A unit structure for preliminary enrichment and separation of low-concentration methane from coalbed methane

Abstract

A device unit structure for the preliminary enrichment and separation of low-concentration methane from coalbed methane consists of an inlet pipe section, an outlet pipe section, and a three-layer enrichment and separation section composed of a composite body, a rotating cover layer, and an exhaust cover layer. The rotating cover layer has ribs on its inner wall, a movable partition whose flaps expand and contract to switch the composite body between a cage and a water bottle form, and a fan structure outside the bottom circumferential hole covered with a selectively permeable membrane. These structures facilitate the generation of a three-dimensional gas vortex within the device unit by the mixed component gases. Non-methane components surrounding the central axis of the cyclone are drawn to the exterior of the device unit structure via the fan structure, while methane gas enriched in the central axis is trapped by the partition structure and enters the outlet pipe section, thereby achieving the preliminary enrichment and separation of low-concentration methane from coalbed methane. The device unit structure has simple components, requires no chemical treatment, is easy to assemble and apply, and has great potential for technological promotion.

Description

Technical Field

[0001] The present invention relates to a device unit structure for preliminarily enriching and separating low-concentration methane in coalbed methane, namely, a device unit that enhances the enrichment of low-concentration methane components in coalbed methane and preliminarily separates them from air and carbon dioxide gas through a structure that integrates the functions of rotary separation, zoning isolation, central column centralized collection, bottom fan release and suction and external discharge. The present invention belongs to the field of unconventional natural gas exploration and development engineering equipment. Background Art

[0002] Coalbed methane (CBM) is a new type of clean energy with a high calorific value. Its effective development and utilization is of great practical significance for reducing coal mine gas disasters, alleviating the contradiction between energy supply and demand, improving energy structure, enhancing the atmospheric environment, and promoting coordinated and sustainable social and economic development.

[0003] In the context of rapid economic development, tight energy supply, and increasing pressure on environmental protection and coal mine production safety in my country, the initial enrichment and separation of low-concentration methane in coalbed methane containing large amounts of carbon dioxide, oxygen, and nitrogen is a core issue in the comprehensive development and utilization of coalbed methane. The equipment and device units for enriching and separating low-concentration methane in coalbed methane are also the focus of research, design, and developers. Summary of the Invention

[0004] The problem to be solved by the present invention is to provide a device unit structure for preliminary enrichment and separation of low-concentration methane in coalbed methane. With the help of rotating components and partition components, methane and non-methane components with density differences in coalbed methane are isolated according to their distribution areas. At the same time, with the help of the fan structure outside the bottom circumferential hole of the rotating component covered with a selective permeable membrane, the carbon dioxide, oxygen, and nitrogen heavy component gases isolated in the periphery are released to the suction and discharge area, and the isolated and enriched methane gas in the central axis area of ​​the device unit structure is output through the outlet.

[0005] The technical solution adopted by the present invention to solve its technical problems is:

[0006] The main body of the unit structure of the device consists of three sections, namely the air inlet pipe section, the air outlet pipe section, and the three-layer enrichment and separation section composed of the inverted bowl body and the mobile partition complex, the gradually expanding and closing rotating cover layer, and the external exhaust cover layer. Among them, the three-layer structure of the three-layer enrichment and separation section is coaxial and integrated; the layers between the three-layer enrichment and separation section serve as the partition area, which are, from the inside to the outside, the methane enrichment area, the non-methane component enrichment and release area, and the non-methane component external exhaust area; the partition belt between the methane enrichment area and the non-methane component enrichment and release area is a foldable movable partition; when the folding piece of the movable partition is fully folded, the movable partition, the inverted bowl body, and the upper buckle are combined into a cage-shaped body, and the methane and non-methane component gases are in a state to be enriched and separated. Under the rotation of the arc-shaped ribs on the inner wall of the gradually expanding and closing rotating cover layer, the methane and non-methane component gases generate three-dimensional gas vortexes, and based on the density difference of each component in the coalbed methane, the methane Under the gas vortex, the central axis of the rotation is located, while the non-methane components in the coalbed methane are located on the periphery of the central axis. When the movable partition flaps are fully expanded, they form a water bottle body. The interior of the enclosed area is the methane enrichment zone, and the area between the enclosed area and the gradually expanding rotary cover layer is the non-methane enrichment and release zone. Gas in the non-methane enrichment and release zone sinks through the gradually expanding rotary cover layer, passing through the selectively permeable membrane at the bottom circumferential holes along the mouth. When the fan structure is expanded, it is released into the suction and discharge area. There, it is sucked out of the device unit structure through the outlet located on the upper side wall of the suction and discharge area between the discharge cover layer and the gradually expanding rotary cover layer. Under the gas vortex, methane gas in the rotating central axis is enriched and enters the gas outlet section of the device unit structure through the enclosed area formed by the movable partition when the flaps are fully expanded, thereby achieving preliminary enrichment and separation of low-concentration methane in the coalbed methane.

[0007] The above-mentioned intake pipe section consists of a lower buckle ring and an intake pipe section. The lower buckle ring is composed of a locking surface and a locking ring. The intake pipe section is a flexible and pressure-elastic pipe band. The locking ring of the lower buckle ring is a cylindrical ring, and the inner wall of the cylindrical surface of the cylindrical ring is processed with threads. The locking surface of the lower buckle ring is a gradually expanding arc surface or an inclined plane circular ring. The inner diameter of the locking surface circular ring is consistent with the inner diameter of the locking ring cylindrical ring, and the outer diameter of the locking surface circular ring is larger than the locking ring cylindrical ring. The large-mouth end face of the lower buckle ring locking surface has an inner circumference integrally formed and connected with one end of the lower buckle ring locking ring cylindrical ring. The intake pipe section is a flexible circular tube, and the ports at both ends of the circular tube are respectively embedded with a port cylindrical ring and a circular ring. The port of the embedded circular ring is on the side of the small end face of the lower buckle ring locking surface and is integrally formed and connected with the inner circumference of the lower buckle ring locking surface circular ring. The port of the embedded cylindrical ring is processed with threads on the outer wall of the cylindrical ring cylindrical surface for connecting with other pipe sections with matching pipe diameters and processed with internal threads.

[0008] The main components of the three-layer enrichment and separation section are, from the inside out, the composite body, the rotating cover layer, and the outer exhaust cover layer. All three layers are coaxial with the intake pipe section. The upper auxiliary components of the three-layer enrichment and separation section main components are composed of the upper buckle ring and valve A.

[0009] The upper retaining ring is the component that connects the three-layer enrichment and separation section to the intake pipe section. It consists of a locking surface and a locking ring. The upper retaining ring locking ring is a cylindrical ring with an external thread machined on the outer wall of the cylindrical ring to match the internal thread of the lower retaining ring locking ring of the intake pipe section. The inner diameter of the upper retaining ring locking ring matches the outer diameter of the inverted bowl port of the three-layer enrichment and separation section complex. One end of the upper retaining ring is integrally connected to the three-layer enrichment and separation section complex, and the other end is integrally connected to the upper retaining ring locking surface. The locking surface of the upper buckle ring is a gradually expanding arc surface or an inclined plane ring, and the curvature of the arc surface or the slope of the inclined plane is consistent with the locking surface of the lower buckle ring of the intake pipe section. The inner diameter of the upper buckle ring locking surface is consistent with the inner diameter of the locking ring cylindrical ring, and the outer diameter of the locking surface ring is larger than the locking ring cylindrical ring, so as to ensure that in the process of threaded docking between the upper buckle ring of the three-layer enrichment and separation section and the lower buckle ring of the intake pipe section, the locking surfaces of the upper and lower buckle rings can press the flexible circular tube of the intake pipe section, thereby realizing the sealing closure between the intake pipe section and the three-layer enrichment and separation section; on one side of the large end face of the upper buckle ring locking surface, the inner circumference of the ring is integrated with one end of the cylindrical ring of the upper buckle ring locking ring.

[0010] Valve A is assembled inside the cylindrical ring of the upper retaining ring. The valve core of valve A is empty or can be loaded with a water filter membrane or a water attachment membrane depending on the operating environment. A empty valve core means that there are no special requirements for the gas inside the device unit; the water filter membrane is used to meet the device unit's internal gas dryness requirements; the water attachment membrane is used to meet the device unit's internal requirement for charging humid gas when an additional current is applied.

[0011] The composite body is a component in which an inverted bowl-shaped body and a rotating movable partition of a ring column are combined up and down.

[0012] The bowl body has no covers at either end of its rim or bottom, and is composed of a neck and a frustum. The neck and frustum are coaxial and coaxial with the air intake section. The neck is a cylindrical surface, and the outer diameter of the neck cylindrical surface is consistent with the inner diameter of the upper buckle ring lock ring. The height of the neck cylindrical surface is greater than the height of the upper buckle ring lock ring cylindrical surface, and one end of the neck cylindrical surface is integrally connected to the inner wall of the upper buckle ring lock ring cylindrical surface. The other end of the neck cylindrical surface is consistent with the inner diameter of the small end of the frustum of the composite inverted cone and is integrally connected to the small end of the frustum. Before the two end surfaces of the neck are integrally connected to the upstream and downstream components, the lower buckle ring of the air intake section is sleeved onto the outer periphery of the neck, so that the lower buckle ring of the air intake section has an upper limit of movement within the neck of the bowl body, the upper limit being the connection line between the locking surface of the lower buckle ring and the lock ring, and the lower limit being the connection line between the neck of the bowl body and the frustum. The frustum is the side wall of a truncated cone, with the small end of the frustum facing the neck and the large end facing the movable partition. The gradually expanding side wall of the frustum ensures that the gas can fully diffuse within the area when it passes through the air inlet pipe section and the neck of the composite bowl body and enters the three-layer area of ​​the three-layer enrichment and separation section body.

