A natural gas filter monitoring device, filter, and detection method

Abstract

This invention relates to the technical field of natural gas filters, specifically to a natural gas filter monitoring device, filter, and detection method. The monitoring device includes a rotating rod and a detection head; the detection head is disposed on the rotating rod; the rotating rod is rotatably mounted at the center of the top cover; the rotating rod is L-shaped, so that one side of the rotating rod extends between the filter element and the outer cylinder and can drive the detection head to rotate around the filter element; a camera and a supplementary light are installed inside the detection head. When the rotating rod rotates around its mounting axis, it can simultaneously drive the detection head to perform a circular motion around the filter element, ensuring that the detection head can cover the circumferential area of ​​the filter element. The camera clearly captures images of the filter element surface, and then, based on the shape, color, and other characteristics of the blockages in the images, accurately distinguishes between ice blockage, hydrocarbon blockage, and impurity blockage, fundamentally solving the core pain point that existing differential pressure monitoring methods cannot determine the cause of blockage, and providing a basis for subsequent accurate operation and maintenance.

Description

Technical Field

[0001] This invention relates to the technical field of natural gas filters, and more specifically, to a natural gas filter monitoring device, filter, and detection method. Background Technology

[0002] In current natural gas extraction and transportation scenarios, the application of filters has formed a standardized system: In the extraction stage, wellhead filters need to intercept mud, rock cuttings, and drilling fluid residues produced by the formation to prevent them from entering the gathering and transmission pipelines and causing blockages; in long-distance pipeline systems, station filters need to remove liquid water, condensate oil, and corrosion products such as iron oxide and ferrous sulfide carried in the gas flow, preventing the pipeline from experiencing accelerated corrosion or metering equipment from jamming; in LNG liquefaction plants and terminal receiving stations, precision filters need to control the particle size of impurities to below 5μm to meet the operating requirements of cryogenic heat exchangers. According to industry survey data, a complete long-distance natural gas pipeline system requires an average of 1-2 filters per 10 kilometers of pipeline, and a single large natural gas processing plant can have more than 50 filters, with their operation and maintenance costs accounting for 12%-15% of the total system operation and maintenance costs. In filter operation and maintenance management, determining the filter element blockage status is a core pain point. Under the current technological system, the industry generally adopts the "differential pressure monitoring method" as the basis for judgment: by installing pressure sensors at the inlet and outlet of the filter, the pressure difference between the two ends (i.e., differential pressure ΔP) is monitored in real time. When ΔP exceeds a preset threshold (usually 0.1-0.3 MPa, the specific value is adjusted according to the filter element precision and medium conditions), the system determines that the filter element is blocked, triggering a replacement or cleaning warning. This method, due to its simple principle, low cost, and fast response speed, has become the mainstream technology for filter operation and maintenance in the natural gas industry, with a current market penetration rate exceeding 95%. However, the "differential pressure monitoring method" has unavoidable technical limitations: it can only identify the blockage result, but cannot distinguish the cause of the blockage. The types of blockage in natural gas filters are significantly diverse, and the corresponding countermeasures vary greatly depending on the cause of the blockage.

[0003] Ice blockage: Water vapor in the airflow condenses into ice at low temperatures, forming ice crystals on the surface or inside the pores of the filter element, causing blockage. Heating is required to melt the ice crystals.

[0004] Hydrocarbon blockage: caused by the condensation of heavy hydrocarbon components in natural gas under low temperature and high pressure conditions, or by the formation of emulsions that adhere to the filter element.

[0005] Clogged with impurities: This is caused by the accumulation of solid mechanical impurities such as silt and sand from the ground, and corrosion products from pipelines. If the clogging is severe, the filter element must be replaced directly to ensure filtration effectiveness.

