A continuous vertical high-solid anaerobic fermentation system and working method thereof

Abstract

The present invention relates to the technical field of anaerobic fermentation, and specifically to a continuous vertical high-solid anaerobic fermentation system and a working method thereof, comprising a fermenter, a mixing tank connected to a feed port of the fermenter, a dehydrator connected to a feed port of the fermenter, a mixer connected to a feed port of the dehydrator, an induced draft fan connected to a gas outlet of the fermenter, a biogas storage cabinet connected to the gas outlet of the induced draft fan, and a biological desulfurization tower, a dehydration tower and a decarbonization tower connected in sequence to the biogas storage cabinet; the technical scheme moves an inner rod along the axis of the rod body toward one end away from the main axis until it can contact the side wall of a side wall scraper, so that the side wall scraper can move in contact with the inner wall of the fermenter body when needed, so as to scrape off raw materials attached to the inner wall of the fermenter body, and also avoid the side wall scraper from causing long-term friction and heat generation to affect the temperature of the fermentation reaction.

Description

Technical Field

[0001] The invention relates to the technical field of anaerobic fermentation, and in particular to a continuous vertical high-solid anaerobic fermentation system and a working method thereof. Background Art

[0002] Anaerobic fermentation is a biological reaction process in which organic matter is converted into biogas, carbon dioxide and organic acids under anaerobic conditions by the action of anaerobic microorganisms. This process can be widely used in the treatment of organic wastes such as agricultural waste, urban garbage, and industrial wastewater, and has the advantages of reducing waste volume, alleviating environmental pollution, and generating energy.

[0003] The dry anaerobic fermentation biogas stirring device is mainly composed of a tank body, a driving device, a stirrer, a rake and other structures. The material is fed in from top to bottom and multiple feeding pipelines are evenly distributed on the top of the tank to ensure that the material enters the tank evenly and synchronously. Multiple layers of stirrers and rakes are arranged in the tank. The rake at the bottom of the tank body continuously scrapes the bottom biogas residue to the center of the tank bottom and discharges it as the main shaft rotates.

[0004] However, the rake in the prior art cannot clean the raw materials attached to the fermentation tank wall, and the rake always moves in close contact with the bottom wall of the fermentation tank, generating large friction, and the rotating shaft pressure of the rotary driver driving the rake frame to rotate is always large, affecting the service life of the equipment. Summary of the invention

[0005] In view of the above problems, it is necessary to provide a continuous vertical high-solid anaerobic fermentation system and a working method thereof to address the problems of the prior art.

[0006] In order to solve the problems of the prior art, the technical solution adopted by the present invention is:

[0007] A continuous vertical high-solid anaerobic fermentation system, comprising a fermentation tank, a mixing tank connected to a feed inlet of the fermentation tank, a dehydrator connected to a feed outlet of the fermentation tank, a mixer connected to a solid material outlet of the dehydrator, an induced draft fan connected to a gas outlet of the fermentation tank, a biogas storage cabinet connected to an output outlet of the induced draft fan, and a biological desulfurization tower, a dehydration tower and a decarbonization tower connected in sequence to the biogas storage cabinet;

[0008] The fermentation tank comprises a fermentation tank body, and a main shaft rotatably mounted on the axis of the fermentation tank body, a feed inlet and an air outlet are arranged on the top of the fermentation tank body, the bottom of the fermentation tank body has an inner diameter that decreases downward, a discharge port and a screw conveyor are arranged at the bottom of the fermentation tank body, a plurality of stirrers are arranged on the main shaft, a rake is arranged at the bottom of the main shaft, the stirrer comprises a first sleeve coaxially mounted on the main shaft, a horizontally extending rod body is arranged on the periphery of the first sleeve, a plurality of stirring blades extending radially along the rod body are arranged on the rod body, and an inner rod is slidably mounted in the rod body; a vertically extending side wall scraper is arranged in the fermentation tank body, and the upper and lower ends of the side wall scraper are slidably mounted on the upper ring rail and the lower ring rail, the upper ring rail and the lower ring rail are arranged around the inner wall of the fermentation tank body, and the side wall scraper is attached to the inner wall of the fermentation tank body;

[0009] The sum of the length of the rod body, the width of the side scraper and the radius of the main shaft is not greater than the inner diameter of the fermenter body, so that the inner rod and the side scraper are spaced apart in the initial state;

[0010] The inner rod moves along the axis of the rod body toward one end away from the main shaft until it contacts the side wall of the side wall scraper and pushes the side wall scraper to move.

[0011] Preferably, a rotary driver for driving the main shaft to rotate is arranged on the top of the fermentation tank body, a through hole is arranged in the main shaft, which passes through the main shaft along the axis, a secondary shaft is coaxially arranged in the main shaft, and a linear driver for driving the secondary shaft to move along the axis of the main shaft is arranged on the top of the fermentation tank body; a first contact head and a second contact head are arranged at both ends of the inner rod, the diameters of the first contact head and the second contact head are the same as the inner diameter of the rod body, the second contact head is located at the end of the inner rod facing the main shaft, a first connecting hole with the same diameter as the second contact head is arranged on the main shaft, and the end of the second contact head extending from the first connecting hole to the inside of the main shaft is a round head; the secondary shaft is provided with thin rods of the same number as the agitators, the thin rods pass through the gaps between the second contact heads, and the secondary shaft is provided with an arc-shaped end on the upper side of the thin rods, and the arc-shaped end fits the outer wall of the second contact head.

