Methane production device and method for anaerobic fermentation of livestock and poultry manure

Abstract

The invention discloses a methane production device and method for anaerobic fermentation of livestock and poultry manure, and belongs to the technical field of methane production equipment. The production device comprises a fermentation tank, a mounting plate is arranged on the outer side face of the fermentation tank, and supporting rods penetrate through the four corners of the mounting plate; the upper end and the lower end of the supporting spring abut against the mounting plate and the ground correspondingly; a spiral blade for discharging slag is arranged in the slag discharging pipe, and a telescopic section which synchronously stretches out and draws back when the fermentation tank ascends and descends up and down is arranged in the middle section of the slag discharging pipe; one end of the screw rod extends into the inner cavity of the fermentation tank and is provided with a plugging head, and the other end of the screw rod extends towards the lower end of the slag discharge pipe and is connected with a driver for driving the slag discharge pipe to rotate; according to the invention, the whole biogas digester is integrated on the fermentation tank body, so that the integration degree of the whole device is higher, a traditional fermentation tank is replaced by the fermentation tank, and a discharging device is arranged at the bottom of the fermentation tank, so that the replacement efficiency of raw materials in the fermentation tank can be improved.

Description

Technical Field

[0001] This invention relates to a methane production apparatus and method for anaerobic fermentation of livestock and poultry manure, belonging to the technical field of methane production equipment. Background Technology

[0002] Anaerobic methanogens are extreme anaerobic bacteria that convert hydrogen, carbon dioxide, or simple organic matter into methane. They are widely distributed in various anaerobic environments and exhibit strong substrate specificity. They can utilize substrates such as hydrogen, carbon dioxide, formic acid, and methanol for metabolism, thereby producing methane. Currently, in many rural areas, people collect animal and plant excrement and leftover food scraps by digging their own biogas digesters and storing them. By sealing the biogas digesters, methane is produced, utilizing this principle.

[0003] Chinese patent CN106139725B discloses a biogas digester waste residue and waste liquid separation and filtration device, which includes a light floating waste residue filtration section and a residue and liquid filtration and separation section. The residue and liquid filtration and separation section are connected by an external pipeline. The device can be moved anywhere according to actual needs to process a large amount of waste residue and waste liquid, thereby reducing the environmental impact of residual discharge in biogas digesters.

[0004] In the aforementioned prior art, it is not possible to quickly and effectively replace the accumulated feces in the biogas digester. Each replacement of the raw materials in the biogas digester requires a large amount of manpower. During the replacement process, the residual biogas is difficult to collect. Furthermore, for a period of time after the raw materials are replaced, the methane production in the biogas digester will be greatly reduced due to the large amount of air entering the cleaned biogas digester. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a methane production device and method for anaerobic fermentation of livestock and poultry manure, which solves the problem of difficulty in changing raw materials in biogas digesters in the prior art.

[0006] The technical problem to be solved by the present invention is achieved by the following technical solution: a methane production device for anaerobic fermentation of livestock and poultry manure, including a fermentation tank, an installation plate is provided on the outer side of the fermentation tank, and support rods are provided through the four corners of the installation plate;

[0007] A support spring is sleeved on the support rod, with its upper and lower ends respectively abutting against the mounting plate and the ground;

[0008] A slag discharge pipe is installed at the bottom of the fermentation tank. The slag discharge pipe is equipped with spiral blades for slag discharge. The middle section of the slag discharge pipe is equipped with a telescopic section that extends and retracts synchronously when the fermentation tank is raised and lowered.

[0009] A spiral rod is disposed on the central axis of the spiral blades, with one end extending into the inner cavity of the fermenter and provided with a sealing head, and the other end extending towards the lower end of the slag discharge pipe and connected to a driver for driving its rotation.

[0010] When the fermentation tank rises, the sealing head seals the connection between the inner cavity of the fermentation tank and the slag discharge pipe.

[0011] By adopting the above technical solution, the entire biogas digester is integrated into the fermentation tank, resulting in a higher degree of integration and a smaller footprint. Furthermore, the fermentation tank replaces the traditional fermentation pool, and a discharge device at the bottom of the fermentation tank allows for the rapid removal of residue from the bottom, improving the efficiency of raw material replacement. This enables users to quickly separate the residue deposited at the bottom of the fermentation tank from the fermentation chamber, and allows for the timely replenishment of fermentation materials, achieving a long-term stable methane production without the need for complete material replacement each time. This also avoids the leakage of residual methane during each cleaning of the bottom of the fermentation chamber.

[0012] The present invention is further configured such that: the fermenter includes a fermentation chamber and a gas collection chamber, a separation plate is provided between the fermentation chamber and the gas collection chamber, and a plurality of adsorption layers are provided on the separation plate.