[0006] Because differential pressure signals can only reflect the macroscopic result of reduced filter element flow area and cannot identify the composition, morphology, and accumulation method of blockages, maintenance personnel find it difficult to formulate accurate response plans. In actual operation and maintenance, this technical deficiency has caused a series of problems: On the one hand, when the system triggers a differential pressure warning, maintenance personnel often choose to replace the filter element directly instead of using a cheaper cleaning method because they cannot determine the cause of the blockage. According to statistics, the over-replacement rate of filter elements caused by such misoperations is as high as 30%-40%, bringing billions of yuan in unnecessary costs to the industry every year; on the other hand, if scale blockage is misjudged as mechanical impurity blockage, backflushing not only fails to remove the scale layer, but may also cause the scale layer to break and enter downstream equipment, causing valve jamming or compressor cylinder scratches; more seriously, if microbial blockage is not identified in time, the acidic substances produced by bacterial metabolism will accelerate the corrosion and perforation of the filter element, causing unfiltered impurities to directly enter the system, leading to safety hazards such as pipeline corrosion and leakage.

[0007] In summary, existing filter blockage detection technologies based on differential pressure are no longer sufficient to meet the needs of the natural gas industry, especially the development of unconventional gas reservoirs, for precision and safety in operation and maintenance. Developing new monitoring technologies that can accurately identify the causes of blockages has become a key breakthrough direction for promoting the efficient operation of the natural gas industry chain. Summary of the Invention

[0008] The purpose of this invention is to provide a natural gas filter monitoring device, filter, and detection method, which can distinguish the causes of filter element blockage and thus assist in customizing a reasonable solution.

[0009] The embodiments of the present invention are achieved through the following technical solutions:

[0010] A natural gas filter monitoring device is used in conjunction with a filter; the filter includes an outer cylinder, a top cover, and a cylindrical filter element; the outer cylinder is provided with an inlet pipe, an outlet pipe, and a drain pipe; the outlet pipe extends to the center of the outer cylinder; the filter element is installed at the opening of the outlet pipe and located at the center of the outer cylinder; the top cover is detachably installed at an opening on the top of the outer cylinder; the monitoring device includes a rotating rod and a detection head; the detection head is disposed on the rotating rod; the rotating rod is rotatably installed at the center of the top cover; the rotating rod is L-shaped, such that one side of the rotating rod extends between the filter element and the outer cylinder and can drive the detection head to rotate around the filter element; a camera and a supplementary light are provided inside the detection head.

[0011] Furthermore, the rotating rod is provided with a sliding groove; the detection head is provided with a slider in conjunction with the sliding groove, so that the detection head can slide vertically along the filter element relative to the sliding groove; the rotating rod is also provided with a lifting motor and a lead screw in conjunction with the slider, so that the detection head is driven to rise and fall by the lifting motor.

[0012] Furthermore, the detection head also includes a housing; the housing is cylindrical with one end open; a glass plate is provided at the opening of the housing to enclose the camera and the fill light inside the housing; the slider is located at the end of the housing away from the opening.

[0013] Furthermore, the detection head is also provided with a plurality of heating lamps; the plurality of heating lamps are disposed inside the outer casing.

[0014] Furthermore, the rotation axis of the rotating rod extends through the top cover to the outside of the top cover; a rotating motor connected to the rotating rod is provided outside the top cover; a bearing and a sealing ring are provided between the rotating rod and the top cover.

[0015] Furthermore, a sealing cover is provided on the outside of the top cover so that the rotary motor and the rotary shaft are both sealed inside the sealing cover.

[0016] A natural gas filter includes a natural gas filter monitoring device; the inlet pipe is positioned at the center of the side of the filter element; the outlet pipe is fitted with an installation head to mount the filter element onto the installation head; the installation head and the outlet pipe are connected by a flexible hose, and support springs are evenly distributed around the installation head and between the outlet pipe and the outlet pipe.

[0017] A method for detecting a natural gas filter, using a natural gas filter, characterized by: scanning the outer wall of the filter element with a camera; extracting the average RGB color value of the blockage area, calculating the area, perimeter, and roundness of the blockage, and using LBP to extract the surface texture; if the blockage has high roundness and is crystalline, with uniform LBP value distribution showing a granular texture and an average RGB color value of R≈255, G≈255, B≈255, it is determined to be ice blockage; if the blockage has a large aspect ratio and is strip-shaped, with concentrated LBP values ​​showing a smooth oil film texture and an average RGB color value of R≈150, G≈100, B≈50, it is determined to be hydrocarbon blockage; if the blockage has low roundness and is irregularly fragmented, it is determined to be impurity blockage.