[0013] The movable partition is a foldable component consisting of a cylindrical frame, folding pieces, magnetic seals, and extension tubes. The cylindrical frame consists of an upper ring rail, a lower ring rail, and a vertical rod. The upper and lower ring rails are vertically opposed and coaxial with the air intake section. The upper and lower ring rails are circular rails of equal size, and the rail size is consistent with the end face of the large end of the cone part of the inverted bowl. The rail teeth of the upper and lower ring rails face downward and upward respectively, and the back of the rail teeth are integrally formed and connected to the end face of the large end of the cone part of the inverted bowl and the end face of the large end of the outer cover layer of the three-layer enrichment and separation section. In the vertical direction, the upper and lower ring rails are supported and connected by vertical poles, that is, the two ends of the vertical poles are vertically connected to the upper and lower ring rails respectively, the number of vertical poles is greater than or equal to 2, and the connection points between the vertical poles and the ring rails divide the circumference of the ring rails equally; the vertical poles are cylindrical to reduce the vibration degree of the gas vortex on the frame; in the vertical direction, the height of the vertical poles matches the height of the folding pieces that are integrally connected to them and can form movable partitions, that is, the folding pieces start with the vertical poles and slide along the ring rails to expand and close. The number of folding pieces of the movable partition is consistent with the number of uprights, that is, a folding piece can be stretched out from the side of each upright and move in a circle along the ring track; the folding piece is a corrugated profile or other folding profile, and the folding bones in the folding piece are rigid materials, and several parallel folding bones are embedded in the folding piece, and the folding bones are perpendicular to the stretching direction of the folding piece; the two ends of the rigid folding bone are each equipped with a rigid rail core, and the shape of the rail core is not restricted, but under the control of an external control device, the rail core is required to make synchronous and smooth movement in the same direction in the track teeth of the upper and lower ring tracks. During the movement, the folding bones of the folding piece are always parallel to the uprights of the movable partition, that is, no matter whether the rail core is driven by external electric, electromagnetic or mechanical transmission, it is necessary to ensure that the folding piece is driven by the rigid folding bone to expand and close smoothly along the upper and lower ring tracks of the frame of the movable partition; a semi-solidified oil seal is used between the rail core and the ring track to avoid The gas passes through the gap between the track core and the ring track; the length of the folding piece in the maximum expanded state at least meets the arc length between the two adjacent vertical poles on the side wall of the annular cylinder formed by running along the ring track, that is, when all the folding pieces are expanded to the maximum, the folding pieces and the vertical poles will transform the annular column frame of the mobile partition into an annular column with a side wall in a closed state. At this time, the mobile partition is combined with the inverted bowl body and the upper buckle into a water bottle body, and the folding piece in the maximum retracted state will make the mobile partition, the inverted bowl body and the upper buckle into a cage-shaped body; the other end of the folding piece that is not integrally connected to the vertical pole is equipped with a magnetic seal strip that is the same length as the folded bone and parallel to the folded bone. When the folding piece is expanded along the ring track from the vertical pole integrally connected to it and contacts the adjacent vertical pole, the magnetic seal strip and the adjacent vertical pole are magnetically adsorbed to ensure that the two adjacent vertical poles are closed. The materials and assembly of the vertical pole and the magnetic seal strip adopt conventional electromagnetic and magnetic attraction principles.The expansion tube is a hollow tube with no restrictions on the cross-sectional shape of the tube. The number of expansion tubes is consistent with the number of vertical poles, and the material and size specifications of all expansion tubes must be the same; the expansion tubes are parallel to the vertical poles and are integrally connected and fixed to the lower part of the vertical poles, and are distributed in the closed body formed by the movable partition; according to the needs of the device unit, the interior of the expansion tube is assembled with circuits, concentration monitors, and electrode plates. If there are no special requirements, the interior of the expansion tube is only assembled with circuits, and the interior of the expansion tube is allowed to be empty.

[0014] The rotating cover layer is a cap-shaped component with a gradually expanding bottom circumference. It consists of a gradually expanding surface, a rim, ribs, an upper inner ring rail, a lower inner ring rail, and a sash window. The rotating cover layer is coaxial with the air intake section. The gradually expanding surface of the rotating cover layer is the side wall of a truncated cone; the outer diameter of the small end of the truncated cone surrounded by the gradually expanding surface is integrally formed and connected to the upper inner ring rail. The upper inner ring rail is a hollow or solid annular body. Driven by electric, electromagnetic or mechanical transmission, it cooperates with the upper outer ring rail in the outer discharge cover layer of the three-layer enrichment and separation section; the inner wall of the gradually expanding surface is integrally formed with spiral ribs. When the gradually expanding surface rotates around the axis, the space area inside the gradually expanding surface will generate a three-dimensional gas vortex. When the frame folds of the movable partition are in the maximum retracted state, the cage-shaped body The movable partition is in a non-enclosed state, and the methane and non-methane component gases in the coalbed methane with a large density difference are regularly distributed in the three-dimensional gas vortex. Under the installation conditions that the small end of the cone surrounded by the gradually expanding surface is at the top and the large end is at the bottom, the methane gas with lower density is concentrated in the central axis position of the entire interior of the rotating cover layer and moves toward the small end of the cone surrounded by the gradually expanding surface, while the non-methane component gases with higher density are concentrated in the outer area of ​​the central axis position of the interior of the rotating cover layer and move toward the large end of the cone surrounded by the gradually expanding surface.The edge of the rotating cover layer is located at the brim of the cap-shaped rotating cover layer, that is, under the installation condition that the small end of the truncated cone surrounded by the gradually expanding surface of the rotating cover layer is at the top and the large end is at the bottom, the edge is the gradually expanding bottom circumferential closing area of ​​the rotating cover layer, which is composed of an upper edge surface and a lower edge surface, and the vertical projections of the upper and lower edge surfaces of the edge are both circular rings; the upper and lower edge surfaces of the edge are both circular arc surfaces or inclined planes, and the upper and lower edge surfaces of the edge are gradually expanding and gradually contracting respectively, and the large port of the upper edge surface is consistent in size with the large port of the lower edge surface and is integrally formed and connected; the small end of the upper edge surface of the edge is consistent in size with the large end of the gradually expanding surface And it is connected by integrated molding, and the generatrix formed by the intersection of the plane where the central axis of the edge is located and the upper and lower edges is a broken line. The broken line angle formed in the direction inward toward the center of the edge is less than 180 degrees, that is, after the edge gradually expands, the gradual expansion of the rotating cover layer is first increased through the upper edge of the edge, and then the bottom edge is closed inward through the lower edge of the edge. This shape promotes the non-methane component gas with higher density in the coalbed methane in the three-dimensional vortex state to be enriched in the inner area of ​​the bottom edge close to the wall, just like a safe harbor area that can avoid the formation of further disturbance to the non-methane component gas to a certain extent. The intersection line between the upper and lower edges of the bead is circular, and the outer diameter of the circle is smaller than the inner diameter of the intersection line of the circle produced by the plane where the circle is located and the outer cover layer of the three-layer enrichment and separation section, that is, as the maximum size of the bead, the intersection position between the upper and lower edges of the bead and the inner wall of the outer cover layer of the three-layer enrichment and separation section still maintain a certain spatial area; the lower edge of the bead is evenly distributed along the circumference with circular holes of the same specification, namely bottom circumferential holes, and there are multiple holes, and the hole mouth is covered with a membrane, which is a selective permeable membrane, so that the non-methane component gas in the area between the isolation trap and the rotating cover layer passes through The membrane is transported to the area between the rotating cover layer and the outer cover layer. Methane gas blocked by the membrane is rotated again when the mobile fault flaps close, increasing its chance of being present as methane-enriched gas within the mobile isolation trap. The small end of the lower edge of the bead is integrally connected to the lower inner rail. The lower inner rail is a hollow or solid annular ring. Driven by electrical, electromagnetic, or mechanical transmission, it mates with the lower outer rail on the bottom surface of the outer cover layer of the three-layer enrichment and separation section. The lower inner rail serves as the core of the lower outer rail on the bottom surface of the outer cover layer, rotating within the track teeth of the lower outer rail. The small end of the lower edge of the bead is the bottom surface of the rotating cover layer, which is actually the bottom surface of the outer cover layer. The upper inner rail of the rotating cover layer's expanding surface and the lower inner rail of the bead rotate in the same direction and at the same angular velocity.At the bottom peripheral hole of the lower edge of the rim, a feather fan window is integrated on the outer wall of the rim. The feather fan window consists of a window frame, a connecting shaft and fan blades. The surface where the window frame is located is completely consistent with the rim surface; the axial projection of the window frame is a trapezoidal outline with a honeycomb skeleton in the internal area; the central axis of the window frame is coaxial with the generatrix of the lower edge of the rim, and the window frame surface is equipped with a connecting shaft that is consistent with the circumference of the lower edge in a direction perpendicular to the generatrix of the lower edge of the rim. The connecting shafts are arc-shaped or straight-line, multiple in number and parallel to each other; tightly arranged lightweight fan blades are passed through the connecting shafts. The fan blades are feather-shaped or leaf-shaped, and the length of the fan blades is greater than the distance between adjacent connecting shafts in the direction of the generatrix. One end of each fan blade has a ring hole that can be strung together by the connecting shaft. Adjacent fan blades are arranged in a shoulder-pressed manner from top to bottom according to the rotation direction of the rotating cover layer. The entire internal area of ​​the window is filled with upper and lower adjacent connected fan blades arranged in a stacked manner with the upper outside and the lower inside. When the rotating cover layer rotates through the circuit and is driven by electric, electromagnetic or mechanical transmission, the centrifugal and cyclonic effects inside the rotating cover layer make the stacked fan blades, which are first upper and then lower, tightly closed at the bottom peripheral hole of the edge, like a curtain covering the outside of the membrane at the bottom peripheral hole of the edge, to a certain extent hindering the gas inside the rotating cover layer from passing through the membrane at the bottom peripheral hole. When the rotating cover layer is stationary, the area between the rotating cover layer and the outer cover layer causes the fan blades to be lifted around the axis under the constraint of the connecting shaft at their end ring holes under negative pressure conditions, and the outside of the membrane at the bottom peripheral hole of the edge is like a curtain being pulled open, and the gas inside the rotating cover layer will pass through the membrane at the bottom peripheral hole, through the area between the rotating cover layer and the outer cover layer, and flow to the outer hole of the outer cover layer.

