A continuous dry anaerobic fermentation system

Abstract

The present invention is applicable to the technical field of anaerobic fermentation equipment, and provides a continuous dry anaerobic fermentation system, including a feeding module, a dry anaerobic reaction module and a discharging module. The feeding and discharging modules are connected by hollow tubes between two sections of spirals, and a certain height of material is retained in the hollow tube at any time, so as to meet the requirements of continuous feeding and sealing, and realize closed continuous discharging. The device of the present invention utilizes the characteristic that the moisture content of dry fermentation materials is about 60% to 80%, and cooperates with the special design in the feeding and discharging modules, so as to realize the (dry) continuous feeding and discharging and synchronous sealing requirements of high solid content waste, realize the stable operation of the dry anaerobic fermentation system, reduce the failure rate, greatly improve the volumetric gas production rate of the dry anaerobic module, increase the large amount of material processing, and reduce production costs.

Description

Technical Field

[0001] The invention belongs to the technical field of organic waste anaerobic fermentation equipment, and in particular relates to a continuous dry anaerobic fermentation. Background Art

[0002] Anaerobic fermentation technology can reduce the volume of wastes such as straw, feces, and sludge, render them harmless, and convert them into clean energy and organic fertilizer raw materials. It is one of the commonly used technologies for the resource utilization of agricultural waste. It is divided into wet anaerobic fermentation and dry anaerobic fermentation (referred to as "dry fermentation") according to the total solid (TS) content. Dry fermentation refers to anaerobic fermentation treatment technology with a TS mass fraction of 20% to 40%, and the corresponding moisture content is about 60% to 80%. Compared with wet fermentation technology, dry fermentation technology has the advantages of high volumetric gas production rate; small footprint; stable operation process, no scum, precipitation and other problems in wet process; low or no water demand, saving water resources; less production of biogas slurry, low water content of waste residue, and low subsequent treatment costs, and is increasingly favored by the market. There are patent applications for dry anaerobic fermentation equipment in China. Patent CN 102242052 B discloses a horizontal baffled dry anaerobic fermentation reaction device, patent CN 206768095 U discloses a garage-type anaerobic fermentation reactor, and patent CN 209816130 U provides a stirrer for dry anaerobic fermentation. Patents have been studied from the aspects of fermentation tank structure and stirring shaft design, mainly for batch feeding and discharging. However, the current research on dry anaerobic fermentation engineering with high solid content has found that batch dry fermentation is inconsistent with the continuous output of waste and cannot meet the requirements; the closed environment in the reactor is easily destroyed during the continuous feeding and discharging process, resulting in fermentation failure; the continuous dry anaerobic fermentation with high solid content has poor fluidity and is difficult to feed and discharge.

[0003] Therefore, how to solve the difficulties of continuous dry anaerobic fermentation in the actual process is a problem that needs to be solved urgently. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a continuous dry anaerobic fermentation system, which structurally adopts segmented feeding and discharging, hollow tube connection, and is matched with materials with a certain solid content to achieve continuous feeding and discharging of high-solid content wastes, synchronous sealing, and does not destroy the sealing environment of the reactor, thereby achieving continuous, stable and efficient gas production in the reactor.

[0005] The present invention is achieved through the following technical solutions:

[0006] Anaerobic continuous fermentation can be carried out, with convenient material loading and unloading, good sealing effect, and easy process operation. There is no need to frequently deoxygenate the anaerobic fermentation tank. During the material transmission process, the sealing status of the material channel can also be checked, and the fermentation process parameters can also be calculated according to the material situation in the hollow tube.

[0007] The present invention is implemented as follows: a continuous dry anaerobic fermentation system comprises a first feed screw, a first hollow tube, a second feed screw, a dry anaerobic reaction module, a first feed screw, a second hollow tube, and a second feed screw;

[0008] The first feeding screw comprises a first feeding barrel, a first feeding shaft, and a feeding hopper. The first feeding shaft is installed inside the first feeding barrel. The first feeding shaft and the first feeding barrel are coaxially arranged. The top of one end of the first feeding barrel is provided with the feeding hopper. The bottom of the other end of the first feeding barrel is provided with a vertically arranged first hollow tube.

