Device and method for extracting humic acid from lignite

Abstract

The invention discloses a device and method for extracting humic acid from lignite, which belongs to the technical field of humic acid extraction and separation. The device comprises: a support, a fixed cylinder is horizontally fixed at the middle part of which an inner turntable is rotatably connected to the fixed cylinder; partitions are circumferentially fixedly distributed on the inner turntable; a feeding seat is installed on one side of the upper end face of the support, an extension plate is extended on the support in the inner diameter direction, and a material port is provided on the extension plate; a plurality of filtration units are circumferentially distributed, each filtration unit is installed on the inner turntable and is located between two partitions, and a filter cloth is connected to the outer surface of the filtration unit; a leaching pipe is vertically installed on one side of the support; a frame is vertically connected to the support, a sliding seat is horizontally slidably installed on the frame, and a rinsing pipe is fixed on the sliding seat; in the invention, multiple filtration units can all rotate with the inner turntable to the rinsing operation area and the leaching operation area, so as to facilitate different types of operation processing at the same time and improve the extraction efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of humic acid extraction and separation, and in particular relates to a device and method for extracting humic acid from lignite. Background Art

[0002] Humic acids are complex organic compounds primarily derived from the decomposition of plant and animal residues. They are widely present in natural environments such as soil, peat, and lignite. Currently, humic acids are typically extracted from raw materials through chemical or physical methods to form extracts. Commonly used extractants include alkaline solutions (such as sodium hydroxide, sodium carbonate), acidic solutions (such as hydrochloric acid, sulfuric acid) and aqueous solvents. In the prior art, for example, the invention patent with publication number CN117861301B uses an extraction device that can provide negative pressure under the filter cloth through a negative pressure mechanism to filter the humic acid extraction solution, thereby achieving an efficient solid-liquid separation effect with minimal scratching of the filter cloth. However, during the extraction of humic acid, the corrugated filter cloth used easily causes filter residue to accumulate between the corrugated gaps, affecting the filtration effect. At the same time, the magnetic shaking mechanism used has a poor effect on the tensioning and shaking of the filter cloth, and the filter residue easily detaches directly from the surface of the filter cloth. At the same time, the shaking performance of the filter residue is weak, and the vibration filtration effect of the filter residue cannot be achieved. Therefore, it is necessary to provide a device and method for extracting humic acid from lignite to solve the problems raised in the above-mentioned background technology. Summary of the Invention

[0003] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a device for extracting humic acid from lignite, comprising: a support, a fixed cylinder is fixed horizontally at the middle part, an inner turntable is rotatably connected to the fixed cylinder; partitions are fixedly distributed on the inner turntable in a circle; a feeding seat is installed on one side of the upper end face of the support, an extension plate is extended in the inner diameter direction on the support, the feeding seat is fixed on the upper end face of the extension plate, and a material port is provided on the extension plate; a plurality of filtration units are distributed in a circle, each of the filtration units is installed in the inner turntable. The filtration unit is located on the turntable and between the two partitions. A filter cloth is connected to the outer cover of the filtration unit; a rinsing pipe is vertically installed on one side of the support, one end of the rinsing pipe extends to the top of the inner turntable, and a spray pipe is installed on the rinsing pipe; a frame is vertically connected to the support, a sliding seat is horizontally slidably installed on the frame, a rinsing pipe is fixed on the sliding seat, and a plurality of nozzles are distributed below the rinsing pipe; a drive motor is fixed in the fixed cylinder, and the output end of the drive motor is connected to the inner turntable through gear meshing.

[0004] Preferably, the filtration unit includes: two tensioning rollers arranged correspondingly, both of which are horizontally rotatable and connected to the inner turntable, and the filter cloth is sleeved on the two tensioning rollers; a plurality of filtration tubes arranged in an arc shape and located between the two tensioning rollers; a side guard edge fixed on the side wall of the partition, and the side guard edge is distributed parallel to the tensioning roller.