[0015] The main body of the outer cover layer is a truncated cone-shaped component, which consists of a cover body, an upper outer ring rail, a lower outer ring rail and a valve C. The center hole on the bottom surface of the cover body is integrally connected with an outlet pipe connecting section. The outer cover layer, the outlet pipe connecting section and the inlet pipe section are coaxial. The cover body of the outer row cover layer is composed of a top surface, side surfaces, a bottom surface and an outer row opening; the top surface is a toroidal surface, the inner diameter of the toroidal surface is integrally connected with the outer diameter of the large mouth end of the inverted bowl body of the three-layer enrichment and separation section complex, and an upper outer ring rail is integrally formed at the connection point and on the inner side of the toroidal surface. The upper inner ring rail of the rotating cover layer serves as the rail core and rotates in the rail tooth mouth of the upper outer ring rail; the bottom surface is a toroidal surface, the inner diameter of the toroid is smaller than the inner diameter of the upper and lower ring rails of the movable partition of the three-layer enrichment and separation section complex and is consistent with the size of the internal thread ring mouth of the exhaust pipe connection section. The toroidal surface is integrally connected with the lower outer ring rail that is assembled with the lower inner ring rail at the small mouth end of the lower edge surface of the rotating cover layer. The lower outer ring rail is coaxial with the upper outer ring rail, and the lower inner ring rail of the rotating cover layer serves as the rail core of the lower outer ring rail of the outer row cover layer and rotates in the rail tooth mouth of the lower outer ring rail; the upper inner ring of the rotating cover layer Semi-solidified oil seals are used between the rail and the upper outer ring rail of the outer discharge cover layer, and between the lower inner ring rail of the rotating cover layer and the lower outer ring rail of the outer discharge cover layer, to prevent gas from passing through the gaps between the ring rails to a certain extent; the area enclosed by the side of the cover body is in the shape of a cone, and the height of the cone is consistent with the height of the moving partition of the three-layer enrichment and separation section complex. The ports at the small end and the large end of the side of the cover body are respectively integrated with the top and bottom outer diameters of the cover body of the outer discharge cover layer; one or more outer discharge orifices are distributed on the top of the side, and the orifices are covered with a selective permeable membrane that allows non-methane component gases to pass through; through external equipment, the outer discharge orifices create negative pressure conditions for the area between the rotating cover layer and the outer discharge cover layer, so that the gas in the area between the rotating cover layer and the moving fault is more conducive to being sucked through the selective permeable membrane outside the bottom circumferential hole and discharged through the membrane-covered outer discharge orifice of the outer discharge cover layer. The outlet pipe connecting section is in the shape of a ring column and consists of two parts: a ring platform A and an internal threaded ring mouth. The ring platform A is a circular ring with a certain thickness. The inner diameter of the ring matches the inner diameter of the ring on the bottom surface of the cover body of the outer cover layer and the outer diameter of the core tube of the outlet pipe section of the device unit. A valve C is installed at the inner mouth of the ring to open or close the channel between the enclosed area generated by the movable partition of the three-layer enrichment and separation section and the outlet pipe section. One end face of the ring platform A is coaxial with the bottom surface of the cover body of the outer cover layer and is integrally formed and connected, and the other end face is integrally formed and connected with the end face of the internal threaded ring mouth. The internal threaded ring mouth is a hollow pipe section with a threaded inner wall. The outer diameter of the ring of the outlet pipe connecting section ring platform A is consistent with the outer diameter of the hollow pipe section of the internal threaded ring mouth.

[0016] The above-mentioned outlet pipe section is plug-shaped and consists of a ring platform B and a core pipe. The core pipe is a hollow pipe section, the outer diameter of which matches the inner diameter of the ring platform A of the outlet pipe connection section of the rotating cover layer. The length of the pipe section is equal to the sum of the thickness of the ring platform A of the outlet pipe connection section of the rotating cover layer and the thickness of the ring platform B with external threads of the outlet pipe section. The outer wall of the hollow pipe section of the core pipe is integrally formed and connected with the inner wall of the annular body of the ring platform B with external threads of the outlet pipe section. The outer surface of the annular body of the ring platform B with external threads of the outlet pipe section is processed with external threads, and the screwing length of the external threads of the annular body is greater than the screwing length of the internal thread ring of the outlet pipe connection section, that is, a part of the external thread of the ring platform B of the outlet pipe section is used for threaded connection with the internal thread ring of the outlet pipe connection section of the outer cover layer of the three-layer enrichment and separation section, and the other part is used for threaded connection with other device unit components.

[0017] The present invention is a device unit for preliminarily enriching and separating methane component gas and non-methane component gas in low-concentration methane coalbed methane, which is composed of an air inlet pipe section, an air outlet pipe section, and a three-layer enrichment and separation section composed of a composite body, a rotating cover layer, and an external exhaust cover layer. The device unit takes advantage of the large density difference between methane and non-methane component gases in coalbed methane, and uses the rotating cover layer to enable the mixed gas to achieve preliminarily enrichment of methane gas in the central axis area of ​​the rotating body in the formed three-dimensional gas vortex, while the non-methane component gas is preliminarily enriched in the periphery of the methane gas and separated through a selective permeable membrane; a folded sheet enclosure is formed in the central axis area of ​​the rotating body by means of a mobile partition, and the enriched methane gas is isolated to a certain extent in the internal area of ​​the mobile fault enclosure, and is sucked and stored through other external device components connected to the air outlet pipe section; the enriched non-methane component gas is separated by a membrane in the mobile partition. The system creates negative pressure in the area between the trap formed by the fault and the rotating cover layer, and in the area between the rotating cover layer and the external cover layer. This causes the stacked fan blades of the sash windows at the bottom of the two areas, located inside the mobile fault trap and between the trap formed by the mobile partition and the rotating cover layer, to be lifted. This causes the non-methane component gas to flow from the inside to the outside through the selective permeable membrane at the bottom circumferential orifice of the rotating cover layer to the area between the rotating cover layer and the external cover layer. Finally, it is sucked out and discharged through other external device components connected to the external orifice of the external cover layer membrane, thereby further enriching and separating the low-concentration methane gas in the coalbed methane. The unit structure of this device is simple and does not require chemical treatment. As one of the processing units in a complex processing flow, it is easy to assemble and put into practical use, and has great prospects for technical promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the device unit structure.

[0019] Figure 2 It is a schematic diagram of the intake pipe section structure.

[0020] Figure 3It is a schematic diagram of the complex structure of the three-layer enrichment and separation section.

[0021] Figure 4 It is a schematic diagram of the rotating cover layer structure of the three-layer enrichment and separation section.

[0022] Figure 5 They are schematic diagrams of the feather fan window structure with the fan blades at the edge of the rotating cover layer raised and closed.

[0023] Figure 6 This is a schematic diagram of the outer cover layer structure of the three-layer enrichment and separation section.

[0024] Figure 7 It is a schematic diagram of the structure of the exhaust pipe section.

[0025] Figure 8 It is a schematic diagram of the unit structure of the device in a closed state formed by a movable partition.

[0026] Figure 9 Schematic diagrams of the device unit structure of the air intake pipe section and the three-layer enrichment and separation section in the unlocked and locked states respectively.

[0027] Figure 10 Schematic diagrams of the lower buckle and upper buckle structures in the unlocked and locked states respectively.

[0028] Figure 11 Schematic diagrams of the three-layer enrichment and separation section, namely the methane enrichment zone, the non-methane component enrichment and release zone, and the non-methane component discharge zone.

[0029] In the figure: 1. Inlet pipe section, 2. Composite body, 3. Rotating cover layer, 4. Outlet cover layer, 5. Outlet pipe section, 11. Lower buckle, 12. Inlet pipe, 21. Valve A, 22. Upper buckle, 23. Inverted bowl body, 24. Connecting line, 25. Movable partition, 31. Gradually expanding surface, 32. Bevel, 33. Lower inner ring rail, 34. Upper inner ring rail, 35. Rib, 36. Feather fan window, 37. Bottom peripheral hole, 41. Cover body, 42. Outlet pipe connecting section, 43. Lower outer ring rail, 44. Upper outer ring rail, 45. Valve B, 51. Ring platform B, 52. Core pipe, 111. Lower buckle lock ring, 112. Lower buckle lock surface, 221. Upper buckle lock ring, 222. Upper buckle lock surface, 231. Neck, 232. Cone, 233. Upper limit, 234. Lower limit, 251. Lower rail core, 252. Lower ring rail, 253. Upper ring rail, 254. Upper rail core, 255. Vertical pole, 256. Folding piece, 257. Magnetic seal, 258. Extension tube, 321. Upper edge surface, 322. Lower edge surface, 361. Window frame, 362. Connecting shaft, 363. Fan blade, 411. Top surface, 412. Side surface, 413. Bottom surface, 414. Valve C, 415. External discharge orifice, 421. Ring platform A, 422. Internal threaded ring, I. Internal area of ​​movable partition enclosure, II. Area between movable partition enclosure and rotating cover layer, III. Area between rotating cover layer and external discharge cover layer. DETAILED DESCRIPTION

[0030] In one embodiment of the present invention, the intake pipe section comprises an intake pipe section and a lower retaining ring. The intake pipe section is a flexible and pressure-elastic pipe band, with ports at both ends of the pipe band respectively embedded with a cylindrical ring and a circular ring. The port of the embedded circular ring is located on the side of the small end face of the lower retaining ring locking surface, and the port of the embedded cylindrical ring is threaded on the outer wall of the cylindrical ring cylindrical surface, for connection to other pipe sections with matching pipe diameters and internal threads. The lower retaining ring locking ring is a cylindrical ring with threads on the inner wall of the cylindrical surface of the cylindrical ring. The lower retaining ring locking surface is a gradually expanding arc surface or an inclined plane circular ring. The inner diameter of the locking surface circular ring is consistent with the inner diameter of the locking ring cylindrical ring, and the outer diameter of the locking surface circular ring is larger than the locking ring cylindrical ring. The large end face of the lower retaining ring locking surface of the intake pipe section has its inner circumference integrally molded and connected to one end of the lower retaining ring locking ring cylindrical ring. The port of the embedded circular ring is located on the side of the small end face of the lower retaining ring locking surface and is integrally molded and connected to the inner circumference of the lower retaining ring locking surface circular ring.

[0031] The three-layer enrichment and separation section complex in this embodiment of the present invention consists of an upper buckle, valve A, an inverted bowl, and a movable partition. The upper buckle consists of a locking ring and a locking surface; valve A is assembled inside the cylindrical ring of the upper buckle's locking ring. The valve core of valve A is empty or can be selectively loaded with a water filtration membrane or a water attachment membrane depending on the environment; the inverted bowl consists of a neck and a frustum; and the movable partition consists of a frame, a flap, a magnetic seal, and an extension tube.

