Semi-dry anaerobic digestion reactor
By using a biogas stirring, mechanical stirring, and a combination of gastrointestinal stirring in the middle of the central digestive liquid, the mixing effect of dry anaerobic digestive reactor in low solid -content garbage treatment is not good. The efficient and stable operation of the semi -dry anaerobic reactor.
Patent Information
- Application Number
- CN202420563184.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-22
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-03-22
AI Technical Summary
The existing dry anaerobic digestion reactors are prone to delamination when disposing of low solid-containing waste, and the mixing effect is not ideal, and the bottom sediment is prone to accumulate, resulting in difficulty in operating the agitator or shutdown failure.
The semi -dry anaerobic digestive reactor is used to mix through the combination of biogas, mechanical stirring, and the refund of the central digestive fluid to ensure that the anaerobic reactor mixes evenly at a certain solid content concentration.
The uniform mixing and effective residue discharge of anaerobic reactors in a higher solid rate can avoid the problem of difficulty accumulation and the operation of the mixer, and ensure the efficient and stable operation of the reactor.
Smart Images
Figure CN222411545U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of urban organic solid waste treatment, in particular to a semi-dry anaerobic digestion reactor. Background Art
[0002] Since the country started to classify domestic waste in 2017, major and medium-sized cities in China have stepped up the construction of terminal treatment facilities for the resource utilization of classified kitchen waste. At present, most of the domestic processes for kitchen waste are imported from foreign complete sets of "dry anaerobic digestion" processes. Conventional dry anaerobic digestion processes require that the solid content of raw materials cannot be less than 25%. Due to the implementation of waste classification, many cities and regions, especially in the southern region, have a solid content of only 20% of classified kitchen waste, which makes the dry anaerobic digestion system prone to stratification during actual operation, and the mixing effect is not ideal. Since the bottom area of most dry anaerobic digestion reactors is small, it is easy to accumulate sediment at the bottom, causing problems such as difficulty in the operation of the agitator or the risk of overload shutdown.
[0003] CN 212800322 proposes a high-concentration anaerobic fermentation device, which mixes the materials in the tank by arranging a number of direct-entry stirring units on a rectangular anaerobic reactor. The anaerobic reactor is 35-40m long and 6-10m wide, and the inlet and outlet are arranged on both sides of the length direction. CN 214115509 proposes a high-concentration anaerobic fermentation device with differential stirring. In order to avoid the dead corner of the stirring area of the single-axis stirrer arranged in the length direction at the bottom of the anaerobic reactor, the structure of the anaerobic fermentation device is a semi-cylindrical structure at the bottom and a rectangular structure at the top, and the inlet and outlet are also located on both sides of the length direction. This type of dry anaerobic reactor has a small bottom area, and the sediment is very easy to precipitate and accumulate in the length direction, which can easily cause the operation of the stirrer to be difficult or overload shutdown failure. Utility Model Content
[0004] The main technical problem solved by the utility model is to provide a semi-dry anaerobic digestion reactor, which ensures uniform mixing of the anaerobic reactor at a certain solid content concentration through a combined stirring form of biogas stirring, mechanical stirring and reflux of the middle digestion liquid, thereby realizing efficient and stable operation of the semi-dry anaerobic reactor.
[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide a semi-dry anaerobic digestion reactor, including an anaerobic reactor body, a feed port, a discharge port, a sediment stirring mechanism, and a biogas stirring mechanism. The anaerobic reactor body is hollow and has a feed port and a discharge port distributed up and down. The anaerobic reactor body is connected to a sediment stirring mechanism extending to the bottom from the top center, and the anaerobic reactor body is connected to a biogas stirring mechanism extending to the bottom from the top around the circumference.
[0006] In a preferred embodiment of the utility model, the biogas stirring mechanism includes a biogas stirring branch pipe, a biogas distributor, a biogas stirring main pipe, a biogas stirring air inlet, and a biogas outlet. The anaerobic reactor body is vertically provided with a plurality of biogas stirring branch pipes at equal intervals along the inner wall. The biogas stirring branch pipe is connected to a biogas distributor at the bottom of the anaerobic reactor body. The biogas distributor is arranged at the bottom of the anaerobic reactor body. The top of the biogas stirring branch pipe is connected in parallel to an external biogas stirring main pipe. The biogas stirring main pipe is provided with a biogas stirring air inlet, and the top surface of the anaerobic reactor body is provided with a biogas outlet.