[0013] By adopting the above technical solution, the fermentation chamber and the gas collection chamber are separated by a separation plate. This allows the biogas produced to undergo preliminary impurity filtration through an adsorption layer before entering the gas collection chamber. This results in higher purity methane collected in the gas collection chamber, improves the quality of methane production, and reduces the difficulty of subsequent methane purification processes.

[0014] The invention is further configured such that: the spiral rod extends to the upper end of the sealing head and is connected to a plurality of stirring rods at the upper part of the sealing head, and the stirring rods are provided with guide plates.

[0015] By employing the above technical solution, the residue in the bottom area is stirred by the stirring rod, thereby preventing residue accumulation and increasing the residue discharge speed. The guide plate can prevent the formation of a central vortex when discharging residue from the fermenter, ensuring that the residue is discharged layer by layer from the bottom, improving the uniformity of residue discharge, preventing the discharge of raw materials that have not been fully fermented, and improving the utilization rate of raw materials.

[0016] The present invention is further configured such that: a central gear is provided on the separation plate, a plurality of outer ring gears mesh with the outer ring of the central gear, the central gear is connected to the helical rod, and an outer ring rod extending downward from the separation plate is provided on the outer ring gear.

[0017] By adopting the above technical solution, the raw materials in the outer ring of the fermentation tank can also be fully stirred, thereby improving the uniformity of the entire fermentation tank, reducing the stratification of the fermentation tank, and allowing methanogenic bacteria to be more evenly distributed throughout the fermentation tank, thus making full use of the raw materials in the fermentation tank and improving the methane production efficiency.

[0018] The invention is further configured such that: the bottom surface of the fermentation chamber is a hemispherical arc surface, the diameter of the arc surface is greater than 1.5 times the diameter of the guide plate, and a residue discharge channel is formed between the outer ring of the guide plate and the bottom surface of the fermentation chamber. The opening size of the discharge channel expands or shrinks as the fermentation tank is raised or lowered.

[0019] By adopting the above technical solution, the gap between the fermentation chamber and the outer ring of the guide plate forms a discharge channel for raw material residue. The size of the discharge channel opening can be adjusted by the sinking height of the fermentation chamber, allowing for better control of the residue discharge rate at the bottom of the fermentation chamber. When more raw material is added to the fermentation chamber, its overall weight increases, the sinking distance increases, the discharge channel becomes larger, and the residue discharge rate increases; conversely, the discharge rate decreases.

[0020] The present invention is further configured such that: the upper part of the fermentation tank is open and is provided with a sealing plate, a sunshade plate is connected above the sealing plate, and the sunshade plate is fixedly connected to the end of the support rod.

[0021] By adopting the above technical solution, the upper sealing plate ensures that the fermenter can remain sealed when needed. This is crucial for anaerobic or microaerobic fermentation processes, effectively preventing excessive entry of external air and avoiding interference with microbial activity. It also allows for the collection of combustible or useful gases such as biogas produced, enabling resource utilization and safety control. The sunshade provides direct physical protection for the upper part of the tank and the sealing plate, effectively blocking direct sunlight and preventing the tank from overheating due to sun exposure.

[0022] The present invention is further configured such that: an elastic sealing surface is provided in the middle of the sealing plate, and the elastic sealing surface expands and contracts with the change of gas pressure in the fermenter.

[0023] By adopting the above technical solution, gases such as methane are continuously produced during fermentation. After preliminary filtration through the adsorption layer, these gases enter the gas collection chamber, causing the internal pressure to rise continuously. The elastic sealing surface expands outward when the pressure increases, effectively increasing the internal volume of the tank and providing additional storage space for the gas, thereby buffering and releasing the internal pressure.

[0024] The present invention is further configured such that: a feeding pipe is provided on the fermentation chamber, and an exhaust pipe is connected to the gas collection chamber.

[0025] By adopting the above technical solution, it is convenient to feed raw materials and collect and process methane gas.

[0026] The present invention is further configured such that: the fermentation chamber is connected to a substrate box for enriching methanogenic bacteria into the fermentation chamber.

[0027] By adopting the above technical solution, methanogenic bacteria can be enriched into the fermentation chamber through the substrate box, which can significantly increase the methane production.

[0028] This application also relates to a method for producing methane through anaerobic fermentation of livestock and poultry manure, specifically including the following steps:

[0029] Step 1: First, pretreat the livestock and poultry manure, adjusting the carbon-to-nitrogen ratio to 20-30, while controlling the organic loading rate at 1 kgVS / m³. 3 d to 1.5kgVS / m 3 Between d, adjust the hydraulic retention time to 30-40 days to maintain the pH in the fermentation chamber between 6 and 8;

[0030] Step 2: Regularly replenish the fermentation chamber with organic matter and supplement it with synergistic substrates such as biochar or vinegar residue;

[0031] Step 3: Directional inoculation of methanogenic bacteria into the fermentation chamber;

[0032] Step 4: Regularly replenish the fermentation chamber with livestock and poultry manure, and supplement it with biochar.

