Equipment for solid-state continuous fermentation of livestock farm manure

Abstract

The utility model provides equipment for solid continuous fermentation of farm manure, which comprises a fermentation tank and a stirring device, the fermentation tank comprises a fermentation area, a material feeding port and a mature material discharging area, the stirring device is arranged in the fermentation area, and the stirring device can circumferentially rotate around the central axis of the fermentation tank. In the circumferential rotation direction of the stirring device, the mature material discharging area is arranged on the rear side of the material feeding opening. The device is suitable for quickly fermenting feces in a large-scale farm, the continuous feeding hole and the continuous discharging hole are additionally arranged on the basis of intermittent rotary table solid-state fermentation, and the mature material interception area capable of properly returning part of mature materials is arranged in the discharging area; the equipment capable of continuously fermenting is high in treatment efficiency, small in occupied area, stable in operation, high in speed and easy to realize automatic operation.

Description

Technical Field

[0001] This utility model relates to the field of solid-state fermentation technology, and in particular to a device for continuous solid-state fermentation of livestock manure. Background Technology

[0002] As livestock farms grow larger, manure treatment becomes increasingly difficult. The most common treatment method is composting and fermentation, which is not only time-consuming and labor-intensive but also requires significant land resources. Furthermore, livestock farm manure treatment is primarily carried out intermittently in batches, and to date, there is still no mature, continuously operating solid-state fermentation equipment.

[0003] Therefore, there is an urgent need for equipment for solid-state continuous fermentation of livestock manure. Utility Model Content

[0004] This invention provides a device for continuous solid fermentation of livestock manure, which solves the problem of non-continuous fermentation and feeding in the prior art.

[0005] This utility model discloses a solid continuous fermentation device for livestock farm manure, comprising a fermentation tank and a stirring device. The fermentation tank includes a fermentation zone, a material inlet, and a mature material outlet area. The stirring device is installed in the fermentation zone and is capable of rotating circumferentially around the central axis of the fermentation tank. The mature material outlet area is located behind the material inlet along the direction of circumferential rotation of the stirring device.

[0006] Preferably, in the solid continuous fermentation equipment for livestock manure, the stirring device includes a turning mechanism, a turning arm, and turning blades. The turning mechanism is located at the center of the fermentation tank, the turning head is connected to the turning arm, and the turning blades are provided at the bottom of the turning arm.

[0007] Preferably, in the solid continuous fermentation equipment for livestock manure, the rotating mechanism includes a stirring motor and a rotating shaft. The stirring motor is located at the bottom of the fermentation tank and on the central axis of the fermentation tank. The rotating shaft is connected to the stirring motor and to a stirring arm, which rotates around the rotating shaft in a circular motion.

[0008] Preferably, in the solid continuous fermentation equipment for livestock manure, the mature material discharge area includes a hinged door mechanism, a mature material discharge area, and a mature material retention area. The mature material discharge area is located at the bottom of the fermentation tank, and the mature material retention area is located above the mature material discharge area. The mature material retention area is located above the hinged door mechanism, which is capable of opening and closing.

[0009] Preferably, in the solid continuous fermentation equipment for livestock manure, the mature material interception area includes multiple mature material baffles, which are arranged above the mature material discharge area to divide the mature material discharge area into an open area and a closed area. The hinge door mechanism is provided above the mature material baffles.

[0010] In the aforementioned equipment for continuous solid fermentation of livestock manure, preferably, the hinge door mechanism includes a fixed hinge door and a bottom-opening hinge door. The fixed hinge door is fixedly disposed above the mature material baffle, and the bottom-opening hinge door is movably disposed above the mature material baffle.

[0011] The beneficial effects are:

[0012] When passing through the discharge zone, a portion of the mature fermented material leaves the fermentation tank through the open zone, while the other portion returns to the fermentation zone through the closed zone to mix and inoculate with the newly added material, thus starting a new round of fermentation. This achieves continuous feeding, continuous inoculation, continuous fermentation, and continuous discharge.

