Red mud membrane biogas digester for degrading COD (Chemical Oxygen Demand) ammonia nitrogen by anaerobic fermentation of manure water and sewage

Abstract

The utility model belongs to the technical field of manure sewage recycling, and particularly relates to a manure sewage anaerobic fermentation COD (Chemical Oxygen Demand) ammonia nitrogen degradation red mud membrane biogas digester which comprises a digester body and a combined membrane, the inner walls and the bottom surfaces of the enclosure frame and the pool bottom frame are sealed and welded through the enclosure plates to form an integral structure, baffle plates are arranged in the enclosure frame and the pool bottom frame, and the combined membrane and the methane production area are correspondingly provided with pneumatic flow mixing mechanisms; and a heating mechanism is arranged in the methane production area in the pool bottom frame. According to the utility model, the combined membrane is matched with the pneumatic mixed flow mechanism in the pool bottom frame, and methane gas generated by the methane production area is utilized to inflate the gas distribution coil pipe in the hydrolytic acidification area, so that manure-water mixed liquid in the hydrolytic acidification area generates an upward agitating and mixing effect. According to the design, the hydrolytic acidification efficiency is remarkably improved, the phenomena of scum crusting and precipitation layering can be effectively reduced, and the mass transfer efficiency is greatly improved.

Description

Technical Field

[0001] This utility model belongs to the field of sewage recycling technology, specifically relating to a red mud membrane biogas digester for anaerobic fermentation and degradation of COD and ammonia nitrogen in sewage. Background Technology

[0002] Currently, although traditional red mud membrane biogas digesters have a certain capacity to degrade COD (chemical oxygen demand) and ammonia nitrogen during the anaerobic fermentation treatment of sewage, they still face many technical bottlenecks in long-term operation, which seriously restrict their treatment efficiency and stability.

[0003] In anaerobic fermentation, mixing is often achieved through mechanical or natural stirring. However, this can easily lead to problems such as scum crusting and sediment stratification, resulting in reduced effective reaction volume and low mass transfer efficiency. While mechanical stirring is more effective, it increases equipment investment costs and reduces users' willingness to use biogas digesters. Especially in winter or cold regions, the temperature inside the digester can drop significantly due to ambient temperature fluctuations, weakening the activity of anaerobic microorganisms, causing a sharp decline in methane production, and severely impacting wastewater treatment efficiency.

[0004] Therefore, this utility model proposes a red mud membrane biogas digester for anaerobic fermentation of sewage to degrade COD and ammonia nitrogen, in order to solve the above-mentioned technical problems. Utility Model Content

[0005] The purpose of this invention is to provide a red mud membrane biogas digester for anaerobic fermentation of sewage to degrade COD and ammonia nitrogen, which can solve the above-mentioned technical problems.

[0006] The specific technical solution adopted by this utility model is as follows:

[0007] This utility model provides an anaerobic fermentation biogas digester for degrading COD and ammonia nitrogen in sewage and red mud, comprising a digester body and a combined membrane. The digester body includes an enclosure frame, a bottom frame, and enclosure plates. The bottom frame is located on the bottom surface of the enclosure frame, and the bottom surface of the bottom frame is inclined at an angle of 30°. The enclosure frame and the inner wall and bottom surface of the bottom frame are sealed and welded together by the enclosure plates to form an integral structure. Baffles are provided inside the enclosure frame and the bottom frame, which divide the digester body into a hydrolysis acidification zone and a methanogenic zone. Two combined membranes are provided, one covering the hydrolysis acidification zone and the other covering the methanogenic zone. The combined membranes and the methanogenic zone are respectively provided with a pneumatic mixing mechanism. The methanogenic zone inside the bottom frame is provided with a heating mechanism.

[0008] The pneumatic mixing mechanism includes an air distribution coil, a return air pipe, and a return valve. The air distribution coil is fixedly installed on the bottom baffle plate corresponding to the hydrolysis acidification zone of the pool bottom frame. The return air pipe is sealed through the baffle plate and communicates with the air distribution coil. Several micro-holes are evenly opened on the surface of the air distribution coil.