[0033] By adopting the above technical solution and rationally adjusting the reaction conditions within the entire fermentation chamber, the synergistic advantage of hydrogen-nutritive and organic acid-symbiotic methanogens can be maintained. This can alleviate the inhibitory effect of ammonia nitrogen and organic acid accumulation on the entire fermentation chamber, thereby further improving the activity of methanogens within the entire fermentation chamber and ensuring the long-term stability of the methane production and the fermentation chamber itself.

[0034] The beneficial effects of this invention are:

[0035] By replacing traditional fermentation tanks with fermentation vessels, the integration of the fermentation system is improved, making maintenance of the entire system more convenient. A slag discharge pipe is installed at the bottom of the fermentation chamber, working in conjunction with spiral blades for slag removal. When residue accumulates inside the fermentation chamber, the increased overall weight causes it to move downwards along the support rod, opening the inlet of the slag discharge pipe and allowing the spiral blades to extend into the fermentation chamber to discharge the accumulated residue. Through the relative positioning of the spiral blades and the fermentation chamber as a whole, the slag discharge pipe inlet opens when residue discharge is needed, and the spiral blades extend into the fermentation chamber; when no discharge is required, the inlet of the slag discharge pipe is sealed with a plug, and the spiral blades retract into the slag discharge pipe, making the entire residue discharge process more convenient.

[0036] By setting the guide plate and the arc-shaped bottom of the fermentation chamber, the residue on the upper layer of the guide plate needs to enter the lower part of the guide plate through the discharge channel formed between the guide plate and the arc-shaped bottom of the fermentation chamber when it is discharged, and then be discharged through the slag discharge pipe. This can prevent the formation of a vortex in the middle of the fermentation chamber when the residue is discharged, which would cause a large amount of unfermented raw materials on the upper layer to be discharged, thus improving the utilization rate of raw materials.

[0037] Since the overall height of the fermentation chamber depends on the amount of raw materials stored inside, the greater the storage capacity, the heavier the fermentation chamber becomes. This leads to increased compression of the support springs and a wider opening in the discharge channel between the guide plate and the curved bottom surface, thereby increasing the discharge rate of residue. Conversely, a smaller storage capacity reduces the discharge rate. This allows users to periodically add new raw materials to the fermentation chamber and then drive the spiral blades to rotate, discharging the residue at the bottom. This achieves automatic replacement of the raw materials within the fermentation chamber, enabling the entire fermenter to continuously and stably produce methane gas.

[0038] By setting up a separation plate, the fermenter is divided into two layers: a lower fermentation chamber and an upper gas collection chamber. By setting up several adsorption layers on the separation plate, the produced gas can be initially filtered, increasing the methane content in the gas and thus reducing the difficulty of subsequent gas purification processes.

[0039] By setting an elastic sealing surface on the sealing plate, the maximum bearing limit of the gas collection chamber can be improved, preventing damage to the gas collection chamber caused by excessive or insufficient air pressure, thus enabling the gas collection chamber to achieve autonomous air pressure regulation.

[0040] By setting up a substrate box, methanogenic bacteria can be selectively enriched in the fermentation chamber, and other synergistic substrates can be replenished to the fermentation chamber regularly to maintain the overall environment inside the fermentation chamber and improve the efficiency of methane production. Attached Figure Description

[0041] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0042] Figure 2 This is a front view of the present invention;

[0043] Figure 3 This is a cross-sectional view along direction A of the present invention;

[0044] Figure 4 This is a cross-sectional view of the slag discharge pipe in the open state from direction A according to the present invention;

[0045] Figure 5 This is a three-dimensional structural diagram of the internal components of the fermenter of the present invention.

[0046] In the diagram: 1. Fermentation tank; 110. Fermentation chamber; 120. Gas collection chamber; 2. Mounting plate; 3. Support rod; 4. Support spring; 5. Slag discharge pipe; 6. Spiral blade; 7. Telescopic section; 8. Spiral rod; 9. Sealing head; 10. Driver; 11. Separation plate; 12. Adsorption layer; 13. Stirring rod; 14. Guide plate; 15. Culture medium box; 16. Outer ring gear; 17. Central gear; 18. Outer ring rod; 19. Sealing plate; 20. Sunshade plate; 21. Elastic sealing surface; 22. Feed pipe; 23. Exhaust pipe; 24. Drainage pipe; 25. Adjusting nut; 26. Instrument box. Detailed Implementation

[0047] To facilitate a clear understanding of the technical means, creative features, objectives, and effects of this invention, the invention will be further described below in conjunction with specific illustrations.