[0005] Preferably, a shaft sleeve is fixed in the middle of the inner turntable, and a sleeve is rotatably connected to the center of the inner upper end of the shaft sleeve. A connecting shaft is coaxially fixed in the sleeve, and a first bevel gear is sleeved on the connecting shaft; one end of the tensioning roller is rotatably connected to the side wall of the shaft sleeve through a bearing, and a first bevel gear is fixed at its end, and the first bevel gear is meshed with the first bevel gear; a swing motor is installed outside the shaft sleeve, and the output end of the swing motor is connected to the sleeve.

[0006] Preferably, a plurality of guide cavities are provided on the side wall of the inner turntable, and each of the suction filter tubes is sealed and connected to the guide cavity respectively; a negative pressure bin is provided on the side wall of the fixed cylinder, an annular opening is provided below the negative pressure bin, and air flow holes are provided above the guide cavity, and the air flow holes are connected to the negative pressure bin through the annular opening; a pumping pump is connected to the outside of the negative pressure bin.

[0007] Preferably, the distribution gap between the side guard and the tensioning roller is no more than 0.9 mm.

[0008] Preferably, the suction tube is configured as a conical structure, and a plurality of through holes are distributed on the suction tube; a rotating tube is provided at one end of the suction tube, a valve sleeve is fixed on the rotating tube, the suction tube is rotatably connected to the valve sleeve, the end of the suction tube is located in the valve sleeve and is provided with an inner spring, one end of the inner spring is connected to the valve sleeve; a toothed disk is fixed outside the valve sleeve, and a top pressure plate is fixed on the suction tube, and the top pressure plate is in contact with the toothed disk.

[0009] Preferably, the lower end of the shaft sleeve of the inner turntable is rotatably connected to a transmission shaft, and a second helical gear is sleeved on the transmission shaft. One end of the suction tube is rotatably connected to the side wall of the shaft sleeve through a bearing, and a second bevel gear is fixed to the end thereof, and the second bevel gear is meshed with the second bevel gear.

[0010] A built-in motor is fixed below the inner turntable, and an output end of the built-in motor is connected to the transmission shaft.

[0011] Preferably, a plurality of balls are embedded on the top pressure plate, and each of the balls rolls and contacts the surface of the toothed plate; a support baffle is fixed outside the valve sleeve, and the support baffle is sealingly sleeved below the suction tube.

[0012] Preferably, the distribution density of the through holes at the tip of the suction tube is greater than the distribution density of the through holes at the other end; a filter outlet is provided below each of the suction units in the inner turntable, and an external outlet is provided in the middle of the lower end surface of the fixed cylinder.

[0013] Preferably, a method for extracting humic acid from lignite comprises the following steps:

[0014] Step 1: The fine powder that has been initially crushed and screened is mixed with a pre-prepared dilute acid solution for solid-liquid mixing, and stirred with a magnetic stirrer for 4 hours to allow for sufficient reaction and dissolution to form a humic acid extract; the inner turntable rotates at a low speed under the control of a drive motor, and the humic acid extract is evenly spread on the filter cloth of each filtration unit through a feeding base;

[0015] Step 2: The negative pressure chamber on the fixed cylinder provides negative pressure extraction power to the suction tube through each diversion cavity. At this time, each suction tube performs preliminary filtration of the extract on the filter cloth; the swing motor drives the tensioning rollers to rotate back and forth in the positive and negative directions, so that the filter cloth is synchronously transmitted and moved; at the same time, the built-in motor drives the suction tubes to rotate through the transmission shaft. The top pressure plate on the suction tube can generate periodic impact force in the rotational contact with the rubbing tooth plate, causing the suction tube to vibrate accordingly, and a part of the filter residue falls to the tip of the suction tube by inertia, and is then discharged through the filter outlet on the inner turntable;

[0016] Step 3: After the initial filtration, the filter residue rotates with the inner turntable to the elution pipe, which rinses the filter residue through the spray pipe to remove the mother liquor remaining on the surface of the filter residue. Then the inner turntable rotates to the rinse pipe, and the filter residue on the filter cloth is rinsed through the nozzles.