[0009] The second feed screw includes a second feed barrel and a second feed shaft, the top of one end of the second feed barrel is provided with a feed port, the feed port is connected to the first feed barrel through the first hollow tube, the second feed shaft is installed inside the second feed barrel, the second feed shaft and the second feed barrel are coaxially arranged, and the lower surface of the upper end of the second feed barrel is provided with a discharge port;

[0010] The dry anaerobic reaction module comprises an anaerobic fermentation tank and an anaerobic tank discharge pipe, the top of the anaerobic fermentation tank is connected to the discharge port of the second feed cylinder, and the bottom of the anaerobic fermentation tank is connected to an anaerobic tank discharge pipe;

[0011] The first feed screw includes a first feed cylinder and a first feed shaft. The first feed cylinder is tilted. The upper surface of the lower end of the first feed cylinder has a feed port, and the feed port is connected to the anaerobic tank discharge pipe through the anaerobic tank discharge pipe. The first feed shaft is installed inside the first feed cylinder. The first feed shaft and the first feed cylinder are coaxially arranged. The upper end of the lower surface of the first feed cylinder is connected to a second hollow tube, and the second hollow tube is vertically arranged. A pressure relief valve is installed on the anaerobic fermentation tank.

[0012] The second feed screw includes a second feed cylinder and a second feed shaft. The second feed cylinder is inclined, and the upper surface of the lower end of the second feed cylinder has a feed port, and the feed port is connected to the first feed cylinder through the second hollow tube. The second feed shaft is installed in the second feed cylinder, and the second feed shaft and the second feed cylinder are coaxially arranged. The lower surface of the upper end of the second feed cylinder has a discharge port.

[0013] Preferably, one end of the first feed shaft, one end of the second feed shaft, one end of the first delivery shaft and one end of the second delivery shaft are respectively fixedly connected to the output end of a driving motor.

[0014] Preferably, a stirring shaft is installed in the anaerobic fermentation tank, one end of the stirring shaft extends from the top of the anaerobic fermentation tank and is fixedly connected to the output end of a stirring motor, and a spiral blade is fixed on the outer wall of the stirring shaft.

[0015] Preferably, the first hollow tube and the second hollow tube are both made of transparent tempered glass material.

[0016] Preferably, the anaerobic fermentation tank is connected to the discharge port of the second feed cylinder through an anaerobic tank feed pipe.

[0017] Preferably, both the first hollow tube and the second hollow tube are provided with height scales.

[0018] Preferably, both the first hollow tube and the second hollow tube are provided with a warehouse wall vibrator.

[0019] Preferably, the first hollow tube and the first feed cylinder, the second feed cylinder, the second hollow tube and the first delivery cylinder, the second delivery cylinder can be connected by welding or by bolts, and sealing gaskets are installed at the connection points to perform sealing. The first hollow tube or the second hollow tube can be spliced ​​in sections, so that the length of the hollow tube can be adjusted more flexibly, which is convenient for the use of different processes and installation and construction in various scenarios.

[0020] Preferably, the anaerobic tank feed pipe is provided with a squeeze-open structure.

[0021] Preferably, the squeeze-open structure is a rubber ring, the outer side of the rubber ring is fixed to the inner wall of the anaerobic tank feed pipe, the inner diameter of the rubber ring is 0 and the inner side of the rubber ring is thinner than the outer side.