[0048] like Figure 1 and Figure 2 As shown, a methane production device for anaerobic fermentation of livestock and poultry manure includes a fermenter 1, which comprises a lower fermentation chamber 110 and an upper gas collection chamber 120. A slag discharge port is provided at the bottom of the fermentation chamber 110, connected to a slag discharge pipe 5, through which the residue at the bottom is discharged. The fermentation chamber 110 is equipped with a feed pipe 22 for adding raw materials and a substrate box 15 for adjusting the activity of microorganisms inside the fermentation chamber 110. The gas collection chamber 120 is equipped with an exhaust pipe 23 for conveying methane. The entire fermenter 1 is connected by an outer wall mounting plate 2. A support rod 3 is inserted through each of the four corners of the mounting plate 2, with the bottom of the support rod 3 fixed to the ground. The entire fermenter 1 can slide up and down along the support rod 3. A support spring 4 is sleeved on the support rod 3, with its upper and lower ends abutting against the lower surface of the mounting plate 2 and the ground. The support spring 4 is always in a compressed state, supporting the entire fermenter 1.

[0049] In this embodiment, the raw materials used can be animal and plant excrement, including but not limited to chicken manure, duck manure, cow manure, pig manure, etc.

[0050] The substrate box 15 is connected to the fermentation chamber 110. The substrate box 15 can directionally enrich and activate hydrogen-nutritive methanogens and organic acid symbiotic methanogens in the fermentation chamber 110, thereby increasing the first raw material and first strain for methane production in the fermentation chamber 110 from the bottom layer, thus improving the methane production of the entire fermentation chamber 110 and significantly improving the stability of the entire system.

[0051] Furthermore, a spiral blade 6 is installed inside the slag discharge pipe 5, and a spiral rod 8 is threaded through the central axis of the spiral blade 6. The spiral blade 6 can rotate under the drive of the spiral rod 8. The upper section of the slag discharge pipe 5 is connected to the slag discharge port at the bottom of the fermentation tank 110, and the lower section of the slag discharge pipe 5 is fixed to the ground and sealed at the bottom. At the same time, a guide pipe 24 is horizontally connected to the side wall of the lower section of the slag discharge pipe 5 to guide the residue in the slag discharge pipe 5 to a predetermined collection point. The middle section of the slag discharge pipe 5 is a telescopic section 7, which can expand or contract synchronously with the rise and fall of the entire fermentation tank 1.

[0052] One end of the screw rod 8 extends into the inner cavity of the fermenter 1 and is provided with a sealing head 9, while the other end extends to the lower end of the slag discharge pipe 5 and is connected to a driver 10 for driving its rotation.

[0053] Specifically, the lower end of the spiral rod 8 is provided with a bevel gear set for changing the transmission direction. Another spiral rod 8 that passes through the drainage pipe 24 is connected through the bevel gear set. The spiral rod 8 is also provided with spiral blades 6. One end of the spiral rod 8 is connected to the drive motor, which drives the spiral rod 8 to rotate. The two spiral rods 8 are mutually transmitted through the bevel gear.

[0054] The plugging head 9 is located in the middle section of the spiral rod 8. The plugging head 9 is conical in shape, with the cone angle facing the opening at the bottom of the fermentation chamber 110. The opening of the fermentation chamber 110 has an inclined surface with the same inclination angle as the inclined side of the plugging head 9, allowing the plugging head 9 to fit tightly against the opening at the bottom of the fermentation chamber 110 when plugging the slag discharge pipe 5. When the fermentation tank 1 rises, the plugging head 9 seals the connection between the inner cavity of the fermentation tank 1 and the slag discharge pipe 5.

[0055] like Figure 3 and Figure 4 As shown, under normal conditions, fermenter 1 is positioned where the sealing head 9 and the bottom opening of fermentation chamber 110 are in contact. When new raw materials are added inside fermentation chamber 110, the increased weight of fermenter 1 causes the support spring 4 to be compressed, and fermenter 1 sinks relative to support rod 3 and sealing head 9. The sinking distance depends on the change in the overall weight of fermenter 1; the more raw materials added, the greater the sinking distance. After fermenter 1 sinks due to the addition of raw materials, the bottom opening of fermentation chamber 110 separates from sealing head 9, and slag discharge pipe 5 connects to fermentation chamber 110. Part of the spiral blades 6 located in the upper section of slag discharge pipe 5 enters the bottom of fermentation chamber 110. At this time, by controlling the spiral rod 8 to rotate, the residue at the bottom of fermentation chamber 110 is driven into slag discharge pipe 5. The residue flows into drainage pipe 24 through slag discharge pipe 5 and is guided to a predetermined collection point through drainage pipe 24.

