A semi-dry anaerobic reactor for kitchen waste

Abstract

This utility model relates to the field of anaerobic reactor technology, specifically to a semi-dry anaerobic reactor for food waste. It includes a prefabricated housing, and within the prefabricated housing are a gas extraction zone, a circulating reaction zone, a gas release device, and a biogas circulation system. It solves the technical problems of large volume, high investment, and high water consumption in current wet anaerobic fermentation reactors for food waste. It also solves the technical problems of low treatment efficiency, low gas production rate, and high investment in current dry anaerobic fermentation reactors for food waste. Furthermore, it solves the technical problems of high mechanical stirring accident rate and difficulty in achieving balanced mixing in current anaerobic fermentation reactors for food waste. Finally, it solves the technical problem of rapid construction in current anaerobic fermentation reactors for food waste.

Description

Technical Field

[0001] This utility model relates to the field of anaerobic reactor technology, specifically to a semi-dry anaerobic reactor for kitchen waste. Background Technology

[0002] With the acceleration of urbanization, the problem of urban domestic waste disposal is becoming increasingly prominent. Food waste, as a major component of urban domestic waste, presents a dual challenge to traditional landfill and incineration methods due to its high moisture and organic matter content, posing challenges to both environmental protection and resource recovery. Anaerobic digestion technology, as an effective method for treating organic waste, can not only reduce and harmlessly treat waste but also achieve energy reuse through the recovery of biogas (mainly methane). However, existing wet (food waste) and dry (kitchen waste) anaerobic digestion technologies have limitations in terms of treatment efficiency, system stability, and equipment complexity. Semi-dry anaerobic digestion combines the advantages of wet and dry anaerobic fermentation, requiring less water, producing a high biogas yield per unit area, and producing low moisture content in the digestate. This effectively solves the water consumption problem and subsequent treatment challenges of traditional processes. The mixed fermentation of two substrates simplifies the substrate treatment process and improves system operating efficiency. Technological innovation is urgently needed to improve treatment efficiency and reduce operating costs. Utility Model Content

[0003] In view of the above-mentioned shortcomings of the existing technology, the present invention provides a semi-dry anaerobic reactor for kitchen waste, which can effectively solve the problems of low processing efficiency, poor system stability and complex equipment in the existing technology.

[0004] To achieve the above objectives, this utility model provides the following technical solution:

[0005] This utility model provides a semi-dry anaerobic reactor for kitchen waste, including a prefabricated housing, and further comprising:

[0006] The prefabricated enclosure is equipped with a gas extraction zone, a circulating reaction zone, a gas release device, and a biogas circulation system.

[0007] Furthermore, the prefabricated box includes multiple wall panels, which are connected by bolts.

[0008] Furthermore, the wall panel is trapezoidal in shape and has folded edges at both the top and bottom along the trapezoidal extension direction. The folded edges are provided with bolt holes, and the upper and lower wall panels are respectively sealed and fixed to the irregular parts by bolts. Irregular parts are provided at both ends along the trapezoidal extension direction, and the irregular parts are also provided with bolt holes, which can be sealed and fixed to the left and right wall panels by bolts.

[0009] Furthermore, the biogas circulation system includes a perforated mixing pipe and an explosion-proof blower. The explosion-proof blower collects biogas, pressurizes it, and circulates it into the perforated mixing pipe. The explosion-proof blower is also equipped with a PLC control system that automatically adjusts the circulating gas volume of the explosion-proof blower according to the biogas flow rate.

[0010] Furthermore, the prefabricated housing is equipped with an anaerobic reactor, which includes multiple independent reaction units. Each independent reaction unit consists of a single air-lift zone and a single circulating reaction zone, and the independent reaction units are connected in series.

[0011] Furthermore, the independent reaction unit is provided with a partition that is straight at the top and inclined at the bottom, and the independent reaction unit is divided into an independent gas stripping zone and a circulating reaction zone by the partition that is straight at the top and inclined at the bottom.

[0012] Furthermore, the biogas released from the bottom perforated mixing tube is collected by the baffle plate in the gas-lift zone, which is straight at the top and inclined at the bottom. At the same time, a portion of the mud-water mixture in the gas-lift zone is lifted and pushed to the next independent reaction unit, until it is circulated back to the first independent reaction unit with the feed inlet.

[0013] Furthermore, another portion of the mud-water mixture in the air-lift zone is lifted to the circulating reaction zone, and the air-lift zone and the circulating reaction zone continuously cycle and react.