[0032] In the embodiment of the present invention, the upper buckle ring lock ring of the composite body is a cylindrical ring, and the outer wall of the cylindrical surface of the cylindrical ring is processed with an external thread that matches the internal thread of the lower buckle ring lock ring of the air inlet pipe section; the inner diameter of the upper buckle ring lock ring matches the outer diameter of the port of the composite body inverted bowl of the three-layer enrichment and separation section. The upper buckle ring lock surface is a gradually expanding arc surface or an inclined plane circular ring, and the curvature of the arc surface or the slope of the inclined plane is consistent with the locking surface of the lower buckle ring of the air inlet pipe section. The inner diameter of the upper buckle ring lock surface circular ring is consistent with the inner diameter of the locking ring cylindrical ring, and the outer diameter of the locking surface circular ring is larger than the locking ring cylindrical ring, so as to ensure that during the threaded docking process between the upper buckle ring of the three-layer enrichment and separation section and the lower buckle ring of the air inlet pipe section, the locking surfaces of the upper and lower buckle rings can press the flexible circular tube of the air inlet pipe section, thereby achieving a sealed closure between the air inlet pipe section and the three-layer enrichment and separation section. One end of the upper buckle ring lock ring is integrally connected to the complex of the three-layer enrichment and separation section, and the other end is integrally connected to the upper buckle ring lock surface and the large end face of the upper buckle ring lock surface, and the inner circumference of the circular ring is integrally connected to one end of the cylindrical ring of the upper buckle ring lock ring.

[0033] The inverted bowl of the composite body of the present invention is shaped like an inverted bowl, with no covers on either the rim or bottom. The neck and conical portion of the inverted bowl are coaxial and coaxial with the air intake section. The neck is an annular cylindrical surface, with the outer diameter of the neck annular cylindrical surface consistent with the inner diameter of the upper retaining ring locking ring. The height of the neck annular cylindrical surface is greater than the height of the upper retaining ring locking ring annular cylindrical surface. The other end of the neck annular cylindrical surface is consistent with the inner diameter of the small end of the conical portion of the inverted cone of the composite body. The conical portion is a truncated cone sidewall, with the small end of the conical portion facing the neck and the large end facing the movable partition. The gradually expanding sidewalls of the conical portion ensure sufficient diffusion of gas within the three-layer region of the three-layer enrichment and separation section body as it enters the inverted bowl through the air intake section and the neck of the composite body. One end of the neck annular cylindrical surface is integrally connected to the inner sidewall of the upper retaining ring locking ring annular cylindrical surface, while the other end is consistent with the inner diameter of the small end of the conical portion of the inverted cone of the composite body and is integrally connected to the end of the conical portion.

[0034] The movable partition of the composite body in the embodiment of the present invention is an annular cylinder, which is composed of a frame, a folding piece, a magnetic seal and an extension tube. The frame of the movable partition is composed of an upper ring rail, a lower ring rail and a vertical pole. The upper ring rail and the lower ring rail of the frame of the movable partition are vertically opposite and coaxial with the air intake pipe section; the upper ring rail and the lower ring rail are circular ring rails of equal size, and the size of the rails is consistent with the end face of the large mouth of the cone part of the inverted bowl body, and the rail teeth of the upper ring rail and the lower ring rail are facing downward and upward respectively. The number of vertical poles of the movable partition is greater than or equal to 2, and they are cylindrical to reduce the degree of vibration of the gas vortex on the frame. The connection point between the vertical pole and the ring rail divides the circumference of the ring rail equally. The folding piece of the movable partition is a corrugated profile or other folding profile. The folding bones in the folding piece are made of rigid material. Several parallel folding bones are embedded in the folding piece, and the folding bones are perpendicular to the pulling direction of the folding piece; the two ends of the rigid folding bone are each equipped with a rigid rail core. The shape of the rail core is not restricted, but under the control of an external control device, the rail core can make synchronous and smooth movements in the same direction in the track teeth of the upper and lower ring rails. The number of upper and lower rail cores is the same as the number of folding bones. A semi-solidified oil seal is used between the rail core and the ring rail to prevent gas from passing through the gap between the rail core and the ring rail to a certain extent; when the folding piece is in the maximum expanded state, its length is at least sufficient to meet the arc length between two adjacent vertical poles on the side wall of the annular cylindrical surface formed by the operation along the ring rail. The expansion tubes of the mobile partition are hollow tubes with no restrictions on cross-sectional shape. The number of expansion tubes matches the number of vertical poles, and all expansion tubes must be made of the same material and dimensions. Inside the expansion tubes, wiring, concentration monitors, and electrode plates are installed according to the needs of the device unit. Unless otherwise specified, expansion tubes are only installed with wiring, and the interior of the expansion tubes can be left empty. The backs of the track teeth of the upper and lower ring rails of the mobile partition frame are integrally connected to the end faces of the large opening of the cone portion of the inverted bowl and the large opening of the outer cover layer of the three-layer enrichment and separation section, respectively. The two ends of the vertical poles of the mobile partition are perpendicularly connected to the upper and lower ring rails, respectively. One end of the mobile partition's folding flap is integrally connected to the side wall of the vertical pole, while the other end is equipped with a magnetic seal that is the same length and parallel to the folding flap. When the folding flap is in its fully retracted state, the mobile partition has a cage-like shape; when the folding flap is in its fully extended state, the mobile partition has a water bottle-like shape.

[0035] The rotating cover layer of the three-layer enrichment and separation section in this embodiment of the present invention consists of a gradually expanding surface, a lip, ribs, an upper inner ring rail, a lower inner ring rail, and a sash window. It is cap-shaped, with a gradually expanding bottom circumference and coaxial with the intake pipe section. The gradually expanding surface of the rotating cover layer is truncated cone-shaped, and the upper inner ring rail at the small end of the cone is a hollow or solid annular ring that mates with the upper outer ring rail of the outer exhaust cover layer of the three-layer enrichment and separation section. The vertical projections of the upper and lower edges of the rotating cover layer are both circular; the upper and lower edges of the edge are both circular arc surfaces or inclined planes, which are gradually expanding and gradually contracting respectively; the small end of the upper edge of the edge is consistent in size with the large end of the gradually expanding surface; the main line formed by the intersection of the plane where the center axis of the edge is located and the upper and lower edges is a broken line, and the broken line angle formed when pointing inward toward the center of the edge is less than 180 degrees; the intersection line between the upper and lower edges of the edge is circular, and the maximum size of the edge still maintains a certain spatial area with the inner wall of the outer cover layer of the three-layer enrichment and separation section; the bottom circumferential holes on the lower edge of the edge are circular, and there are multiple numbers, and the holes are covered with a selective permeable membrane that allows non-methane component gases to pass through; the lower inner ring rail is a hollow or solid annular body, which cooperates with the lower outer ring rail on the bottom surface of the outer cover layer of the three-layer enrichment and separation section. The feather fan window of the rotating cover layer is composed of window frames, connecting shafts and fan blades; the outer frame of the window frame's axial projection is trapezoidal and the interior is honeycomb-shaped, the surface where the window frame is located is completely consistent with the edge surface, and the central axis of the window frame is coaxial with the generatrix of the lower edge surface of the edge; the connecting shafts of the feather fan window are arc-shaped or straight-line, and there are multiple and parallel to each other; the lightweight fan blades of the feather fan window are feather-shaped or leaf-shaped, and the length of the fan blades is greater than the distance between adjacent connecting shafts in the direction of the generatrix, and one end of each fan blade has a ring hole that can be strung together by the connecting shaft. The outer diameter of the port at the small end of the gradually expanding surface of the rotating cover layer is integrally formed and connected to the upper inner ring rail. The inner wall of the gradually expanding surface is integrally formed with spiral ribs. When the gradually expanding surface rotates around the axis, the space area inside the gradually expanding surface will generate a three-dimensional gas vortex. The large port on the upper edge of the rotating cover layer is consistent in size with the large port on the lower edge and is integrally formed and connected. The small end of the upper edge of the edge is consistent in size with the large end of the gradually expanding surface and is integrally formed and connected. The port at the small end of the lower edge of the edge is integrally formed and connected to the lower inner ring rail. The lower inner ring rail is a hollow or solid annular body that cooperates with the bottom outer ring rail in the outer discharge cover layer of the three-layer enrichment and separation section. The rotational motions of the upper inner ring rail of the gradually expanding surface of the rotating cover layer and the lower inner ring rail of the edge have the same direction and magnitude of angular velocity.

[0036] The outer discharge cover layer of the three-layer enrichment and separation section in the embodiment of the present invention consists of a cover body, an upper outer ring rail, a lower outer ring rail, and valve B. It is truncated cone-shaped and coaxial with the inlet pipe section. The cover body of the outer discharge cover layer consists of a top surface, side surfaces, a bottom surface, and an outer discharge opening. The top surface of the cover body is a circular ring surface, and the inner opening of the ring is equipped with an upper outer ring rail that matches the upper inner ring rail of the rotating cover layer. The bottom surface of the cover body is a circular ring surface, the inner diameter of the ring is consistent with the size of the internal thread ring opening of the outlet pipe connection section and is coaxial with it. The lower outer ring rail is equipped with a lower outer ring rail that matches the lower inner ring rail of the rotating cover layer. The area enclosed by the side of the cover body is truncated cone-shaped, and the height of the cone is consistent with the height of the movable partition of the three-layer enrichment and separation section complex. One or more outer discharge openings are distributed at the top of the side surface, and the openings are covered with a selective permeable membrane that allows non-methane components to pass through. The outlet pipe connection section of the outer discharge cover layer is annular and cylindrical, consisting of a ring platform A and an internal thread ring opening. Ring platform A is a circular ring with a certain thickness. The inner diameter of the ring matches the inner diameter of the ring on the bottom surface of the outer cover layer and the outer diameter of the core tube of the outlet pipe section of the device unit; the internal thread ring is a hollow pipe section with a threaded inner wall. The outer diameter of the ring of the outlet pipe connecting section ring platform A is consistent with the outer diameter of the hollow pipe section with the internal thread ring. The inner diameter of the circular ring on the top surface of the outer cover layer is integrally formed and connected to the outer diameter of the large end of the bowl body of the three-layer enrichment and separation section complex, and the inner side of this connection is integrally formed and connected to the outer ring rail on the outer cover layer; the height of the truncated cone formed by the side surface of the outer cover layer is consistent with the height of the movable partition of the three-layer enrichment and separation section complex, and the ports at the small end and large end of the side surface are respectively integrally formed and connected to the outer ring openings of the circular top and bottom surfaces of the outer cover layer; one end face of the ring platform A of the outer cover layer gas outlet pipe connection section is coaxial and integrally formed with the bottom surface of the outer cover layer, and the other end face is integrally formed and connected to the end face of the internal thread ring opening. Semi-solidified oil seals are used between the outer ring rail on the outer cover layer and the upper inner ring rail on the rotating cover layer, and between the lower outer ring rail on the outer cover layer and the lower inner ring rail on the rotating cover layer, to a certain extent preventing gas from passing through the gaps between the ring rails.

