cavity 8. Subsequently, it enters the adsorbent bed evenly through the fixed sieve plate 17, avoiding the direct impact of the airflow on the adsorbent and preventing local channeling or deflection.

[0034] like Figure 3 As shown, a monitoring module 3 is also provided. The monitoring module 3 includes a switching valve 25, a differential pressure sensor 26, a calibration throttling device 27, a dry gas reference branch 28, a test gas connector 29, a monitoring controller 30, a safety check valve 36, and an alarm / interlock output terminal 37. The monitoring controller 30 is a signal processing and status determination unit. The first magnetic field sensor 23, the second magnetic field sensor 24, and the temperature sensor 31 are installed on the outside of the outer pressure-bearing pipe 5 as signal acquisition components of the monitoring module 3 and are connected to the monitoring controller 30 by electrical signals. The magnetic marker 22 is a permanent magnet or magnetic coded ring embedded in the annular pressing screen plate 18. The magnetic marker 22 itself is not wired to the monitoring controller 30 through the pressure-bearing boundary. The components can be integrated into the same housing or installed separately and connected by pipelines and electricity to form the monitoring module 3.

[0035] Furthermore, the monitoring chamber 15 is connected to the monitoring tube 41 via the monitoring connector 16. A first monitoring point 39 is provided on the monitoring tube 41, and the first monitoring point 39 is connected to the low-pressure end of the differential pressure sensor 26. The monitoring tube 41 is connected to the common end of the switching valve 25. The first end of the switching valve 25 is connected to the dry gas reference branch 28, and the second end is connected to the test gas connector 29 via a pipeline. A safety check valve 36 and a calibration throttling device 27 are provided on the dry gas reference branch 28. A second monitoring point 40 is provided on the pipeline between the calibration throttling device 27 and the gas outlet connector 42. The second monitoring point 40 is connected to the high-pressure end of the differential pressure sensor 26. By switching different gas paths through the switching valve 25, online monitoring and shutdown monitoring can be realized. Among them, the monitoring connector 16 is a pressure tapping interface on the wall of the monitoring chamber 15, and the monitoring connector 16 is connected to the monitoring tube 41. The first monitoring point 39 is used to collect the pressure P of the monitoring chamber 15. The switching valve 25 can be a three-way valve or an equivalent valve group, used to switch between online and offline monitoring. The calibration throttling device 27 can be a precision orifice plate, capillary tube or lockable needle valve with a known flow coefficient, used to control the pressure P of the high-pressure gas. in The pressure is reduced to the calibrated pressure P1; the safety check valve 36 only allows reference dry gas to flow from the outlet connector 42 side to the monitoring node, preventing the medium in the monitoring chamber 15 from flowing back into the dry gas outlet. The outlet connector 42 is connected to the dry gas collection chamber 34 in the external pressure-bearing pipe 5 through a pipeline, so that the pressure at the second monitoring point 40 is equal to the high-pressure gas pressure P in the dry gas collection chamber 34. in It should be noted that the calibration pressure P1 is the high-pressure gas pressure P. in The value between the environmental pressure P0 and the environmental pressure.

[0036] In this embodiment, the magnetic marker 22 is embedded in the outer edge of the annular pressing screen plate 18 and moves synchronously with it. The first magnetic field sensor 23 and the second magnetic field sensor 24 are mounted on the outside of the outer pressure-bearing pipe 5 via the sensor bracket 38. The outer pressure-bearing pipe 5 is made of austenitic stainless steel or other low-permeability pressure-bearing material, at least in the area radially corresponding to the magnetic marker 22, so that the external sensors can detect the magnetic field without providing a through hole. The temperature sensor 31 is attached to the outer wall of the outer pressure-bearing pipe 5, and the monitoring controller 30 uses the temperature calibration curve to compensate for the remanence of the magnet and the change in sensor sensitivity. Further, the first magnetic field sensor 23 and the second magnetic field sensor 24 are arranged axially at intervals, and the sensitive axis directions are consistent; if the installation directions are inconsistent, they are first converted to a unified direction according to their respective calibration coefficients. The monitoring controller 30 is connected to the first magnetic field sensor 23, the second magnetic field sensor 24, the temperature sensor 31, the differential pressure sensor 26, and the switching valve 25.