[0013] This invention is applicable to the rapid fermentation of manure in large-scale farms. Based on intermittent rotary solid-state fermentation, it adds a continuous feed inlet and a continuous discharge outlet. In the discharge area, a mature material retention area is set up to allow for the appropriate return of some mature material. This invention enables continuous fermentation with high processing efficiency, small footprint, stable operation, fast speed, and easy automation. Attached Figure Description

[0014] Figure 1 This is a top view of the present invention;

[0015] Figure 2 This is a side sectional view of the present invention.

[0016] 1. Fermentation tank; 1-1. Fermentation zone; 1-2. Mature material discharge zone; 1-3. Mature material retention zone;

[0017] 2. Mixing components; 2-1. Tumbling arm; 2-2. Tumbling blades; 2-3. Rotating shaft;

[0018] 3. Finished material baffle; 4. Opening area; 5. Closing area; 6. Fixed hinge door;

[0019] 7. Bottom-opening hinged door; 8. Material inlet; 9. Material in the fermentation tank. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0021] In the description of this utility model, it should be noted that the terms "above", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] This invention provides a device for continuous solid-state fermentation of livestock manure, comprising a fermentation tank and a stirring device. The fermentation tank includes a fermentation zone, a material inlet, and a mature material outlet. The stirring device is located within the fermentation zone and is capable of rotating circumferentially around the central axis of the fermentation tank. The mature material outlet is located behind the material inlet. This invention is suitable for the rapid fermentation of manure in large-scale livestock farms. Based on intermittent rotary solid-state fermentation, it adds a continuous inlet and a continuous outlet. A mature material retention zone is also provided in the outlet zone to allow for the appropriate return of some mature material. This invention provides a continuously fermenting device with high processing efficiency, small footprint, stable operation, high speed, and easy automation.

[0024] The following section uses a solid-state continuous fermentation device for livestock manure as an example to illustrate the entire technical process in detail.

[0025] like Figure 1 and Figure 2The device shown is a solid continuous fermentation equipment for livestock manure, including a fermentation tank 1 and a stirring device. The fermentation tank 1 includes a fermentation zone 1-1, a material inlet 8, and a mature material discharge area. The stirring device is installed in the fermentation zone 1-1 and is capable of rotating circumferentially around the central axis of the fermentation tank 1. The mature material discharge area is located behind the material inlet 8, along the direction of the stirring device's circumferential rotation. A blower is also installed on the side of the fermentation tank 1.

[0026] The mature material discharge area includes a hinge door mechanism, a mature material release area 1-2, and a mature material retention area 1-3. The mature material release area 1-2 is located at the bottom of the fermentation tank 1, and the mature material retention area 1-3 is located above the mature material release area 1-2. The mature material retention area 1-3 is located above the hinge door mechanism, which is capable of opening and closing.

[0027] The mature material retention area 1-3 includes multiple mature material baffles 3, which are positioned above the mature material release area 1-2 to divide the mature material release area 1-2 into an open area 4 and a closed area 5. The hinge door mechanism is located above the mature material baffles 3.

[0028] The hinge door mechanism includes a fixed hinge door 6 and a bottom-opening hinge door 7. The fixed hinge door 6 is fixedly installed above the mature material baffle 3, and the bottom-opening hinge door 7 is movably installed above the mature material baffle 3. Furthermore, the opening and closing mechanism of the hinge door is located on the outside of the outer wall of the fermentation tank 1.

[0029] Along the circumferential rotation direction of the stirring device, the mature material discharge area is located behind the material inlet 8. The maximum area of ​​the mature material discharge area occupies 15-30% of the total area of ​​the fermentation zone 1-1, and this area is further divided into intersecting open areas 4 and closed areas 5. When the fermented material passes through the open area 4, it falls into the mature material release area 1-2 and leaves the fermentation tank 1, while the material passing through the closed area 5 returns to the feeding starting line and mixes with the newly fed material. Since the fermented material contains a large number of live bacteria, this part of the material returning to the fermentation starting line can inoculate the newly fed material, thereby enabling the newly fed material to quickly enter a high-intensity fermentation state and start a new round of fermentation. This cycle repeats continuously to achieve continuous fermentation.