[0037] In this embodiment of the present invention, the outlet pipe section is a plug-shaped body coaxial with the inlet pipe section, consisting of a ring platform B and a core pipe. The core pipe of the outlet pipe section is a hollow pipe section, the outer diameter of which matches the inner diameter of the ring platform A of the outlet pipe connection section of the rotating cover layer. The length of the pipe section is equal to the sum of the thickness of the ring platform A of the outlet pipe connection section of the rotating cover layer and the thickness of the ring platform B of the outlet pipe section with external threads. The outer wall of the hollow pipe section of the outlet pipe section core pipe is partially integrally connected to the inner wall of the ring platform A of the outlet pipe connection section of the rotating cover layer, and the other part is integrally connected to the inner wall of the ring body of the externally threaded ring platform B of the outlet pipe section. The outer part of the annular body of the ring platform B with external threads in the outlet pipe section is processed with threads, and the thread engagement length is greater than the thread engagement length of the internal thread ring opening of the outlet pipe connecting section, that is, a part of the external thread of the ring platform B of the outlet pipe section is used for threaded connection with the internal thread ring opening of the outlet pipe connecting section of the outer discharge cover layer of the three-layer enrichment and separation section, and the other part is used for threaded connection with other device unit components.

[0038] Embodiments of the present invention:

[0039] A schematic diagram of the unit structure of a device for preliminary enrichment and separation of low-concentration methane from coalbed methane is shown in the figure. Figure 1 As shown; the schematic diagram of the structure of the air inlet pipe section of the device unit component, the complex of the three-layer enrichment and separation section, the rotating cover layer of the three-layer enrichment and separation section, the outer cover layer of the three-layer enrichment and separation section and the air outlet pipe section are shown respectively. Figure 2 、 Figure 3 、 Figure 4 、 Figure 6 and Figure 7 As shown; the schematic diagram of the feather window structure with the fan blades at the edge of the rotating cover layer raised and closed is as shown Figure 5 As shown; the schematic diagram of the device unit structure in the closed state formed by the movable partition is as follows Figure 8 As shown; the schematic diagram of the device unit structure of the air intake section and the three-layer enrichment and separation section in the unlocked and locked states is shown as follows Figure 9 As shown; the schematic diagram of the lower buckle and upper buckle in the unlocked and locked states is shown in Figure 10 As shown; the schematic diagram of the methane enrichment zone, non-methane component enrichment and release zone, and non-methane component discharge zone of the three-layer enrichment and separation section is shown in Figure 11 shown.

[0040] The present invention discloses a device unit structure for preliminary enrichment and separation of low-concentration methane from coalbed methane. The main components of the unit structure are, from the inlet end to the outlet end, an air inlet pipe section (1), a three-layer enrichment and separation section, and an air outlet pipe section (5). The unit structure of the three-layer enrichment and separation section is composed of, from the inside to the outside, a complex body (2) consisting of an inverted bowl body (23) and a movable partition (25), a rotating cover layer (3) with a gradually expanding bottom circumference, and an external discharge cover layer (4). The three-layer structure divides the device unit into, from the inside to the outside, an internal area (I) of the movable partition enclosure, an area (II) between the movable partition enclosure and the rotating cover layer, and an area (III) between the rotating cover layer and the external discharge cover layer, respectively, for achieving the enrichment of methane, the enrichment and release of non-methane components, and the external discharge of non-methane components.

[0041] According to the composition structure of each component of the device unit structure involved in the direction of gas streamline, the components of the air inlet pipe section (1) are the air inlet pipe section (12) and the lower buckle (11); the components of the complex body (2) of the three-layer enrichment and separation section are the upper buckle (22), valve A (21), the inverted bowl body (23), and the movable partition (25); the components of the rotating cover layer (3) of the three-layer enrichment and separation section are the gradually expanding surface (31) with ribs (35) formed on the inner wall, the bottom peripheral hole (37) covered with a selective permeable membrane, and the edge (32) with a fan window (36) outside the hole. The outer cover layer (4) of the three-layer enrichment and separation section involves two flow branches. The components of one branch are the bottom surface (413) of the cover body (41) of the outer cover layer (4), the outer discharge opening (415) with a film on the side wall and the cover body (41) of the valve C (414), and the top surface (411). The components of the other branch are the outlet pipe connecting section (42) composed of the ring platform A (421) and the internal thread ring (422), and the valve B (45). The components of the outlet pipe section (5) are the core pipe (52) and the ring platform B (51) with external threads.

[0042] The assembly connection method of each component of the device unit structure includes: the lower buckle ring lock surface (112) of the lower buckle ring (11) is connected to the lower buckle ring lock ring (111) by integrated molding; the inner ring mouth of the lower buckle ring lock surface (112) is connected to the port of the intake pipe section (12) by integrated molding; the upper buckle ring lock surface (222) is connected to the upper buckle ring lock ring (221) by integrated molding; the neck (231) of the inverted bowl body (23) is connected to the small end of the cone part (232) by integrated molding; the large end of the cone part (232) of the inverted bowl body (23) is connected to the back side of the track tooth of the frame upper rail ring constituting the movable partition (25) by integrated molding; the track teeth of the frame upper rail ring and the lower rail ring of the movable partition (25) are opposite and the track teeth are opposite. The two tracks are parallel, and the vertical distance between the two tracks is connected by an integrated molding of a vertical rod (255); the folding bone at one end of the movable partition (25) folding piece (256) is connected to the side wall of the vertical rod (255) of the movable partition (25), and the folding bone at the other end is connected to the magnetic seal (257); the bottom side of the vertical rod (255) of the movable partition (25) is connected to the side wall of the extension tube (258) by an integrated molding; the back side of the track tooth of the lower track ring of the movable partition (25) frame is connected to the bottom surface (413) of the outer cover layer (4) by an integrated molding; the two ends of the embedded folding bone of the movable partition (25) folding piece (256) are respectively integrated with the upper track core (254) and the lower track core (251) by an integrated molding. The rotating cover layer (3) is connected by forming a large opening end of the upper edge surface (321) of the edge (32) and a large opening end of the lower edge surface (322) of the edge (32); the rotating cover layer (3) is connected by forming a large opening end of the gradually expanding surface (31) and a small opening end of the upper edge surface (321) of the edge (32); the rotating cover layer (3) is connected by forming a small opening end of the gradually expanding surface (31) and a small opening end of the lower edge surface (322) of the edge (32) respectively with the upper inner ring rail (34) and the lower inner ring rail (33); the inner side wall of the gradually expanding surface (31) of the rotating cover layer (3) is connected by forming a spiral rib (35); the outer ring outer opening of the top surface (411) of the cover body (41) of the outer cover layer (4) is connected by forming a small opening of the upper inner ring rail (34) and the lower inner ring rail (33); 12) The small port is integrally molded and connected; the large port on the side (412) of the cover body (41) of the outer cover layer (4) is integrally molded and connected to the outer ring port on the bottom surface (413); at the connection line (24) between the inverted bowl body (23) and the movable partition (25) of the composite body (2), the inner ring port of the top surface (411) of the outer cover layer (4) is integrally molded and connected to the outer side wall of the composite body (2); the bottom surface (413) of the outer cover layer (4) is integrally molded and connected to the end face of the ring platform A (421) of the outer cover layer (4) outlet pipe connection section (42); the outer ring port of the ring platform A (421) of the outer cover layer (4) outlet pipe connection section (42) is integrally molded and connected to the port of the inner thread ring (422);The connecting line (24) between the inverted bowl body (23) and the movable partition (25) of the composite body (2) and the top surface (411) of the outer cover layer (4) are connected to the inner side of the cover body (41) at the intersection of the connecting line (24) between the inverted bowl body (23) and the movable partition (25) and the top surface (411) of the outer cover layer (4), the outer cover layer (4) upper outer ring rail (44) and the top surface (411) of the cover body (41) are integrally formed and connected; the outer cover layer (4) lower outer ring rail (43) and the bottom surface (413) of the cover body (41) are integrally formed and connected; the window frame (361) of the rotating cover layer (3) and the connecting shaft (362) are integrally formed and connected; the outer side wall of the core tube (52) of the air outlet pipe section (5) and the inner side wall of the annular body of the ring platform B (51) of the air outlet pipe section (5) are integrally formed and connected.

[0043] The lower buckle (11) of the air intake pipe section (1) is assembled on the neck (231) area of ​​the inverted bowl body (23) of the three-layer enrichment and separation section complex (2); the valve A (21) is assembled with the inner ring of the ring of the lock surface (112) of the lower buckle of the air intake pipe section (1); the lower buckle (11) of the air intake pipe section (1) is threadedly assembled with the upper buckle (22) of the three-layer enrichment and separation section complex (2); the upper rail core (254) and the lower rail core (251) of the folded bone end of the movable partition (25) folded piece (256) are respectively assembled with the upper ring rail (253) and the lower rail ring of the movable partition (25) for track assembly; the magnetic seal strip (257) at the end of the movable partition (25) folded piece (256) is magnetically assembled with the adjacent movable partition (25) vertical rod (255); the upper inner ring rail (34) and the lower inner ring rail (35) of the rotating cover layer (3) are assembled with the upper inner ring rail (34) and the lower inner ring rail (35) of the rotating cover layer (3) for track assembly. The inner ring track (33) is respectively assembled with the upper inner ring track (34) and the lower inner ring track (33) of the outer cover layer (4); the feather fan window (36) connecting shaft (362) of the rotating cover layer (3) is assembled with the fan blade (363); the bottom peripheral hole (37) of the edge (32) of the rotating cover layer (3) is assembled with the selective permeation membrane that allows non-methane component gas to pass through; the valve B (45) is assembled with the inner ring opening of the ring platform A (421) of the outlet pipe connecting section (42) of the outer cover layer (4); the outer discharge hole (414) of the outer cover layer (4) cover body (41) is assembled with the selective permeation membrane that allows non-methane component gas to pass through; the ring platform B (51) of the outlet pipe section (5) is threadedly assembled with the inner thread ring opening (422) of the outlet pipe connecting section (42) of the outer cover layer (4).