[0007] In a preferred embodiment of the utility model, the sediment stirring mechanism includes a reduction motor, a stirring shaft, a sealing water seal, and paddles. The reduction motor is installed on the top surface of the anaerobic reactor body. The center of the top surface of the anaerobic reactor body is opened. The reduction motor is connected to the stirring shaft from the opening. The bottom of the anaerobic reactor body is provided with a shaft seat and carries the stirring shaft. A sealing water seal is provided between the opening and the stirring shaft. The stirring shaft is provided with paddles at high positions such as the discharge port.
[0008] In a preferred embodiment of the utility model, a biogas slurry return port is opened in the middle of the anaerobic reactor body, and the biogas slurry return port is connected to the feed port.
[0009] In a preferred embodiment of the utility model, a coil heat exchange pipeline is connected to the inside of the anaerobic reactor body, and the coil heat exchange pipeline is spirally arranged in the middle and lower part of the anaerobic reactor body.
[0010] The beneficial effect of the utility model is that the semi-dry anaerobic digestion reactor provided by the utility model ensures uniform mixing of the anaerobic reactor at a certain solid content concentration through a combined stirring form of biogas stirring, mechanical stirring and reflux of the middle digestion liquid, thereby realizing efficient and stable operation of the semi-dry anaerobic reactor. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:
[0012] Figure 1 It is a front view of a semi-dry anaerobic digestion reactor of the utility model;
[0013] Figure 2 The utility model is a top view of a semi-dry anaerobic digestion reactor. DETAILED DESCRIPTION
[0014] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0015] like Figure 1-2 As shown, the embodiment of the utility model includes:
[0016] A semi-dry anaerobic digestion reactor comprises an anaerobic reactor body 1, a feed port 2, a discharge port 7, a sediment stirring mechanism 8, and a biogas stirring mechanism 3. The anaerobic reactor body 1 is hollow and has a feed port 2 and a discharge port 7 distributed up and down. The anaerobic reactor body 1 is connected from the top center to a sediment stirring mechanism 8 extending to the bottom. The anaerobic reactor body 1 is connected from the top around the circumference to the biogas stirring mechanism 3 extending to the bottom.
[0017] Among them, the biogas stirring mechanism 3 includes a biogas stirring branch pipe, a biogas distributor 5, a biogas stirring main pipe, a biogas stirring air inlet 4, and a biogas outlet 6. The anaerobic reactor body 1 is vertically provided with a plurality of biogas stirring branch pipes at equal intervals along the inner wall. The biogas stirring branch pipe is connected to the biogas distributor 5, and the biogas distributor 5 is arranged at the bottom of the anaerobic reactor body 1. The top of the biogas stirring branch pipe is connected in parallel to a biogas stirring main pipe, and the biogas stirring main pipe is provided with a biogas stirring air inlet 4. The top surface of the anaerobic reactor body 1 is provided with a biogas outlet 6.
[0018] Furthermore, the sediment stirring mechanism 8 includes a reduction motor, a stirring shaft, a sealing water seal 12, and a paddle 9. The reduction motor is installed on the top surface of the anaerobic reactor body 1. The center of the top surface of the anaerobic reactor body 1 is opened. The reduction motor is connected to the stirring shaft from the bottom of the opening. The bottom of the anaerobic reactor body 1 is provided with a shaft seat and carries the stirring shaft. A sealing water seal 12 is provided between the opening and the stirring shaft. The stirring shaft is provided with a paddle 9 at a high position such as the discharge port 7.
[0019] Furthermore, a biogas slurry return port 10 is opened in the middle of the anaerobic reactor body 1 , and the biogas slurry return port 10 is connected to the feed port 2 .
[0020] Furthermore, a coil heat exchange pipeline 11 is connected to the inside of the anaerobic reactor body 1 , and the coil heat exchange pipeline 11 is spirally arranged in the middle and lower part of the anaerobic reactor body 1 .
[0021] The main mechanisms of the device include an anaerobic reactor body 1, a biogas stirring mechanism 3, and a sediment stirring mechanism 8. The solid content of the material in the tank of the anaerobic reactor is in the range of 5%-15%, preferably 10%.
[0022] The anaerobic reactor body 1 is a cylindrical structure with a height-to-diameter ratio of 0.5-1.0, preferably 0.7. The anaerobic reactor body 1 is provided with a feed inlet 2, a discharge port 7, a biogas outlet 6, a biogas reflux port 10, a coil heat exchange pipeline 11 and attached instrument interfaces such as liquid level, pressure and temperature, and the outer wall of the reactor is provided with insulation measures.
[0023] The feed port 2 is arranged at the upper part of one side of the anaerobic reactor body and is higher than the working liquid level. The discharge port 7 is arranged at the lower part of the other side of the anaerobic reactor body and is flush with the sediment scraper plate. The feed and discharge of the anaerobic reactor are determined based on the liquid level displayed by the liquid level gauge equipped with the anaerobic reactor.