[0012] Preferably, a guide ring is coaxially arranged in the rod body, the inner diameter of the guide ring is the same as the inner diameter of the inner rod, a second spring is arranged in the rod body, the second spring elastically connects the guide ring and the second contact head, and the elastic force of the second spring causes the second contact head to move into the main shaft.

[0013] Preferably, a limiting plate protruding from the peripheral side of the outer wall of the inner rod is provided at one end of the first contact head facing the side wall scraper, and the limiting plate is used to limit the second contact head.

[0014] Preferably, the rake feeder includes a second sleeve coaxially installed on the main shaft, a plurality of rake frames are arranged on the circumference of the second sleeve, at least two mounting grooves are arranged on the side of the rake frame facing the main shaft, and the mounting grooves extend to the inside of the main shaft through the waist-shaped hole arranged at the bottom of the main shaft; a connecting block is coaxially arranged below the secondary shaft, and a side socket with the same diameter as the mounting groove is arranged on the circumference of the connecting block, and the mounting groove is inserted in the side socket, and the rake feeder follows the secondary shaft to move along the axis of the main shaft.

[0015] Preferably, a guide shaft is coaxially arranged at the top of the connecting block, and the guide shaft is inserted into a first axial hole coaxially arranged at the bottom of the secondary shaft. A second axial hole is coaxially arranged at the bottom of the secondary shaft, and the inner diameter of the second axial hole is larger than the inner diameter of the first axial hole. A first spring is arranged in the second axial hole, and the first spring elastically connects the secondary shaft and the connecting block.

[0016] Preferably, at least one straight rod extending vertically upward is provided at the top of the connecting block, and a limiting head is provided at the top of the straight rod, and the diameter of the limiting head is larger than the diameter of the straight rod; a first insertion hole which is in the same straight line as the axis of the straight rod is provided at the bottom of the secondary shaft, and the diameter of the first insertion hole is the same as the diameter of the limiting head, a second insertion hole is coaxially provided at the top of the first insertion hole, and the inner diameter of the second insertion hole is the same as the diameter of the limiting head, the straight rod is inserted in the first insertion hole, and the limiting head is inserted in the second insertion hole.

[0017] Preferably, a plurality of mounting grooves are provided below the rake frame, and the mounting grooves are evenly spaced along the length direction of the rake frame. Rake teeth are provided in each mounting groove, and guide rods are provided on the tops of the rake teeth. The guide rods are inserted into guide holes provided on the mounting grooves, and the rake teeth always fit the bottom inner wall of the fermentation tank body under the action of gravity.

[0018] Preferably, an inclined surface is provided on the upper side of the lower ring rail, and the inner diameter of the inclined surface gradually decreases toward the bottom of the fermentation tank body; the bottom end of the side wall scraper is in contact with the inclined surface of the lower ring rail.

[0019] A working method of the above-mentioned continuous vertical high-solid anaerobic fermentation system comprises the following steps:

[0020] Step 1: Place the material to be fermented into a mixing tank and mix evenly;

[0021] Step 2: The mixed materials are sent to a fermentation tank for fermentation. The biogas produced by fermentation is extracted by an induced draft fan and then passes through a biological desulfurization tower for desulfurization, a dehydration tower for dehydration, and a decarbonization tower for removal of carbon dioxide;

[0022] Step 3: The solid-liquid mixture after fermentation in the fermentation tank is dehydrated in a dehydrator, the biogas slurry is sent back to the mixing tank, and the biogas residue is sent to the mixer after aerobic composting;

[0023] Step 4: The materials mixed in the mixer are sent to the granulator for granulation.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] Firstly, a side wall scraper for cleaning waste material attached to the inner wall of the fermentation tank body is arranged in the fermentation tank body of the present invention. When the side wall scraper moves, the raw materials attached to the inner wall of the fermentation tank body can be scraped off so that the raw materials can be transported to the discharge port by the rake, thereby keeping the inner wall of the fermentation tank body clean and improving the utilization efficiency of the residue material.

[0026] Secondly, when the side wall scraper in the present invention contacts the movable inner rod arranged in the rod body, it can move to fit the inner wall of the fermentation tank body. The movement of the inner rod is controlled by the secondary shaft in the main shaft. The side wall scraper can move with the agitator only when needed. When the agitator stirs the raw materials normally, the side wall scraper remains stationary, thereby avoiding the side wall scraper from moving for a long time during the fermentation process, generating friction heat that affects the temperature of the fermentation reaction.

[0027] Thirdly, the rake in the present invention is connected to the secondary shaft through a connecting block, and the rake can adjust the distance from the inner wall of the fermentation tank body, thereby reducing friction and also reducing the resistance encountered when the main shaft rotates. When the rake moves up, the rake teeth on the rake frame move down to maintain the stirring effect on the raw materials at the bottom of the fermentation tank body. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of a continuous vertical high-solid anaerobic fermentation system;

[0029] Figure 2 This is the front view of the fermentation tank;

[0030] Figure 3 yes Figure 2 Cross-sectional view at AA of FIG.