[0017] Step 4: Repeat steps 2 and 3, increasing the suction intensity of the filtration pipe until the residual solvent and insoluble impurities on the surface of the filter residue are completely removed;

[0018] Step 5: Collect the filter residue through the outlet below the fixed cylinder and then dry and freeze it.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] In the present invention, multiple filtration units are distributed circumferentially in the inner turntable, and each filtration unit can rotate with the inner turntable to the rinsing operation area and the leaching operation area, so that different types of treatments can be performed on multiple filtration units at the same time, thereby improving the extraction efficiency and shortening the time of the entire process;

[0021] The suction filtration unit mainly used in the present invention can stretch and expand the filter cloth through the tensioning roller, and the multiple suction filtration tubes arranged under the filter cloth can perform filtration operations at the same time. The filter cloth can be displaced slightly during the reciprocating rotation of the tensioning roller, which has a strong material shaking effect and avoids the filter residue from accumulating in the same position for a long time; and the suction filtration tube can be driven to rotate by the transmission shaft through the meshing action of the bevel gear so that the top pressure plate at its end is in rotational contact with the rubbing tooth plate, thereby generating periodic impact force, further improving the material shaking effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 It is a top view of the fixed cylinder in the present invention;

[0024] Figure 3 Schematic diagram of the structure of the rinsing pipe and the nozzle in the present invention;

[0025] Figure 4 It is a cross-sectional schematic diagram of the present invention;

[0026] Figure 5 Schematic diagram of the distribution structure of the suction filtration tube in the present invention;

[0027] Figure 6 Schematic diagram of the installation structure of the tensioning roller in the present invention;

[0028] Figure 7 Schematic diagram of the installation structure of the suction filter tube in the present invention;

[0029] Figure 8 for Figure 7 A schematic diagram of the structure at center A;

[0030] Figure 9 Schematic diagram of the structure of the suction filtration tube in the present invention;

[0031] Figure 10 It is a partial structural cross-sectional view of the suction filtration tube in the present invention;

[0032] Figure 11 for Figure 10 A magnified schematic diagram of the structure at point B in the middle;

[0033] In the figure: 1. Support; 11. Fixed cylinder; 12. Feeding seat; 13. Feeding port; 14. Rinse pipe; 15. Spray pipe; 16. Frame; 17. Sliding seat; 18. Rinse pipe; 19. Spray head; 110. Negative pressure chamber; 111. External outlet; 2. Inner turntable; 21. Partition plate; 22. Filter cloth; 23. Driving motor; 24. Shaft sleeve; 25. Casing; 26. Connecting shaft; 27. Guide cavity; 28, air flow hole; 29, transmission shaft; 210, second bevel gear; 211, built-in motor; 212, filter outlet; 3, filtration unit; 31, tensioning roller; 32, side guard; 33, first bevel gear; 4, filtration tube; 41, through hole; 42, rotating tube; 43, valve sleeve; 44, inner spring; 45, rubbing gear plate; 46, top pressure plate; 47, support plate; 48, limit ring. DETAILED DESCRIPTION

[0034] See also Figures 1-11 In an embodiment of the present invention, a device for extracting humic acid from lignite comprises:

[0035] The support 1 has a fixed cylinder 11 fixed horizontally in the middle thereof, and the inner turntable 2 is rotatably connected to the fixed cylinder 11;

[0036] Partitions 21 are fixedly distributed on the inner turntable 2. The partitions 21 can divide the surface of the inner turntable 2 into multiple independent workstation areas.

[0037] A feeding seat 12 is mounted on one side of the upper end surface of the support 1. An extension plate is provided on the support 1 in the inner diameter direction. The feeding seat 12 is fixed to the upper end surface of the extension plate. A material port 13 is provided on the extension plate, so that the feeding seat 12 spreads the humic acid extract evenly on the inner turntable 2 through the material port 13.

[0038] There are multiple filtration units 3 distributed around the circumference. Each filtration unit 3 is installed on the inner turntable 2 and located between two partitions 21. The outer surface of each filtration unit 3 is connected with a filter cloth 22.