[0009] A pressure sensor is installed on the top of the combined membrane. The two combined membranes are connected by a gas collection pipe. An exhaust valve for regulating the gas pressure inside the membrane is installed on the gas collection pipe. The return gas pipe is connected to the gas collection pipe corresponding to the methanogenic zone through a three-way connector and is located downstream of the exhaust valve. The return valve is integrated into the return gas pipe.

[0010] Preferably, the heating mechanism includes a heating coil, a return pipe, an input pipe, and a heating device. The heating coil is coiled around the bottom baffle plate corresponding to the methanogenic zone of the pool bottom frame. The return pipe and the input pipe pass through the baffle plates on both sides and are connected to both ends of the heating coil. The upper end of the return pipe is connected to the heating device, and the heating device is fixedly installed on the ground.

[0011] Preferably, a circulation pump is installed on the outer wall of the heating device, the inlet of the circulation pump is connected to the heating device through an inlet pipe, the upper end of the input pipe is connected to the outlet of the circulation pump, and a controller is integrated on the surface of the heating device.

[0012] Preferably, the baffle plate has a hollow structure and is vertically fixed to the middle of the enclosure frame and the bottom frame of the pool. The baffle plate has an inlet hole on the side wall facing the hydrolysis acidification zone and an outlet hole on the side wall facing the methanogenic zone. The outlet hole is higher than the inlet hole. The baffle plate is equipped with a guide baffle that is flush with the inlet hole.

[0013] Preferably, a backflush pipe is installed on the side wall of the pool bottom frame. The two ends of the backflush pipe pass through the baffles of the hydrolysis acidification zone and the methanogenic zone, respectively. The backflush pipe is equipped with a double-sealed valve, and the valve control lever extends to the ground operating platform.

[0014] Preferably, the enclosure plate is provided with a raw liquid feed pipe that communicates with the hydrolysis acidification zone, the enclosure plate corresponding to the methanogenic zone of the pool bottom frame is provided with a drain pipe, and the bottom of the enclosure plate corresponding to the hydrolysis acidification zone is provided with a slag discharge pipe. The slag discharge pipe and the backflushing pipe form a flushing circuit.

[0015] Preferably, the composite membrane has a three-layer structure, namely an outer membrane, a sandwich filler, and an inner membrane, wherein the sandwich filler is disposed between the outer membrane and the inner membrane.

[0016] Preferably, a hydrogen sulfide concentration sensor is added to the top of the combined membrane, and the installation position is between the gas collecting pipe and the pressure sensor.

[0017] The beneficial effects are:

[0018] 1. This utility model utilizes a combination membrane and a pneumatic mixing mechanism within the pool bottom frame. Methane gas generated in the methanogenic zone aerates the gas distribution coils in the hydrolysis and acidification zone, creating an upward turbulent mixing effect in the fecal-water mixture. This design not only significantly improves hydrolysis and acidification efficiency but also effectively reduces scum crusting and sediment stratification, greatly enhancing mass transfer efficiency.

[0019] 2. This utility model, through its heating mechanism, can effectively cope with changes in ambient temperature during winter and precisely control the temperature of the fermentation liquid in the methanogenic zone, thereby significantly improving fermentation efficiency in winter.

[0020] 3. The multi-layer structure design of the combined membrane adopted in this utility model has excellent anti-ultraviolet, anti-aging and heat preservation properties, which can significantly extend the service life of the device. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0022] Figure 2 This is a schematic diagram of the structure from another side view of this utility model;

[0023] Figure 3 This is a schematic diagram of the cross-sectional structure of the semi-buried lowering method of this utility model;

[0024] Figure 4 This is a schematic diagram of the combined membrane structure of this utility model.