[0056] With the above structure, the biogas digester is integrated into the fermentation tank 1, which can slide up and down with its own weight. With the setting of the slag discharge pipe 5 and the spiral blade 6, the slag discharge can be achieved quickly, which greatly reduces the maintenance cost of the entire fermentation tank 1. The manual maintenance process does not require too much physical strength. When the raw materials are replenished, the rotation of the spiral blade 6 can be controlled to achieve automatic slag discharge.

[0057] On the other hand, since the telescopic section 7 of the slag discharge pipe 5 can expand and contract synchronously with the up-and-down movement of the fermenter 1, when the fermenter 1 descends, the telescopic section 7 contracts longitudinally and expands laterally, that is, the axial distance of the telescopic section 7 becomes shorter and the radial diameter becomes larger. At this time, the discharged residue can fall more quickly through the telescopic section 7, thereby improving the discharge efficiency of the residue. Conversely, when the fermenter 1 rises, the radial diameter of the telescopic section 7 will become smaller, thereby inhibiting the discharge of residue.

[0058] In other embodiments, the entire support rod 3 is a threaded rod with threads on its outer surface. An adjusting nut 25 is fitted on the support rod 3 above the mounting plate 2. By turning the nuts on the four support rods 3, the overall height of the fermentation tank 1 can be adjusted independently, thereby controlling the size of the opening between the bottom slag discharge pipe 5 and the fermentation chamber 110.

[0059] On the other hand, as the sealing head 9 sinks in the fermentation tank 1, it moves to the middle height of the fermentation chamber 110 relative to the fermentation tank 1. When the spiral blade 6 rotates and extracts the residue at the bottom of the fermentation chamber 110, the residue at the center of the fermentation chamber 110 sinks rapidly, forming a vortex-shaped discharge flow that converges towards the center. However, the sealing head 9 prevents the vortex-shaped discharge flow from forming an effective vortex as it moves downward. This prevents newly added raw materials from being directly guided out of the fermentation chamber 110 through the vortex-shaped discharge flow, thus ensuring that the raw materials in the upper part of the fermentation chamber 110 are fully utilized.

[0060] Furthermore, the spiral rod 8 extends upwards towards the sealing head 9 and is connected to several stirring rods 13 on the upper part of the sealing head 9. The stirring rods 13 are equipped with guide plates 14. The guide plates 14 can further prevent the generation of vortices when the fermentation chamber 110 discharges slag, so that the fermentation chamber 110 can discharge slag layer by layer.

[0061] Furthermore, the bottom surface of the fermentation chamber 110 is a hemispherical arc surface, the diameter of which is greater than 1.5 times the diameter of the guide plate 14. A residue discharge channel is formed between the outer ring of the guide plate 14 and the bottom surface of the fermentation chamber 110. The opening size of the discharge channel expands or shrinks as the fermentation tank 1 rises and falls. The gap between the fermentation chamber 110 and the outer ring of the guide plate 14 forms a discharge channel for raw material residue. The size of the discharge channel opening is adjusted by the sinking height of the fermentation chamber 110, allowing for better control of the residue discharge rate at the bottom of the fermentation chamber 110. When more raw material is added to the fermentation chamber 110, its overall weight increases, the sinking distance increases, the discharge channel becomes larger, and the residue discharge rate increases; conversely, the discharge rate decreases.

[0062] like Figure 3 As shown, a separation plate 11 is provided between the fermentation chamber 110 and the gas collection chamber 120. The separation plate 11 is generally disc-shaped and fixed by a spiral rod 8. The separation plate 11 divides the inner cavity of the fermentation tank 1 into upper and lower layers, with the gas collection chamber 120 located in the upper layer and the fermentation chamber 110 located in the lower layer. In this embodiment, three fan-shaped adsorption layers 12 are equidistantly arranged around the circumference of the separation plate 11. The adsorption material can be a material such as activated carbon that can adsorb gases such as carbon dioxide and hydrogen sulfide. By separating the fermentation chamber 110 and the gas collection chamber 120 through the separation plate 11, and in conjunction with the adsorption layers 12, the gas generated in the fermentation chamber 110 can undergo preliminary impurity filtration before entering the gas collection chamber 120, resulting in higher purity methane collected in the gas collection chamber 120, thereby reducing the difficulty of subsequent methane extraction processes.

[0063] Furthermore, a sealing ring is provided on the outer ring of the separation plate 11. The sealing ring is in contact with the inner wall of the fermentation tank 1. Since the separation plate 11 is fixed on the screw rod 8, when the fermentation tank 1 moves up and down as a whole, the separation plate 11 moves relative to the fermentation tank 1, causing the relative volume between the fermentation chamber 110 and the gas collection chamber 120 to change. When the fermentation tank 1 sinks, the volume of the fermentation chamber 110 increases and the volume of the gas collection chamber 120 decreases. Conversely, when the fermentation tank 1 rises, the volume of the fermentation chamber 110 decreases and the volume of the gas collection chamber 120 increases.