[0031] Figure 4 yes Figure 3 A partial enlarged view of point B;

[0032] Figure 5 yes Figure 3 A partial enlarged view of point C;

[0033] Figure 6 yes Figure 3 A partial enlarged view of point D;

[0034] Figure 7 yes Figure 3 A three-dimensional cross-sectional view of

[0035] Figure 8 yes Figure 7 A local enlarged view of point E;

[0036] Fig. 9 is a front view of the fermentation tank in the second working state;

[0037] Fig.10 yes Fig. 9 A cross-sectional view at FF of FIG.

[0038] Fig.11 Fig.10 A local enlarged view of point G;

[0039] Fig.12 Fig.10 A local enlarged view of the H position;

[0040] Fig.13 Fig.10 A local enlarged view of location I;

[0041] Fig.14 yes Fig.10 A partial enlarged view of point J.

[0042] The numbers in the figure are: 1, fermentation tank body; 11, feed port; 12, air outlet; 13, discharge port; 14, screw conveyor; 15, rotary drive; 16, linear drive; 2, main shaft; 21, secondary shaft; 211, thin rod; 212, arc end; 213, first shaft hole; 214, second shaft hole; 215, first insertion hole; 216, second insertion hole; 22, first connecting hole; 23, waist hole; 24, connecting block; 241, side plug hole; 242, guide shaft; 243, first spring; 244, straight rod; 245, limit head; 3, agitator; 31, first sleeve; 32, rod body; 321, guide ring; 32 2. Second spring; 33. Stirring blade; 34. Inner rod; 341. First contact head; 342. Second contact head; 343. Limit plate; 4. Rake feeder; 41. Second sleeve; 411. Insert rod; 42. Rake frame; 421. Mounting groove; 422. Guide hole; 43. Rake tooth; 431. Guide rod; 5. Side wall scraper; 51. Upper ring rail; 52. Lower ring rail; 521. Inclined surface; 6. Mixing tank; 7. Dehydrator; 8. Feeding conveyor belt; 9. Batching machine; 10. Mixer; 20. Granulator; 30. Packaging machine; 40. Induced draft fan; 50. Biogas storage cabinet; 60. Biodesulfurization tower; 70. Dehydration tower; 80. Decarbonization tower. DETAILED DESCRIPTION

[0043] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0044] Reference Figures 1 to 14 :

[0045] A continuous vertical high-solid anaerobic fermentation system comprises a fermentation tank, a mixing tank 6 connected to a feed inlet 11 of the fermentation tank, a dehydrator 7 connected to a discharge port 13 of the fermentation tank, a mixer 10 connected to a solid material outlet of the dehydrator 7, an induced draft fan 40 connected to a gas outlet 12 of the fermentation tank, a biogas storage cabinet 50 connected to an output port of the induced draft fan 40, and a biological desulfurization tower 60, a dehydration tower 70 and a decarbonization tower 80 connected in sequence to the biogas storage cabinet 50.

[0046] Specifically, the feed port 11 of the fermentation tank is connected to the mixing tank 6, and the mixing tank 6 is mainly used for mixing vegetable straws, livestock and poultry excrement and suction excrement. The mixed materials enter the fermentation tank for fermentation.

[0047] The discharge port 13 of the fermentation tank is connected to a dewatering machine 7, the liquid outlet of the dewatering machine 7 is connected to a mixing tank 6, and the biogas slurry is sent back to the mixing tank 6, the solid outlet of the dewatering machine 7 is connected to a mixer 10, and a feeding conveyor belt 8 is arranged between the solid outlet of the dewatering machine 7 and the input port of the mixer 10, and the feeding conveyor belt 8 is used to transport the biogas residue removed from the dewatering machine 7 to the mixer 10, and a batching machine 9 is also arranged on the upper side of the feeding conveyor belt 8, and the biogas residue is transported to the mixer 10 through the feeding conveyor belt 8 after aerobic composting, and the batching machine 9 is a fertilizer batching machine. The output port of the mixer 10 is connected to a granulator 20, which is mainly used for granulating fertilizers, and the output port of the granulator 20 is connected to a packaging machine 30, which bags and seals the granulated fertilizers.

[0048] An induced draft fan 40 is connected to the top of the fermentation tank, and an output port of the induced draft fan 40 is connected to a biogas storage cabinet 50, and an output port of the biogas storage cabinet 50 is connected to a biological desulfurization tower 60, a dehydration tower 70 and a decarbonization tower 80 in sequence.

[0049] In this embodiment, the mixing tank 6, the dewatering machine 7, the feeding conveyor belt 8, the batching machine 9, the mixer 10, the granulator 20, the packaging machine 30, the induced draft fan 40, the biogas storage tank 50, the biological desulfurization tower 60, the dewatering tower 70 and the decarbonization tower 80 are all existing technologies.

