Equipment and method for preparing biogas through anaerobic fermentation of biomass

Abstract

The invention discloses equipment and a method for preparing biogas through anaerobic fermentation of biomass, and belongs to the field of biogas preparation equipment. Comprising a fermentation tank, a stirring assembly is arranged in the middle in the fermentation tank, a spraying assembly is arranged at the upper part in the fermentation tank, a water distribution pipe assembly is arranged at the lower part in the fermentation tank, and a sludge bed is arranged at the bottom of the fermentation tank; the water distribution pipe assembly is arranged above the sludge bed, the water distribution pipe assembly comprises an input pipe, and spraying holes inclining downwards are formed in the two sides of the input pipe; a plurality of biogas collecting covers are arranged at the upper part in the fermentation tank, connecting pipes are arranged at the upper ends of the biogas collecting covers, and integrated pipes are arranged on the connecting pipes. The sludge fermentation device has the beneficial effects that in the sludge fermentation process, the motor drives the scraping plate to rotate, and the scraping plate can scrape up sludge attached to a sludge bed, so that sludge accumulation is prevented. The water flow impacts the surface of the sludge bed through the spray holes which are inclined downwards, so that the effect of impacting the sludge can be achieved, and the effect of removing the sludge on the surface of the sludge bed is improved.

Description

Technical Field

[0001] The invention relates to equipment and method for preparing biogas by anaerobic fermentation of biomass, belonging to the field of biogas preparation equipment. Background Art

[0002] In the process of anaerobic fermentation to produce biogas, the traditional fermentation tank design often has some limitations. These limitations are that when biomass produces biogas, due to the operation of the stirring device in the fermentation tank, many bubbles appear on the surface of the biomass liquid. Excessive accumulation of these bubbles will affect the normal rise of biogas, resulting in low efficiency of biogas collection.

[0003] Therefore, a common design is to use a spray system on the top of the fermentation tank. This spray system relies on the sprayed water droplets to hit the foam, which can eliminate the bubbles on the liquid surface. However, since the direction of the sprayed water droplets is fixed, it is impossible to accurately defoam the foam in different positions, so the foam will still exist, which will affect the production and stability of biogas.

[0004] Some designs have tried to improve the mixing effect inside the fermenter by adding a stirrer, but this mechanical stirring method has high energy consumption and low stirring efficiency, and the biomass cannot react quickly enough to produce biogas, resulting in increased costs. At the same time, the presence of a mechanical stirrer also limits the volume utilization of the fermenter because sufficient space needs to be left for the stirrer.

[0005] In summary, the traditional anaerobic fermentation technology for producing biogas has many shortcomings in the design of the fermentation tank, such as uneven mixing, difficult temperature control, complex maintenance and high energy consumption, which limit the efficiency and economic benefits of biogas production. Therefore, the development of a new anaerobic fermentation device for producing biogas to improve fermentation efficiency, reduce energy consumption and simplify operation has become an urgent need for the development of the industry. Summary of the invention

[0006] The purpose of the present invention is to provide a device and method for producing biogas by anaerobic fermentation of biomass, which can effectively solve the above-mentioned problems.

[0007] In order to solve the above technical problems, the present invention is achieved through the following technical solutions: It comprises a fermentation tank, wherein a stirring assembly is arranged in the middle part of the fermentation tank, a spray assembly is arranged in the upper part of the fermentation tank, a water distribution pipe assembly is arranged in the lower part of the fermentation tank, and a sludge bed is arranged at the bottom of the fermentation tank; the water distribution pipe assembly is arranged above the sludge bed, the water distribution pipe assembly comprises an input pipe, and spray holes inclined downward are arranged on both sides of the input pipe; Wherein, a scraper device is arranged between the sludge bed and the water distribution pipe assembly, the scraper device comprises a rotating sleeve, the rotating sleeve has a plurality of scrapers in a circular array, and the rotating sleeve is driven by a motor; The water distribution pipe assembly also includes an integrated ring pipe, the input pipes are arranged in a circular array on the integrated ring pipe, and the number of the input pipes is the same as the number of the scrapers.