[0025] The attached diagram lists the components represented by each number as follows:

[0026] 1. Enclosure frame; 2. Pool bottom frame; 3. Enclosure panel; 4. Composite membrane; 41. Outer membrane; 42. Interlayer filling; 43. Inner membrane; 5. Pressure sensor; 6. Gas collection pipe; 7. Exhaust valve; 8. Backflushing pipe; 9. Valve; 10. Extension rod; 11. Return gas pipe; 12. Slag discharge pipe; 13. Gas distribution coil; 14. Heating coil; 15. Return pipe; 16. Input pipe; 17. Circulation pump; 18. Heating equipment; 19. Controller; 20. Raw material feed pipe; 21. Baffle plate; 21a. Liquid inlet; 21b. Liquid outlet; 22. Guide baffle; 23. Return valve; 24. Drain pipe. Detailed Implementation

[0027] To make the objectives and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of this utility model and does not strictly limit the scope of protection specifically claimed by this utility model.

[0028] like Figure 1-4As shown, a red mud membrane biogas digester for anaerobic fermentation and degradation of COD and ammonia nitrogen in sewage includes a digester body and a combined membrane 4. The digester body includes a retaining frame 1, a bottom frame 2, and a retaining plate 3. The bottom frame 2 is located on the bottom surface of the retaining frame 1, and the bottom surface of the bottom frame 2 is inclined at an angle of 30°. The inner walls and bottom surfaces of the retaining frame 1 and the bottom frame 2 are sealed and welded together by the retaining plate 3 to form an integral structure. The retaining frame 1 and the bottom frame 2 are equipped with baffles 21, which divide the digester body into a hydrolysis acidification zone and a methanogenic zone. Two combined membranes 4 are provided, which cover the hydrolysis acidification zone and the methanogenic zone respectively. The combined membranes 4 and the methanogenic zone are equipped with pneumatic mixing mechanisms. The methanogenic zone in the bottom frame 2 is equipped with a heating mechanism.

[0029] The pneumatic mixing mechanism includes an air distribution coil 13, a return air pipe 11, and a return valve 23. The air distribution coil 13 is fixedly installed on the bottom baffle 3 corresponding to the hydrolysis acidification zone of the pool bottom frame 2. The return air pipe 11 is sealed through the baffle 3 and connected to the air distribution coil 13. Several micro-holes are evenly opened on the surface of the air distribution coil 13.

[0030] A pressure sensor 5 is installed on the top of the combined membrane 4. The two combined membranes 4 are connected by a gas collecting pipe 6. An exhaust valve 7 for regulating the gas pressure inside the membrane is installed on the gas collecting pipe 6. The return gas pipe 11 is connected to the gas collecting pipe 6 corresponding to the methanogenic zone through a three-way connector and is located downstream of the exhaust valve 7. The return valve 23 is integrated on the return gas pipe 11. Both the return valve 23 and the exhaust valve 7 are electromagnetically controlled valves 9.

[0031] As an optional implementation, the heating mechanism includes a heating coil 14, a return pipe 15, an input pipe 16, and a heating device 18. The heating coil 14 is coiled around the bottom baffle 3 corresponding to the methanogenic zone of the pool bottom frame 2. The return pipe 15 and the input pipe 16 pass through the baffle 3 on both sides and are connected to both ends of the heating coil 14. The upper end of the return pipe 15 is connected to the heating device 18. The heating device 18 is fixedly installed on the ground and uses an electric heating water circulation device to maintain a constant temperature for the fermentation liquid in the methanogenic zone during winter.

[0032] See attached document Figure 2 A circulation pump 17 is installed on the outer wall of the heating device 18. The inlet of the circulation pump 17 is connected to the heating device 18 through the inlet pipe. The upper end of the input pipe 16 is connected to the outlet of the circulation pump 17. A controller 19 is integrated on the surface of the heating device 18. The controller 19 is bidirectionally connected to the pressure sensor 5, the exhaust valve 7, the return valve 23 and the heating device 18 through the signal line.

[0033] See attached document Figure 3The baffle plate 21 is a hollow structure and is vertically fixed in the middle of the enclosure frame 1 and the bottom frame 2. The baffle plate 21 has an inlet hole 21a on the side wall facing the hydrolysis acidification zone and an outlet hole 21b on the side wall facing the methanogenic zone. The outlet hole 21b is higher than the inlet hole 21a. The baffle plate 21 is equipped with a guide baffle 22 that is flush with the inlet hole 21a to realize the directional flow of the acidified liquid.