[0050] The fermentation tank comprises a fermentation tank body 1, and a main shaft 2 rotatably mounted on the axis of the fermentation tank body 1, a feed inlet 11 and an air outlet 12 are arranged on the top of the fermentation tank body 1, the bottom of the fermentation tank body 1 has an inner diameter that decreases downward, a discharge port 13 and a screw conveyor 14 are arranged at the bottom of the fermentation tank body 1, a plurality of stirrers 3 are arranged on the main shaft 2, a rake 4 is arranged at the bottom of the main shaft 2, the stirrer 3 comprises a first sleeve 31 coaxially mounted on the main shaft 2, a horizontally extending rod body 32 is arranged on the circumference of the first sleeve 31, and a plurality of radially extending rods 32 are arranged on the rod body 32 A stirring blade 33 and an inner rod 34 are slidably installed in the rod body 32; a vertically extending side wall scraper 5 is arranged in the fermentation tank body 1, and the upper and lower ends of the side wall scraper 5 are slidably installed on the upper ring rail 51 and the lower ring rail 52. The upper ring rail 51 and the lower ring rail 52 are arranged around the inner wall of the fermentation tank body 1, and the side wall scraper 5 fits the inner wall of the fermentation tank body 1; the sum of the length of the rod body 32, the width of the side wall scraper 5 and the radius of the main shaft 2 is not greater than the inner diameter of the fermentation tank body 1; when the inner rod 34 moves along the axis of the rod body 32 to the end away from the main shaft 2 until it contacts the side wall of the side wall scraper 5, it can push the side wall scraper 5 to move.

[0051] The fermentation system of the present invention includes a fermentation tank body 1, and the raw materials can enter the fermentation tank body 1 through the feed port 11 at the top of the fermentation tank body 1. The main shaft 2 rotatably installed at the axis of the fermentation tank body 1 is used to drive the agitator 3 and the rake 4 to rotate. The agitator 3 rotates to stir and mix the raw materials inside the fermentation tank body 1, so that the mixing is more comprehensive and the fermentation efficiency is improved. The rake 4 rotates with the main shaft 2 to continuously scrape the bottom waste to the discharge port 13 at the center of the tank bottom, and cooperates with the screw conveyor 14 to discharge the waste. The fermentation tank body 1 in this embodiment is provided with an upper ring rail 51 and a lower ring rail 52. The rail 51 is located at the top of the inner wall of the fermentation tank body 1, and the lower ring rail 52 is located at the bottom of the inner wall of the fermentation tank body 1. The upper and lower ends of the side wall scraper 5 are slidably installed on the upper ring rail 51 and the lower ring rail 52. When the side wall scraper 5 moves, it can surround the inner wall of the fermentation tank body 1. One side of the side wall scraper 5 fits the inner wall of the fermentation tank body 1. Therefore, when the side wall scraper 5 moves, the raw materials attached to the inner wall of the fermentation tank body 1 can be scraped off, so that it can be transported to the discharge port 13 by the rake 4. In order to avoid the long-term movement of the side wall scraper 5 during the fermentation process, the movement of the side wall scraper 5 in this embodiment requires the drive of the agitator 3. The stirrer 3 is mounted on the main shaft 2 through the first sleeve 31. The rod body 32 on the side of the first sleeve 31 and the stirring blades 33 on the rod body 32 can stir the materials in the fermentation tank body 1 when the main shaft 2 rotates. The inner rod 34 is slidably mounted in the horizontal rod body 32. Since the sum of the length of the rod body 32, the width of the side wall scraper 5 and the radius of the main shaft 2 is not greater than the inner diameter of the fermentation tank body 1, the rod body 32 will not contact the side wall scraper 5. When the inner rod 34 is located inside the rod body 32, the main shaft 2 drives the stirrer 3 to rotate, and the rod body 32 does not contact the side wall scraper 5. The side wall scraper 5 has no power source and thus keeps its position unchanged. When the side wall scraper 5 needs to move to clean the inner wall of the fermentation tank body 1, the inner rod 34 can move in the rod body 32 toward the inner wall of the fermentation tank body 1, and the inner rod 34 protrudes from one end of the rod body 32 toward the inner wall of the fermentation tank body 1, so that the inner rod 34 can contact one side of the side wall scraper 5, so that the side wall scraper 5 can move under the push of the inner rod 34, and the side wall scraper 5 and the agitator 3 can move synchronously. The side wall scraper 5 moves at least one circle around the inner wall of the fermentation tank body 1 to complete the cleaning of the inner wall of the fermentation tank body 1. After the cleaning is completed, the inner rod 34 can be retracted into the rod body 32 to stop the movement of the side wall scraper 5. There is at least one side wall scraper 5 in this embodiment, and it can also be set according to the number of rod bodies 32 to ensure the cleaning effect of the inner wall of the fermentation tank body 1.

[0052] In order to solve the problem of how to realize the movement of the inner rod 34 in the rod body 32, the following features are specifically provided:

[0053] A rotary driver 15 for driving the main shaft 2 to rotate is arranged on the top of the fermentation tank body 1, a through hole is arranged in the main shaft 2 and passes through the main shaft 2 along the axis, a secondary shaft 21 is coaxially arranged in the main shaft 2, and a linear driver 16 for driving the secondary shaft 21 to move along the axis of the main shaft 2 is arranged on the top of the fermentation tank body 1; a first contact head 341 and a second contact head 342 are arranged at both ends of the inner rod 34, and the diameters of the first contact head 341 and the second contact head 342 are the same as the inner diameter of the rod body 32, and the second contact head 342 is located at The inner rod 34 faces one end of the main shaft 2, and the main shaft 2 is provided with a first connecting hole 22 with the same diameter as the second contact head 342, and the second contact head 342 passes through the first connecting hole 22 and extends to one end of the main shaft 2 with a round head; the secondary shaft 21 is provided with thin rods 211 with the same number as the agitator 3, and the thin rods 211 pass through the gaps between the second contact heads 342. The secondary shaft 21 is located on the upper side of the thin rods 211 and the arc-shaped end 212 fits the outer wall of the second contact head 342.