[0008] Further: the stirring assembly includes a first stirring shaft, a second stirring shaft and a speed regulating device arranged between the first stirring shaft and the second stirring shaft; The first stirring shaft is provided with a first stirring structure, the first stirring structure comprises a first mounting sleeve, and the first mounting sleeve has four first stirring blades evenly distributed on its circumference; The second stirring shaft is provided with a second stirring structure, the second stirring structure comprises a second mounting sleeve, and the second mounting sleeve is provided with four second stirring blades evenly distributed on the circumference; the first stirring blade is larger than the second stirring blade.

[0009] Further: the speed regulating device comprises a mounting shell, a driven helical gear ring is arranged in the mounting shell, three driven helical gears are meshed in the driven helical gear ring, and driving helical gears are meshed between the driven helical gears; A bearing is arranged in the middle of the driven helical gear, an output rod is fixed in the bearing, a triangular plate is arranged on the output rod, and an output shaft is arranged in the middle of the triangular plate; The first stirring shaft is key-connected to the driving bevel gear, and the second stirring shaft is connected to the output shaft via a first coupling.

[0010] Further: the spray assembly includes a hanging pipe, the lower end of the hanging pipe is rotatably connected to a liquid supply box, the side circumference of the liquid supply box is evenly distributed with liquid supply pipes, the lower end of the liquid supply pipe is connected to a liquid supply ring, the side circumference of the liquid supply ring is evenly distributed with liquid supply rods, and the lower end of the liquid supply rod is provided with an atomizing nozzle.

[0011] Furthermore: a water pump is arranged at the upper end of the hanging pipe, and the water pump is connected to a water tank.

[0012] Further: the spray assembly is connected to the second stirring shaft through a steering adjustment assembly and receives the rotational force from the second stirring shaft; the steering adjustment assembly includes a connecting shaft connected to the lower end of the liquid supply tank, an adjustment box is arranged below the connecting shaft, a forward bevel gear is arranged at the bottom of the adjustment box, a reverse bevel gear is arranged at the top of the adjustment box, a matching bevel gear is arranged on the inner side of the adjustment box, and the forward bevel gear and the reverse bevel gear are meshed with the matching bevel gear; The forward helical gear is key-connected to the second stirring shaft, and the reverse helical gear is key-connected to a connecting shaft.

[0013] Furthermore: a plurality of biogas collecting hoods are arranged at the upper part of the fermentation tank, a connecting pipe is arranged at the upper end of the biogas collecting hood, and an integrated pipe is arranged on the connecting pipe.

[0014] Furthermore: a baffle is also provided in the fermentation tank, a through hole is provided in the baffle, the baffle is arranged below the biogas collection hood, the through hole corresponds to the upper and lower positions of the biogas collection hood, and the diameter of the through hole is equal to the diameter of the biogas collection hood at the hood opening.

[0015] A method for producing biogas by anaerobic fermentation of biomass; the method comprises: S1. Sludge pretreatment, preliminary screening, homogenization and concentration of sludge to reduce solid content; S2. diluting the sludge, mixing the sludge with water to form diluted sludge water; S2. Anaerobic digestion reaction: sludge water is input into the fermentation tank through the water distribution pipe assembly, passes through the stirring shaft of the stirring assembly, and is mixed with the reaction zone in the fermentation tank to produce biogas.

[0016] The beneficial effects are: Compared with the prior art, this technical solution mainly solves the following problems: 1. During the sludge fermentation process, turn on the motor, and the motor will drive the scraper to rotate through the rotating sleeve. The scraper will scrape up the sludge attached to the sludge bed to prevent sludge accumulation.

[0017] 2. The downward-slanting spray holes allow the water flow to impact the surface of the sludge bed, which can impact the sludge and improve the effect of removing sludge on the surface of the sludge bed.

[0018] 3. The stirring efficiency can be improved by setting the stirring structure with different speeds.

[0019] 4. The entire spray assembly is also set to rotate, and the direction of rotation is opposite to the direction of stirring, so that the water droplets will be thrown in an arc when moving, increasing the travel of the moving trajectory and increasing the contact time with the foam, thereby achieving the purpose of improving the defoaming effect.

[0020] 5. In order to remove the sludge accumulated at the edge of the bottom of the fermentation tank, this device is provided with a mounting ring at the edge of the bottom of the fermentation tank. The mounting ring has a circular array of output holes on the upper end surface. Water flows out from the output holes to impact the accumulated sludge, which can accelerate the mixing of mud and liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and the accompanying drawings.