[0030] In actual production, the area ratio between the open zone 4 and the closed zone 5 is adjusted according to the state of the fermented material (mainly its flowability). If the material has good flowability (such as fine sand), the area ratio of the closed zone 5 needs to be increased. If the material has poor flowability (such as the material being prone to clumping or agglomeration), the area ratio of the closed zone 5 needs to be reduced, while the area ratio of the open zone 4 needs to be increased.

[0031] Preferably, the area of ​​the opening zone 4 accounts for 70% of the total area of ​​the mature material discharge zone, which would suggest that at least 70% of the material should leave the fermentation tank after passing through this discharge zone. However, this is not the case in reality. Due to the high moisture content of the material, it is prone to clumping, and a large portion of the material does not leak through the opening zone 4 when passing through the mature material discharge zone (a phenomenon known as "bridging"). Therefore, in order to ensure smooth discharge, in actual operation, in addition to increasing the area ratio of the opening zone 4, the opening angle of the opening zone 4 can also be increased. The opening angle of the mature material discharge zone can be adjusted by adjusting the opening angle of the lower hinge door 7.

[0032] The stirring device includes a turning mechanism, a turning arm 2-1, and a turning blade 2-2. The turning mechanism is located at the center of the fermentation tank 1. The turning head is connected to the turning arm 2-1, and the turning arm 2-1 has a turning blade 2-2 at its bottom. When the turning blade 2-2 moves in a circular motion, it passes over the mature material retention area 1-3.

[0033] The rotating mechanism includes a stirring motor and a rotating shaft 2-3. The stirring motor is located at the bottom of the fermentation tank 1 and on the central axis of the fermentation tank 1. The rotating shaft 2-3 is connected to the stirring motor and to a stirring arm 2-1, which rotates around the rotating shaft 2-3 in a circular motion. The rotation speed (called "angular velocity") of the stirring arm 2-1 is adjusted according to the thickness of the material 9 in the fermentation tank and the fermentation requirements.

[0034] like Figure 1 and Figure 2 As shown, the fermentation tank 1 is a cylinder, with a cylindrical rotating shaft 2-3 located at the center of the cylinder's interior. The rotating shaft 2-3 is connected to the stirring arm 2-1. In other words, the fermentation tank 1 is a ring formed by the tank wall and the rotating shaft 2-3.

[0035] The material inlet 8 is located on the outer wall of the fermentation tank 1, above the material plane. After the material enters the fermentation tank 1, it is uniformly mixed with the material 9 inside the fermentation tank by the action of the stirring blades 2-2. At the same time, the material 9 inside the fermentation tank moves in a circular motion along an arc under the push of the stirring blades 2-2. This motion mode can achieve sequential fermentation and first-in-first-out, which is beneficial to improving the quality and stability of the fermented product.

[0036] Work process:

[0037] At the beginning of fermentation, the mature material discharge area needs to be sealed for a period of time. After the material has fermented and matured, the area of ​​the mature material discharge area can be gradually opened to release the mature material.

[0038] If the amount of material or production bacteria in the fermentation system changes, the feeding speed and the residence time of the material in the fermentation tank 1 can be adjusted by adjusting the area of ​​the mature material discharge area, thereby adjusting the fermentation intensity, inoculation ratio and yield.

[0039] The retention (or cut-off) ratio of mature material is a crucial parameter affecting fermentation capacity. If the retention ratio is too low (i.e., the inoculation ratio is too low), the subsequent fermentation rate will decrease. However, if the inoculation amount is too large, the discharge ratio will decrease, also affecting yield. If other factors (such as equipment, ambient air, and temperature) are not considered, a reasonable strategy is to discharge half and retain half.