[0054] A guide ring 321 is coaxially arranged inside the rod body 32. The inner diameter of the guide ring 321 is the same as the inner diameter of the inner rod 34. A second spring 322 is arranged inside the rod body 32. The second spring 322 elastically connects the guide ring 321 and the second contact head 342. The elastic force of the second spring 322 causes the second contact head 342 to move into the main shaft 2.

[0055] In this embodiment, the main shaft 2 is driven to rotate by the rotary driver 15 on the top of the fermentation tank body 1, and the sub-shaft 21 is inserted into the main shaft 2. The sub-shaft 21 remains stationary when the main shaft 2 rotates. The linear driver 16 set on the top of the fermentation tank body 1 is used to drive the sub-shaft 21 to move vertically inside the main shaft 2. The second contact head 342 at one end of the inner rod 34 enters the main shaft 2 through the first connecting hole 22 on the main shaft 2. The thin rod 211 of the sub-shaft 21 passes through a plurality of second contact heads 342 at the same height. When the linear driver 16 drives the sub-shaft 21 to move downward, the arc-shaped end 212 on the upper side of the thin rod 211 and the round end of the second contact head 342 are connected. The inner rod 34 is contacted and pushed to move toward the inner wall of the fermentation tank body 1 under the action of pressure. At this time, the second contact head 342 compresses the second spring 322, and the first contact head 341 at the other end of the inner rod 34 protrudes from the top of the rod body 32, and follows the rotation of the agitator 3 to contact one side of the side wall scraper 5, thereby pushing the side wall scraper 5 to move. The secondary shaft 21 in this embodiment can simultaneously drive the inner rods 34 of all agitators 3 to move. When the secondary shaft 21 moves upward, the inner rod 34 is reset under the action of the second spring 322, and the contact with the side wall scraper 5 is released, so that the side wall scraper 5 is stationary, avoiding continuous friction with the inner wall of the fermentation tank body 1 to cause heat generation and affect the temperature of the fermentation reaction. The rotary driver 15 in this embodiment can be a servo motor, and the linear driver 16 can be a cylinder.

[0056] In order to enable the arc-shaped end 212 of the secondary shaft 21 to push the second contact head 342 when it moves downward, the arc surface of the round end of the second contact head 342 must be kept in contact with the secondary shaft 21. In order to solve the problem of how to ensure that the arc surface of the round end of the second contact head 342 is kept inside the main shaft 2 after the second contact head 342 is reset, the following features are specifically set:

[0057] A limiting plate 343 protruding from the outer wall circumference of the inner rod 34 is provided at one end of the first contact head 341 facing the side wall scraper 5 , and the limiting plate 343 is used to limit the second contact head 342 .

[0058] In this embodiment, a limiting plate 343 is further provided on the outer wall of the first contact head 341. When the limiting plate 343 is in contact with the rod body 32, it limits the position of the second contact head 342, so as to keep the arc surface of the round head end of the second contact head 342 located inside the main shaft 2 in contact with the arc end 212 of the secondary shaft 21.

[0059] In order to solve the problem of preventing the rake 4 from moving along the bottom of the fermentation tank body 1 for a long time, the following features are specifically set:

[0060] The rake feeder 4 includes a second sleeve 41 coaxially installed on the main shaft 2, and a plurality of rake frames 42 are arranged around the second sleeve 41. At least two plug rods 411 are arranged on the side of the rake frame 42 facing the main shaft 2. The plug rods 411 extend into the inside of the main shaft 2 through the waist-shaped holes 23 arranged at the bottom of the main shaft 2; a connecting block 24 is coaxially arranged below the secondary shaft 21, and a side plug hole 241 with the same diameter as the plug rod 411 is arranged around the connecting block 24. The plug rod 411 is inserted into the side plug hole 241, and the rake feeder 4 moves along the axis of the main shaft 2 following the secondary shaft 21.

[0061] In this embodiment, a connecting block 24 is further connected below the secondary shaft 21, and the second sleeve 41 of the rake feeder 4 is inserted into the side plug hole 241 on the connecting block 24 through the plug rod 411, so that the rake feeder 4 can follow the connecting block 24 and the secondary shaft 21 to move along the axis of the main shaft 2. When the agitator 3 stirs the raw materials normally, the linear drive 16 drives the secondary shaft 21 to move upward, and the inner rod 34 is located in the rod body 32 and does not contact the side wall scraper 5. The upward movement of the secondary shaft 21 drives the connecting block 24 and the rake feeder 4 to move upward, so that the rake frame 42 of the rake feeder 4 moves upward, and does not directly contact the bottom of the inner wall of the fermentation tank body 1, and only keeps stirring. The function of the invention is to avoid a large amount of heat generated by friction and affect the temperature of the fermentation reaction. When the linear drive 16 drives the secondary shaft 21 to move downward, the inner rod 34 protrudes from the top of the rod body 32 and contacts the side wall scraper 5. The connecting block 24 and the rake 4 move downward to the rake frame 42 to fit the bottom of the inner wall of the fermentation tank body 1, thereby continuously scraping the bottom waste to the discharge port 13 at the center of the tank bottom, and cooperating with the screw conveyor 14 to discharge the waste. The rake 4 in this embodiment can adjust the distance from the inner wall of the fermentation tank body 1, reduce friction, and also reduce the resistance of the main shaft 2 when rotating, so as to protect the linear drive 16. In this embodiment, the side plug hole 241 is an annular groove coaxial with the secondary shaft 21.