[0022] Figure 1It is a structural schematic diagram of the present invention; Figure 2 This is a schematic diagram of the bottom structure of the fermentation tank of the present invention; Figure 3 It is a parts diagram of the scraper device of the present invention; Figure 4 It is a parts diagram of the water distribution pipe assembly of the present invention; Figure 5 is a cross-sectional view of an input pipe of the present invention; Figure 6 It is the parts diagram of the speed regulating device of the present invention; Figure 7 It is a parts diagram of the spray assembly of the present invention; Figure 8 It is a front view of the spray assembly of the present invention; Fig. 9 It is the parts diagram of the steering adjustment assembly of the present invention; Fig.10 It is a fluid simulation front view when the stirring assembly of the present invention is working; Fig.11 A fluid simulation top view of the stirring assembly of the present invention when it is working; Fig.12 This is a fluid simulation state diagram when the first stirring structure of the present invention is working; Fig.13 This is a diagram of the installation position of the installation ring in the present invention.

[0023] Description of reference numerals: 1. Fermentation tank; 2. Stirring assembly; 21. First stirring shaft; 22. Second stirring shaft; 23. Speed ​​regulating device; 231. Mounting shell; 232. Driven helical gear ring; 233. Driven helical gear; 234. Driving helical gear; 235. Bearing; 236. Output rod; 237. Triangular plate; 238. Output shaft; 24. First stirring structure; 241. First mounting sleeve; 242. First stirring blade; 25. Second stirring structure; 251. Second mounting sleeve; 252. Second stirring blade; 3. Spraying assembly; 31. Hanging pipe; 32. Liquid supply box; 33. Liquid supply pipe; 34. Liquid supply ring; 35. Liquid supply rod; 36. Atomizing nozzle ; 37. Connecting rod; 38. Water pump; 4. Water distribution pipe assembly; 41. Input pipe; 42. Spray hole; 43. Integrated ring pipe; 44. First water inlet pipe; 45. Arc pipe; 5. Sludge bed; 6. Scraper device; 61. Rotating sleeve; 62. Scraper; 7. Motor; 8. First coupling; 9. Steering adjustment assembly; 91. Connecting shaft; 92. Adjustment box; 93. Forward bevel gear; 94. Reverse bevel gear; 95. Matching bevel gear; 10. Biogas collection hood; 11. Connecting pipe; 12. Integrated pipe; 13. Baffle; 14. Mounting ring; 15. Output hole; 16. Second water inlet pipe; 17. First support rod; 18. Second support rod. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0025] It should be noted that, in the description of the present invention, unless otherwise specified, “plurality” means two or more than two; the orientations or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “inside”, “outside”, “front end”, “rear end”, “head” and “tail” are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] Furthermore, the terms “first,” “second,” “third,” etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

[0027] Meanwhile, in the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] See also Figure 1-13 This is an embodiment of a device and method for producing biogas by anaerobic fermentation of biomass according to the present invention. See also Figure 1 , including a fermentation tank 1, a stirring assembly 2 is arranged in the middle part of the fermentation tank 1, a spray assembly 3 is arranged in the upper part of the fermentation tank 1, a water distribution pipe assembly 4 is arranged in the lower part of the fermentation tank 1, and a sludge bed 5 is arranged at the bottom of the fermentation tank 1; the water distribution pipe assembly 4 is arranged above the sludge bed 5, the water distribution pipe assembly 4 includes an input pipe 41, and spray holes 42 inclined downward are arranged on both sides of the input pipe 41; a plurality of biogas collecting hoods 10 are arranged in the upper part of the fermentation tank 1, a connecting pipe 11 is arranged at the upper end of the biogas collecting hood 10, and an integrated pipe 12 is arranged on the connecting pipe 11.

[0029] The fermentation tank 1 in the present device is filled with water, and sludge water is flushed into the fermentation tank 1 from the water distribution pipe assembly 4 until the liquid level rises to a predetermined height; at this time, the heating plate on the periphery of the fermentation tank 1 is turned on to heat the inside of the fermentation tank 1 to 37°C, so that the sludge is decomposed. As the sludge decomposes, the sludge will produce biogas, and the generated biogas will enter the biogas collection hood 10, enter the integrated pipe 12 through the connecting pipe 11, and finally be output from the integrated pipe 12.