[0039] A rinsing pipe 14 is vertically mounted on one side of the support 1, with one end of the rinsing pipe 14 extending above the inner turntable 2. A spray pipe 15 is mounted on the rinsing pipe 14, which can rinse the leachate on the surface of the filter cloth 22, thereby removing soluble impurities and residual mother liquor attached to the surface of the filter residue;

[0040] A frame 16 is vertically connected to the support 1. A sliding seat 17 is mounted on the frame 16 for horizontal sliding movement. A screw structure is provided within the frame 16, and the sliding seat 17 is threadedly connected to the screw in the screw structure, so that the sliding seat 17 can slide horizontally along the frame 16 during the forward and reverse rotation of the screw. A rinsing pipe 18 is fixed to the sliding seat 17, and a plurality of nozzles 19 are distributed below the rinsing pipe 18. The rinsing pipe 18 is mainly used to further clean the filter residue in the leachate, removing the solvent and a small amount of insoluble impurities remaining in the filter residue. Pure water or distilled water is usually used for rinsing to ensure the purity of the filter residue. The rinsing pipe 18 is directly connected to an external water source (such as a clean water tank, tap water, or a circulating water system) via a hose or pipe. The water pump provides pressure to ensure that the nozzles 19 have sufficient spraying force.

[0041] The driving motor 23 is fixed in the fixing cylinder 11 , and the output end of the driving motor 23 is connected to the inner turntable 2 through gear meshing.

[0042] In this embodiment, the filtration unit 3 includes:

[0043] There are two tensioning rollers 31 provided correspondingly, both of which are horizontally rotatably connected to the inner turntable 2, and the filter cloth 22 is sleeved on the two tensioning rollers 31;

[0044] Multiple suction pipes 4 are arranged in an arc shape and located between two tensioning rollers 31. The angle between the two tensioning rollers 31 is 65 degrees, and the expanded surface of the filter cloth 22 is a fan-shaped structure. The tensioning rollers 31 can fully tension the filter cloth 22 so that the surface of the filter cloth 22 is concave near the center of the fan-shaped circle.

[0045] The side guard 32 is fixed on the side wall of the partition 21. The side guard 32 is distributed parallel to the tensioning roller 31. The side guard 32 is mainly used to block the filter residue on the surface of the filter cloth 22 to the left and right to prevent the filter residue from falling off from the side of the filter cloth 22, so that the filter residue rolls off along the surface of the filter cloth 22 toward the center of the circle.

[0046] As a preferred embodiment, a shaft sleeve 24 is fixed in the middle of the inner turntable 2, and a sleeve 25 is rotatably connected to the center of the inner upper end of the shaft sleeve 24. A connecting shaft 26 is coaxially fixed in the sleeve 25, and a first bevel gear is sleeved on the connecting shaft 26;

[0047] One end of the tensioning roller 31 is rotatably connected to the side wall of the shaft sleeve 24 through a bearing, and a first bevel gear 33 is fixed to the end thereof, and the first helical gear is meshed with the first bevel gear 33;

[0048] A swing motor (not shown in the figure) is installed outside the shaft sleeve 24. The output end of the swing motor is connected to the sleeve 25. The swing motor can control the shaft sleeve 24 to rotate back and forth under continuous forward and reverse drive, so that each tensioning roller 31 can rotate synchronously to tension and swing the filter cloth 22, so as to achieve a certain material shaking effect.

[0049] In this embodiment, a plurality of guide cavities 27 are provided on the side wall of the inner turntable 2, and each of the suction filter tubes 4 is sealed and connected to the guide cavity 27 respectively; a negative pressure bin 110 is provided on the side wall of the fixed cylinder 11, and an annular opening is provided below the negative pressure bin 110, and air flow holes 28 are provided above the guide cavities 27, and the air flow holes 28 are connected to the negative pressure bin 110 through the annular opening;

[0050] The negative pressure chamber 110 is externally connected to a pumping pump (not shown in the figure), that is, the pumping pump pumps air pressure to the negative pressure chamber 110, forming a low-pressure environment in the negative pressure chamber 110. Each suction tube 4 can obtain a consistent negative pressure condition through the guide cavity 27, so that during the filtration process, the liquid permeates the filter cloth 22, while the solid filter residue is retained on the surface of the filter cloth 22, thereby realizing solid-liquid separation.

[0051] In this embodiment, the distribution gap between the side guard 32 and the tensioning roller 31 is no greater than 0.9 mm.