[0062] In order to solve the problem of how to ensure the degree of fit between the rake 4 and the inner wall of the discharge port 13, the following features are specifically set:

[0063] A guide shaft 242 is coaxially arranged at the top of the connecting block 24, and the guide shaft 242 is inserted into a first shaft hole 213 coaxially arranged at the bottom of the secondary shaft 21. A second shaft hole 214 is coaxially arranged at the bottom of the secondary shaft 21, and the inner diameter of the second shaft hole 214 is larger than the inner diameter of the first shaft hole 213. A first spring 243 is arranged in the second shaft hole 214, and the first spring 243 elastically connects the secondary shaft 21 and the connecting block 24.

[0064] The connecting block 24 in this embodiment is elastically connected to the secondary shaft 21 through the first spring 243, and the side plug hole 241 is inserted into the first shaft hole 213 for guidance. When the secondary shaft 21 moves down to the point where the rake frame 42 of the rake device 4 has been in contact with the inner wall of the fermentation tank body 1, the secondary shaft 21 can continue to move downward relative to the connecting block 24. The subsequent movement of the secondary shaft 21 can compress the first spring 243, so that the second contact head 342 of the inner rod 34 can completely enter the rod body 32. The elastic force of the first spring 243 also ensures that the rake frame 42 is in contact with the inner wall of the fermentation tank body 1, thereby ensuring the raking effect.

[0065] In order to solve the problem of how to ensure that the upward movement of the secondary shaft 21 can drive the rake frame 42 to overcome the gravity of the raw materials and move upward, the following features are specifically set:

[0066] At least one straight rod 244 extending vertically upward is arranged at the top of the connecting block 24, and a limiting head 245 is arranged at the top of the straight rod 244, and the diameter of the limiting head 245 is larger than the diameter of the straight rod 244; a first insertion hole 215 which is in the same straight line as the axis of the straight rod 244 is arranged at the bottom of the secondary shaft 21, and the diameter of the first insertion hole 215 is the same as the diameter of the straight rod 244, and a second insertion hole 216 is coaxially arranged at the top of the first insertion hole 215, and the inner diameter of the second insertion hole 216 is the same as the diameter of the limiting head 245, the straight rod 244 is inserted in the first insertion hole 215, and the limiting head 245 is inserted in the second insertion hole 216.

[0067] The connecting block 24 in this embodiment is provided with a straight rod 244 and a limit head 245, which are respectively inserted into the first insertion hole 215 and the second insertion hole 216 of the secondary shaft 21. When the secondary shaft 21 moves up to the limit head 245 abutting against the bottom of the second insertion hole 216, the secondary shaft 21 pulls the connecting block 24 to move up synchronously, thereby overcoming the pressure of the raw material on the rake 4, and causing the rake 4 to move up synchronously following the first connecting hole 22.

[0068] In order to achieve the purpose of stirring the raw materials between the rake frame 42 and the inner wall of the discharge port 13 after the rake 4 moves upward, the following features are specifically set:

[0069] A plurality of mounting grooves 421 are provided below the rake frame 42, and the mounting grooves 421 are evenly spaced along the length direction of the rake frame 42. A rake tooth 43 is provided in each mounting groove 421, and a guide rod 431 is provided on the top of the rake tooth 43. The guide rod 431 is inserted into a guide hole 422 provided on the mounting groove 421. The rake tooth 43 always fits against the bottom inner wall of the fermentation tank body 1 under the action of gravity.

[0070] In this embodiment, the rake frame 42 is provided with a plurality of mounting grooves 421, and each mounting groove 421 is provided with rake teeth 43. When the rake feeder 4 and the rake frame 42 move upward, the rake teeth 43 automatically move downward under the action of gravity and keep in contact with the bottom of the inner wall of the fermentation tank body 1. When the rake feeder 4 rotates, the rake teeth 43 can stir the raw materials at the bottom of the fermentation tank body 1. When the rake frame 42 moves downward, the rake teeth 43 enter the mounting grooves 421 and rake the raw materials together with the rake frame 42.

[0071] In order to prevent the waste scraped by the side wall scraper 5 from accumulating on the lower ring rail 52, the following features are specifically provided:

[0072] An inclined surface 521 is provided on the upper side of the lower ring rail 52 , and the inner diameter of the inclined surface 521 gradually decreases toward the bottom of the fermentation tank body 1 ; the bottom end of the side wall scraper 5 is in contact with the inclined surface 521 of the lower ring rail 52 .

[0073] The lower ring rail 52 in this embodiment is provided with an inclined surface 521. The waste scraped off by the side wall scraper 5 falls on the inclined surface 521 and moves downward along the inclined surface of the inclined surface 521 without causing accumulation. The bottom end of the side wall scraper 5 is in contact with the inclined surface 521, so the side wall scraper 5 will also scrape off the waste on the surface of the inclined surface 521 when moving.

