Anaerobic fermentation residue solid-liquid separation equipment based on dissolved air flotation technology

Abstract

The utility model discloses anaerobic fermentation residue solid-liquid separation equipment based on a dissolved air flotation technology, which relates to the technical field of anaerobic fermentation residue utilization and treatment, and comprises a spiral extrusion device and an air flotation device, the spiral extrusion device is used for carrying out solid-liquid separation on anaerobic fermentation residues, and the air flotation device is used for carrying out air flotation on the anaerobic fermentation residues. A bubble generating device is arranged in an air flotation tank of the air flotation device and is used for generating bubbles, and a water outlet of the spiral extrusion device is communicated with a water inlet of the air flotation device, so that liquid in anaerobic fermentation residues is mixed with the bubbles, and the bubbles are mixed with the liquid in the anaerobic fermentation residues; air bubbles are arranged in the air floatation tank, the air bubbles are attached to suspended matter particles in the liquid to drive the suspended matter particles to float upwards, and a slag scraper is arranged above the air floatation tank and used for scraping the suspended matter particles in the air floatation tank into a slag discharging tank of the air floatation tank. According to the utility model, the solid-liquid separation rate of biogas slurry and biogas residue is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of anaerobic fermentation residue utilization and treatment, in particular to anaerobic fermentation residue solid-liquid separation equipment based on dissolved air flotation technology. Background Art

[0002] Anaerobic fermentation technology can convert agricultural waste such as straw and livestock and poultry manure into biogas, biogas residue, biogas liquid and other substances through microbial metabolic decomposition, which is conducive to promoting the recycling of agricultural waste. The biogas produced can be used as a clean energy to replace fossil energy. The biogas residue contains relatively rich organic matter and trace elements, which can be used as organic fertilizer to replace chemical fertilizer and protect the environment.

[0003] The most commonly used wet anaerobic fermentation technology currently produces a large amount of biogas slurry, which is mainly used for returning to the field and developing liquid fertilizers. Since the biogas slurry produced by fermentation contains a certain amount of biogas residue, it cannot be used directly, so the biogas slurry needs to be separated into solids and liquids. However, the commonly used biogas slurry and biogas residue solid-liquid separation device cannot meet the solid removal requirements for direct return of biogas slurry to the field. Utility Model Content

[0004] The utility model aims to provide a solid-liquid separation device for anaerobic fermentation residues based on dissolved air flotation technology, thereby improving the solid-liquid separation rate of biogas slurry and biogas residue.

[0005] To achieve the above purpose, the utility model provides the following solutions:

[0006] The utility model provides a solid-liquid separation device for anaerobic fermentation residue based on dissolved air flotation technology, comprising a spiral extrusion device and an air flotation device, wherein the spiral extrusion device is used for solid-liquid separation of anaerobic fermentation residue, a bubble generating device is arranged in an air flotation tank of the air flotation device, the bubble generating device is used for generating bubbles, a water outlet of the spiral extrusion device is connected with a water inlet of the air flotation device, so that the liquid in the anaerobic fermentation residue is mixed with the bubbles, and the bubbles are attached to the suspended particles in the liquid to drive the suspended particles to float, a slag scraper is arranged above the air flotation tank, and the slag scraper is used for scraping the suspended particles in the air flotation tank into a slag discharge tank of the air flotation tank.

[0007] Preferably, the spiral extrusion device includes a motor, a reducer and a core shaft, a feed port is arranged at the upper portion of the spiral extrusion device, the feed port is close to one end of the spiral extrusion device, the feed port is funnel-shaped, the water outlet is arranged at the lower portion of the spiral extrusion device, and a slag outlet is arranged at the other end of the spiral extrusion device, the motor drives the core shaft to rotate through the reducer, and the core shaft drives the extrusion spiral structure outside the core shaft to rotate, the anaerobic fermentation residue enters from the feed port, and after being extruded by the extrusion spiral structure, the liquid flows out through the water outlet, and the solid is discharged through the slag outlet.

[0008] Preferably, the pitch of the extrusion spiral structure gradually decreases from one end of the spiral extrusion device to the other end of the spiral extrusion device.

[0009] Preferably, a first connecting pipe and a second connecting pipe are arranged between the water outlet of the spiral extrusion device and the water inlet of the flotation device, one end of the first connecting pipe is detachably connected to the water outlet of the spiral extrusion device, a filter structure is arranged between the other end of the first connecting pipe and one end of the second connecting pipe, and the other end of the second connecting pipe is detachably connected to the water inlet of the flotation device.