[0037] In this embodiment, the outer pressure-bearing pipe 5, the upper flange 4, the lower flange 9, and the metal internal parts in contact with the medium can be selected from 316L austenitic stainless steel or other compatible materials according to the design pressure, medium, temperature, and number of cycles. The first sealing ring 13, the second sealing ring 14, and the sliding seal can be selected from pressure-resistant sealing materials such as fluororubber, polytetrafluoroethylene, and perfluoroether rubber composites according to the compatibility of the medium. The inner guide pipe 7, the fixed screen plate 17, the guide cage 35, the annular insert plate 11, the annular pressing screen plate 18, and the guide cavity 8 constitute an integral inner core assembly, which can be completely extracted from the upper flange 4. The annular adsorbent bed is maintained within the filling space enclosed by the fixed screen plate 17, the guide cage 35, and the annular pressing screen plate 18. After disconnecting the annular insert plate 11 from the upper flange 4, the inner core assembly can be completely extracted from the upper end; the outer pressure-bearing pipe 5 continues to serve as an independent main pressure-bearing boundary. This structure allows adsorbent replacement, screen cleaning, and clamping mechanism inspection to be completed without cutting the outer pressure pipe 5.

[0038] In the drying tube provided in this embodiment, high-pressure humid gas enters the inner guide tube 7 through the air inlet 1 of the inner guide tube and flows downward. It changes direction in the guide cavity 8, passes through the fixed sieve plate 17 and enters the annular adsorption cavity 6. After passing through the pre-liquid removal filter layer 32 and the deep drying layer 33 in sequence, it flows upward, passes through the annular pressing sieve plate 18 and enters the upper dry gas collection cavity 34, and is then discharged through the air outlet 2 of the outer pressure pipe. Figure 1 The arrows in the diagram illustrate the aforementioned reversal flow path.

[0039] During the operation of the drying tube, the bed position and sealing status are monitored in real time, as follows: Regarding bed position monitoring, the magnetic marker 22 moves axially along the annular pressing sieve plate 18, and the first magnetic field sensor 23 and the second magnetic field sensor 24 detect the changes in magnetic field strength generated by the magnetic marker 22 in real time. The monitoring controller 30 receives two magnetic field signals and the compensation signal from the temperature sensor 31, and converts the magnetic field strength into the absolute displacement of the annular pressing sieve plate 18 through a preset magnetic field-position mapping model. Since the annular pressing sieve plate 18 maintains close contact with the top of the adsorbent bed, this displacement directly represents the current height of the adsorbent bed. The monitoring controller 30 compares the real-time bed height with the initial filling height or the preset safety lower limit threshold. When the bed settling exceeds the allowable range, it determines that the adsorbent has been excessively pulverized or lost, triggering the alarm / interlock output terminal 37 to issue a warning signal, prompting the operator to check or replenish the adsorbent.

[0040] Regarding the monitoring of the sealing condition, it mainly relies on the second monitoring point 40 (dry gas reference line pressure P) collected by the differential pressure sensor 26. in The pressure difference ΔP (P) between the first monitoring point 39 (pressure P in monitoring chamber 15) and the first monitoring point 39 (pressure P) in The system performs online diagnostics based on the variation pattern of the pressure difference (ΔP). Switching valve 25 is in online monitoring position I, and monitoring chamber 15 is connected to the high-pressure dry gas reference branch 28 via calibration throttling element 27. If the first sealing ring 13 (inner high-pressure side seal) leaks, high-pressure process gas seeps into monitoring chamber 15, causing the pressure in monitoring chamber 15 to rise, thus reducing the pressure difference ΔP between the first monitoring point 39 and the second monitoring point 40. If the second sealing ring 14 (outer environmental side seal) leaks, gas in monitoring chamber 15 leaks to the external environment, causing the pressure in monitoring chamber 15 to drop, thus increasing the pressure difference. The monitoring controller 30 calculates and tracks the trend of this pressure difference value in real time: when the pressure difference value is stable within the calibration range, the double-sealing assembly 10 is deemed intact; when the pressure difference value continuously deviates from the normal range and exceeds the set threshold, the failed sealing ring is accurately located according to the direction of deviation, and a corresponding fault code is output through the alarm / interlock output terminal 37, achieving early detection and precise location of seal failure, ensuring safe high-pressure operation.

[0041] When monitoring the sealing status is required while the system is shut down, switching valve 25 is first switched to shutdown monitoring position II, and monitoring chamber 15 is connected to test gas connector 29 via switching valve 25. At this time, an external gas source (such as a nitrogen cylinder or compressed air source) is injected into monitoring chamber 15 through test gas connector 29 at a set pressure P. t The test gas, and P tThe pressure is greater than P0, establishing a pressure environment in monitoring chamber 15 independent of the drying tube. Then, switching valve 25 is switched to online monitoring position I, cutting off the test gas supply and placing monitoring chamber 15 in a closed, pressure-maintaining state. Monitoring controller 30 collects the differential pressure data between the first monitoring point 39 and the second monitoring point 40 from differential pressure sensor 26. If the differential pressure remains stable or the rate of change is lower than the preset leakage threshold, the overall sealing performance of the two sealing rings is considered good; if the differential pressure shows abnormally rapid decay or increase, a sealing defect is indicated. This shutdown monitoring mode can be executed before equipment maintenance, restart, or during regular maintenance to verify the integrity of the dual-sealing assembly 10, eliminate potential interference factors in online monitoring, and ensure the sealing reliability of the drying tube before it is put back into high-pressure operation. It should be noted that, due to the pressure P in the external pressure-bearing pipe 5 during shutdown, in The pressure is equal to the ambient pressure P0, therefore this monitoring process is used for overall seal integrity evaluation, not for locating leaks in a single seal.