[0018] Furthermore, the detection head also includes a ranging sensor to detect the thickness of the blockage; if it is determined to be an ice blockage, the detection head moves to face the blockage location and irradiates the ice blockage location with a heating lamp until the blockage thickness is zero; if it is determined to be a hydrocarbon blockage, the detection head moves to face the blockage location and irradiates the hydrocarbon blockage location with a heating lamp until the blockage thickness no longer decreases.

[0019] Furthermore, after the filter element becomes clogged, a filter element vibration method is used in conjunction with it; the filter element vibration method is as follows: the detection head is repeatedly moved to face the air intake pipe and then moves away from the front of the air intake pipe; in the case of ice blockage and hydrocarbon blockage, the heating lamp irradiates the blockage area and the filter element vibration method is performed alternately; in the case of impurity blockage, only the filter element vibration method is performed.

[0020] The technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects:

[0021] When the rotating rod rotates around its mounting axis, it synchronously drives the detection head to move in a circular motion around the filter element, ensuring that the detection head covers the circumferential area of ​​the filter element. A high-definition camera and supplementary light are fixedly installed inside the detection head. The supplementary light provides sufficient light in the dim environment inside the filter, while the camera clearly captures images of the filter element surface. These images can be manually analyzed by maintenance personnel or automatically processed by an image recognition system. Based on the shape, color, and other characteristics of the blockages in the image, it can accurately distinguish between ice blockage, hydrocarbon blockage, and impurity blockage, fundamentally solving the core pain point that existing differential pressure monitoring methods cannot determine the cause of blockage, and providing a basis for subsequent precise maintenance.

[0022] By combining the rotational movement of the detection head around the filter element with the synergistic effect of vertical lifting and circumferential rotation, the detection head can capture images of the entire outer wall of the filter element without blind spots. This avoids incomplete identification of blockages due to missed detection areas, ensuring that blockages can be clearly captured regardless of whether they occur at the top, bottom, or any circumferential location of the filter element. At the same time, if the filter element surface is reflective, the shooting angle can be adjusted to ensure clear images, further improving the comprehensiveness and accuracy of monitoring.

[0023] The heating lamp has a dual function: Firstly, it can heat the ice-blocked areas on the filter element surface, causing the ice crystals to melt into water and be discharged through the drain pipe. Heating the hydrocarbon-blocked areas can cause the condensate or emulsion to evaporate or flow, assisting in the initial clearing of blockages. Secondly, since the filter may have a low-temperature environment, such as in LNG liquefaction plant scenarios or winter scenarios in high-latitude regions, water vapor can easily condense on the glass plate surface due to temperature differences, resulting in blurry images captured by the camera. The heating lamp can heat the glass plate to prevent water vapor formation, ensuring the clarity of the captured images and avoiding the impact of blurred vision on the judgment of the blockage type, further ensuring the reliability of monitoring.

[0024] The filter element has a certain degree of freedom of vibration. When the airflow impacts the filter element from the inlet pipe, the filter element can produce a small amount of shaking under the flexible constraint of the hose and the elastic action of the supporting spring. During the shaking process, some solid impurities, condensed water droplets and liquid hydrocarbons attached to the surface of the filter element can be dislodged by vibration and gravity, fall into the bottom of the outer cylinder and be discharged through the drain pipe, thereby realizing the self-cleaning of blockages, reducing the frequency of filter element replacement and reducing operation and maintenance costs. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the natural gas filter of the present invention.

[0026] Figure 2 for Figure 1 Enlarged view of point a in the middle.

[0027] Figure 3 This is a schematic diagram showing the connection between the detection head and the rotating rod.

[0028] Figure 4 This is a schematic diagram of the internal structure of the detection head.

[0029] Figure 5 This is a top view of the detection head.