[0022] Preferably, the rubber ring is hollow and provided with an air nozzle.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: a continuous dry anaerobic fermentation system of the present invention is provided with an anaerobic fermentation tank for inputting materials by two inclined spiral feed barrels, and the feeding and discharging modules are both connected by hollow tubes between the two sections of the spiral, and a certain height of materials is retained in the hollow tube at any time, so as to meet the requirements of both continuous feeding and sealing, and realize closed continuous discharging. The device of the present invention utilizes the characteristic that the moisture content of the fermented material is about 65% to 88%, and cooperates with the special design in the feeding and discharging modules, so as to realize the (dry) continuous feeding and discharging and synchronous sealing requirements of high solid content waste, realize the stable operation of the dry anaerobic fermentation system, reduce the failure rate, greatly improve the volumetric gas production rate of the dry anaerobic module, increase the large amount of material processing capacity, and reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of a continuous dry anaerobic fermentation system of the present invention;

[0025] Figure 2 for Figure 1 A detailed enlarged schematic diagram of point A in FIG.

[0026] Figure 3 Bit Figure 1 A magnified schematic diagram of the detail at point B of the species.

[0027] In the figure: 1 the first feed screw, 2 the second feed screw, 3 the dry anaerobic reaction module, 4 the first feeding screw, 5 the second feeding screw, 6 the feed hopper, 7 the first feeding barrel, 8 the first feeding shaft, the first hollow tube, 10 the second feeding barrel, 11 the second feeding shaft, 12 the anaerobic tank feeding pipe, 13 the stirring motor, 14 the anaerobic fermentation tank, 15 the spiral blade, 16 the anaerobic tank discharge pipe, 17 the first feeding barrel, 18 the first feeding shaft, 19 the second hollow tube, 20 the second feeding barrel, 21 the second feeding shaft, 22 the pressure relief valve, 23 the silo wall vibrator, 24 the bolt, 25 the sealing gasket, 26 the rubber ring, 27 the air nozzle. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] See also Figure 1-3 The present invention provides a technical solution: a continuous dry anaerobic fermentation system, comprising a first feeding screw 1, a second feeding screw 2, a dry anaerobic reaction module 3, a first feeding screw 4 and a second feeding screw 5.

[0030] The first feed screw 1 includes a first feed barrel 7, a first feed shaft 8, a feed hopper 6 and a first hollow tube 9. The first feed shaft 8 is installed inside the first feed barrel 7. The first feed shaft 8 and the first feed barrel 7 are coaxially arranged. A feed hopper 6 is arranged at the top of one end of the first feed barrel 7, and a vertically arranged first hollow tube 9 is arranged at the bottom of the other end of the first feed barrel 7.

[0031] The second feed screw 2 includes a second feed barrel 10 and a second feed shaft 11. The top of one end of the second feed barrel 10 has a feed port, and the feed port is connected to the first feed barrel 7 through the first hollow tube 9. The second feed shaft 11 is installed inside the second feed barrel 10. The second feed shaft 11 and the second feed barrel 10 are coaxially arranged, and a discharge port is provided on the lower surface of the upper end of the second feed barrel.

[0032] The dry anaerobic reaction module 3 comprises an anaerobic fermentation tank 14 and an anaerobic tank discharge pipe 16 . The top of the anaerobic fermentation tank 14 is connected to the discharge port of the second feed barrel 10 , and the bottom of the anaerobic fermentation tank 14 is connected to an anaerobic tank discharge pipe 16 .

[0033] The first feed screw 4 includes a first feed cylinder 17, a first feed shaft 18 and a second hollow tube 19. The first feed cylinder 17 is inclined. The upper surface of the lower end of the first feed cylinder 17 has a feed port, and the feed port is connected to the anaerobic fermentation tank 14 through the anaerobic tank discharge pipe 16. The first feed shaft 18 is installed inside the first feed cylinder 17. The first feed shaft 18 and the first feed cylinder 17 are coaxially arranged. The upper end of the lower surface of the first feed cylinder 17 is connected to a second hollow tube 19. The second hollow tube 19 is vertically arranged. The anaerobic fermentation tank 14 is equipped with a pressure relief valve 22.