[0042] Example 2 In a typical embodiment of the present invention, a method for operating a high-pressure gas backflow drying tube with bed and seal monitoring is provided, comprising: the gas to be dried enters from the inlet 1 of the inner guide tube, flows downward through the inner guide tube 7, exits from its outlet, passes through the fixed sieve plate 17 and enters the adsorbent bed, making full contact with the adsorbent particles, and the moisture is adsorbed by the adsorbent to achieve gas drying; the dried gas is discharged through the annular pressing sieve plate 18 and enters the dry gas collection chamber 34, and finally exits at the bottom outlet of the outer pressure pipe 5, completing the entire drying process; during the operation of the drying tube, the pressure of the monitoring chamber 15 is monitored in real time to determine whether the sealing ring has failed; at the same time, the position of the magnetic marker 22 is monitored in real time. The magnetic marker 22 moves with the movement of the annular pressing sieve plate 18. By detecting the displacement of the magnetic marker 22 through a magnetic field sensor, the position of the adsorbent bed can be monitored, the bed settling state can be determined, and a basis for replenishing or replacing the adsorbent can be provided.

[0043] Further, determining whether the sealing rings have failed involves the following steps: Monitoring pipe 41 is connected to dry gas reference branch 28 via switching valve 25. High-pressure gas with the same pressure as the dry gas manifold 34 is depressurized by calibrated throttling device 27 and then input into monitoring chamber 15. By analyzing the pressure difference value, it is determined which of the two sealing rings has leaked and the severity of the leak. Differential pressure sensor 26 collects the pressure difference data between the first monitoring point 39 and the second monitoring point 40 in real time at a set frequency and transmits the collected pressure difference signal to monitoring controller 30 for analysis and processing. When the pressure difference value remains stable, it indicates that the gas pressure in monitoring chamber 15 is in a balanced state, neither sealing ring has failed, and the sealing performance is good. When the pressure difference value continues to decrease, it is determined that the first sealing ring 13 has leaked, and external high-pressure gas continuously seeps into monitoring chamber 15. When the pressure difference value continues to increase, it is determined that the second sealing ring 14 has leaked, and the pressure in monitoring chamber 15 gradually releases to the atmospheric side. By judging the above pressure difference change trend, the specific location of the seal failure can be accurately identified, providing clear guidance for subsequent maintenance.

[0044] The specific steps for determining the bed settling state include: real-time acquisition of magnetic field strength and distribution data of magnetic marks 22 on the annular pressing screen plate 18 by the first magnetic field sensor 23 and the second magnetic field sensor 24, respectively; transmission of the acquired magnetic field data to the data processing unit; conversion of the magnetic field data into corresponding position feature data after signal conditioning and filtering; and determination of the settling state and compaction degree of the adsorbent bed based on the changing pattern of the position feature data, thereby achieving continuous and online monitoring of the bed height.

[0045] Furthermore, during shutdown, the monitoring tube 41 is connected to the test gas connector 29 via the switching valve 25, supplying test gas at a set pressure into the monitoring chamber 15 to create a stable gas pressure environment. Then, the monitoring tube 41 is connected to the dry gas reference branch 28 via the switching valve 25. Based on the changes in the differential pressure sensor 26, the overall sealing performance of the two sealing rings is assessed to determine whether it meets the requirements. This offline testing method allows for periodic inspection of the sealing rings during non-operational periods, ensuring the long-term reliable operation of the sealing structure.

[0046] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A high-pressure gas backflow drying tube with bed and seal monitoring, characterized in that, It includes an outer pressure-bearing pipe, a guide cage, and an inner guide pipe arranged coaxially from the outside to the inside; the air inlet of the inner guide pipe extends from the top of the outer pressure-bearing pipe, and the air outlet extends into the guide cage. The annular cavity between the outer pressure-bearing pipe and the guide cage serves as a dry gas collection cavity. The annular cavity between the guide cage and the inner guide pipe is filled with an adsorbent. After the dry gas passes through the inner guide pipe, the adsorbent, and the dry gas collection cavity in sequence, it is discharged from the bottom of the outer pressure-bearing pipe. The upper part of the guide cage and the inner guide pipe are slidably sealed together by an annular pressing screen plate, and the lower part is fixedly connected by a fixed screen plate. The annular pressing screen plate is provided with magnetic marks, and a magnetic field sensor is provided on the outside of the outer pressure pipe to monitor the position of the adsorbent bed. The outer pressure pipe and the inner guide pipe are connected by a flange and sealed by two sealing rings. The annular cavity between the two sealing rings serves as a monitoring cavity to monitor the sealing status.