[0044] The lower buckle (11) of the air intake pipe section (1) moves up and down in the neck (231) of the inverted bowl body (23) of the composite body (2), with the upper limit (233) being the connection line between the lower buckle lock surface (112) and the lower buckle lock ring (111), and the lower limit (234) being the connection line between the neck (231) of the inverted bowl body (23) and the cone portion (232). The lower buckle (11) of the air intake pipe section (1) is threadedly connected to the upper buckle (22) of the three-layer enrichment and separation section composite body (2), and the upper buckle lock surface (222) and the lower buckle lock surface (112) enable the flexible circular tube of the air intake pipe section (1) to be compressed between the lock surfaces, thereby achieving a sealed closure between the air intake pipe section (1) and the three-layer enrichment and separation section. The low-concentration methane coalbed methane gas transmission component is respectively threadedly connected to the inlet pipe section (12) port of the inlet pipe section (1) and the ring platform B (51) of the outlet pipe section (5) in the device unit, so as to keep the axial direction of the device unit vertical. The device unit is normally operated by external power, core control, monitoring components and line system. Before the device unit is started, the folding piece (256) of the movable partition (25) of the three-layer enrichment and separation section complex (2) is in the maximum retracted state. At this time, the movable partition (25) is combined with the inverted bowl body (23) and the upper buckle (22) to form a water bottle body. The internal area (I) of the movable partition enclosure of the three-layer enrichment and separation section and the area (II) between the movable partition enclosure and the rotating cover layer are in a connected state.

[0045] When the device unit is started, the external control device opens valve A (21) and closes valve B (45) at the same time. Low-concentration methane coalbed methane passes through the air inlet pipe section (1) of the air inlet pipe section (1), the upper buckle (22) of the composite body (2), valve A (21), the inverted bowl body (23), and the movable partition (25) in sequence, and enters the connecting area of ​​the inner area (I) of the movable partition enclosure of the three-layer enrichment and separation section and the area (II) between the movable partition enclosure and the rotating cover layer, and is trapped inside the connecting area by the rotating cover layer (3). The gradually expanding side wall of the cone portion (232) of the inverted bowl body (23) of the composite body (2) is conducive to the full diffusion of the gas after it enters the three-layer area of ​​the main body of the three-layer enrichment and separation section through the air inlet pipe section (1) and the neck (231) of the inverted bowl body (23) of the composite body (2). When the external monitoring component uses the intake air flow rate or the gas pressure inside the connected area as a monitoring indicator to meet the operation requirements, the valve A (21) is closed and the rotation operation of the rotating cover layer (3) is started; the upper inner ring track (34) and the lower inner ring track (33) of the rotating cover layer (3) serve as the track cores of the upper outer ring track (44) and the lower outer ring track (43) of the outer cover layer (4), respectively, and are driven by electric power, electromagnetic or mechanical transmission to make coaxial and angular velocity motion to drive the rotating cover layer (3) to rotate at a controlled speed inside the device unit, and the rotating cover layer (3) gradually expands the surface ( The inner wall of the mobile partition trap is integrally formed with spiral ribs (35), which is conducive to the generation of a three-dimensional gas vortex in the space region inside the gradually expanding surface (31); in the communicating region (I) inside the mobile partition trap and the region (II) between the mobile partition trap and the rotating cover layer, methane and non-methane component gases with a large density difference in the coalbed methane are regularly distributed in the three-dimensional gas vortex. Under the installation condition that the small end of the cone surrounded by the gradually expanding surface (31) of the rotating cover layer (3) is at the top and the large end is at the bottom, the methane gas with a smaller density is concentrated in the rotating cover layer ( 3) The entire inner central axis position and moves toward the small end of the cone body surrounded by the gradually expanding surface (31), and the non-methane component gas with a larger density is concentrated in the outer area of ​​the inner central axis position of the rotating cover layer (3) and moves toward the large end of the cone body surrounded by the gradually expanding surface (31); the upper edge surface (321) and the lower edge surface (322) of the rotating cover layer (3) along the mouth (32) of the gradually expanding and gradually contracting rotating cover layer (3) intersect with the plane where the central axis of the mouth (32) is located to form a generatrix fold line, and the fold line angle formed in the direction inward toward the center of the mouth (32) is small. At 180 degrees, that is, the edge (32) follows the gradually expanding surface (31), and the gradually expanding degree of the rotating cover layer (3) is first increased through the upper edge surface (321) of the edge (32), and then the bottom edge is closed inward through the lower edge surface (322) of the edge (32). This shape promotes the non-methane component gas with higher density in the coalbed methane to be enriched in the inner area near the wall of the bottom edge (32) in a three-dimensional vortex state, just like a safe harbor area that can avoid the non-methane component gas from being disturbed again to a certain extent and destroying its concentrated state.At this time, the external control device starts the complex (2) moving partition (25) folding piece (256) to perform the operation of unfolding; the upper rail core (254) and the lower rail core (251) of the folding piece (256) of the moving partition (25) respectively perform synchronous rotation in the same direction in the track teeth of the upper and lower ring rails (252) of the moving partition (25), that is, no matter whether the rail core is driven by electric power, electromagnetic or mechanical transmission, during the process of the rail core rotating along the ring rail, the rail core drives the folding piece to unfold through the folding bone and approaches the adjacent vertical rod (255) in the direction of movement until the folding piece is folded. The magnetic seal strip (257) at the end of the sheet contacts the vertical rod (255) and is locked by magnetically controlled adsorption to ensure that a closure is formed between two adjacent vertical rods (255); a semi-solidified oil seal is used between the track core and the ring track to prevent gas from passing through the gap between the track core and the ring track to a certain extent; when the folding sheet (256) is fully expanded, the folding sheet (256) and the vertical rod transform the annular column frame of the movable partition (25) into an annular column with a side wall in a closed state, and at this time, the movable partition (25) is combined with the inverted bowl body (23) and the upper buckle (22) to form a water bottle body. When the methane concentration monitoring component of the mobile partition (25) pipe enhancer connected to the complex (2) monitors that the methane concentration value reaches the requirement or meets the conventional setting requirements according to the coalbed methane composition and speed control rotation index, the formation of the mobile partition (25) water bottle body, that is, the internal area (I) of the mobile partition enclosure, the area (II) between the mobile partition enclosure and the rotating cover layer, are respectively used as signs of the formation of the methane enrichment area and the non-methane component enrichment and release area, and the external control device will simultaneously control two branches respectively. One branch is to open the valve B (45) and the operation of the external suction system connected to the gas outlet pipe section (5) ring platform B (51), so as to realize that the methane gas enriched in the internal area (I) of the mobile partition enclosure passes through the valve The door B (45) passes through the ring platform A (421) of the outlet pipe connecting section (42) of the outer exhaust cover layer (4), the core tube (52) of the outlet pipe section (5), and the ring platform B (51) of the outlet pipe section (5) in sequence, and enters into the other external device unit that is threadedly connected to the ring platform B (51), thereby realizing the separation of the enriched methane and the non-methane component enriched gas; the other branch is that the external control device will open the external suction system operation that is connected to the membrane outer exhaust port (414) located on the upper part of the side (412) of the cover body (41) of the outer exhaust cover layer (4), so as to realize that the enriched non-methane component gas in the area (II) between the mobile partition enclosure and the rotating cover layer is discharged to the outside of the device unit through the area (III) between the rotating cover layer and the outer exhaust cover layer.Since a semi-solidified oil seal is used between the upper inner ring rail (34) of the rotating cover layer (3) and the upper outer ring rail (44) of the outer cover layer (4), and between the lower inner ring rail (33) of the rotating cover layer (3) and the lower outer ring rail (43) of the outer cover layer (4), gas is prevented from passing through the gap between the ring rails to a certain extent. Therefore, during the gas discharge process of this branch, the bottom peripheral hole (37) of the lower edge surface (322) of the edge (32) of the rotating cover layer (3) is the non-methane component enriched gas. The body enters the main channel from the area (II) between the movable partition enclosure and the rotating cover layer to the area (III) between the rotating cover layer and the outer cover layer; when the external control device starts the suction operation of the area (III) between the rotating cover layer and the outer cover layer, the negative pressure principle makes the intersection position between the upper edge surface (321) and the lower edge surface (322) of the edge (32) of the rotating cover layer (3) as a protrusion inside the area (III) between the rotating cover layer and the outer cover layer. The gas flowing from the bottom peripheral hole (37) to the discharge port (414) forms a cyclone around the bottom peripheral hole (37). Under the action of the cyclone, the light feather-shaped or leaf-shaped fan blades (363) of the feather fan window (36) outside the bottom peripheral hole (37) along the lower edge surface (322) of the opening (32) are transformed from the shoulder pressing mode of the adjacent fan blades (363) and the overlapping mode of the upper and lower layer connecting shafts (362) to the mode of the fan blades (363) being lifted around the connecting shaft (362). At this time, the outside of the selective permeable membrane at the bottom peripheral hole (37) of the lower edge surface (322) of the bead (32) is like a curtain being pulled open, and the non-methane component gas inside the rotating cover layer (3) will pass through the selective permeable membrane at the bottom peripheral hole (37), enter the area (III) between the rotating cover layer and the external exhaust cover layer from the area (II) between the movable partition trap and the rotating cover layer, and be discharged to the outside of the device unit through the selective permeable membrane at the external exhaust hole (414) of the external exhaust cover layer (4). At this point, an operation cycle is completed, the two branches stop the gas suction operation, valve B is closed, and all device unit components return to the initial state. Opening valve A again will be the beginning of a new operation. Repeating the above, the periodic operation of this device unit can achieve the initial enrichment of low-concentration methane in coalbed methane and the initial separation of non-methane component gases.