[0034] The second feed screw 5 includes a second feed cylinder 20 and a second feed shaft 21. The second feed cylinder 20 is inclined, and the upper surface of the lower end of the second feed cylinder 20 has a feed port, and the feed port is connected to the first feed cylinder 17 through the second hollow tube 19. The second feed shaft 21 is installed in the second feed cylinder 20. The second feed shaft 21 and the second feed cylinder 20 are coaxially arranged, and the lower surface of the upper end of the second feed cylinder 20 has a discharge port.

[0035] In this embodiment, the first feed barrel 7 and the second feed barrel 10 are inclined, and the second feed barrel 10 is located below the first feed barrel 7. The first hollow tube 9 and the second hollow tube 19 are both vertically arranged. The two ends of the first hollow tube 9 are connected to the first feed barrel 7 and the second feed barrel 10 by flanges. The two ends of the second hollow tube 19 are connected to the first delivery barrel 17 and the second delivery barrel 20 by flanges. The feed hopper 6 is used for users to put materials to be fermented. The materials enter the first feed barrel 7. When the first feed shaft 8 rotates, the materials are conveyed into the first hollow tube 9, and then enter the second feed barrel 10. When the second feed shaft 11 rotates, the materials are conveyed into the anaerobic fermentation tank 14. After the materials are anaerobically fermented in the anaerobic fermentation tank 14, the materials are conveyed from the first delivery barrel 17 to the second hollow tube 19 through the first delivery shaft 18. The materials in the second hollow tube 19 flow into the second delivery barrel 20. When the second delivery shaft 21 rotates, the materials are conveyed to other docking equipment. The materials in the first hollow tube 9, the anaerobic fermentation tank 14 and the second hollow tube 19 can provide closure for the inlet and outlet of the second feed cylinder 10, the first delivery cylinder 17 and the second delivery cylinder 20 to prevent air circulation. In other embodiments, the first feed screw 1, the second feed screw 2, the first delivery screw 4 and the second delivery screw 5 can adopt other forms of conveying devices. And a level measuring instrument for detecting the material height can be set on the top wall of the anaerobic fermentation tank 14, so that the user can obtain the material height in the anaerobic fermentation tank 14 in real time. In other embodiments, 1 to 2 observation windows can be set on the anaerobic fermentation tank 14 for the user to observe the material height.

[0036] Furthermore, one end of the first feed shaft 8, one end of the second feed shaft 11, one end of the first delivery shaft 18 and one end of the second delivery shaft 21 are respectively fixedly connected to an output end of a driving motor.

[0037] In this embodiment, a driving motor is installed at the end of the first feed cylinder 7, the second feed cylinder 10, the first delivery cylinder 17 and the second delivery cylinder 20, and the driving motor is used to drive the first feed shaft 8, the second feed shaft 11, the first delivery shaft 18 and the second delivery shaft 21 to rotate, and the driving motor is connected to an external power supply.

[0038] Furthermore, a stirring shaft is installed in the anaerobic fermentation tank 14 , one end of the stirring shaft extends from the top of the anaerobic fermentation tank 14 and is fixedly connected to the output end of a stirring motor 13 , and a spiral blade 15 is fixed on the outer wall of the stirring shaft.

[0039] In this embodiment, the stirring motor 13 is used to drive the stirring shaft to rotate. The stirring shaft stirs the material in the anaerobic fermentation tank 14 through the spiral blades 15 to improve the fermentation effect. The stirring motor 13 is connected to an external power supply.

[0040] Furthermore, the first hollow tube 9 and the second hollow tube 19 are both made of transparent tempered glass material.

[0041] In this embodiment, the first hollow tube 9 and the second hollow tube 19 made of tempered glass material have a stable structure and good light transmission effect, which is convenient for users to observe the state of the material.

[0042] Furthermore, the anaerobic fermentation tank 14 is connected to the discharge port of the second feeding cylinder 10 through an anaerobic tank feeding pipe 12 , and the material can enter the anaerobic fermentation tank 14 through the anaerobic tank feeding pipe 12 .