[0010] Preferably, the filter structure is a spherical filter, a third connecting pipeline is arranged between the other end of the first connecting pipeline and one end of the second connecting pipeline, the two ends of the third connecting pipeline are respectively detachably connected to the other end of the first connecting pipeline and one end of the second connecting pipeline, a spherical groove is arranged in the third connecting pipeline, and the filter structure is located in the spherical groove.

[0011] Preferably, one end of the first connecting pipe is detachably connected to the water outlet of the screw extrusion device via a first flange structure, the other end of the second connecting pipe is detachably connected to the water inlet of the flotation device via a second flange structure, one end of the third connecting pipe is detachably connected to the other end of the first connecting pipe via a third flange structure, and the other end of the third connecting pipe is detachably connected to one end of the second connecting pipe via a fourth flange structure.

[0012] Preferably, the scraper is provided with a plurality of scraper plates, the scraper drives the scraper plates to move, one end of the scraper plates is hinged to the scraper, the distance between adjacent scraper plates is such that only one scraper plate is located in the air flotation tank, and the scraper plates are made of rubber.

[0013] Preferably, it further comprises a reflux pipe, one end of which is located in the air flotation tank, and the other end of which is connected to the bubble generating device.

[0014] Compared with the prior art, the utility model has achieved the following technical effects:

[0015] The utility model combines a screw extrusion device with an air flotation device to separate the solid and liquid of the biogas slurry in the anaerobic fermentation residue, thereby improving the solid-liquid separation rate of the biogas slurry and biogas residue. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the solid-liquid separation equipment of anaerobic fermentation residue based on dissolved air flotation technology of the utility model;

[0018] Among them: 1-export; 2-slag trough; 3-slag scraper; 4-flotation tank; 5-reflux pipe; 6-bubble generating device; 7-aeration section; 8-water inlet of the flotation device; 9-second flange structure; 10-fourth flange structure; 11-filter structure; 12-third flange structure; 13-reducer; 14-motor; 15-first flange structure; 16-water outlet; 17-extrusion spiral structure; 18-feeding port; 19-slag outlet; 20-core shaft. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] The utility model aims to provide a solid-liquid separation device for anaerobic fermentation residues based on dissolved air flotation technology, thereby improving the solid-liquid separation rate of biogas slurry and biogas residue.

[0021] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0022] like Figure 1As shown: This embodiment provides a solid-liquid separation device for anaerobic fermentation residue based on dissolved air flotation technology, including a spiral extrusion device and an air flotation device, the spiral extrusion device is used to separate the solid and liquid of the anaerobic fermentation residue, the air flotation tank 4 of the air flotation device is provided with a bubble generating device 6, the bubble generating device 6 is used to generate bubbles, the bubble generating device 6 is preferably an aerator, the water outlet 16 of the spiral extrusion device is connected with the water inlet 8 of the air flotation device, so that the liquid in the anaerobic fermentation residue is mixed with the bubbles, and the bubbles are attached to the suspended particles in the liquid to drive the suspended particles to float, and a scraper 3 is provided above the air flotation tank 4, the scraper 3 is preferably a chain scraper, and the scraper 3 is used to scrape the suspended particles in the air flotation tank 4 into the slag outlet 2 of the air flotation tank 4, and the air flotation tank 4 is also provided with an outlet 1. The utility model combines a spiral extrusion device with an air flotation device to separate the solid and liquid of the biogas slurry in the anaerobic fermentation residue.

[0023] Specifically, in this embodiment, the screw extrusion device includes a motor 14, a reducer 13 and a core shaft 20. A feed port 18 is provided at the upper part of the screw extrusion device. The feed port 18 is close to one end of the screw extrusion device. The feed port 18 is funnel-shaped, which is convenient for feeding the anaerobic fermentation residue into the screw extrusion device. A water outlet 16 is provided at the lower part of the screw extrusion device. The water outlet 16 extends from one end of the screw extrusion device to the other end of the screw extrusion device. The water outlet 16 is designed to have a larger collection range, so that after the anaerobic fermentation residue enters the screw extrusion device, as long as the liquid can be separated, it can be immediately collected in the next link through the water outlet 16, so that the liquid can be discharged stably to prevent a large amount of discharge. The flow rate is easy to control. A slag outlet 19 is provided at the other end of the spiral extrusion device. The spacing of the extrusion spiral structure 17 gradually decreases from one end of the spiral extrusion device to the other end of the spiral extrusion device. The position with a larger distance can accelerate the accumulation of anaerobic fermentation residues. As the accumulation of anaerobic fermentation residues increases, the distance begins to gradually shorten, making the extrusion space smaller, which has an effect of promoting extrusion dehydration and improving the solid-liquid separation rate. The motor 14 drives the core shaft 20 to rotate through the reducer 13, and the core shaft 20 drives the extrusion spiral structure 17 outside the core shaft 20 to rotate. The anaerobic fermentation residue enters from the feed port 18. After being extruded by the extrusion spiral structure 17, the liquid flows out through the water outlet 16, and the solid is discharged through the slag outlet 19.