[0030] See also Figure 2 , Figure 3 , Figure 4 ; In the present device, during the fermentation process in the entire fermentation tank 1, the sludge will gradually settle and finally settle on the sludge bed 5, which will actually reduce the fermentation speed of the sludge. Therefore, in order to prevent the sludge from settling on the sludge bed 5, the present device is provided with a scraper device 6 between the sludge bed 5 and the water distribution pipe assembly 4. The scraper device 6 includes a rotating sleeve 61, and the rotating sleeve 61 has a plurality of scrapers 62 in a circumferential array. The rotating sleeve 61 is driven by a motor 7; During the sludge fermentation process, the motor 7 is turned on, and the motor 7 drives the scraper 62 to rotate through the rotating sleeve 61, and the scraper 62 scrapes the sludge attached to the sludge bed 5 to prevent the sludge from accumulating; See also Figure 5 At the same time, in this device, as the sludge ferments to produce biogas, the level in the entire fermentation tank 1 will gradually drop, so it is necessary to add sludge water from time to time. When adding sludge water, high-pressure sludge water is sprayed out from the spray hole 42 of the input pipe 41; and the downwardly inclined spray hole 42 allows the water flow to impact the surface of the sludge bed 5, which can play a role in impacting the sludge and improve the effect of removing the sludge on the surface of the sludge bed 5.

[0031] The water distribution pipe assembly 4 of the device further includes an integrated annular pipe 43 , on which the input pipes 41 are arranged in a circumferential array, and the number of the input pipes 41 is the same as the number of the scrapers 62 .

[0032] The function of the integrated ring pipe 43 in the device is to set a plurality of input pipes 41, so as to facilitate the rapid and uniform input of sludge water into the space in the fermentation tank 1; the number of the input pipes 41 is the same as the number of the scrapers 62 mainly because, when the scrapers 62 are not rotating, it is convenient for the sludge water to impact the sludge on the sludge bed 5 through the spray holes 42 of the input pipes 41; One of the input pipes 41 in the device is connected to a first water inlet pipe 44 . The function of the first water inlet pipe 44 is to provide sludge water to the input pipe 41 , and then the sludge water is distributed to all the input pipes 41 through the integration of the integrated ring pipe 43 .

[0033] The end of the input pipe 41 in the present device is also provided with a plurality of arc tubes 45, and the lower end of the arc tube 45 is also provided with a spray hole 42 which is the same as the lower end of the input pipe 41; since all the input pipes 41 are in a state of radiating outward from the center, the distance between the ends of two adjacent input pipes 41 will gradually increase with the length of the input pipe 41. In order to improve the cleaning efficiency of the input pipe 41 for the sludge bed 5, a plurality of arc tubes 45 are provided at the end of the input pipe 41, the purpose of which is to increase the area of ​​the spray hole 42 covering the sludge bed 5.

[0034] Specifically, after the fermentation tank 1 is used for the first time, sludge will be attached to the sludge bed 5, and this sludge is not easy to clean; therefore, when the fermentation tank 1 is used for the second time, sludge water needs to be added to the entire empty fermentation tank 1. At this time, the sludge water passes through the spray hole 42 in the input pipe 41, and the sludge water will be sprayed onto the sludge on the sludge bed 5, which can play the role of cleaning the sludge on the sludge bed 5 while adding sludge water; there is no need to set up an additional cleaning device for the sludge bed 5, which can reduce costs; At the same time, in order to facilitate cleaning, the position of the scraper 62 can be matched with the upper and lower positions of the input pipe 41. Specifically, the fan-shaped area formed by two adjacent scrapers 62 can be placed below the input pipe 41. At this time, the scraper 62 is equivalent to a partition wall, which divides the entire sludge bed 5 into fan-shaped areas of the same area, and there is an input pipe 41 above each fan-shaped area. With this arrangement, the sludge on the surface of the sludge bed 5 can be removed more conveniently.

[0035] See also Figure 4 One of the input pipes 14 in the device is connected to a first water inlet pipe 44, and the first water inlet pipe 44 is connected to a water pump. Since the entire water distribution pipe assembly 4 is fixed as a whole in the fermentation tank 1, the entire water distribution pipe assembly 4 can be supplied with water through the first water inlet pipe 44.