[0043] Furthermore, the first hollow tube 9 and the second hollow tube 19 are both provided with height scales, which facilitate the operator to observe the height of the material in the hollow tube, provide convenience for process optimization and research, and various other automatic height detection devices can also be installed, such as infrared height detection devices.

[0044] Furthermore, the first hollow tube 9 and the second hollow tube 19 are both provided with a bin wall vibrator 23, which is an energy-saving general-purpose product with a vibration motor as an excitation source. It relies on high-frequency vibration and impact force to effectively eliminate bridges, arches, blockages, and other phenomena caused by internal friction, deliquescence, electrification, component segregation, etc., so that the material can be discharged smoothly from the bin port, ensuring one of the necessary equipment for stable material supply. The use of the bin material vibrator 23 here can make solid or semi-solid raw materials less likely to hang on the wall and increase the density of the settled material, thereby improving air tightness.

[0045] Furthermore, the first hollow tube 9 and the first feed tube 7, the second feed tube 10, and the second hollow tube 19 and the first delivery tube 17, the second delivery tube 20 can be connected together by welding, or can be connected by bolts 24, and sealing gaskets 25 are installed at the connection points to perform a sealing effect. The first hollow tube 9 or the second hollow tube 19 can be spliced ​​in sections, and such segmented splicing can more flexibly adjust the length of the hollow tube, which is convenient for the use of different processes and installation and construction in various scenarios.

[0046] Furthermore, the anaerobic tank feed pipe 12 is provided with a squeeze-open structure, which can increase the density of the raw material in the second feed screw 2, thereby improving the overall air tightness.

[0047] Furthermore, the squeeze-open structure is a rubber ring 26, the outer side of the rubber ring 26 is fixed to the inner wall of the anaerobic tank feed pipe 12, the inner diameter of the rubber ring 26 is 0, and the inner side of the rubber ring 26 is thinner than the outer side.

[0048] Furthermore, the rubber ring 26 is hollow and provided with an air nozzle 27, so that the discharge pressure in the anaerobic tank feed pipe 12 can be adjusted by inflating the air nozzle 27 of the rubber ring 26, which facilitates the process optimization of air tightness for solid or semi-solid raw materials of different densities.

[0049] Working principle and use process of the present invention: After the present invention is installed, the raw materials are pre-treated first so that the moisture content of the fermented materials reaches about 60% to 80%. The user puts the material to be fermented into the feed hopper 6, and the material enters the first feed barrel 7. When the first feed shaft 8 rotates, the material is transported into the first hollow tube 9, and then enters the second feed barrel 10. When the second feed shaft 11 rotates, the material is transported to the anaerobic fermentation tank 14. After the material is anaerobically fermented in the anaerobic fermentation tank 14, the material is transported from the first feed barrel 17 to the second hollow tube 19 through the first feed shaft 18. The material in the second hollow tube 19 flows into the second feed barrel 20. When the second feed shaft 21 rotates, the material is transported to the device that needs to be processed in the next step. The fermentation system provided by the present invention can carry out anaerobic continuous fermentation, and the material input and output are convenient. During the material transmission process, the first hollow tube 9 and the second hollow tube 19 can be used to check whether there is material to determine whether it is in a sealed state, and then decide whether to start the subsequent material delivery channel. The obtained data can also be used to assist in calculating the parameters required for the process flow. The material in the first hollow tube 9 and the second hollow tube 19 provides a sealing function to reduce material contamination. The pressure relief valve 22 can relieve pressure when the air pressure in the anaerobic fermentation tank 14 is too high, and the device operation is safer.