[0024] In this embodiment, a first connecting pipeline and a second connecting pipeline are arranged between the water outlet 16 of the spiral extrusion device and the water inlet 8 of the flotation device. The first connecting pipeline and the second connecting pipeline can be made of stainless steel. One end of the first connecting pipeline is detachably connected to the water outlet 16 of the spiral extrusion device through a first flange structure 15, and a filter structure 11 is arranged between the other end of the first connecting pipeline and one end of the second connecting pipeline. The other end of the second connecting pipeline is detachably connected to the water inlet 8 of the flotation device through a second flange structure 9.

[0025] In this embodiment, the filter structure 11 is a spherical filter made of stainless steel. A third connecting pipeline is arranged between the other end of the first connecting pipeline and one end of the second connecting pipeline. The third connecting pipeline is made of rubber. One end of the third connecting pipeline is detachably connected to the other end of the first connecting pipeline through a third flange structure 12, and the other end of the third connecting pipeline is detachably connected to one end of the second connecting pipeline through a fourth flange structure 10. A spherical groove is arranged in the third connecting pipeline, and the filter structure 11 is located in the spherical groove. The spherical filter screen made of stainless steel is overlapped with the spherical convex groove and inserted into the spherical convex groove to prevent larger solid substances from flowing into the flotation device. The liquid flowing out of the spherical filter screen will pass through two single-sided filter screens. This design takes into account that there may be a certain impact force when the liquid flows through the first layer of filter screen of the filter screen structure 11. Some impurities will rush into the filter screen structure 11 through this impact force. The first layer of filter screen can not only block certain impurities, but also reduce the flow rate of liquid substances to play a buffering role. Then, when passing through the second layer of filter screen, some obvious impurities that are not intercepted by the first layer of filter screen can be blocked. When the intercepted impurities reach a certain amount, the third flange structure 12 can be opened, and the spherical convex groove can be squeezed to replace a filter screen structure 11. The operation is simple and convenient.

[0026] In this embodiment, a plurality of scraper plates are provided on the scraper 3. The scraper plates are made of rubber. The scraper 3 drives the scraper plates to move. One end of the scraper plates is hinged to the scraper 3 so that the scraper plates can swing flexibly. The distance between adjacent scraper plates is such that only one scraper plate is located in the flotation tank 4. The scraper plate made of rubber material not only has high corrosion resistance, but also has good elasticity, so that the scraper plate can effectively avoid the instability caused by vibration caused by mechanical action during use. When the scraper plate is transmitted downward by the scraper chain of the scraper machine 3, the scraper plate can effectively alleviate the impact on the liquid surface after entering the liquid, and the scraper plate is designed to be fully covered for transportation. The function of the scraper plate is to drive the suspended matter on the liquid surface to move forward until the suspended matter is sent to the slag discharge trough 2. If there are multiple scraper plates in the liquid surface during transportation, the scraper plates will collide with the floating suspended particles in the process of entering the liquid surface, so that the microbubbles are separated from the suspended particles, thereby affecting the slag removal efficiency. The distance between adjacent scraper plates in this embodiment is such that during the operation of the scraper plate, there is only one scraper plate on the liquid surface. After the first scraper plate sends the first wave of microbubbles and suspended particles to the slag discharge trough 2, the second scraper plate successively enters the liquid surface for transportation, and the following scraper plates are similar, which can not only improve the stability of the liquid flow rate, but also reduce the impact on the slag removal effect.

[0027] In this embodiment, the bubble generating device 6 is connected to the water inlet 8 of the flotation device. When the dissolved air water passes through the aeration section 7 of the bubble generating device 6, the pressure potential energy causes the gas molecules to expand out of the dissolved air water. The gas molecules then aggregate to form microbubbles, which are then mixed with the liquid obtained by squeezing through the spiral extrusion device. After sufficient mixing, the microbubbles attach to the suspended particles in the liquid. Since their density is less than that of water, the suspended particles are driven to float up under the action of buoyancy, and then the impurities are removed by the scraper plate of the scraper 3.

[0028] In this embodiment, a reflux pipe 5 is provided in the flotation tank 4, one end of the reflux pipe 5 is located in the flotation tank, and the other end of the reflux pipe 5 is connected to the bubble generating device 6. The clear liquid treated in the flotation tank 4 is returned to the bubble generating device 6 through the reflux pipe 5, which can improve the processing efficiency of the processing system.