2. The high-pressure gas backflow drying tube with bed and sealing monitoring as described in claim 1, characterized in that, The outer pressure-bearing pipe has an upper flange at the top and a lower flange at the bottom. The inner guide pipe has an annular insert plate at the top. The upper flange and the annular insert plate are connected by bolts. The mating surfaces of the upper flange and the annular insert plate are sealed by a first sealing ring and a second sealing ring. The first sealing ring is located inside the second sealing ring, and the two sealing rings are spaced a set distance apart.

3. The high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 2, characterized in that, The annular pressing screen plate and the annular insert plate are connected by an elastic pressing component. The elastic pressing component is one of a wave spring, a disc spring group, a spiral compression spring, or an elastic bellows, and its effective compression stroke is not less than the allowable settling stroke of the adsorbent bed.

4. The high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 1, characterized in that, The inner wall of the annular pressing screen plate is dynamically sealed to the outer wall of the inner guide pipe through an inner sliding seal, and the outer ring of the annular pressing screen plate is dynamically sealed to the guide cage through an outer sliding seal.

5. The high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 1, characterized in that, The magnetic field sensor includes a first magnetic field sensor and a second magnetic field sensor. The two magnetic field sensors are mounted on the outside of the outer pressure-bearing pipe through a sensor bracket. The axial distance between the two magnetic field sensors covers the entire allowable stroke of the annular pressing screen plate. The outer wall of the outer pressure-bearing pipe is also equipped with a temperature sensor to compensate for the temperature of the magnetic field detection signal.

6. The high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 1, characterized in that, The bottom wall of the guide cage is positioned opposite to the lower end air outlet of the inner guide pipe, and the space between the bottom of the guide cage and the lower end air outlet of the inner guide pipe serves as a guide cavity.

7. The high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 1, characterized in that, The monitoring chamber is connected to the monitoring tube via a monitoring connector. A first monitoring point is set on the monitoring tube and is connected to the low-pressure end of the differential pressure sensor. The monitoring tube is connected to the common end of the switching valve. The first end of the switching valve is connected to the outlet connector via a dry gas reference branch, and the second end is connected to the test gas connector via a pipeline. A safety check valve and a calibration throttling device are set on the dry gas reference branch. A second monitoring point is set on the pipeline between the calibration throttling device and the outlet connector. The second monitoring point is connected to the high-pressure end of the differential pressure sensor.

8. A method for operating a high-pressure gas backflow drying tube with bed and seal monitoring as described in any one of claims 1-7, characterized in that, include: The gas to be dried enters through the inlet of the inner guide tube and exits through the outlet. It then passes through the fixed sieve plate into the adsorbent bed, where it comes into contact with the adsorbent for drying. The dried gas then passes through the annular pressing sieve plate and enters the dry gas collection chamber, finally exiting at the bottom of the outer pressure pipe. During the operation of the drying tube, the pressure of the monitoring chamber is monitored in real time to determine whether the sealing ring has failed; at the same time, the position of the magnetic marker is monitored in real time to monitor the position of the adsorbent bed and determine the bed settling state.

9. The operating method of the high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 8, characterized in that, To determine whether the sealing ring has failed, the following steps are taken: The monitoring tube is connected to the dry gas reference branch through a switching valve. High-pressure gas with the same pressure as the dry gas manifold is depressurized by a calibrated throttling device and then input into the monitoring chamber. The differential pressure sensor collects the pressure difference between the second monitoring point and the first monitoring point in real time. When the pressure difference value is stable, neither of the two sealing rings has failed. When the pressure difference value continues to decrease, it is determined that the first sealing ring has leaked. When the pressure difference value continues to increase, it is determined that the second sealing ring has leaked. Determining the bed settlement status specifically includes: collecting magnetic field data of magnetic markers through a first magnetic field sensor and a second magnetic field sensor, converting the magnetic field data into position feature data, and determining the bed settlement status based on the position feature data.

10. The operating method of the high-pressure gas backflow drying tube with bed and seal monitoring as described in claim 8, characterized in that, During shutdown, the monitoring tube is connected to the test gas connector through the switching valve to deliver test gas into the monitoring chamber. Then, the monitoring tube is connected to the dry gas reference branch through the switching valve. The overall sealing performance of the two sealing rings is determined based on the change in the differential pressure sensor value.

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