[0024] The biogas stirring mechanism 3 is provided with a biogas stirring air inlet 4 and a biogas distributor 5, and the biogas stirring air inlet 4 and the biogas distributor 5 are connected in parallel by a biogas stirring main pipe. When the biogas stirring mechanism 3 works normally, the biogas pressure in the pipeline is related to the actual working liquid level in the anaerobic reactor, and the biogas pressure is between 0.0 and 3.0 bar. The biogas stirring mechanism 3 is connected to the biogas stirring main pipe through a biogas pipeline by 2-12 biogas distributors, and an automatic valve is set between the biogas pipeline and the biogas main pipe.
[0025] The biogas distributor 5 is a conical structure, the upper part is connected to the biogas stirring main pipe through the biogas pipeline, and the lower part is evenly arranged with 6-12 round holes with a diameter of 20-50mm to disperse the gas, which plays a role in increasing the stirring area. The biogas distributor 5 is arranged in the anaerobic reactor and is 300-500mm higher than the stirring blade of the sediment stirring mechanism. When the biogas distributor 5 is stirring the biogas, aeration stirring is performed according to a certain order. 1-12 biogas distributors can be started for aeration stirring each time, preferably 2-4 as a group, alternately, and the aeration time of each group is 10-20min.
[0026] The diameter of the biogas outlet 6 is usually 1.0-3.0 times, preferably 2.0 times, that of the biogas stirring inlet 4 .
[0027] The sediment stirring mechanism 8 includes a motor, a reducer, a sealing water seal 12, a stirring shaft and a paddle. The motor of the sediment stirring mechanism 8 is an explosion-proof motor, and the reducer is a large gear ratio reducer. The sediment stirring mechanism 8 usually runs at a low speed of 0.3-1.0rpm and runs continuously for 24 hours. The stirring rotation direction is consistent with the aeration switching direction of the biogas stirring mechanism. The stirring shaft connection port between the sediment stirring mechanism 8 and the anaerobic reactor body 1 is sealed in the form of a water seal. The device has a simple and reliable structure and can also play a role in positive and negative pressure protection of the anaerobic reactor in an emergency.
[0028] The sediment scraper plate 9 is made of special wear-resistant steel welded on the sediment agitator blades. The sediment agitator blades are inclined at an angle of 15-30 degrees so that when the sediment stirring mechanism is running, the sediment can be gradually pushed around and finally discharged out of the anaerobic reactor through the discharge port 7.
[0029] The biogas slurry return port 10 is arranged in the middle of the side of the anaerobic reactor body 1 so that the properties of the returned biogas slurry are more uniform.
[0030] The coil heat exchanger 11 is arranged on the inner wall of the anaerobic reactor in a spiral ascending form, and uses hot water as a heat source to heat and keep the anaerobic reactor warm. A hot water circulation pump is provided externally, and the pump is automatically started and stopped according to the temperature displayed by the temperature sensor provided with the anaerobic reactor.
[0031] The stirrer sealing water seal 12 is composed of two large and one small, hollow cylindrical containers with one end open, which are stacked in reverse up and down. The smaller one is fixed on the stirring shaft, and the larger one is fixed on the anaerobic reactor. The larger hollow cylinder is used to hold water, and the water level is 30-60mm, preferably 50mm.
[0032] like Figure 1 and Figure 2 As shown, it shows a semi-dry anaerobic reactor implemented in the utility model, and the semi-dry anaerobic reactor is used for processing and disposing of kitchen waste.
[0033] In this embodiment, the processed material is extruded slurry after pretreatment of kitchen waste, the process is intermittent material loading and unloading, the processing capacity of the device is 3.0m3 / h, the effective volume of the device is 100m³, the slurry residence time is 33d, the reaction temperature is 35~38℃, the operating pressure of the biogas stirring mechanism 3 is 0.21bar, and the speed of the sediment stirring mechanism 8 is 0.3rpm.
[0034] In this embodiment, the anaerobic reactor has completed the work of inoculation, acclimatization and debugging before feeding, the solid content in the anaerobic reactor is 12.5%, and the internal environment temperature of the anaerobic reactor is 37°C.
[0035] The feed port 2 is used to receive the slurry generated by the front-end pretreatment. The solid content of the slurry is 20%. When the liquid level in the anaerobic reactor is lower than the design range of the working liquid level, intermittent feeding can be performed into the anaerobic reactor. During the feeding process, the biogas slurry at the biogas slurry return port 10 will flow back to the front end, and after being mixed with the slurry in a certain proportion, it will be pumped into the anaerobic reactor by the delivery pump.