Claims

1. A device unit structure for preliminary enrichment and separation of low-concentration methane in coalbed methane, comprising an air inlet pipe section, an air outlet pipe section, and a three-layer enrichment and separation section composed of a composite body, a rotating cover layer, and an external exhaust cover layer. The device unit is characterized by: From the inlet end to the outlet end, there are the air inlet pipe section, the three-layer enrichment and separation section and the air outlet pipe section in sequence; the air inlet pipe section is composed of the air inlet pipe section and the lower buckle ring, the complex of the three-layer enrichment and separation section is composed of the upper buckle ring, valve A, the inverted bowl body and the movable partition, the lower buckle ring of the air inlet pipe section is threadedly assembled with the upper buckle ring of the three-layer enrichment and separation section complex; the rotating cover layer of the three-layer enrichment and separation section is composed of a gradually expanding surface, a rim, ribs, an upper inner ring rail, a lower inner ring rail and a feather fan window, the outer cover layer of the three-layer enrichment and separation section is composed of a cover body, an upper outer ring rail, a lower outer ring rail and valve B, and the air outlet pipe section is composed of a ring platform B and a core pipe; the unit structure of the three-layer enrichment and separation section is composed of a complex composed of an upper buckle ring, valve A, an inverted bowl body and a movable partition, a gradually expanding bottom circumference closing The three-layer structure of the rotating cover layer and the outer cover layer divides the device unit from the inside to the outside into the inner area of ​​the mobile partition enclosure, the area between the mobile partition enclosure and the rotating cover layer, and the area between the rotating cover layer and the outer cover layer, which are used to achieve the enrichment of low-concentration methane gas, the enrichment and release of non-methane components, and the discharge of non-methane components respectively; among the various components of the device unit structure, the lower buckle ring locking surface of the lower buckle ring is integrally formed and connected with the lower buckle ring locking ring, and the inner ring mouth of the lower buckle ring locking surface is integrally formed and connected with the air intake pipe section port; the upper buckle ring locking surface of the upper buckle ring is integrally formed and connected with the upper buckle ring locking ring; the neck of the inverted bowl body is integrally formed and connected with the small mouth end of the cone part; the large mouth end of the cone part of the inverted bowl body is integrally formed and connected with the track tooth of the upper rail ring constituting the mobile partition frame The back side is connected by integrated molding; the track teeth of the upper and lower track rings of the movable partition frame are opposite and the tracks are parallel, and the vertical distance between the two tracks is connected by an integrated molding of the vertical pole; the movable partition folding piece, the folding bone at one end is connected by an integrated molding to the side wall of the vertical pole of the movable partition, and the folding bone at the other end is connected by an integrated molding to the magnetic seal strip; the side of the bottom of the vertical pole of the movable partition is connected by an integrated molding to the side wall of the extension tube; the back side of the track teeth of the lower track ring of the movable partition frame is connected by an integrated molding to the bottom surface of the outer cover layer; the two ends of the folding bone embedded in the movable partition folding piece are respectively connected by an integrated molding to the upper track core and the lower track core; the large end of the upper edge of the rotating cover layer is connected by an integrated molding to the large end of the lower edge of the edge; the large end of the gradually expanding surface of the rotating cover layer and the upper edge of the edge are connected by an integrated molding to the large end of the lower edge of the edge The small mouth end of the surface is integrally formed and connected; the small mouth end of the rotating cover layer's gradually expanding surface and the small mouth end of the lower edge surface of the edge are respectively integrally formed and connected with the upper inner ring rail and the lower inner ring rail; the inner side wall of the rotating cover layer's gradually expanding surface is integrally formed and connected with the spiral ribs; the circular outer opening of the top surface of the outer cover layer's cover body is integrally formed and connected with the small port on the side; the large port on the side of the outer cover layer's cover body is integrally formed and connected with the circular outer opening of the bottom surface; at the connecting line between the inverted bowl body and the movable partition of the composite body, the circular inner opening of the top surface of the outer cover layer is integrally formed and connected with the outer side wall of the composite body; the bottom surface of the outer cover layer is integrally formed and connected with the end face of the ring platform A of the outer cover layer's air outlet pipe connection section; the circular outer opening of the ring platform A of the outer cover layer's air outlet pipe connection section is integrally formed and connected with the internal threaded ring opening port;The inner side of the cover body where the connection line between the inverted bowl body and the movable partition of the complex intersects with the top surface of the cover body of the outer cover layer, the back side of the upper outer ring track tooth of the outer cover layer is integrated with the top surface of the cover body; the back side of the lower outer ring track tooth of the outer cover layer is integrated with the bottom surface of the cover body; the feather fan window frame of the rotating cover layer is integrated with the connecting shaft; the outer side wall of the core pipe of the outlet pipe section is integrated with the inner side wall of the torus of the ring platform B of the outlet pipe section; after the coalbed methane containing low concentration of methane enters the device from the intake pipe section of the intake pipe section, it passes through the upper buckle of the complex of the three-layer enrichment and separation section in turn. , valve A, inverted bowl body and movable partition. The rotating cover layer in the three-layer enrichment and separation section is controlled by the external control component to rotate at a controlled speed according to the composition of the incoming gas and the requirements of enrichment and separation. The ribs on the inner wall of the gradually expanding surface of the rotating cover layer are used to make the gas generate a three-dimensional gas vortex inside the cover body of the rotating cover layer. Based on the density difference between the various components of the coalbed methane, methane is in the central axis area of ​​rotation under the gas vortex, while the non-methane components in the coalbed methane will be on the periphery of the central axis area. When the fold is fully unfolded, the movable partition appears as a water bottle body. The inside of its enclosed area is the methane enrichment area, and the outside of the enclosed area is the gradually expanding area. The area between the rotating cover layers with gradually expanding mouths is the non-methane component enrichment and release area; there are two flow branches in the external discharge cover layer of the three-layer enrichment and separation section. The components of one branch are the bottom surface of the cover body of the external discharge cover layer, the cover body with the membrane-covered external discharge orifice on the side wall, and the top surface of the cover body, that is, a three-dimensional gas vortex is generated inside the cover body of the rotating cover layer. The gas in the non-methane component enrichment and release area outside the central axis area will sink and pass through the selective permeable membrane at the peripheral holes along the bottom of the mouth of the gradually expanding rotating cover layer. When the fan structure is unfolded, it is released to the suction and discharge area and is released through the space between the external discharge cover layer and the gradually expanding bottom The outlet on the upper sidewall of the suction and discharge area between the peripheral rotating cover layers is drawn to the exterior of the device unit structure. Another branch line consists of a gas outlet pipe connection section, consisting of a ring platform A and an internally threaded ring opening, and valve B. The gas outlet pipe section consists of a core pipe and a ring platform B with external threads. A three-dimensional gas vortex is generated within the rotating cover layer. Methane gas is enriched in the rotating central axis area and enters the gas outlet pipe section of the device unit structure through the enclosed area formed by the fully expanded movable partition. This achieves preliminary enrichment and separation of low-concentration methane from the coalbed methane.

2. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 1 is characterized by: The inverted bowl body is in the shape of an inverted bowl; both ends of the bowl mouth and the bottom of the inverted bowl body have no covers, and are composed of a neck and a frustum part, the neck and the frustum part are coaxial, and are both coaxial with the air intake pipe section; the neck is a cylindrical surface, and the outer diameter of the neck cylindrical surface is consistent with the inner diameter of the upper buckle ring lock ring; the column height of the neck cylindrical surface is greater than the column height of the upper buckle ring lock ring cylindrical surface, and one port of the neck cylindrical surface is integrally formed and connected with the inner side wall of the upper buckle ring lock ring cylindrical surface; the other port of the neck cylindrical surface is consistent with the inner diameter of the small mouth end of the frustum part of the inverted cone of the complex body, and is integrally formed and connected with the port of the small mouth end of the frustum part; at both ends of the neck Before the end faces are integrally connected with the upstream and downstream components, the lower buckle of the air inlet pipe section is sleeved on the outer periphery of the neck, so that the lower buckle of the air inlet pipe section can move up and down in the neck of the bowl body, the upper limit of which is the connection line between the locking surface and the locking ring of the lower buckle, and the lower limit is the connection line between the neck of the bowl body and the frustum; the frustum is the side wall of a truncated cone, the small end of the frustum faces the neck side, and the large end faces the movable partition, and the gradually expanding side wall of the frustum ensures that when the gas enters the three-layer area of ​​the three-layer enrichment and separation section main body through the neck of the air inlet pipe section and the composite bowl body, it can be fully diffused in the area.

3. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 1 is characterized by: The movable partition is composed of a ring-shaped columnar frame, a folding piece, a magnetic seal and an extension tube; the ring-shaped columnar frame is composed of an upper ring rail, a lower ring rail and a vertical pole; the upper ring rail and the lower ring rail are vertically opposite to each other and coaxial with the air intake pipe section; the upper ring rail and the lower ring rail are circular ring rails of equal size, and the size of the rails is consistent with the end face of the large mouth of the cone part of the inverted bowl body, and the track teeth of the upper ring rail and the lower ring rail are oriented downward and upward respectively, and the back of the track teeth are integrally formed and connected with the end face of the large mouth of the cone part of the inverted bowl body and the end face of the large mouth of the outer cover layer of the three-layer enrichment and separation section respectively; in the vertical direction, the upper ring rail and the lower ring rail are supported and connected by the vertical pole, that is The two ends of the vertical poles are respectively connected vertically to the upper circle rail and the lower circle rail, the number of vertical poles is greater than or equal to 2, and the connection points between the vertical poles and the circle rails divide the circumference of the circle rails equally; the vertical poles are cylindrical to reduce the vibration degree of the gas vortex on the frame; in terms of vertical height, the height of the vertical poles matches the height of the folding pieces that are integrally connected to them and can form movable partitions, that is, the folding pieces start from the vertical poles and slide along the circle rails to expand and retract; the number of folding pieces of the movable partitions is consistent with the number of vertical poles, that is, a folding piece can be stretched out from the side of each vertical pole to move in a circle along the circle rail; the folding pieces are corrugated profiles or other folding profiles, and the folding bones in the folding pieces are rigid materials The material is made of a material, and several parallel folding bones are embedded in the folding piece, and the folding bones are perpendicular to the pulling direction of the folding piece; the two ends of the rigid folding bone are each equipped with a rigid rail core, and the shape of the rail core is not limited, but under the control of the external control device, the rail core is required to make synchronous and smooth movement in the same direction in the track teeth of the upper and lower ring rails. During the movement, the folding bones of the folding piece are always parallel to the vertical rods of the movable partition; a semi-solidified oil seal is used between the rail core and the ring rail to prevent gas from passing through the gap between the rail core and the ring rail to a certain extent; the length of the folding piece in the maximum expanded state is at least enough to meet the space between two adjacent vertical rods on the side wall of the annular cylinder formed by the operation of the ring rail The arc length, that is, when all the folding pieces are maximally expanded, the folding pieces and the columns will transform the cylindrical frame of the mobile partition into a cylindrical frame with the side wall in a closed state. At this time, the mobile partition, the inverted bowl body, and the upper buckle are combined into a water bottle body, and the folding pieces in the maximally retracted state will make the mobile partition, the inverted bowl body, and the upper buckle be combined into a cage-shaped body; the end of the other end of the folding piece that is not integrally connected to the vertical rod is equipped with a magnetic seal strip that is the same length as the folded bone and parallel to the folded bone. When the folding piece is unfolded along the ring track from the vertical rod integrally connected thereto and contacts the adjacent vertical rod, the magnetic seal strip and the adjacent vertical rod are magnetically attracted to ensure that the two adjacent vertical rods are closed; The expansion tube is a hollow tube. The cross-sectional shape of the tube is not restricted. The number of expansion tubes is consistent with the number of vertical poles. The material and size specifications of all expansion tubes must be the same. The expansion tubes are parallel to the vertical poles and are integrally connected and fixed to the lower part of the vertical poles and distributed inside the closed body formed by the movable partition. According to the needs of the device unit, the interior of the expansion tube is assembled with circuits, concentration monitors, and electrode plates. If there are no special requirements, the interior of the expansion tube is only assembled with circuits, and the interior of the expansion tube is allowed to be empty.

4. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 1 is characterized by: The rotating cover layer is in the shape of a cap, with a gradually expanding bottom circumference, and is composed of a gradually expanding surface, an edge, ribs, an upper inner ring rail, a lower inner ring rail, and a feather fan window. The rotating cover layer is coaxial with the air intake pipe section; the gradually expanding surface of the rotating cover layer is a side wall surface of a truncated cone, and the outer diameter of the small mouth end of the truncated cone surrounded by the gradually expanding surface is integrally formed and connected to the upper inner ring rail. The upper inner ring rail is a hollow or solid annular body, and is driven by electric, electromagnetic or mechanical transmission to cooperate with the upper outer ring rail in the outer discharge cover layer of the three-layer enrichment and separation section. The inner wall of the gradually expanding surface is integrally formed with spiral ribs; the edge of the rotating cover layer is located at the brim of the cap-shaped rotating cover layer, and along The mouth is composed of an upper edge surface and a lower edge surface. The upper and lower edge surfaces of the mouth are gradually expanding and gradually contracting respectively. The upper and lower edge surfaces are both circular arc surfaces or inclined planes and their vertical projections are both circular. The large port of the upper edge surface of the mouth is consistent in size with the large port of the lower edge surface and is integrally formed and connected. The small end of the upper edge surface of the mouth is consistent in size with the large end of the gradually expanding surface and is integrally formed and connected. The generatrix formed by the intersection of the plane where the center axis of the mouth is located and the upper and lower edge surfaces is a broken line. The broken line angle formed when pointing inward toward the center of the mouth is less than 180 degrees. The intersection line between the upper and lower edge surfaces of the mouth is circular, and the outer diameter of the circle is less than The inner diameter of the intersection line of the circle formed by the plane where the circle is located and the outer cover layer of the three-layer enrichment and separation section; the circular holes of the same specifications are evenly distributed along the circumference of the lower edge surface of the rim, that is, the bottom circumferential holes, and there are multiple holes. The hole openings are covered with a membrane, which is a selective permeable membrane. The non-methane component gas in the area between the partition trap and the rotating cover layer is transmitted to the area between the rotating cover layer and the outer cover layer through the membrane. The methane gas blocked by the membrane will be rotated again when the mobile fault fold is in a closed state to increase the probability of it existing as methane enriched gas in the internal area of ​​the mobile partition trap; the small end port of the lower edge surface of the rim is integrally formed and connected to the lower The inner ring rail and the lower inner ring rail are hollow or solid circular ring bodies, which are driven by electric, electromagnetic or mechanical transmission and cooperate with the lower outer ring rail on the bottom surface of the outer cover layer of the three-layer enrichment and separation section. The lower inner ring rail serves as the rail core of the lower outer ring rail on the bottom surface of the outer cover layer, and rotates in the rail tooth mouth of the lower outer ring rail. The small end surface of the lower edge of the edge is the bottom surface of the rotating cover layer, and the bottom surface is actually the bottom surface of the outer cover layer. The rotational motion of the upper inner ring rail of the gradually expanding surface of the rotating cover layer and the lower inner ring rail of the edge has the same direction and the same magnitude of angular velocity. At the bottom peripheral hole of the lower edge of the edge, a feather fan window is integrated on the outer wall surface of the edge.

5. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 4 is characterized by: The feather fan window is composed of a window frame, a connecting shaft and fan blades; the surface where the window frame is located is completely consistent with the edge surface, the axial projection of the window frame is a trapezoidal outer contour, and the internal area has a honeycomb skeleton shape; the central axis of the window frame is coaxial with the generatrix of the lower edge surface of the edge, and the window frame surface is equipped with a connecting shaft that is consistent with the circumference of the lower edge in a direction perpendicular to the generatrix of the lower edge surface of the edge. The connecting shafts are arc-shaped or straight-line, multiple in number and parallel to each other; tightly arranged lightweight fan blades are passed through the connecting shafts, and the fan blades are feather-shaped or leaf-shaped. The length of the fan blades is greater than the distance between adjacent connecting shafts in the direction of the generatrix. One end of each fan blade has a ring hole that can be strung together by the connecting shaft. Adjacent fan blades are arranged in a shoulder-pressed manner from top to bottom according to the rotation direction of the rotating cover layer. The fan blades cover the entire internal area of ​​the window, up and down The adjacent connected fan blades are arranged in an upper outer and lower inner stacking manner. When the rotating cover layer is driven by electric, electromagnetic or mechanical transmission through the circuit to rotate, the centrifugal and cyclonic effects inside the rotating cover layer make the stacked fan blades, which are first upper and then lower, tightly closed at the bottom peripheral hole of the edge, like a curtain covering the outside of the membrane at the bottom peripheral hole of the edge, to a certain extent hindering the gas inside the rotating cover layer from passing through the membrane at the bottom peripheral hole. When the rotating cover layer is stationary, the area between the rotating cover layer and the outer cover layer is under negative pressure conditions, so that the fan blades are lifted around the axis under the constraint of the connecting shaft at their end ring holes, and the outside of the membrane at the bottom peripheral hole of the edge is like a curtain being pulled open. The gas inside the rotating cover layer will pass through the membrane at the bottom peripheral hole, through the area between the rotating cover layer and the outer cover layer, and flow to the outer hole of the outer cover layer.

6. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 1 is characterized by: The outer row cover layer body is in the shape of a truncated cone, and is composed of a cover body, an upper outer ring rail, a lower outer ring rail and a valve B. The center hole on the bottom surface of the cover body is integrally connected with an air outlet pipe connection section. The outer row cover layer, the air outlet pipe connection section and the air inlet pipe section are coaxial. The cover body of the outer row cover layer is composed of a top surface, a side surface, a bottom surface and an outer row opening; the top surface is a toroidal surface, and the inner diameter of the toroidal surface is integrally formed and connected with the outer diameter of the large mouth end of the inverted bowl body of the three-layer enrichment and separation section complex, and is located on the inner side of the toroidal surface. The upper outer ring rail is integrally formed at the connection point, and the upper inner ring rail of the rotating cover layer serves as the rail core and rotates in the rail tooth mouth of the upper outer ring rail; the bottom surface is a toroidal surface, and the inner diameter of the torus is smaller than the outer diameter of the three-layer enrichment and separation section complex. The inner diameters of the upper and lower ring rails of the movable partition are consistent with the size of the internal thread ring opening of the exhaust pipe connection section. The lower outer ring rail is integrally formed and connected on the annular surface. The lower outer ring rail is assembled with the lower inner ring rail at the small end of the lower edge of the rotating cover layer. The lower outer ring rail and the upper outer ring rail are coaxial. The lower inner ring rail of the rotating cover layer serves as the rail core of the lower outer ring rail of the outer cover layer and rotates in the rail tooth mouth of the lower outer ring rail. Semi-solidified oil seals are used between the upper inner ring rail of the rotating cover layer and the upper outer ring rail of the outer cover layer, and between the lower inner ring rail of the rotating cover layer and the lower outer ring rail of the outer cover layer, to avoid gas passing through the gap between the ring rails to a certain extent. The area enclosed by the side of the cover body is frustum-shaped. The height of the truncated cone is consistent with the height of the movable partition of the three-layer enrichment and separation section complex. The ports at the small end and the large end of the side of the cover body are respectively connected to the outer diameter of the top and bottom surfaces of the outer cover layer through an integrated molding; one or more outer discharge orifices are distributed on the top of the side of the cover body, and the orifices are covered with a selective permeable membrane that allows non-methane component gases to pass through; the outer discharge orifices create negative pressure conditions for the area between the rotating cover layer and the outer discharge cover layer through external equipment, so that the gas in the closed area formed by the rotating cover layer and the mobile fault is more conducive to passing through the selective permeable membrane outside the bottom hole and being discharged through the outer discharge orifice of the membrane located in the outer discharge cover layer by suction; the outlet pipe connection section is annular and cylindrical, and is formed by the ring platform A It consists of two parts: annular ring and an internal threaded ring mouth. Ring platform A is a circular ring with a certain thickness. The inner diameter of the ring matches the inner diameter of the ring on the bottom surface of the outer cover layer and the outer diameter of the core tube of the outlet pipe section of the device unit. A valve B is installed at the inner mouth of the ring to open or close the channel between the enclosed area formed by the movable partition of the three-layer enrichment and separation section and the outlet pipe section. One end face of the annular ring of ring platform A is coaxial with the bottom surface of the outer cover layer and is integrally connected, and the other end face is integrally connected with the end face of the internal threaded ring mouth. The internal threaded ring mouth is a hollow pipe section with a threaded inner wall. The outer diameter of the ring of ring platform A in the outlet pipe connecting section is consistent with the outer diameter of the hollow pipe section of the internal threaded ring mouth.

7. The unit structure of the device for preliminary enrichment and separation of low-concentration methane from coalbed methane according to claim 1 is characterized by: The outlet pipe section is plug-shaped and consists of a ring platform B and a core tube; the core tube is a hollow pipe section, the outer diameter of the pipe section matches the inner diameter of the circular ring of the ring platform A of the rotating cover layer outlet pipe connecting section, and the length of the pipe section is equal to the sum of the thickness of the circular ring of the ring platform A of the rotating cover layer outlet pipe connecting section and the thickness of the circular ring of the ring platform B with external threads of the outlet pipe section; the outer wall of the hollow pipe section of the core tube is integrally formed and connected with the inner wall of the circular body of the ring platform B with external threads of the outlet pipe section; the outside of the circular body of the ring platform B of the outlet pipe section is processed with an external thread, and the thread engagement length is greater than the thread engagement length of the internal thread ring of the outlet pipe connecting section, that is, a part of the external thread of the ring platform B of the outlet pipe section is used for threaded connection with the internal thread ring of the outlet pipe connecting section of the outer cover layer of the three-layer enrichment and separation section, and the other part is used for threaded connection with other device unit components.

Images