[0030] Attached reference numerals: 1-Outer cylinder, 2-Top cover, 3-Filter element, 4-Inlet pipe, 5-Outlet pipe, 6-Drain pipe, 7-Rotating rod, 8-Camera, 9-Supplemental light, 10-Slider, 11-Lifting motor, 12-Lead screw, 13-Outer shell, 14-Glass plate, 15-Heating lamp, 16-Rotating motor, 17-Bearing, 18-Sealing ring, 19-Sealing cover, 21-Support spring, 22-Distance sensor, 23-Screw, 24-Hose. Detailed Implementation

[0031] like Figures 1-5 As shown, this invention provides a natural gas filter monitoring device, which needs to be used in conjunction with a filter. For example... Figure 1 As shown, the filter includes an outer cylinder 1, a top cover 2, and a cylindrical filter element 3. The outer cylinder 1 is equipped with an inlet pipe 4, an outlet pipe 5, and a drain pipe 6. The outlet pipe 5 extends to the center of the outer cylinder 1. The filter element 3 is installed at the opening of the outlet pipe 5 and located at the center of the outer cylinder 1. The top cover 2 is detachably installed at the top opening of the outer cylinder 1, providing a foundation for the installation and maintenance of the monitoring device. The core structure of the monitoring device is a rotating rod 7 and a detection head. The detection head is integrated on the rotating rod 7, which is rotatably installed at the center of the top cover 2. The overall design is L-shaped, which allows one side of the rotating rod 7 to extend into the gap area between the filter element 3 and the outer cylinder 1. When the rotating rod 7 rotates around its mounting axis, it can simultaneously drive the detection head to move in a circular motion around the filter element 3, ensuring that the detection head can cover the circumferential area of ​​the filter element 3. The detection head is internally equipped with a high-definition camera 8 and a supplementary light 9. The supplementary light 9 provides sufficient light in the dim environment inside the filter, while the camera 8 clearly captures images of the filter element 3 surface. These images can be manually analyzed by maintenance personnel or automatically processed by an image recognition system. Based on the shape, color, and other characteristics of the blockages in the images, it accurately distinguishes between ice blockage, hydrocarbon blockage, and impurity blockage, fundamentally solving the core pain point of existing differential pressure monitoring methods that cannot determine the cause of blockage, and providing a basis for subsequent precise maintenance. Specifically, ice blockage presents as ice crystals; hydrocarbon blockage presents as an oil film or strips; and impurity blockage presents as irregular fragments.

[0032] In this embodiment, a groove extending along the length of the rotating rod 7 is provided on the rod body. A slider 10 is fixedly provided at the position of the detection head corresponding to the groove. The slider 10 can be embedded in the groove and slide along the groove, thereby realizing the movement of the detection head relative to the rotating rod 7 in the vertical direction of the filter element 3. Specifically, as shown below... Figure 3 and Figure 4 As shown; simultaneously, the rotating rod 7 is also equipped with a lifting motor 11 and a lead screw 12. The lead screw 12 is threadedly connected to the slider 10, and the output shaft of the lifting motor 11 is driven by the lead screw 12. When the lifting motor 11 is started, it can drive the lead screw 12 to rotate, thereby driving the slider 10 to move up and down along the slide groove, ultimately realizing the vertical lifting and lowering of the detection head. Combined with the rotational movement of the detection head around the filter element 3, the synergistic effect of vertical lifting and circumferential rotation allows the detection head to capture the entire outer wall of the filter element 3 without blind spots, avoiding the problem of incomplete blockage identification caused by missed detection areas, ensuring that no matter whether the blockage occurs in the upper part, lower part, or any circumferential position of the filter element 3, it can be clearly captured; at the same time, if the surface of the filter element 3 is reflective, the shooting angle can be adjusted to ensure clear shooting, further improving the comprehensiveness and accuracy of monitoring.