[0074] A working method of the above-mentioned continuous vertical high-solid anaerobic fermentation system comprises the following steps:

[0075] Step 1: Place the material to be fermented into the mixing tank 6 and mix evenly;

[0076] Step 2: The mixed materials are sent to a fermentation tank for fermentation. The biogas produced by fermentation is extracted by an induced draft fan 40, and then passes through a biological desulfurization tower 60 for desulfurization, a dehydration tower 70 for dehydration, and a decarbonization tower 80 for removal of carbon dioxide;

[0077] Step 3: The solid-liquid mixture after fermentation in the fermentation tank enters the dehydrator 7 for dehydration, the biogas slurry is sent back to the mixing tank 6, and the biogas residue is sent to the mixer 10 after aerobic composting;

[0078] Step 4: The materials mixed by the mixer 10 are sent to the granulator 20 for granulation.

[0079] Working principle: the raw materials enter the fermentation tank body 1 through the feed port 11 at the top of the fermentation tank body 1, the main shaft 2 drives the agitator 3 and the rake 4 to rotate, the agitator 3 rotates to mix the raw materials inside the fermentation tank body 1, the rake 4 rotates with the main shaft 2 to continuously scrape the bottom waste to the discharge port 13 at the center of the tank bottom, and cooperates with the screw conveyor 14 to discharge the waste. When it is not necessary to clean the inner wall of the fermentation tank body 1, the inner rod 34 is located inside the rod body 32, the main shaft 2 drives the agitator 3 to rotate, the rod body 32 does not contact the side wall scraper 5, and the side wall scraper 5 has no power source and therefore keeps its position unchanged. When the side wall scraper 5 needs to move to clean the inner wall of the fermentation tank body 1, the inner rod 34 can move inside the rod body 32 toward the inner wall of the fermentation tank body 1, and the inner rod 34 protrudes from one end of the rod body 32 toward the inner wall of the fermentation tank body 1, so that the inner rod 34 can contact one side of the side wall scraper 5, so that the side wall scraper 5 can move under the push of the inner rod 34, thereby realizing the synchronous movement of the side wall scraper 5 and the agitator 3, and the side wall scraper 5 moves at least one circle around the inner wall of the fermentation tank body 1 to complete the cleaning of the inner wall of the fermentation tank body 1. After the cleaning is completed, the inner rod 34 can be retracted into the rod body 32, and the side wall scraper 5 stops moving.

[0080] The above embodiments only express one or several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. A continuous vertical high-solid anaerobic fermentation system, characterized by: The invention comprises a fermentation tank, a mixing tank (6) connected to a feed inlet (11) of the fermentation tank, a dehydrator (7) connected to a feed outlet (13) of the fermentation tank, a mixer (10) connected to a solid material outlet of the dehydrator (7), an induced draft fan (40) connected to a gas outlet (12) of the fermentation tank, a biogas storage cabinet (50) connected to an output port of the induced draft fan (40), and a biological desulfurization tower (60), a dehydration tower (70) and a decarbonization tower (80) connected in sequence to the biogas storage cabinet (50); The fermentation tank comprises a fermentation tank body (1), and a main shaft (2) rotatably mounted on the axis of the fermentation tank body (1); a feed inlet (11) and an air outlet (12) are arranged on the top of the fermentation tank body (1); the bottom of the fermentation tank body (1) has an inner diameter that decreases downward; a discharge outlet (13) and a screw conveyor (14) are arranged at the bottom of the fermentation tank body (1); a plurality of stirrers (3) are arranged on the main shaft (2); a rake (4) is arranged at the bottom of the main shaft (2); the stirrer (3) comprises a first sleeve (31) coaxially mounted on the main shaft (2); a horizontally extending rod body (32) is arranged on the circumference of the first sleeve (31); a plurality of stirring blades (33) extending radially along the rod body (32) are arranged on the rod body (32); an inner rod (34) is slidably mounted inside the rod body (32); A vertically extending side wall scraper (5) is arranged in the fermentation tank body (1), and the upper and lower ends of the side wall scraper (5) are slidably mounted on an upper ring rail (51) and a lower ring rail (52). The upper ring rail (51) and the lower ring rail (52) are arranged around the inner wall of the fermentation tank body (1), and the side wall scraper (5) is in contact with the inner wall of the fermentation tank body (1); The sum of the length of the rod body (32), the width of the side wall scraper (5) and the radius of the main shaft (2) is not greater than the inner diameter of the fermentation tank body (1), so that in the initial state, the inner rod (34) and the side wall scraper (5) are spaced apart; The inner rod (34) moves along the axis of the rod body (32) toward the end away from the main shaft (2) until it contacts the side wall of the side wall scraper (5), and pushes the side wall scraper (5) to move; A rotary driver (15) for driving the main shaft (2) to rotate is arranged on the top of the fermentation tank body (1); a through hole is arranged in the main shaft (2) and passes through the main shaft (2) along the axis; a secondary shaft (21) is coaxially arranged in the main shaft (2); and a linear driver (16) for driving the secondary shaft (21) to move along the axis of the main shaft (2) is arranged on the top of the fermentation tank body (1); A first contact head (341) and a second contact head (342) are provided at both ends of the inner rod (34); the diameters of the first contact head (341) and the second contact head (342) are the same as the inner diameter of the rod body (32); the second contact head (342) is located at one end of the inner rod (34) facing the main shaft (2); a first connecting hole (22) having the same diameter as the second contact head (342) is provided on the main shaft (2); and one end of the second contact head (342) extending through the first connecting hole (22) to the inside of the main shaft (2) is a round head; The secondary shaft (21) is provided with thin rods (211) of the same number as the stirrers (3), the thin rods (211) passing through the gaps between the second contact heads (342), and the secondary shaft (21) is provided with arc-shaped ends (212) located on the upper side of the thin rods (211), and the arc-shaped ends (212) are in contact with the outer walls of the second contact heads (342); The rake (4) comprises a second sleeve (41) coaxially mounted on the main shaft (2), a plurality of rake frames (42) are arranged around the second sleeve (41), and at least two mounting grooves (421) are arranged on a side of the rake frame (42) facing the main shaft (2), and the mounting grooves (421) pass through waist-shaped holes (23) arranged at the bottom of the main shaft (2) and extend into the interior of the main shaft (2); A connecting block (24) is coaxially arranged below the secondary shaft (21), and a side plug hole (241) having the same diameter as the mounting groove (421) is arranged on the peripheral side of the connecting block (24). The mounting groove (421) is inserted into the side plug hole (241), and the rake (4) moves along the axis of the main shaft (2) following the secondary shaft (21).