[0029] In this embodiment, the spiral extrusion device is a primary filter, the filter structure is a secondary filter, and the air flotation device is a tertiary filter.

[0030] When the present embodiment is working, the anaerobic fermentation residue is first injected into the spiral extrusion device, and the core shaft 20 is rotated to drive the extrusion spiral structure 17 in the device to move, and at the same time drive the anaerobic fermentation residue to flow forward, and apply a certain pressure to squeeze the liquid substance out of the filter screen and then discharge it from the water outlet 16 of the spiral extrusion device, completing the first solid-liquid separation, and the solid substance is discharged from the slag outlet 19; the liquid is filtered twice through the filter screen structure 11, and the purpose of the two filtrations is to remove more obvious solid substances. The liquid after the two filtrations enters the flotation device again, and merges with the generated microbubble water, so that the microbubbles are attached to the suspended particles in the liquid substance. Since the density of the microbubbles is less than the density of water, the suspended particles are driven to float to the liquid surface under the action of buoyancy, and the microbubbles and suspended particles are scraped off by the scraper 3, thereby realizing solid-liquid separation again.

[0031] This specification uses specific examples to illustrate the principles and implementation methods of the utility model. The above examples are only used to help understand the method and core idea of ​​the utility model. At the same time, for those skilled in the art, according to the idea of ​​the utility model, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the utility model.

Claims

1. A solid-liquid separation device for anaerobic fermentation residue based on dissolved air flotation technology, characterized in that: It comprises a screw extrusion device and an air flotation device, wherein the screw extrusion device is used for solid-liquid separation of anaerobic fermentation residues, a bubble generating device is arranged in the air flotation tank of the air flotation device, and the bubble generating device is used for generating bubbles, a water outlet of the screw extrusion device is connected with a water inlet of the air flotation device, so that the liquid in the anaerobic fermentation residues is mixed with the bubbles, and the bubbles are attached to the suspended particles in the liquid to drive the suspended particles to float, and a scraper is arranged above the air flotation tank, and the scraper is used for scraping the suspended particles in the air flotation tank into the slag outlet tank of the air flotation tank.

2. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 1, characterized in that: The spiral extrusion device comprises a motor, a reducer and a core shaft. A feed port is arranged at the upper part of the spiral extrusion device, the feed port is close to one end of the spiral extrusion device, and the feed port is funnel-shaped. The water outlet is arranged at the lower part of the spiral extrusion device, and a slag outlet is arranged at the other end of the spiral extrusion device. The motor drives the core shaft to rotate through the reducer, and the core shaft drives the extrusion spiral structure outside the core shaft to rotate. The anaerobic fermentation residue enters from the feed port, and after being extruded by the extrusion spiral structure, the liquid flows out through the water outlet, and the solid is discharged through the slag outlet.

3. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 2, characterized in that: The pitch of the extrusion spiral structure gradually decreases from one end of the spiral extrusion device to the other end of the spiral extrusion device.

4. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 1, characterized in that: A first connecting pipe and a second connecting pipe are arranged between the water outlet of the spiral extrusion device and the water inlet of the flotation device, one end of the first connecting pipe is detachably connected to the water outlet of the spiral extrusion device, a filter structure is arranged between the other end of the first connecting pipe and one end of the second connecting pipe, and the other end of the second connecting pipe is detachably connected to the water inlet of the flotation device.

5. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 4, characterized in that: The filter structure is a spherical filter. A third connecting pipeline is arranged between the other end of the first connecting pipeline and one end of the second connecting pipeline. The two ends of the third connecting pipeline are respectively detachably connected to the other end of the first connecting pipeline and one end of the second connecting pipeline. A spherical convex groove is arranged in the third connecting pipeline, and the filter structure is located in the spherical convex groove.

6. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 5, characterized in that: One end of the first connecting pipe is detachably connected to the water outlet of the screw extrusion device via a first flange structure, the other end of the second connecting pipe is detachably connected to the water inlet of the flotation device via a second flange structure, one end of the third connecting pipe is detachably connected to the other end of the first connecting pipe via a third flange structure, and the other end of the third connecting pipe is detachably connected to one end of the second connecting pipe via a fourth flange structure.

7. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 1, characterized in that: The scraper is provided with a plurality of scraper plates, which are driven by the scraper to move. One end of the scraper plate is hinged to the scraper, and the distance between adjacent scraper plates is such that only one scraper plate is located in the air flotation tank. The scraper plates are made of rubber.

8. The solid-liquid separation equipment for anaerobic fermentation residues based on dissolved air flotation technology according to claim 1, characterized in that: It also includes a reflux pipe, one end of which is located in the air flotation tank, and the other end of which is connected to the bubble generating device.

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