[0040] When fermentation reaches a stable operating state, the discharge rate and the feed rate remain in balance, and the material in fermentation tank 1 also reaches a balanced state, which is manifested in the material thickness and physical property parameters in fermentation tank 1 reaching a stable state.

[0041] The average residence time of fecal waste in fermentation tank 1 is relatively long, generally controlled at 50-120 hours. Depending on actual needs, it can sometimes be extended to 150 hours or even longer.

[0042] Fermentation tank 1 offers high operational flexibility, with adjustable feed and discharge rates, resulting in excellent fermentation stability. When the feed rate is approximately equal to the discharge rate (calculated on an equivalent basis), the material flow rate within fermentation tank 1 begins to increase, and the residence time of the material within fermentation tank 1 increases accordingly. Conversely, it gradually decreases as the feed rate increases.

[0043] When starting to use fermentation tank 1 to treat manure, the mature material discharge area needs to be closed, and feeding can begin after the material has fully fermented. If it is necessary to completely end a stage of operation, the mature material discharge area needs to be opened to its maximum to clear the material as quickly as possible.

[0044] Example 1

[0045] Example 1 is the treatment of manure from a pig farm with an annual output of 20,000 pigs.

[0046] A pig farm that produces 20,000 fattening pigs a year generates about 24 tons of manure (with a moisture content of about 80%) every day through dry manure cleaning.

[0047] Fermentation equipment:

[0048] The fermentation tank has an inner diameter of 12 meters, and the cylinder housing the motor has a diameter of 3 meters. The effective fermentation area of ​​the tank is 100 square meters. The fermentation tank is open at the top, with a 2.2 kW blower installed on the side. The stirring motor has a power of 55 kW. The stirring motor is mounted on a cross-shaped flat support under the fermentation tank, with the center of the cross aligned with the intersection point, and is supported by a steel column. The 3-meter diameter of this cylinder facilitates motor maintenance and also helps with motor heat dissipation.

[0049] First, 48 tons of manure were fed into the fermentation tank, along with 4.8 tons of corn cob powder and 10 tons of old manure (pre-fermented material rich in actinomycetes, with a moisture content of approximately 30%). The mixture was then stirred for three weeks (the stirring shaft rotates three times, with one rotation taking 30 minutes). Static fermentation was then carried out for 72 hours (at which point the core temperature of the material rose to approximately 73°C). At this point, the stirring and blower were activated, and continuous feeding and discharging began simultaneously. The feeding rate was a mixture of 1000 kg of manure and 100 kg of corn cob powder (containing 200 g of thermoresistant xylanase, labeled with an enzyme activity of 10000 u / g) per hour. The discharging rate was approximately 370 kg per hour (with a moisture content of approximately 57%). The discharge volume was measured by weighing after cooling.

[0050] The material in the fermentation tank must be kept at a high temperature for a certain period of time to kill viruses, insect eggs, and bacteria in the manure. When fermentation is in equilibrium, the thickness of the material should be 60-70 cm (too thin a material will make it difficult to retain heat, while too thick a material will reduce the rate of water evaporation).

[0051] This process continued for five days in the fermentation tank.

[0052] The material coming out of the fermentation tank is not yet the final mature fermented product; it still needs to undergo post-fermentation to become the final mature fermented product (marketable organic fertilizer). This post-fermentation is relatively simple and requires little space. For a farm that produces 20,000 pigs annually, only 500 square meters of storage area is needed.