[0052] In this embodiment, the suction filter tube 4 is configured as a conical structure, and a plurality of through holes 41 are distributed on the suction filter tube 4; a rotating tube 42 is provided at one end of the suction filter tube 4, a valve sleeve 43 is fixed on the rotating tube 42, and the suction filter tube 4 is rotatably connected to the valve sleeve 43, and the end of the suction filter tube 4 is located in the valve sleeve 43 and is provided with an inner spring 44, one end of the inner spring 44 is connected to the valve sleeve 43, it should be noted that a limit ring 48 is fixed in the center of the valve sleeve 43 (an assembly gap is left between the limit ring 48 and the suction filter tube 4), therefore, one end of the inner spring 44 is connected to the valve sleeve 43 through the limit ring;

[0053] A toothed disc 45 is fixed to the outside of the valve sleeve 43, and a top pressure disc 46 is fixed to the suction tube 4, and the top pressure disc 46 is in contact with the toothed disc 45. The other end of the inner spring 44 is connected to the suction tube 4. Therefore, it can use the spring tension to make the top pressure disc 46 on the suction tube 4 always maintain contact with the toothed disc 45, so that when the top pressure disc 46 on the suction tube 4 can subsequently generate relative rotational motion with the toothed disc 45, the surface of the top pressure disc 46 and the teeth or protrusions of the toothed disc 45 are constantly in contact and separation, forming a mechanical excitation source to excite the suction tube 4 to generate axial fixed-frequency vibration.

[0054] As a preferred embodiment, the lower end of the shaft sleeve 24 of the inner turntable 2 is rotatably connected to a transmission shaft 29, and a second bevel gear 210 is sleeved on the transmission shaft 29. One end of the suction tube 4 is rotatably connected to the side wall of the shaft sleeve 24 through a bearing, and a second bevel gear is fixed to its end. The second bevel gear 210 meshes with the second bevel gear;

[0055] A built-in motor 211 is fixed below the inner turntable 2, and the output end of the built-in motor 211 is connected to the transmission shaft 29, so that the built-in motor 211 drives each filter tube 4 to rotate synchronously, and the filter tube 4 in the rotating motion can provide a dynamic filtration effect, so that the filter residue on the filter cloth 22 can be rolled to a certain extent, and the filter residue is accumulated on the surface.

[0056] In this embodiment, a plurality of balls are embedded in the top pressure plate 46, and each of the balls rolls in contact with the surface of the toothed plate 45; a support baffle 47 is fixed to the outside of the valve sleeve 43, and the support baffle 47 is sealingly sleeved under the suction tube 4, that is, since the surface of the top pressure plate 46 and the teeth or protrusions of the toothed plate 45 are in continuous contact and separation during the rotation process, this relative movement will generate periodic impact forces, which are transmitted to the suction tube 4 through the top pressure plate 46, causing the suction tube 4 to vibrate.

[0057] In this embodiment, the distribution density of the through holes 41 at the tip of the suction filter tube 4 is greater than the distribution density of the through holes 41 at the other end;

[0058] A filter outlet 212 is provided in the inner rotary disc 2 below each of the filtration units 3 , and an external outlet 111 is provided in the middle of the lower end surface of the fixed cylinder 11 .

[0059] A method for extracting humic acid from lignite, comprising the following steps:

[0060] Step 1: The fine powder that has been initially crushed and screened is mixed with a pre-prepared dilute acid solution for solid-liquid mixing, and stirred with a magnetic stirrer for 4 hours to allow it to fully react and dissolve, thereby forming a humic acid extract; the inner turntable 2 rotates at a low speed under the control of the drive motor 23, and the humic acid extract is evenly spread on the filter cloth 22 of each filtration unit 3 through the feeding base 12;

[0061] Step 2: The negative pressure bin 110 on the fixed cylinder 11 provides negative pressure extraction power to the suction tube 4 through each guide cavity 27. At this time, each suction tube 4 performs preliminary filtration on the extract on the filter cloth 22; the swing motor drives each tensioning roller 31 to rotate back and forth in the positive and negative directions, so that the filter cloth 22 is synchronously transmitted and moved; at the same time, the built-in motor 211 drives each suction tube 4 to rotate through the transmission shaft 29, and the top pressure plate 46 on the suction tube 4 can generate periodic impact force in the rotational contact with the rubbing tooth plate 45, so that the suction tube 4 vibrates accordingly, and a part of the filter residue falls to the tip of the suction tube 4 by inertia, and is discharged through the filter outlet 212 on the inner turntable 2, which facilitates the removal of large-particle filter residue impurities, and the filtration efficiency is improved by 60%, the filter cloth replacement cycle is extended by 40%, and the product quality is more stable;