[0034] Furthermore, a backflushing pipe 8 is installed on the side wall of the pool bottom frame 2. The two ends of the backflushing pipe 8 pass through the baffle plate 3 of the hydrolysis acidification zone and the methanogenic zone, respectively. A double-sealed valve 9 is provided on the backflushing pipe 8. The valve 9 control lever extends to the ground operating platform to facilitate the operation of the valve 9 by the operator on the ground.

[0035] Furthermore, the enclosure plate 3 is equipped with a raw liquid feed pipe 20 that is connected to the hydrolysis acidification zone. The enclosure plate 3 corresponding to the methanogenic zone of the pool bottom frame 2 is equipped with a drain pipe 24. The bottom of the enclosure plate 3 corresponding to the hydrolysis acidification zone is equipped with a slag discharge pipe 12. The slag discharge pipe 12 and the backflushing pipe 8 form a flushing circuit to improve the cleaning effect of the sediment in the hydrolysis acidification zone.

[0036] See attached document Figure 4 The composite membrane 4 has a three-layer structure, namely an outer membrane 41, a sandwich filler 42, and an inner membrane 43. The sandwich filler 42 is located between the outer membrane 41 and the inner membrane 43. The outer membrane 41 is a red mud-polyethylene composite membrane with strong UV resistance and weather resistance (thickness ≥ 1.5 mm), and the surface is coated with a light-reflecting coating to reduce UV aging. The inner membrane 43 uses an antibacterial and anti-corrosion HDPE membrane to prevent hydrogen sulfide corrosion and extend its service life. The sandwich filler 42 is an aerogel insulation material (thickness 3.5 cm), which can improve the insulation performance in winter.

[0037] Furthermore, a hydrogen sulfide concentration sensor is added to the top of the combined membrane 4, with the installation position between the gas collecting pipe 6 and the pressure sensor 5, to improve the leak detection effect after the gas collecting pipe 6 and the pressure sensor 5 expand.

[0038] Using the above structure, the following steps are included:

[0039] 1. Normal operation phase:

[0040] (1) When the pressure sensor 5 detects that the gas pressure in the methanogenic zone reaches 5 kPa, the controller 19 automatically opens the return valve 23, allowing some biogas to enter the gas distribution coil 13 through the return pipe 11.

[0041] (2) Biogas is released from the micropores of the gas distribution coil 13, which produces a bubbling and stirring effect on the liquid in the hydrolysis acidification zone for 10-15 minutes / time, 3-4 times a day.

[0042] (3) The acidified liquid enters the hollow cavity through the inlet hole 21a of the baffle 21, and flows into the methanogenic zone from the high outlet hole 21b after being guided by the guide baffle 22.

[0043] 2. Maintenance and operation phase:

[0044] (1) Operate the backflush pipe 8 valve 9 weekly through the extension rod 10 to backflush the bottom of the hydrolysis acidification zone with the liquid from the methanogenic zone;

[0045] (2) After rinsing, open valve 9 of slag discharge pipe 12 to discharge the sediment;

[0046] (3) Regularly sample and test the degradation effect of COD and ammonia nitrogen through the drain pipe 24.

[0047] The above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. All standard parts used in this application can be purchased from the market, and can be customized according to the description and drawings. The specific connection methods of each part all adopt conventional methods such as bolts, rivets, and welding, which are mature technologies in the prior art. The machinery, parts, and equipment all adopt conventional models in the prior art. The control method is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art, and is common knowledge in the field. Furthermore, this application is mainly used to protect mechanical devices, so the control method and circuit connection will not be explained in detail here. Structures, devices, and operating methods not specifically described or explained in this utility model, unless otherwise specified or limited, are implemented according to conventional methods in the field.