2. A continuous vertical high-solid anaerobic fermentation system according to claim 1, characterized in that: A guide ring (321) is coaxially arranged inside the rod body (32); the inner diameter of the guide ring (321) is the same as the inner diameter of the inner rod (34); a second spring (322) is arranged inside the rod body (32); the second spring (322) elastically connects the guide ring (321) and the second contact head (342); the elastic force of the second spring (322) causes the second contact head (342) to move into the main shaft (2).

3. A continuous vertical high-solid anaerobic fermentation system according to claim 2, characterized in that: A limiting plate (343) protruding from the outer wall circumference of the inner rod (34) is provided at one end of the first contact head (341) facing the side wall scraper (5), and the limiting plate (343) is used to limit the second contact head (342).

4. A continuous vertical high-solid anaerobic fermentation system according to claim 1, characterized in that: A guide shaft (242) is coaxially arranged at the top of the connecting block (24), and the guide shaft (242) is inserted into a first shaft hole (213) coaxially arranged at the bottom of the secondary shaft (21). A second shaft hole (214) is coaxially arranged at the bottom of the secondary shaft (21), and the inner diameter of the second shaft hole (214) is larger than the inner diameter of the first shaft hole (213). A first spring (243) is arranged in the second shaft hole (214), and the first spring (243) elastically connects the secondary shaft (21) and the connecting block (24).

5. A continuous vertical high-solid anaerobic fermentation system according to claim 4, characterized in that: At least one straight rod (244) extending vertically upward is disposed at the top of the connection block (24), and a limiting head (245) is disposed at the top of the straight rod (244), wherein the diameter of the limiting head (245) is greater than the diameter of the straight rod (244); The bottom of the secondary shaft (21) is provided with a first insertion hole (215) which is on the same straight line as the axis of the straight rod (244); the diameter of the first insertion hole (215) is the same as the diameter of the limiting head (245); the top of the first insertion hole (215) is coaxially provided with a second insertion hole (216); the inner diameter of the second insertion hole (216) is the same as the diameter of the limiting head (245); the straight rod (244) is inserted into the first insertion hole (215), and the limiting head (245) is inserted into the second insertion hole (216).

6. The continuous vertical high-solid anaerobic fermentation system according to claim 1, characterized in that: A plurality of mounting grooves (421) are arranged below the rake frame (42), and the mounting grooves (421) are evenly spaced along the length direction of the rake frame (42). A rake tooth (43) is arranged in each mounting groove (421), and a guide rod (431) is arranged at the top of the rake tooth (43). The guide rod (431) is inserted into a guide hole (422) provided on the mounting groove (421), and the rake tooth (43) always fits against the bottom inner wall of the fermentation tank body (1) under the action of gravity.

7. The continuous vertical high-solid anaerobic fermentation system according to claim 1, characterized in that: An inclined surface (521) is provided on the upper side of the lower ring rail (52), and the inner radial direction of the inclined surface (521) gradually decreases toward the bottom of the fermentation tank body (1); The bottom end of the side wall scraper (5) is in contact with the inclined surface (521) of the lower ring rail (52).

8. A method for operating the continuous vertical high-solid anaerobic fermentation system according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Place the material to be fermented into a mixing tank (6) and mix them evenly; Step 2: The mixed materials are sent to a fermentation tank for fermentation. The biogas generated by the fermentation is extracted by an induced draft fan (40), and then passes through a biological desulfurization tower (60) for desulfurization, a dehydration tower (70) for dehydration, and a decarbonization tower (80) for removal of carbon dioxide; Step 3: the solid-liquid mixture after fermentation in the fermentation tank enters the dehydrator (7) for dehydration, the dehydrated biogas liquid is sent back to the mixing tank (6), and the dehydrated biogas residue is sent to the mixer (10) after aerobic composting; Step 4: The materials mixed by the mixer (10) are sent to the granulator (20) for granulation.

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