[0036] In order to prevent the sludge from settling on the sludge bed 5, a stirring assembly 2 is provided in the present device; the stirring assembly 2 can keep the liquid in the entire fermentation tank 1 in motion by stirring at a slow speed, thereby reducing the settling speed of the sludge; See also Figure 1 The stirring assembly 2 in the device includes a first stirring shaft 21, a second stirring shaft 22 and a speed regulating device 23 arranged between the first stirring shaft 21 and the second stirring shaft 22; a first stirring structure 24 is arranged on the first stirring shaft 21, and the first stirring structure 24 includes a first mounting sleeve 241, and four first stirring blades 242 are evenly distributed on the circumference of the first mounting sleeve 241; a second stirring structure 25 is arranged on the second stirring shaft 22, and the second stirring structure 25 includes a second mounting sleeve 251, and four second stirring blades 252 are evenly distributed on the circumference of the second mounting sleeve 251; the size of the first stirring blade 242 is larger than the second stirring blade 252.

[0037] See also Figure 6 The first stirring structure 24 and the second stirring structure 25 are roughly similar in overall shape, and are also the most suitable structures for liquid stirring. However, the present device does not require very high-speed stirring, so when stirring at a low speed, this stirring structure will form a layered tumbling vortex during stirring, and this tumbling vortex is that the liquid rolls from the inner wall of the fermentation tank 1 toward the stirring axis direction; that is to say, after the first stirring structure 24 stirs, the formed three-dimensional tumbling vortex will stay at the lower part of the fermentation tank 1, and only a few sludge particles and water molecules are thrown to the upper layer; and a second stirring structure 25 of relatively small size is provided, and the second stirring structure 25 will also form a three-dimensional tumbling vortex, and the lower part of the three-dimensional tumbling vortex located above overlaps with the upper part of the three-dimensional tumbling vortex located below, so that the sludge particles and water molecules can be smoothly transferred to the upper half of the fermentation tank 1, thereby improving the stirring efficiency.

[0038] The formed stratified tumbling vortex is a turbulent two-phase flow that is common knowledge in the field; however, in actual use, since the device is used to collect biogas in sludge, the main function of the first stirring structure 24 is to mix the sludge and water and produce biogas after sufficient fermentation, while the main function of the second stirring structure 25 is to smoothly separate the generated biogas from the mud liquid and make it rise and finally float to the liquid surface, and the auxiliary function is to strengthen the mixing of sludge and water; However, the stirring speeds of the first stirring structure 24 and the second stirring structure 25 are the same. Although the mud and liquid can be fully mixed, when the biogas rises later, the biogas bubbles are easily broken up by the high-speed rotating second stirring structure 25 and become smaller bubbles. These bubbles will be reabsorbed by the mud and liquid, reducing the production efficiency of biogas. Therefore, in order to facilitate the production and precipitation of biogas, it is necessary to reduce the stirring speed of the second stirring structure 25 to prevent the generated biogas from being absorbed by the mud and liquid again.

[0039] See also Fig.10 , Fig.11 It is a simulation diagram of the stirring of the device; the speed regulating device 23 provided in the device has such a function, which can make the speed of the second stirring structure 25 smaller than the speed of the first stirring structure 24; while achieving full mixing of the mud and liquid to produce biogas, the biogas bubbles will not be broken too much, so that the generated biogas can float to the liquid surface smoothly and enter the biogas collection hood 10.

[0040] At the same time, when there is no speed regulating device 23, the stirring speeds of the first stirring structure 24 and the second stirring structure 25 are the same. In actual use, the formed water flow is relatively stable, and the liquid located on the side wall of the fermentation tank 1 is difficult to be integrated into the stirred water flow, and the mixing effect of the sludge particles and water molecules is not very high. After the speed regulating device 23 is set, the speed of the first stirring structure 24 will be greater than that of the second stirring structure 25. This design is mainly based on the consideration that most of the sludge is located below the fermentation tank 1, so a larger first stirring blade 242 is designed to provide a larger range of turbulence; the second stirring structure 25 has a smaller second stirring blade 252, which is mainly used to facilitate the transportation of biogas from the liquid.