[0062] Step 3: After the initial filtration, the filter residue rotates with the inner turntable 2 to the rinsing pipe 14. The rinsing pipe 14 rinses the filter residue through the spray pipe 15 to remove the mother liquor remaining on the surface of the filter residue. Then, the inner turntable 2 rotates to the rinsing pipe 18, and the filter residue on the filter cloth 22 is rinsed through the nozzles 19.

[0063] Step 4: Repeat steps 2 and 3, increasing the suction intensity of the suction pipe 4 until the residual solvent and insoluble impurities on the surface of the filter residue are completely removed;

[0064] Step 5: The filter residue is collected through the discharge port 111 below the fixed cylinder 11 and then dried and frozen.

[0065] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. A device for extracting humic acid from lignite, characterized in that: It includes: A support (1) has a fixed cylinder (11) fixed horizontally in the middle thereof, and an inner rotating disk (2) is rotatably connected in the fixed cylinder (11); Partitions (21) are fixedly distributed around the inner turntable (2); A feeding seat (12) is mounted on one side of the upper end surface of the support (1); an extension plate is provided on the support (1) extending in the inner diameter direction; the feeding seat (12) is fixed on the upper end surface of the extension plate; and a material port (13) is provided on the extension plate; A plurality of filtration units (3) are distributed around a circumference, each filtration unit (3) is mounted on the inner turntable (2) and located between two partitions (21), and a filter cloth (22) is connected to the outer surface of the filtration unit (3); A rinsing pipe (14) is vertically mounted on one side of the support (1), one end of the rinsing pipe (14) extends above the inner turntable (2), and a spray pipe (15) is mounted on the rinsing pipe (14); A frame (16) is vertically connected to the support (1), a sliding seat (17) is horizontally slidably mounted on the frame (16), a rinsing pipe (18) is fixed on the sliding seat (17), and a plurality of nozzles (19) are distributed below the rinsing pipe (18); A drive motor (23) is fixed in the fixed cylinder (11), and an output end of the drive motor (23) is connected to the inner rotary disc (2) for transmission through gear meshing; The filtration unit (3) comprises: Two tensioning rollers (31) are correspondingly provided, and both of the tensioning rollers (31) are horizontally rotatably connected to the inner turntable (2), and the filter cloth (22) is sleeved on the two tensioning rollers (31); A plurality of suction tubes (4) are arranged in an arc shape and located between two tensioning rollers (31); A side guard (32) is fixed on a side wall of the partition (21), and the side guard (32) is parallel to the tensioning roller (31); The suction filter tube (4) is configured as a conical cylinder structure, and a plurality of through holes (41) are distributed on the suction filter tube (4); a rotating tube (42) is provided at one end of the suction filter tube (4), a valve sleeve (43) is fixed on the rotating tube (42), the suction filter tube (4) is rotatably connected to the valve sleeve (43), the end of the suction filter tube (4) is located in the valve sleeve (43), and an inner spring (44) is provided inside the valve sleeve (43), and one end of the inner spring (44) is connected to the valve sleeve (43); A toothed disc (45) is fixed outside the valve sleeve (43), and a pressure plate (46) is fixed on the suction filter tube (4), and the pressure plate (46) is in contact with the toothed disc (45); The lower end of the shaft sleeve (24) of the inner turntable (2) is rotatably connected to a transmission shaft (29), and a second bevel gear (210) is sleeved on the transmission shaft (29). One end of the suction filter tube (4) is rotatably connected to the side wall of the shaft sleeve (24) through a bearing, and a second bevel gear is fixed to the end thereof. The second bevel gear (210) is meshed with the second bevel gear. A built-in motor (211) is fixed below the inner turntable (2), and an output end of the built-in motor (211) is connected to the transmission shaft (29).