[0064] Due to the aforementioned structural characteristics, when workers add new raw materials to the fermentation chamber 110, they can quickly collect methane gas by reasonably controlling the exhaust pipe 23 connected to the gas collection chamber 120, thereby improving the methane collection efficiency.

[0065] Specifically, both the feed pipe 22 and the exhaust pipe 23 are equipped with valves for controlling their on / off states. When the feed is fed into the fermentation chamber 110 through the feed pipe 22, the fermentation tank 1 sinks as a whole, increasing its volume and decreasing the volume of the gas collection chamber 120. At this time, the valve of the exhaust pipe 23 is opened. Due to the reduced volume of the gas collection chamber 120, the separation plate 11 can act like a piston, rapidly pushing the gas in the gas collection chamber 120 through the exhaust pipe 23 into the subsequent methane collection and treatment device. When the feed material stops being transported and the valve of the feed pipe 22 is closed, as the residue at the bottom of the fermentation chamber 110 is gradually discharged, the overall weight of the fermentation tank 1 decreases, and the fermentation tank 1 gradually rises, causing the volume of the fermentation chamber 110 to decrease and the volume of the gas collection chamber 120 to increase. At this time, the valve of the exhaust pipe 23 is closed, causing the internal air pressure in the gas collection chamber 120 to decrease due to the increased volume, resulting in the rapid extraction of gas from the fermentation tank 110 into the gas collection chamber 120.

[0066] Furthermore, such as Figure 5 As shown, a central gear 17 is provided on the separating plate 11, and a plurality of outer gears 16 mesh with the outer ring of the central gear 17. The central gear 17 is connected to the spiral rod 8, and outer ring rods 18 extending downward from the separating plate 11 are provided on the outer ring gears 16. In this embodiment, a sliding groove and a slider that engage with each other are provided between the outer ring of the separating plate 11 and the inner wall of the fermentation tank 1, so that the separating plate 11 can slide up and down relative to the fermentation tank 1, but the circumferential rotation of the separating plate 11 relative to the fermentation tank 1 is restricted. The spiral rod 8 extends upward, passes through the separating plate 11, and connects with the central gear 17 provided on the upper surface of the separating plate 11, so that when the spiral blade is driven to rotate by the spiral rod 8, the central gear 17 drives the outer ring gears 16 to rotate, thereby driving the outer ring rods 18 to stir. In this embodiment, the lower end of the outer ring rod 18 extends below the liquid surface of the fermentation chamber 110 in the static state of the fermentation tank 1 by no more than one-third of the total liquid surface height of the fermentation chamber 110. That is, the outer ring rod 18 only stirs the upper and middle layers of raw materials in the fermentation chamber 110 during stirring. By rotating the outer ring rod 18, the raw materials added to the fermentation chamber 110 can be quickly stirred, thereby improving the uniform distribution of the raw materials in the fermentation chamber 110 and preventing the raw materials from accumulating in localized areas.

[0067] like Figure 3 and Figure 4As shown, the upper part of the fermentation tank 1 is open and equipped with a sealing plate 19. A sunshade plate 20 is connected above the sealing plate 19, and the sunshade plate 20 is fixedly connected to the end of the support rod 3. An elastic sealing surface 21 is provided in the middle of the sealing plate 19. The elastic sealing surface 21 expands and contracts with the gas pressure changes inside the fermentation tank 1. During the fermentation process, gases such as methane are continuously produced. After being initially filtered by the adsorption layer 12, they enter the gas collection chamber 120, causing the pressure inside the tank to continuously increase. The elastic sealing surface 21 expands outward when the pressure increases, effectively increasing the internal volume of the tank and providing additional storage space for the gas, thereby buffering and releasing the internal pressure.

[0068] Based on the above embodiments, this application also relates to a method for producing methane through anaerobic fermentation of livestock and poultry manure, specifically including the following steps:

[0069] Step 1: First, pretreat the livestock and poultry manure, adjusting the carbon-to-nitrogen ratio to 20-30, while controlling the organic loading rate at 1 kgVS / m³. 3 d to 1.5kgVS / m 3 Between d, adjust the hydraulic retention time to 30-40 days, and maintain the pH in fermentation chamber 110 between 6 and 8;

[0070] Step 2: Regularly replenish organic matter into fermentation chamber 110, and supplement it with synergistic substrates such as biochar or vinegar residue;

[0071] Step 3: Directional inoculation of methanogenic bacteria into fermentation chamber 110;

[0072] Step 4: Regularly replenish the fermentation chamber 110 with livestock and poultry manure and supplement it with biochar.