[0033] In this embodiment, the detection head is equipped with a housing 13. The housing 13 is a cylindrical structure with one open end, facing the filter element 3, so that the camera 8 can capture images of the filter element 3 through the opening. A transparent glass plate 14 is sealed at the opening of the housing 13, and the glass plate 14 is sealed with the housing 13 using sealant, completely enclosing the camera 8 and the supplementary light 9 inside the housing 13. The slider 10 is fixedly installed at the end of the housing 13 away from the opening, ensuring that the cooperation between the slider 10 and the groove does not affect the shooting angle of the detection head. Because the internal environment of the filter is complex, containing substances such as silt, condensate oil, and water vapor carried by the natural gas flow, if the camera 8 and the supplementary light 9 are directly exposed to this environment, they are easily contaminated by impurities or damaged by corrosive substances. The design of the closed housing 13 and the transparent glass plate 14 can not only ensure that the camera 8 can clearly capture images of the filter element 3, but also effectively isolate the complex internal airflow, preventing the camera 8 and the supplementary light 9 from directly contacting impurities, significantly extending the service life of the core components of the detection head, and ensuring the long-term stable operation of the monitoring device.

[0034] Furthermore, several heating lamps 15 are added to the detection head. These lamps are evenly distributed inside the housing 13, and their illumination direction is all directed towards the filter element 3, ensuring that the light can cover the clogged areas on the glass plate 14 and the surface of the filter element 3. The heating lamps 15 employ far-infrared radiation heating technology, generating heat energy through tungsten filament or carbon fiber heating elements, and transferring the heat to the target area in the form of electromagnetic waves. This method features rapid heating, high thermal efficiency, and strong penetration. This heating method can precisely target the surfaces of the filter element 3 and the glass plate 14, avoiding overheating of other components of the filter.

[0035] The heating lamp 15 has a dual function: on the one hand, it can heat the ice blockage area on the surface of the filter element 3, causing the ice crystals to melt into water and be discharged through the drain pipe 6. Heating the hydrocarbon blockage area can cause the condensate oil or emulsion to evaporate or flow, assisting in the initial cleaning of the blockage. On the other hand, since there may be a low-temperature environment inside the filter, such as in LNG liquefaction plant scenarios or winter scenarios in high-latitude regions, the surface of the glass plate 14 is prone to condensation of water mist due to temperature differences, resulting in blurry images captured by the camera 8. The heating lamp 15 can heat the glass plate 14 to prevent water mist formation, ensure the clarity of the captured images, avoid the impact of blurred vision on the judgment of the blockage type, and further ensure the reliability of monitoring.

[0036] In this embodiment, the rotation shaft of the rotating rod 7 passes through the top cover 2 and extends to the outside of the top cover 2. A rotary motor 16 is fixedly installed on the outside of the top cover 2. The output shaft of the rotary motor 16 is connected to the rotation shaft of the rotating rod 7 via a coupling. By rotating the rotary motor 16 in both directions, the rotation angle and speed of the rotating rod 7 can be precisely controlled, enabling the detection head to rotate controllably around the filter element 3. Simultaneously, a bearing 17 and a sealing ring 18 are fitted at the point where the rotating rod 7 passes through the top cover 2. The bearing 17 is a high-temperature resistant and wear-resistant rolling bearing, which reduces frictional resistance during the rotation of the rotating rod 7, ensuring smooth and stable rotation. The sealing ring 18 is made of fluororubber material that is resistant to oil and natural gas corrosion, tightly fitting the gap between the rotating rod 7 and the top cover 2. This effectively prevents natural gas inside the filter from leaking through the gap between the rotating shaft and the top cover 2, avoiding safety hazards caused by gas leakage. It also prevents external impurities from entering the filter, ensuring the normal operation of the filtration system.

[0037] Furthermore, a sealing cover 19 is added to the outside of the top cover 2. The sealing cover 19 is made of stainless steel and its bottom is fixed to the top cover 2 by bolts. A sealing gasket is provided at the connection point to completely seal the connection between the rotating motor 16, the rotating shaft and the top cover 2 inside the sealing cover 19. The design of the sealing cover 19 has a dual function. First, it protects the rotating motor 16 from the influence of the external environment. Natural gas extraction and transportation sites often have wind, sand, rain, corrosive gases, etc. The sealing cover 19 can prevent these substances from corroding the rotating motor 16, avoiding motor failure and extending the service life of the motor. Second, it forms a double sealing structure. Combined with the aforementioned sealing ring 18, the sealing cover 19 can further isolate the external air from the gas inside the filter. Even if the sealing ring 18 shows slight aging, the sealing cover 19 can still play a secondary protection role, significantly improving the sealing and safety of the entire device and adapting to the complex working environment on site.