[0053] The material fresh from the fermentation tank is hot, steaming, and reaches a temperature of around 60℃. After being turned and cooled, the material temperature drops to around 30℃ (0-3℃ higher than the surrounding air temperature), with a moisture content of around 57%. Then, static fermentation is carried out, with the pile thickness reaching 0.8-1.0 meters. At this stage, because the fermentable energy has decreased significantly (around 80% of the energy has been consumed in the fermentation tank), the fermentation intensity is far less than in the tank. After 4 days, the material is turned and cooled again, followed by a second static fermentation pile, this time 1.0-1.2 meters thick. After 7 days, it is turned and cooled again, followed by a third static fermentation pile, also 1.0-1.2 meters thick. After 9 days, it is turned and cooled again, yielding the final fermented product (i.e., organic fertilizer with a moisture content of 28.7%).

[0054] The high-temperature material from the fermentation tank is processed once a day. After being turned and cooled, it is then piled up for further fermentation.

[0055] In summary:

[0056] Feed 120 tons of manure + 12 tons of corn cob powder (the mixture has a moisture content of 73.6% and the corn cob powder contains 24 kg of heat-resistant xylanase) → high-intensity fermentation in a fermentation tank (the material temperature reaches a maximum of over 70℃) → discharge and cool to obtain 48.36 tons of fermented product (the material temperature is 0-3℃ higher than the ambient air temperature and the moisture content is 56.6%).

[0057] After being cooled, the material from the fermentation tank underwent 20 days of post-fermentation to obtain 24.24 tons of organic fertilizer (moisture content 28.7%).

[0058] The distribution of moisture and dry matter in the materials at each stage of the entire fermentation process is shown in Tables 1 and 2:

[0059] Table 1: Moisture and dry matter distribution of materials at each stage in Example 1 (unit: tons)

[0060]

[0061] Table 2: Contribution ratio of material fermentation at each stage in Example 1

[0062]

[0063] During the fermentation stage in the fermentation tank, 78.9% of the dry matter was lost and 77.4% of the water evaporated. The dry matter loss reflects the biochemical reactions (mainly microbial fermentation metabolism), meaning that 78.9% of the biochemical reactions occurred concentrated in the fermentation tank.

[0064] When the fermentation system reaches equilibrium, the amount of material remaining in the fermentation tank is equivalent to about 100 hours of continuous feeding (in terms of manure equivalent). That is, the average residence time of the material in the fermentation tank is about 100 hours (about 4 days), but nearly 80% of the fermentation task is completed. The production efficiency in the fermentation tank is extremely high.

[0065] The high-intensity fermentation stage is concentrated in the fermentation tank. The subsequent ripening fermentation is simpler and requires less machinery, so it can be carried out separately. This distributed fermentation method greatly improves production efficiency.

[0066] Example 2

[0067] The breeding farm is the same as in Example 1.

[0068] The post-fermentation composting site is the same as in Example 1.

[0069] The fermentation equipment is the same as in Example 1, with a total of three sets of the same manure treatment equipment.

[0070] The operation during the start-up phase is the same as in Example 1, but the feeding and discharging methods are changed to continuous feeding and discharging for 8 hours a day. The remaining 16 hours are in a static state, with neither feeding nor discharging, and the stirring motor and blower are also stopped.

[0071] The feeding rate is the same as in Example 1, that is, 1000 kg of manure and 100 kg of corn cob powder (containing 200 g of heat-resistant xylanase, labeled with enzyme activity of 10000 u / g) are fed per hour during operation.

[0072] Start the feeding process and simultaneously open the discharge valve to achieve a balance between feed and discharge. The discharge rate is approximately 288 kg per hour (measured after cooling, with a material moisture content of 46.5%).

[0073] When fermentation is in equilibrium, the thickness of the material is maintained at 55-65 cm, and the amount of material remaining in the fermentation tank is equivalent to about 100 hours of continuous feeding (in terms of manure equivalent).

[0074] This process continued for 15 days in the fermentation tank.