[0073] Specifically, in step one, when adjusting the carbon-nitrogen ratio of livestock and poultry manure, an appropriate amount of nitrogen fertilizer can be added for adjustment. Simultaneously, by reasonably controlling the compost moisture content, an appropriate amount of water can be added for adjustment. The moisture content should be controlled between 50% and 60%. By quantitatively adding appropriate activated carbon filler, the organic matter acceptance rate within the fermentation chamber 110 is increased, and the organic load rate is controlled at 1.2 kgVS / m³. 3 Around d is optimal.

[0074] Meanwhile, an instrument box 26 is added to the outer wall of the fermenter 1. The instrument box 26 is equipped with a liquid level detection module and a pH detection module. The liquid level detection module is connected to a guide pipe that extends to the interface height between the fermentation chamber 110 and the gas collection chamber 120. The pH detection module is connected to a guide pipe, and a pH probe is installed at the end of the guide pipe of the pH module. The end of the guide pipe extends to the area near the bottom of the fermentation chamber 110.

[0075] A sampling port is provided in the instrument box 26. The pH module contacts the liquid surface of the fermentation chamber 110 through the pH probe at the end of the guide tube to draw liquid from the fermentation chamber 110. Monitoring personnel can collect monitoring samples through the sampling port of the instrument box 26 for testing, thereby obtaining the pH value in the fermentation chamber 110. By reasonably adjusting the pH value in the fermentation chamber 110, the pH is maintained at an optimal level of around 7.2. At the same time, the detected pH value is fed back to the feeding system to control the material feeding rate of the feeding system.

[0076] In step two, by supplementing an appropriate amount of readily degradable organic matter, such as acetic acid, ethanol, and fruit and vegetable waste, the activity of symbiotic organic acid bacteria can be promoted, substrate degradation and efficient conversion of intermediate products can be enhanced, the raw materials that methanogenic bacteria can utilize can be increased, and the production efficiency of methane can be improved.

[0077] During the fermentation process, the continuously added raw materials can be monitored in real time through the instrument box to detect the liquid level inside the entire fermentation tank, thereby reasonably controlling the feeding and discharging time and ensuring that the hydraulic residence time of the raw materials in the fermentation chamber is maintained at 30-40 days.

[0078] During the fermentation process, the continuously added raw materials can be monitored in real time through the instrument box 26 to detect the liquid level inside the entire fermentation tank 1, thereby reasonably controlling the feeding and discharging time and ensuring that the hydraulic residence time of the raw materials in the fermentation chamber 110 is maintained at 30-40 days.

[0079] Fermentation tank 1 is equipped with a feeding system connected to the feed pipe 22, which can supply raw materials to the feed pipe 22 at any time. The drive 10 for discharging serves as the slag discharge system. Specifically, the system controlling the discharge, the system controlling the feeding, and the liquid level detection module are electrically connected, so that the liquid level detected by the liquid level detection module can be fed back to the feeding and slag discharge systems in real time. When the detection module detects a decrease in liquid level, it transmits a signal to the feeding system, which then feeds raw materials to the feed pipe 22. The raw materials are discharged into the fermentation chamber 110 through the feed pipe 22, which increases the overall weight of fermentation tank 1, causing fermentation tank 1 to sink. The sealing head 9 on the upper part of the spiral blade 6 and the bottom part of the fermentation chamber 110 are connected. As the fermentation chamber 110 descends, the slag discharge pipe 5 opens. Simultaneously, due to the rise in liquid level within the fermentation chamber 110, the liquid level detection module detects this rise and transmits a signal to the slag discharge system. This causes the driver 10 to drive the spiral blades 6 to rotate. At this time, as the fermentation chamber 110 sinks, the section of the spiral blades 6 extending into the fermentation chamber 110 pulls away the residue at the bottom of the fermentation chamber 110, discharging it through the slag discharge pipe 5. This causes the liquid level in the fermentation chamber 110 to drop again, and the overall weight of the fermentation tank 1 gradually decreases. At this point, the liquid level detection module transmits the liquid level signal to the feeding system again, causing the feeding system to stop feeding until the fermentation tank 1 moves back to its initial position. The slag discharge system also stops discharging, achieving automatic linkage between feeding and slag discharge.

[0080] The liquid level detection module in the instrument box 26 enables the entire fermentation tank 1 to operate synchronously with feeding and slag discharge. This allows for the effective utilization of the input raw materials, ensuring that the hydraulic retention time of the raw materials in the fermentation chamber 110 is maintained at the optimal fermentation time of 30-40 days, thus improving fermentation efficiency. Simultaneously, the automatic control of feeding and slag discharge reduces manual maintenance costs and increases production efficiency.

[0081] In step three, by employing microbial enhancement technology and selectively inoculating highly efficient methanogenic bacteria, key functional bacteria such as Methanothrix and Methanobacterium are enriched, which can significantly improve the methane yield and the fermentation rate in fermentation chamber 110.