[0038] This embodiment also provides a natural gas filter that integrates the aforementioned monitoring device and optimizes its structure to improve the blockage removal effect. The inlet of the inlet pipe 4 is positioned directly opposite the center of the side of the filter element 3. When natural gas enters the gap between the filter outer cylinder 1 and the filter element 3 from the inlet pipe 4, the airflow can directly impact the central area of ​​the side of the filter element 3, forming a stable airflow channel. An installation head is provided on the outlet pipe 5 corresponding to the position of the filter element 3. The filter element 3 is fixed to the installation head by a screw 23. The installation head and the outlet pipe 5 are connected by a flexible hose 24. Four to six support springs 21 are evenly distributed around the installation head and between it and the outlet pipe 5. The two ends of each support spring 21 are fixedly connected to the installation head and the outlet pipe 5, respectively. This structural design allows the filter element 3 a certain degree of vibration freedom. When the airflow impacts the filter element 3 from the intake pipe 4, the filter element 3 can generate a small amount of shaking under the flexible constraint of the hose 24 and the elastic action of the support spring 21. During the shaking process, some solid impurities, condensed water droplets and liquid hydrocarbons attached to the surface of the filter element 3 can be dislodged by vibration and gravity, fall into the bottom of the outer cylinder 1 and be discharged through the drain pipe 6, thereby realizing the self-cleaning of blockages, reducing the replacement frequency of the filter element 3 and reducing maintenance costs.

[0039] This invention also provides a method for detecting a natural gas filter. This method accurately determines the type of blockage through image feature analysis: First, the rotary motor 16 and the lifting motor 11 are started, causing the detection head to rotate circumferentially and move vertically around the filter element 3. The camera 8 performs a full scan and captures a high-definition image of the surface of the filter element 3. Subsequently, feature extraction is performed on the captured image. When extracting the RGB color mean of the blockage area, the system uses the pixel analysis algorithm built into the image software to automatically locate the blockage area and traverse all pixels in the area. The sum of the values ​​of the red, green, and blue channels is calculated separately and then divided by the total number of pixels to obtain the RGB color mean of the area, thereby quantifying the color characteristics of the blockage.

[0040] When calculating the area and perimeter of a blockage, the system first identifies the blockage boundary using an edge detection algorithm and marks the pixels on the boundary. The blockage area is obtained by counting the number of pixels within the boundary and converting the pixel count into an actual area value according to a pre-set conversion ratio between pixels and actual area. The perimeter is calculated by adding up the Euclidean distances between adjacent pixels on the boundary. The roundness is calculated using the formula "roundness = 4π × area / perimeter²" based on the obtained area and perimeter data. This value directly reflects how close the blockage shape is to a circle; the closer the value is to 1, the closer the blockage shape is to a circle.

[0041] For extracting surface texture features of blockages, the Local Binary Pattern (LBP) algorithm is employed. This algorithm selects a fixed-size neighborhood (e.g., an 8-neighborhood) centered on each pixel in the blockage image. The grayscale value of the center pixel is used as a threshold, and the values ​​are compared sequentially with the grayscale values ​​of all pixels within the neighborhood. If a neighboring pixel's grayscale value is greater than or equal to the threshold, it is marked as 1; otherwise, it is marked as 0, resulting in an 8-bit binary number. This binary number is then converted to decimal and used as the LBP value of the center pixel. By traversing all pixels in the blockage image, the LBP value distribution of the entire blockage region can be obtained. This distribution effectively reflects the surface roughness, particle distribution uniformity, and other texture features of the blockage.