2. The device for extracting humic acid from lignite according to claim 1, characterized in that: A shaft sleeve (24) is fixed in the middle of the inner turntable (2), a sleeve (25) is rotatably connected to the center of the inner upper end of the shaft sleeve (24), a connecting shaft (26) is coaxially fixed in the sleeve (25), and a first helical gear is sleeved on the connecting shaft (26); One end of the tensioning roller (31) is rotatably connected to the side wall of the shaft sleeve (24) via a bearing, and a first bevel gear (33) is fixed to the end thereof, and the first helical gear is meshed with the first bevel gear (33); A swing motor is installed outside the shaft sleeve (24), and the output end of the swing motor is connected to the sleeve (25).

3. The device for extracting humic acid from lignite according to claim 1, characterized in that: A plurality of guide cavities (27) are provided on the side wall of the inner turntable (2), and each of the suction filter tubes (4) is sealed and communicated with the guide cavities (27) respectively; a negative pressure bin (110) is provided on the side wall of the fixed cylinder (11), an annular opening is provided below the negative pressure bin (110), and air flow holes (28) are provided above the guide cavities (27), and the air flow holes (28) are communicated with the negative pressure bin (110) through the annular opening; The negative pressure chamber (110) is externally connected to a pumping pump.

4. The device for extracting humic acid from lignite according to claim 1, characterized in that: The distribution gap between the side guard (32) and the tensioning roller (31) is no greater than 0.9 mm.

5. The device for extracting humic acid from lignite according to claim 1, characterized in that: A plurality of balls are embedded in the top pressure plate (46), and each of the balls rolls and contacts the surface of the toothed plate (45); a support plate (47) is fixed to the outside of the valve sleeve (43), and the support plate (47) is sealingly sleeved below the suction filter tube (4).

6. The device for extracting humic acid from lignite according to claim 3, characterized in that: The distribution density of the through holes (41) at the tip of the suction filter tube (4) is greater than the distribution density of the through holes at the other end; A filter outlet (212) is provided in the inner rotary disc (2) below each of the filtration units (3), and an external outlet (111) is provided in the middle of the lower end surface of the fixed cylinder (11).

7. A method for extracting humic acid from lignite, which uses the device for extracting humic acid from lignite as claimed in claim 6, characterized in that: It includes the following steps: Step 1: The fine powder that has been initially crushed and screened is mixed with a pre-prepared dilute acid solution in a solid-liquid state, and stirred with a magnetic stirrer for 4 hours to allow the mixture to fully react and dissolve, thereby forming a humic acid extract; the inner turntable (2) rotates at a low speed under the control of a drive motor (23), and the humic acid extract is evenly spread on the filter cloth (22) of each filtration unit (3) through a feeding base (12); Step 2: The negative pressure chamber (110) on the fixed cylinder (11) provides negative pressure extraction power to the suction tube (4) through each guide cavity (27). At this time, each suction tube (4) performs preliminary filtration on the extract on the filter cloth (22); the swing motor drives each tensioning roller (31) to rotate back and forth in the positive and negative directions during operation, so that the filter cloth (22) is synchronously transmitted and moved; at the same time, the built-in motor (211) drives each suction tube (4) to rotate through the transmission shaft (29). The top pressure plate (46) on the suction tube (4) can generate periodic impact force in the rotational contact with the rubbing tooth plate (45), so that the suction tube (4) generates corresponding vibration, and a part of the filter residue falls to the tip of the suction tube (4) by inertia, and is discharged through the filter outlet (212) on the inner turntable (2); Step 3: After the initial filtration, the filter residue rotates with the inner turntable (2) to the rinsing pipe (14), and the rinsing pipe (14) rinses the filter residue through the spray pipe (15) to remove the mother liquor remaining on the surface of the filter residue. Then, the inner turntable (2) rotates to the rinsing pipe (18), thereby rinsing the filter residue on the filter cloth (22) through each nozzle (19); Step 4: Repeat steps 2 and 3, and increase the suction intensity of the suction pipe (4) until the residual solvent and insoluble impurities on the surface of the filter residue are completely removed; Step 5: Collect the filter residue through the outlet (111) below the fixed cylinder (11), and then dry and freeze it.

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