[0041] See also Fig.12 This is a stirring simulation diagram when only the first stirring structure 24 is working. According to the simulation diagram, when the first stirring structure 24 is stirring, a lot of sludge will be concentrated at the edge of the bottom of the fermentation tank 1. This part of the sludge will continue to accumulate at the edge under the action of the water flow, affecting the subsequent fermentation. See also Fig.13 In order to remove the sludge accumulated at the edge of the bottom of the fermenter 1, the device is provided with a mounting ring 14 at the edge of the bottom of the fermenter 1, and the mounting ring 14 has an output hole 15 in a circular array on the upper end surface; and a second water inlet pipe 16 is connected to the mounting ring 14, and the second water inlet pipe 16 is used to provide impact water flow for the mounting ring 14.

[0042] When the sludge is forced to gather at the bottom edge of the fermentation tank 1 under the influence of the first stirring structure 24 , a fluid such as liquid or gas is introduced into the mounting ring 14 , and the fluid is discharged from the output hole 15 , which can blow away the sludge at the bottom and add it to the turbulent flow formed by the first stirring structure 24 .

[0043] The speed regulating device 23 in the present device comprises a mounting shell 231, in which a driven helical gear ring 232 is arranged, in which three driven helical gears 233 are meshed, and a driving helical gear 234 is meshed between the driven helical gears 233; a bearing 235 is arranged in the middle of the driven helical gears 233, in which an output rod 236 is fixed, a triangular plate 237 is arranged on the output rod 236, and an output shaft 238 is arranged in the middle of the triangular plate 237; the first stirring shaft 21 is key-connected with the driving helical gear 234, and the second stirring shaft 22 is connected with the output shaft 238 via a first coupling 8.

[0044] When the first stirring shaft 21 rotates, it drives the active bevel gear 234 to rotate, and the active bevel gear 234 drives the driven bevel gear 233 meshing therewith to rotate, and at the same time the driven bevel gear 233 drives the driven bevel gear ring 232 to rotate, and under the restriction of the driven bevel gear ring 232, the three driven bevel gears 233 move slowly in a circle in the same direction; Then, a bearing 235 is set in the driven bevel gear 233, and an output rod 236 is fixed on the bearing 235. The three output rods 236 are set on a triangular plate 237. The three driven bevel gears 233 make synchronous circular motions, which will drive the triangular plate 237 to rotate, so as to achieve the purpose of the triangular plate 237 driving the output shaft 238 to rotate; at this time, the rotation speed of the output shaft 238 will be lower than the rotation speed of the first stirring shaft 21, and the output shaft 238 is connected to the second stirring shaft 22 through the first coupling 8, which is equivalent to the rotation speed of the second stirring shaft 22 being lower than the rotation speed of the first stirring shaft 21; in this way, the coaxial but different speed setting of the first stirring structure 24 and the second stirring structure 25 is completed.

[0045] See also Figure 1 , Figure 7 , Figure 8 The spray assembly 3 in the device includes a hanging pipe 31, the lower end of the hanging pipe 31 is rotatably connected to a liquid supply box 32, the side circumference of the liquid supply box 32 is evenly distributed with liquid supply pipes 33, the lower end of the liquid supply pipe 33 is connected to a liquid supply ring 34, the side circumference of the liquid supply ring 34 is evenly distributed with liquid supply rods 35, and the lower end of the liquid supply rod 35 is provided with an atomizing nozzle 36; the upper end of the hanging pipe 31 is provided with a water pump 38, and the water pump 38 is connected to a water tank.

[0046] Since a large number of bubbles will be generated during the reaction of sludge water, these bubbles will affect the rise of biogas, so a spray assembly 3 is required to provide spray water to defoam the foam above the liquid surface; when in use, the water pump 38 pumps water and delivers it to the liquid supply pipe 33 through the liquid supply tank 32, and then the liquid supply pipe 33 delivers it to the liquid supply rod 35 through the liquid supply ring 34, and finally sprays it out from the atomizing nozzle 36 under the liquid supply rod 35, and the sprayed water droplets hit the foam to complete the defoaming.

[0047] The present device takes into account that when the stirring component 2 is working, it will not only provide a three-dimensional rolling vortex, but also make the liquid form a three-dimensional conical vortex. At this time, the liquid in the fermentation tank 1 is generally a three-dimensional conical vortex, and there are two layered rolling vortices in the conical vortex; the direction of the conical vortex is the stirring direction, and it is also the direction of foam movement; See also Fig. 9 In order to increase the probability of collision between water droplets and foam, the entire spray assembly 3 in this device is also set to rotate, and the direction of rotation is opposite to the direction of stirring, so that the water droplets will be thrown in an arc when moving, increasing the travel of the moving trajectory and increasing the contact time with the foam, thereby achieving the purpose of improving the defoaming effect.