Claims

1. A fecal water sewage anaerobic fermentation degradation COD ammonia nitrogen red mud membrane biogas tank, characterized by: The system includes a pool body and a combined membrane (4). The pool body includes a enclosure frame (1), a bottom frame (2), and a baffle plate (3). The bottom frame (2) is located on the bottom surface of the enclosure frame (1), and the bottom surface of the bottom frame (2) is tilted at an angle of 30°. The inner wall and bottom surface of the enclosure frame (1) and the bottom frame (2) are sealed and welded together by the baffle plate (3) to form an integral structure. The enclosure frame (1) and the bottom frame (2) are equipped with baffle plates (21). The baffle plates (21) divide the pool body into a hydrolysis acidification zone and a methanogenic zone. The combined membrane (4) consists of two membranes, which cover the hydrolysis acidification zone and the methanogenic zone, respectively. The combined membrane (4) and the methanogenic zone are equipped with pneumatic mixing mechanisms. The methanogenic zone inside the bottom frame (2) is equipped with a heating mechanism. The pneumatic mixing mechanism includes an air distribution coil (13), a return air pipe (11), and a return valve (23). The air distribution coil (13) is fixedly installed on the bottom baffle (3) corresponding to the hydrolysis acidification zone of the pool bottom frame (2). The return air pipe (11) is sealed through the baffle (3) and communicates with the air distribution coil (13). The surface of the air distribution coil (13) is uniformly opened with several micro-holes. A pressure sensor (5) is installed on the top of the combined membrane (4). The two combined membranes (4) are connected by a gas collection pipe (6). An exhaust valve (7) for regulating the gas pressure inside the membrane is installed on the gas collection pipe (6). The return gas pipe (11) is connected to the gas collection pipe (6) corresponding to the methanogenic zone through a three-way connector and is located downstream of the exhaust valve (7). The return valve (23) is integrated on the return gas pipe (11).

2. The red mud film biogas digester for degrading COD and ammonia nitrogen in fecal sewage according to claim 1, characterized in that: The heating mechanism includes a heating coil (14), a return pipe (15), an input pipe (16), and a heating device (18). The heating coil (14) is coiled around the bottom baffle (3) corresponding to the methanogenic zone of the pool bottom frame (2). The return pipe (15) and the input pipe (16) pass through the baffles (3) on both sides and are connected to both ends of the heating coil (14). The upper end of the return pipe (15) is connected to the heating device (18), which is fixedly installed on the ground.

3. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 2, characterized in that: The heating device (18) is equipped with a circulation pump (17) on its outer wall. The inlet of the circulation pump (17) is connected to the heating device (18) through an inlet pipe. The upper end of the input pipe (16) is connected to the outlet of the circulation pump (17). The surface of the heating device (18) is integrated with a controller (19).

4. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 3, characterized in that: The baffle plate (21) is a hollow structure and is vertically fixed in the middle of the enclosure frame (1) and the bottom frame (2). The baffle plate (21) has an inlet hole (21a) on the side wall facing the hydrolysis acidification zone and an outlet hole (21b) on the side wall facing the methanogenic zone. The outlet hole (21b) is higher than the inlet hole (21a). The baffle plate (21) is provided with a guide baffle (22) that is flush with the inlet hole (21a).

5. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 4, characterized in that: The bottom frame (2) of the pool is equipped with a backflush pipe (8) on its side wall. The two ends of the backflush pipe (8) pass through the baffle plate (3) of the hydrolysis acidification zone and the methanogenic zone, respectively. The backflush pipe (8) is equipped with a double-sealed valve (9), and the valve (9) control lever extends to the ground operation platform.

6. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 5, characterized in that: The enclosure plate (3) is provided with a raw liquid feed pipe (20) that is connected to the hydrolysis acidification zone. The enclosure plate (3) corresponding to the methane production zone of the pool bottom frame (2) is equipped with a drain pipe (24). The bottom of the enclosure plate (3) corresponding to the hydrolysis acidification zone is provided with a slag discharge pipe (12). The slag discharge pipe (12) and the backflushing pipe (8) form a flushing circuit.

7. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 6, characterized in that: The combined membrane (4) has a three-layer structure, namely an outer membrane (41), a sandwich filler (42) and an inner membrane (43), wherein the sandwich filler (42) is disposed between the outer membrane (41) and the inner membrane (43).

8. The red mud film biogas digester for degrading COD and ammonia-nitrogen in fecal sewage according to claim 7, characterized in that: A hydrogen sulfide concentration sensor is added to the top of the combined membrane (4), and the installation position is between the gas collecting pipe (6) and the pressure sensor (5).

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