[0042] The blockage type is determined based on the feature extraction results: if the blockage has a high roundness (≥0.8), is crystalline, has a uniform LBP value distribution (granular texture), and the average RGB color value is close to R≈255, G≈255, B≈255 (i.e., white), it is identified as ice blockage; if the blockage has a large aspect ratio (usually ≥3), is strip-shaped or oily film-like, has concentrated LBP values ​​(smooth texture), and the average RGB color value is close to R≈150, G≈100, B≈50 (i.e., brownish-yellow), it is identified as hydrocarbon blockage; if the blockage has a low roundness (≤0.5), is irregularly fragmented, and has a rough and uneven texture, it is identified as impurity blockage. This method achieves accurate blockage type identification through quantified image features, completely solving the problem that existing differential pressure methods cannot distinguish the cause of blockage, avoiding problems such as excessive replacement of filter element 3 and damage from excessive flushing of equipment due to misjudgment, and significantly improving the accuracy of operation and maintenance.

[0043] Furthermore, a function for monitoring and targeted treatment of blockage thickness has been added: the detection head also integrates a laser rangefinder 22, with the emitting end of the rangefinder 22 facing the surface of the filter element 3. It can measure the distance between the detection head and the blockage on the surface of the filter element 3 in real time, and then calculate the thickness of the blockage, that is, the difference between the initial distance to the surface of the filter element 3 and the distance after blockage. Different heating treatments are adopted according to different types of blockage: if it is determined to be ice blockage, the detection head is moved to face the blockage position by the lifting motor 11 and the rotating motor 16, and the heating lamp 15 is turned on to irradiate the ice blockage area. At the same time, the blockage thickness is monitored in real time by the rangefinder 22 until the blockage thickness drops to zero. At this time, the ice crystals are completely melted, and heating is stopped. If it is determined to be hydrocarbon blockage, the detection head is also aligned with the blockage position and the heating lamp 15 is turned on. Since hydrocarbons soften, volatilize or flow when heated, when the rangefinder 22 detects that the blockage thickness no longer decreases, it indicates that the cleanable hydrocarbons have been basically removed, and the residual part cannot be cleaned. At this time, heating is stopped. This design, through precise thickness monitoring and targeted heating, avoids energy waste caused by overheating or incomplete cleaning due to insufficient heating. Simultaneously, the heating lamp 15 directly targets the clogged area, improving the efficiency of handling ice and hydrocarbon blockages and reducing damage to the filter element 3. Furthermore, it can monitor the thickness of impurities, aiding in the planning of filter element 3 replacement schedules.

[0044] Furthermore, a vibration-assisted cleaning method for filter element 3 is provided, which is implemented in conjunction with the movement of the detection head: when filter element 3 becomes clogged, the detection head is controlled to move vertically and circumferentially, repeatedly moving to block the airflow in front of the inlet of the air inlet pipe 4, and then moving away from the in front of the air inlet pipe 4. When the detection head blocks the air inlet pipe 4, the airflow cannot directly impact the filter element 3, and the filter element 3 returns to its original position under the action of the support spring 21; when the detection head moves away, the airflow impacts the filter element 3 again, and the filter element 3 tilts and swings under the impact force of the airflow. Under the combined action of the impact force and the elastic force of the support spring 21, the filter element 3 vibrates, and the vibration frequency can be adjusted by adjusting the frequency of the detection head blocking and moving away. Depending on the type of blockage, the vibration method is used in conjunction with heating: for ice blockage and hydrocarbon blockage, the heating lamp 15 is used to alternately irradiate and the filter element 3 vibrates. Heating softens or melts the blockage, and vibration accelerates its removal, improving cleaning efficiency. For blockages caused by impurities, which are mostly solid debris, heating has little effect. Therefore, only the vibration method of filter element 3 is applied. Vibration dislodges some loosened impurities, reducing their accumulation and slowing down the clogging rate of filter element 3. This vibration method eliminates the need for a complex additional vibration mechanism, utilizing the movement of the detection head and existing airflow and spring structures. Its simple structure and low cost further enhance the convenience and effectiveness of blockage cleaning, reduce the frequency of filter element 3 replacements, and lower maintenance costs.