[0050] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A continuous dry anaerobic fermentation system, characterized in that: It includes a feeding module, a dry anaerobic reaction module and a discharging module; The feeding module comprises a first feeding screw, a first hollow tube and a second feeding screw; The first feeding screw is installed inside the first feeding barrel by the first feeding shaft, the first feeding shaft is coaxially arranged with the first feeding barrel, a feeding hopper is arranged at the top of one end of the first feeding barrel, and the bottom of the other end of the first feeding barrel is connected to the first hollow tube arranged vertically; The second feed screw includes a second feed barrel and a second feed shaft, the second feed barrel has a feed port at the top of one end, the feed port is connected to the first feed barrel through the first hollow tube, the second feed shaft is installed inside the second feed barrel, the second feed shaft and the second feed barrel are coaxially arranged, and the lower surface of the upper end of the second feed barrel has a discharge port; The dry anaerobic reaction module comprises an anaerobic fermentation tank and an anaerobic tank discharge pipe, the top of the anaerobic fermentation tank is connected to the discharge port of the second feed cylinder, and the bottom of the anaerobic fermentation tank is connected to an anaerobic tank discharge pipe; The discharging module comprises a first feeding screw, a second hollow tube and a second feeding screw; The first feeding screw includes a first feeding cylinder and a first feeding shaft. The upper surface of the lower end of the first feeding cylinder has a feeding port, and the feeding port is connected to the anaerobic tank discharge pipe through the anaerobic tank discharge pipe. The first feeding shaft is installed inside the first feeding cylinder. The first feeding shaft and the first feeding cylinder are coaxially arranged. The upper end of the lower surface of the first feeding cylinder is connected to a second hollow tube arranged vertically. A pressure relief valve is installed on the anaerobic fermentation tank; The second feeding screw includes a second feeding cylinder and a second feeding shaft. The upper surface of the lower end of the second feeding cylinder has a feeding port, and the feeding port is connected to the first feeding cylinder through the second hollow tube. The second feeding shaft is installed in the second feeding cylinder, and the second feeding shaft and the second feeding cylinder are coaxially arranged. The lower surface of the upper end of the second feeding cylinder is provided with a discharge port.

2. A continuous dry anaerobic fermentation system according to claim 1, characterized in that: One end of the first feed shaft, one end of the second feed shaft, one end of the first delivery shaft and one end of the second delivery shaft are respectively fixedly connected to an output end of a driving motor.

3. A continuous dry anaerobic fermentation system according to claim 1, characterized in that: A stirring shaft is installed in the anaerobic fermentation tank, one end of the stirring shaft extends from the top of the anaerobic fermentation tank and is fixedly connected to the output end of a stirring motor, and a spiral blade is fixed on the outer wall of the stirring shaft.

4. A continuous dry anaerobic fermentation system according to claim 1, characterized in that: The first hollow tube and the second hollow tube are both made of transparent tempered glass material.

5. A continuous dry anaerobic fermentation system according to claim 1, characterized in that: The anaerobic fermentation tank is connected to the discharge port of the second feeding cylinder through an anaerobic tank feeding pipe.

6. A continuous dry anaerobic fermentation system as claimed in claim 4, characterized in that: The first hollow tube and the second hollow tube are both provided with height scales.

7. A continuous dry anaerobic fermentation system as claimed in claim 4, characterized in that: The first hollow tube and the second hollow tube are both provided with a warehouse wall vibrator.

8. A continuous dry anaerobic fermentation system as claimed in claim 5, characterized in that: The anaerobic tank feed pipe is provided with a squeeze-open structure.

9. A continuous dry anaerobic fermentation system as claimed in claim 8, characterized in that: The squeeze opening structure is a rubber ring, the outer side of the rubber ring is fixed to the inner wall of the anaerobic tank feed pipe, the inner diameter of the rubber ring is 0 and the inner side of the rubber ring is thinner than the outer side. When there is no pressure on the inner side of the rubber ring, it is in a tightened and closed state.

10. A continuous dry anaerobic fermentation system according to claim 9, characterized in that: The rubber ring is in a hollow state and is provided with an air nozzle.

Images