[0014] The technical solution provided by this utility model has the following advantages compared with the known prior art:

[0015] 1. It solves the technical problems of large volume, high investment and high water consumption of existing wet anaerobic fermentation reactors for kitchen waste.

[0016] 2. It solves the technical problems of low processing efficiency, low gas production rate and high investment in existing dry anaerobic fermentation reactors for kitchen waste.

[0017] 3. It solves the technical problems of high mechanical stirring accident rate and difficulty in achieving balanced mixing in existing anaerobic fermentation reactors for kitchen waste.

[0018] 4. It solved the technical problem of rapid construction of existing anaerobic fermentation reactors for kitchen waste. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1A schematic diagram of the structural components of the assembled wall panel for an anaerobic reactor;

[0021] Figure 2 This is a schematic diagram showing the relationship between the water flow directions in the different functional zones of an anaerobic reactor.

[0022] Figure 3 This is a schematic diagram of the internal structure and working principle of an anaerobic reactor.

[0023] The labels in the diagram represent: 1-Box plate; 1-1 Trapezoidal bent plate; 1-2 Irregular part; 2-Gas release device; 2-1 Vertical plate; 2-2 Reflective cone; 3-Tube-type gas lifting device; 3-1 Gas lifting pipe; 3-2 Sealing sleeve; 3-3 Gas supply pipe; 4-Circulating reaction partition wall; 5-Reaction zone partition wall; 6-Perforated mixing pipe; 7-Discharge pipe; 8-Explosion-proof fan; 9-Biogas flow meter; 10-Bolt. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0025] The present invention will be further described below with reference to the embodiments.

[0026] Example: A semi-dry anaerobic reactor for kitchen waste includes a prefabricated box, and the prefabricated box is equipped with a gas lift zone, a circulating reaction zone, a gas release device, and a biogas circulation system.

[0027] For prefabricated enclosures, it is preferable to choose removable wall panels with bolt-like connections.

[0028] Specifically, the prefabricated box wall panel has folded edges at the top and bottom along the trapezoidal extension direction, and bolt holes on the folded edges. The upper and lower wall panels are respectively sealed and fixed to the irregular parts by bolts. Irregular parts are provided at both ends along the trapezoidal extension direction, and the irregular parts are also provided with bolt holes, which can be sealed and fixed to the left and right wall panels by bolts.

[0029] The biogas circulation system mainly includes a perforated stirring pipe for pressurizing and circulating the biogas collected in the reactor to the bottom. The explosion-proof blower also needs to be equipped with a PLC control system that can automatically adjust the circulating gas volume based on the biogas flow rate.

[0030] An anaerobic reactor is composed of multiple interconnected units, each consisting of a single air-lift zone and a single circulating reaction zone. Each independent reaction unit is divided into an air-lift zone and a circulating reaction zone by a baffle plate that is straight at the top and sloping at the bottom. All biogas released from the bottom perforated agitator is collected, creating an air-lift phenomenon that lifts a portion of the sludge-water mixture from the air-lift zone and pushes it to the next reaction unit. The next reaction unit also experiences air-lifting, sequentially lifting a portion of the sludge-water mixture from its air-lift zone to the next reaction unit, until it can be circulated back to the first reaction unit with the feed inlet. The remaining sludge-water mixture from the air-lift zone is lifted to the circulating reaction zone by a tubular air-lift mechanism, achieving a continuous cyclic reaction between the air-lift and circulating reaction zones.

[0031] A ramp needs to be installed at the bottom of the circulating reaction zone to guide the mud-water mixture from the circulating reaction zone into the gas-lift zone, achieving a reciprocating cycle between the gas-lift zone and the circulating reaction zone. Both the feed inlet and sampling inlet need to be equipped with gas release devices. The gas release system consists of a vertical plate and a reflective cone. The top of the anaerobic reactor needs to be sealed and equipped with a biogas outlet pipe. The biogas output from the outlet pipe needs to be connected to the inlet of an explosion-proof blower. The outlet of the explosion-proof blower needs to be connected to the perforated pipe at the bottom of the anaerobic reactor via a duct-type gas lift system. A biogas flow meter needs to be installed on the pipe connecting the biogas output from the outlet pipe to the inlet of the explosion-proof blower for interlocking with the PLC, allowing for automatic adjustment of the gas supply based on the gas production rate.