Claims

1. A natural gas filter detection method, which is used in combination with a natural gas filter; the natural gas filter comprises an outer cylinder, a top cover and a cylindrical filter core; the outer cylinder is provided with an air inlet pipe, an air outlet pipe and a blowdown pipe; the air outlet pipe extends to the center of the outer cylinder; the filter core is installed at the pipe opening of the air outlet pipe and located at the center of the outer cylinder; the top cover is detachably installed at the opening of the top of the outer cylinder; characterized in that: The outer cylinder is internally provided with a monitoring device; the monitoring device comprises a rotating rod and a detection head; the detection head is arranged on the rotating rod; the rotating rod is rotatably arranged at the center of the top cover; the rotating rod is L-shaped, so that one side of the rotating rod extends between the filter element and the outer cylinder and can drive the detection head to rotate around the filter element; the detection head is internally provided with a camera and a fill light; The natural gas filter detection method is that the camera scans the outer wall of the filter element; the RGB color mean value of the blocked area is extracted, the area, perimeter and circularity of the blockage are calculated, and the surface texture is extracted by LBP; if the blockage circularity is high and crystalline, the LBP value distribution is uniform and granular texture, and the RGB color mean value is R≈255, G≈255, B≈255, it is judged as ice blockage; if the blockage aspect ratio is large and strip-shaped, the LBP value is concentrated and smooth oil film texture, and the RGB color mean value is R≈150, G≈100, B≈50, it is judged as hydrocarbon blockage; if the blockage circularity is low and irregular debris, it is judged as impurity blockage.

2. The natural gas filter detection method of claim 1, wherein: The rotating rod is provided with a sliding groove; the detection head is provided with a sliding block matched with the sliding groove, so that the detection head can slide along the vertical direction of the filter element relative to the sliding groove; the rotating rod is further provided with a lifting motor and a screw rod matched with the sliding block, so that the detection head is driven to lift by the lifting motor.

3. The natural gas filter detection method of claim 2, wherein: The detection head further comprises an outer shell; the outer shell is in the shape of a cylinder with one end open; a glass plate is arranged at the opening of the outer shell to enclose the camera and the fill light inside the outer shell; The sliding block is arranged at one end of the outer shell away from the opening.

4. The natural gas filter detection method of claim 3, wherein: The detection head is further provided with a plurality of heating lamps; a plurality of heating lamps are arranged inside the outer shell.

5. The natural gas filter detection method of claim 4, wherein: The rotating shaft of the rotating rod extends through the top cover to the outside of the top cover; the outside of the top cover is provided with a rotating motor connected to the rotating rod; a bearing and a sealing ring are arranged between the rotating rod and the top cover.

6. The natural gas filter detection method of claim 5, wherein: The outside of the top cover is further provided with a sealing cover, so that the rotating motor and the rotating shaft are all sealed inside the sealing cover.

7. The natural gas filter detection method of claim 6, wherein: The air inlet pipe is opposite to the center position of the side surface of the filter element; the air outlet pipe is provided with a mounting head matched with the filter element, so that the filter element is mounted on the mounting head; the mounting head and the air outlet pipe are connected by a hose, and the mounting head and the air outlet pipe are uniformly provided with supporting springs around.

8. The natural gas filter detection method of claim 7, wherein: The detection head further comprises a distance measuring sensor to detect the thickness of the blockage; if it is determined that the blockage is ice, the detection head moves to the position opposite to the blockage and irradiates the ice blockage position by the heating lamp until the blockage thickness is zero; if it is determined that the blockage is hydrocarbon, the detection head moves to the position opposite to the blockage and irradiates the hydrocarbon blockage position by the heating lamp until the blockage thickness no longer decreases.

9. The natural gas filter detection method of claim 8, wherein: After the filter element is blocked, the filter element vibration method is used in cooperation; the filter element vibration method is that the detection head repeatedly moves to the air inlet pipe and then leaves the front of the air inlet pipe; when the blockage is ice or hydrocarbon, the heating lamp irradiates the blockage position and the filter element vibration method is alternately executed; when the blockage is impurity, only the filter element vibration method is executed.

Images