[0075] The material exiting the fermentation tank reaches a temperature of approximately 55℃. After being turned and cooled, the material temperature drops to 0-3℃ higher than the surrounding air temperature, and the moisture content decreases to approximately 46.5%. Then, a first static composting fermentation is performed, with a pile thickness of 1.0-1.2 meters. After 6 days, the material is turned and cooled again, followed by a second composting fermentation, with a pile thickness of 1.2-1.5 meters. After 9 days of fermentation, the material is turned and cooled again, yielding the final fermented product (i.e., organic fertilizer with a moisture content of 26.8%).

[0076] In summary:

[0077] Feed 120 tons of manure + 12 tons of corn cob powder (the mixture has a moisture content of 73.6% and the corn cob powder contains 24 kg of heat-resistant xylanase) → high-intensity fermentation in a fermentation tank (the material temperature reaches a maximum of over 70℃) → discharge and cool to obtain 34.56 tons of fermented product (the material temperature is 0-3℃ higher than the ambient air temperature and the moisture content is 46.5%).

[0078] After being cooled, the material from the fermentation tank underwent 15 days of post-fermentation to obtain 24.24 tons of organic fertilizer (moisture content 28.7%).

[0079] The distribution of moisture and dry matter in the materials at each stage of the entire fermentation process is shown in Tables 3 and 4.

[0080] Table 3: Moisture and dry matter distribution of materials at each stage in Example 2 (unit: tons)

[0081]

[0082] Table 4: Contribution ratio of material fermentation at each stage in Example 2

[0083]

[0084] During the fermentation stage in the fermentation tank, 93.2% of the dry matter was lost and 89.9% of the moisture was evaporated. Dry matter loss reflects the biochemical reactions (mainly microbial fermentation metabolism), meaning that 93.2% of the biochemical reactions occurred concentrated in the fermentation tank. The average residence time of the material in the fermentation tank was approximately 12 days (8 days longer than the operation in Example 1), yet 93.2% of the fermentation task was completed.

[0085] Because of their high degree of mechanization and automation, these three fermentation machines can be operated by a single worker. They run for 8 hours a day, requiring only daytime operation and stopping at the end of the shift, making them particularly suitable for actual production needs.

[0086] This organic fertilizer is priced at 1,800 yuan per ton (2023 price). After a year of operation, after deducting the costs of electricity, labor, and materials (mainly corn cob powder and xylanase), it can still generate a profit of nearly 2 million yuan (excluding equipment depreciation), which is very profitable.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A device for solid-state continuous fermentation of livestock manure, characterized in that, The device includes a fermentation tank and a stirring device. The fermentation tank includes a fermentation zone, a material inlet, and a mature material outlet area. The stirring device is installed in the fermentation zone and can rotate circumferentially around the central axis of the fermentation tank. The mature material outlet area is located behind the material inlet. The stirring device includes a turning mechanism, a turning arm, and a turning blade. The turning mechanism is located at the center of the fermentation tank and is connected to the turning arm. The turning blade is located at the bottom of the turning arm. The rotating mechanism includes a stirring motor and a rotating shaft. The stirring motor is located at the bottom of the fermentation tank and on the central axis of the fermentation tank. The rotating shaft is connected to the stirring motor and to the stirring lever arm. The stirring lever arm rotates in a circle around the rotating shaft. The mature material discharge area includes a hinged door mechanism, a mature material release area, and a mature material retention area. The mature material release area is located at the bottom of the fermentation tank, and the mature material retention area is located above the mature material release area. The mature material retention area is located above the hinged door mechanism, which is capable of opening and closing.

2. The equipment for solid-state continuous fermentation of livestock manure according to claim 1, characterized in that, The mature material retention area includes multiple mature material baffles, which are positioned above the mature material release area to divide the mature material release area into an open area and a closed area. The hinge door mechanism is located above the mature material baffles.

3. The equipment for solid-state continuous fermentation of livestock farm manure according to claim 2, characterized in that, The hinge door mechanism includes a fixed hinge door and a bottom-opening hinge door. The fixed hinge door is fixedly installed above the mature material baffle, and the bottom-opening hinge door is movably installed above the mature material baffle.

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