[0036] The biogas mixing mechanism 3 has 6 groups of biogas distributors, 2 adjacent ones form a group, and three groups are operated alternately at a time.
[0037] The sediment stirring mechanism 8 operates continuously for 24 hours at a rotation speed of 0.3 rpm.
[0038] The discharge port 7 is used to discharge the digested residue and inert substances in the anaerobic reactor. When the liquid level in the anaerobic reactor is higher than the designed working liquid level range, the discharge can be intermittent. During the discharge process, the automatic valve on the discharge port 7 should be combined with the back-end dehydration process and the anaerobic supporting liquid level working range as the system start and stop conditions.
[0039] The utility model is characterized in that:
[0040] 1) The semi-dry anaerobic reactor of the utility model adopts a smaller height-to-diameter ratio, which is beneficial to the sediment at the bottom of the tank and avoids the influence of sediment accumulation on the stirring mechanism. The material inlet and outlet adopt the upper inlet and lower outlet method, which is beneficial to the discharge of sediment. The reactor operates at a solid content of 5%-15%, solving the problem that auxiliary materials must be added during the current dry anaerobic operation.
[0041] 2) The semi-dry anaerobic reactor of the utility model utilizes a combination of biogas stirring and mechanical stirring, and adopts upper insertion biogas stirring, which can effectively prevent the blockage of the biogas distributor. The low-speed operation of the sediment stirring mechanism avoids the accumulation of sediment materials at the bottom of the tank, and realizes uniform mixing and effective slag discharge of the anaerobic reactor at a higher solid content;
[0042] 3) The semi-dry anaerobic reactor of the utility model has flexible control mode, and the aeration distribution air pipe of the biogas stirring mechanism can be flexibly combined and configured under different process control conditions to achieve different stirring and mixing functions;
[0043] 4) The semi-dry anaerobic reactor of the utility model has low energy consumption and convenient inspection and maintenance. The overall structure of the anaerobic reactor is simple. The sediment stirring mechanism is a high-torque, low-speed device with little wear. The biogas stirring mechanism is mainly a combination of related pipeline processes, and daily inspection and maintenance of the biogas air compressor is sufficient.
[0044] In summary, the utility model provides a semi-dry anaerobic digestion reactor, which ensures uniform mixing of the anaerobic reactor at a certain solid content concentration through a combined stirring form of biogas stirring, mechanical stirring and reflux of the middle digestate, thereby achieving efficient and stable operation of the semi-dry anaerobic reactor.
[0045] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A semi-dry anaerobic digestion reactor, characterized in that: The anaerobic reactor comprises an anaerobic reactor body, a feed port, a discharge port, a sediment stirring mechanism, and a biogas stirring mechanism. The anaerobic reactor body is hollow and has a feed port and a discharge port distributed up and down. The anaerobic reactor body is connected from the top center to a sediment stirring mechanism extending to the bottom. The anaerobic reactor body is connected from the top around the circumference to a biogas stirring mechanism extending to the bottom. The biogas stirring mechanism comprises a biogas stirring branch pipe, a biogas distributor, a biogas stirring main pipe, a biogas stirring air inlet and a biogas outlet. The anaerobic reactor body is vertically provided with a plurality of biogas stirring branch pipes at equal intervals along the inner wall. The biogas stirring branch pipe is connected to a biogas distributor at the bottom of the anaerobic reactor body. The top of the biogas stirring branch pipe is connected in parallel to a biogas stirring main pipe. The biogas stirring main pipe is provided with a biogas stirring air inlet. The top surface of the anaerobic reactor body is provided with a biogas outlet.
2. The semi-dry anaerobic digestion reactor according to claim 1, characterized in that: The sediment stirring mechanism comprises a reduction motor, a stirring shaft, a sealing water seal, and paddles. The reduction motor is installed on the top surface of the anaerobic reactor body. The center of the top surface of the anaerobic reactor body is opened. The reduction motor is connected to the stirring shaft from the opening. The bottom of the anaerobic reactor body is provided with a shaft seat to carry the stirring shaft. A sealing water seal is provided between the opening and the stirring shaft. The stirring shaft is provided with paddles at high positions such as the discharge port.
3. The semi-dry anaerobic digestion reactor according to claim 1, characterized in that: A biogas slurry return port is provided in the middle of the anaerobic reactor body, and the biogas slurry return port is connected to the feed port.
4. The semi-dry anaerobic digestion reactor according to claim 1, characterized in that: A coil heat exchange pipeline is connected to the inside of the anaerobic reactor body, and the coil heat exchange pipeline is spirally arranged in the middle and lower part of the anaerobic reactor body.