[0082] In step four, by adding porous materials such as biochar into the fermentation chamber 110, the adhesion rate of microorganisms and direct intercellular electron transfer (DIET) can be promoted, further enhancing the activity of hydrogen-nutritive methanogens and alleviating the inhibition of the system by the accumulation of ammonia nitrogen and organic acids.

[0083] In this embodiment, by adjusting the reaction conditions within the fermentation chamber, the synergistic advantage of hydrogen-trophic and organic acid-symbiotic methanogens is maintained, ensuring that methane production and system stability remain at a high level for a long period. This results in a significant increase in methane productivity, a shorter gas production cycle, and substantial economic and environmental benefits.

[0084] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention, all of which fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A methane production device for anaerobic fermentation of livestock manure, characterized by, Include: Fermentation tank (1), the outer side of the fermentation tank (1) is provided with a mounting plate (2), and a support rod (3) is provided through the four corners of the mounting plate (2); Support spring (4), the upper and lower ends are respectively abutted on the mounting plate (2) and the ground; The residue discharge pipe (5) is provided at the bottom of the fermentation tank (1), the residue discharge pipe (5) is provided with a spiral blade (6) for discharging residue, and the middle segment of the residue discharge pipe (5) is provided with a telescopic segment (7) which is synchronous with the up-down lifting of the fermentation tank (1); The screw rod (8) is arranged on the central axis of the spiral blade (6), one end of the screw rod (8) extends into the inner cavity of the fermentation tank (1) and is provided with a plugging head (9), and the other end of the screw rod (8) extends to the lower end of the residue discharge pipe (5) and is connected with a driver (10) for driving the rotation thereof.

2. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 1, characterized in that: The fermentation tank (1) comprises a fermentation bin (110) and a gas collection bin (120), and a separation plate (11) is arranged between the fermentation bin (110) and the gas collection bin (120), and a plurality of adsorption layers (12) are arranged on the separation plate (11).

3. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 2, characterized in that: The screw rod (8) extends to the upper end of the plugging head (9) and is connected with a plurality of stirring rods (13) on the upper part of the plugging head (9), and a guide plate (14) is arranged on the stirring rod (13).

4. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 2, characterized in that: A central gear (17) is arranged on the separation plate (11), a plurality of outer ring gears (16) are engaged with the outer ring of the central gear (17), the central gear (17) is connected with the screw rod (8), and an outer ring rod (18) extending downward from the separation plate (11) is arranged on the outer ring gear (16).

5. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 3, characterized in that: The bottom surface of the fermentation bin (110) is a semispherical circular arc surface, the diameter of the circular arc surface is greater than 1.5 times the diameter of the guide plate (14), a residue discharge channel is formed between the outer ring of the guide plate (14) and the bottom surface of the fermentation bin (110), and the opening size of the discharge channel expands or shrinks with the up-down lifting of the fermentation tank (1).

6. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 1, characterized in that: The upper part of the fermentation tank (1) is open and is provided with a sealing plate (19), the upper part of the sealing plate (19) is connected with a sunshade (20), and the sunshade (20) is fixedly connected with the end of the support rod (3).

7. The apparatus for producing methane from anaerobic fermentation of livestock manure according to claim 6, wherein: The middle part of the sealing plate (19) is provided with an elastic sealing surface (21), and the elastic sealing surface (21) expands and contracts with the change of the air pressure in the fermentation tank (1).

8. The methane production device for anaerobic fermentation of livestock and poultry manure according to claim 2, characterized in that: A feeding pipe (22) is arranged on the fermentation bin (110), and an exhaust pipe (23) is communicated with the gas collection bin (120).

9. The methane production device for anaerobic fermentation of livestock manure according to claim 2, characterized in that: The fermentation bin (110) is connected with a bacteria tank (15) for enriching methanogens in the fermentation bin (110).

10. A method for producing methane from anaerobic fermentation of livestock manure, particularly applied to the methane production device as claimed in any one of claims 1-9, characterized in that, The steps include: Step one: first, the livestock and poultry manure is pretreated, the carbon-nitrogen ratio of the livestock and poultry manure is adjusted to 20-30, and the organic loading rate is controlled between 1 kgVS / m 3 d and 1.5 kgVS / m 3 d, the hydraulic retention time is adjusted to 30-40 days, and the ph in the fermentation bin (110) is maintained between 6-8; Step two: supplementing organic matter into the fermentation bin (110) at a certain time, and supplementing biological carbon or vinegar residue as a synergistic substrate; Step three: inoculating methanogens into the fermentation bin (110) in a targeted manner; Step four: supplementing livestock and poultry manure into the fermentation bin (110) at a certain time, and supplementing biological carbon.

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