[0048] The specific spray component 3 is connected to the second stirring shaft 22 through the steering adjustment component 9, and receives the rotational force from the second stirring shaft 22; the steering adjustment component 9 includes a connecting shaft 91 connected to the lower end of the liquid supply box 32, and an adjustment box 92 is arranged below the connecting shaft 91, a forward bevel gear 93 is arranged at the bottom of the adjusting box 92, a reverse bevel gear 94 is arranged at the top of the adjusting box 92, and a matching bevel gear 95 is arranged on the inner side of the adjusting box 92, and the forward bevel gear 93 and the reverse bevel gear 94 are meshed with the matching bevel gear 95; the forward bevel gear 93 is key-connected to the second stirring shaft 22, and the connecting shaft 91 is key-connected to the reverse bevel gear 94.

[0049] The second stirring shaft 22 outputs power to the forward bevel gear 93, and the forward bevel gear 93 rotates, thereby driving the matching bevel gear 95; then the matching bevel gear 95 drives the reverse bevel gear 94 to rotate, and at this time the direction of the reverse bevel gear 94 is opposite to the direction of the forward bevel gear 93, and then the reverse bevel gear 94 drives the connecting shaft 91 to rotate, and the connecting shaft 91 drives the liquid supply box 32 to rotate; the liquid supply box 32 drives the liquid supply ring 34 to rotate through the connecting rod 37, and the liquid supply ring 34 drives the liquid supply rod 35 and the atomizing nozzle 36 to rotate; The hanging pipe 31 does not need to rotate because it is needed to hang up the entire spray assembly 3 and provide liquid to the liquid supply box 32.

[0050] A baffle 13 is also provided in the fermentation tank 1, and a through hole is provided in the baffle 13. The baffle 13 is arranged below the biogas collecting hood 10, and the through hole corresponds to the upper and lower positions of the biogas collecting hood 10, and the diameter of the through hole is equal to the diameter of the biogas collecting hood 10 at the hood opening.

[0051] The function of the biogas collecting hood 10 in this device is to collect biogas. In order to facilitate the collection of biogas, a baffle 13 is provided in this device. The function of the baffle is to block the rising direction of the biogas, and then a through hole is opened to connect with the biogas collecting hood 10, so that the biogas will enter the biogas collecting hood 10, which is very convenient and easy.

[0052] In this device, since the stirring component does not need to stir very quickly, the rotational force output by the motor 7 drives the scraper device 6, which then drives the stirring component 2, and then drives the spray component 3; a single-motor multi-drive method is implemented, which can save costs.

[0053] The device is also provided with a first support rod 17 and a second support rod 18; the first support rod 17 is used to facilitate fixing the adjustment box 92 inside the fermentation tank 1; the second support rod 18 is used to fix the speed adjustment device 23 inside the fermentation tank 1.

[0054] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A device for producing biogas by anaerobic fermentation of biomass, characterized in that: The invention comprises a fermentation tank (1), wherein a stirring assembly (2) is arranged in the middle part of the fermentation tank (1), a spray assembly (3) is arranged in the upper part of the fermentation tank (1), a water distribution pipe assembly (4) is arranged in the lower part of the fermentation tank (1), and a sludge bed (5) is arranged at the bottom of the fermentation tank (1); the water distribution pipe assembly (4) is arranged above the sludge bed (5), the water distribution pipe assembly (4) comprises an input pipe (41), and spray holes (42) inclined downward are arranged on both sides of the input pipe (41); wherein a scraper device (6) is arranged between the sludge bed (5) and the water distribution pipe assembly (4), the scraper device (6) comprises a rotating sleeve (61), the rotating sleeve (61) has a plurality of scrapers (62) arranged in a circular array, and the rotating sleeve (61) is driven by a motor (7); The water distribution pipe assembly (4) further comprises an integrated annular pipe (43), the input pipes (41) are arranged in a circular array on the integrated annular pipe (43), and the number of the input pipes (41) is the same as the number of the scrapers (62).

2. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 1, characterized in that: The stirring assembly (2) comprises a first stirring shaft (21), a second stirring shaft (22) and a speed regulating device (23) arranged between the first stirring shaft (21) and the second stirring shaft (22); a first stirring structure (24) is arranged on the first stirring shaft (21), the first stirring structure (24) comprises a first mounting sleeve (241), and four first stirring blades (242) are evenly distributed on the circumference of the first mounting sleeve (241); a second stirring structure (25) is arranged on the second stirring shaft (22), the second stirring structure (25) comprises a second mounting sleeve (251), and four second stirring blades (252) are evenly distributed on the circumference of the second mounting sleeve (251); the first stirring blade (242) is larger than the second stirring blade (252).

3. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 2, characterized in that: The speed regulating device (23) comprises a mounting shell (231), wherein a driven helical gear ring (232) is arranged in the mounting shell (231), wherein three driven helical gears (233) are meshed in the driven helical gear ring (232), and a driving helical gear (234) is meshed between the driven helical gears (233); a bearing (235) is arranged in the middle of the driven helical gears (233), an output rod (236) is fixed in the bearing (235), a triangular plate (237) is arranged on the output rod (236), and an output shaft (238) is arranged in the middle of the triangular plate (237); the first stirring shaft (21) and the driving helical gear (234) are key-connected, and the second stirring shaft (22) and the output shaft (238) are connected via a first coupling (8).

4. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 3, characterized in that: The spray assembly (3) comprises a hanging pipe (31), the lower end of the hanging pipe (31) being rotatably connected to a liquid supply box (32), liquid supply pipes (33) being evenly distributed on the circumference of the side surface of the liquid supply box (32), the lower end of the liquid supply pipe (33) being connected to a liquid supply ring (34), liquid supply rods (35) being evenly distributed on the circumference of the side surface of the liquid supply ring (34), and an atomizing nozzle (36) being provided at the lower end of the liquid supply rod (35).

5. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 4, characterized in that: A water pump (38) is provided at the upper end of the hanging pipe (31), and the water pump (38) is connected to a water tank.

6. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 5, characterized in that: The spray assembly (3) is connected to the second stirring shaft (22) through a steering adjustment assembly (9) and receives a rotational force from the second stirring shaft (22); the steering adjustment assembly (9) comprises a connecting shaft (91) connected to the lower end of the liquid supply box (32); an adjustment box (92) is arranged below the connecting shaft (91); a forward bevel gear (93) is arranged at the bottom of the adjustment box (92); a reverse bevel gear (94) is arranged at the top of the adjustment box (92); a matching bevel gear (95) is arranged on the inner side surface of the adjustment box (92); the forward bevel gear (93) and the reverse bevel gear (94) are meshed with the matching bevel gear (95); the forward bevel gear (93) is key-connected to the second stirring shaft (22); and the connecting shaft (91) is key-connected to the reverse bevel gear (94).

7. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 1, characterized in that: A plurality of biogas collecting hoods (10) are arranged at the upper part of the fermentation tank (1), a connecting pipe (11) is arranged at the upper end of the biogas collecting hood (10), and an integrated pipe (12) is arranged on the connecting pipe (11).

8. The equipment for producing biogas by anaerobic fermentation of biomass according to claim 7, characterized in that: A baffle (13) is further provided in the fermentation tank (1), wherein a through hole is provided in the baffle (13), and the baffle (13) is provided below the biogas collection hood (10), wherein the through hole corresponds to the upper and lower positions of the biogas collection hood (10), and the diameter of the through hole is equal to the diameter of the opening of the biogas collection hood (10).

9. A method for producing biogas by anaerobic fermentation of biomass, characterized in that: The method is based on the device for producing biogas by anaerobic fermentation of biomass as described in any one of claims 1 to 8 above; the method comprises: S1. sludge pretreatment, preliminary screening, homogenization and concentration of the sludge to reduce the solid content; S2. dilution treatment of the sludge, mixing the sludge with water to form diluted sludge water; S2. anaerobic digestion reaction, the sludge water is input into the fermentation tank (1) through the water distribution pipe assembly (4), passes through the stirring shaft of the stirring assembly (2), and is mixed with the reaction zone in the fermentation tank (1) to produce biogas.

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