[0032] As attached Figure 1 As shown in the left view, the tank wall of the prefabricated anaerobic reactor of this invention is composed of a trapezoidal bent plate (1-1) and two irregularly shaped parts coupled together. As shown in the top view, the trapezoidal bent plate, perpendicular to its propagation direction, has two irregularly shaped parts at each end, and these parts are equipped with bolts for connection to adjacent left and right side panels. As shown in the side view, two folded edges parallel to the propagation direction of the trapezoidal bent plate are respectively equipped with bolts connecting to the upper and lower wall panels. Therefore, the wall panels of the prefabricated anaerobic reactor of this invention are sealed to the upper and lower or left and right side wall panels respectively through the upper and lower folded edges of the trapezoidal bent plate and the bolts provided on the left and right irregularly shaped parts.

[0033] As attached Figure 2 As shown: The prefabricated anaerobic reactor of this utility model has four independent reaction units inside. Each independent reaction unit is separated from the others by a 5-reaction zone partition wall and operates independently. Each independent reaction unit is composed of a gas stripping zone and a circulation reaction zone. The top of each unit is equipped with a biogas outlet pipe, a feed inlet, and a sampling port.

[0034] As attached Figure 3 As shown: The feed first enters the channel between the vertical plate 2-1 of the 2-release device and the tank wall in the first reaction zone. Then, under the action of gravity, it slides down along the 2-2 reflective cone of the 2-release device to the air-lift zone of the first reaction zone. There, under the gas stirring action of the 6-perforated stirring tube at the bottom of the first reaction zone, it is thoroughly mixed with the anaerobic sludge in the air-lift zone. Afterwards, it is lifted to the circulating reaction zone of the first reaction zone by the 3-tube air-lift device. The gas released from the 6-perforated stirring tube at the bottom of the air-lift zone changes direction upon encountering the 2-2 reflective cone of the 2-release device, moving away from the open area at the top and being completely collected by the air chamber at the top. Therefore, this provides a safety guarantee for the safe operation of the feed inlet under open conditions. Figure 3 As shown, a 4-circulation reaction partition wall, sloping downwards from top to bottom, is installed between the gas-lifting zone and the circulation reaction zone in the first reaction zone. The 4-circulation reaction partition wall is designed with a top-down sloping structure to fully utilize the top-narrow, bottom-wide shape created by the sloping wall. This structure facilitates the collection of all gas released from the 6-perforated stirring tube at the bottom of the first reaction zone into the gas-lifting zone, thus achieving gas lift. Combined with... Figure 2 As shown, we can see that a portion of the mud-water mixture in the first reaction zone's air-lift area, driven by the air-lift force generated in the first reaction zone, enters the circulating reaction zone of the second reaction zone. Similarly, the air-lift force generated in the second reaction zone can then lift a portion of the mud-water mixture from the air-lift area to the circulating reaction zone of the third reaction zone, and so on, until the air-lift force generated in the fourth reaction zone lifts a portion of the mud-water mixture from the air-lift area of ​​the fourth reaction zone back to the circulating reaction zone of the first reaction zone, thus continuously repeating the cycle. Figure 3 As shown, we can also see that, in order to better improve the reaction efficiency of the anaerobic reaction zone of this invention, another part of the mud-water mixture in the air-lift zone of the first reaction zone is lifted to the circulating reaction zone by the 3-tube air-lift device. Since the mud-water mixture entering the circulating reaction zone moves continuously downwards under the action of gravity, the energy consumption of stirring in the circulating reaction zone can be eliminated, achieving low-energy consumption and carbon-reducing operation. In addition, combined with Figure 2 We can also see that each of the first, second, third, and fourth reaction zones has its own independent gas-lifting zone and circulation reaction zone. The fourth reaction zone is the reaction terminal of this anaerobic reactor, and therefore, as shown in the figure, it also needs to be equipped with a sampling port to facilitate daily monitoring of the reactor's operating status. A 2-gas release device still needs to be installed below the sampling port. This ensures that even with the sampling port open, no biogas will be released into the air, greatly guaranteeing the safe daily operation of the anaerobic reactor.

[0035] like Figure 3 As shown, the biogas collected at the top of the anaerobic reactor of this invention is transported through the top outlet pipe to the inlet of the explosion-proof blower via the 9-biogas flow meter. The biogas, pressurized and compressed by the 8-explosion-proof blower, provides the gas power source for the 3-tube gas lift device and the 6-perforated stirring pipe of the anaerobic reactor of this invention. To maximize the stirring effect and reduce daily operation, this invention also requires interlocking between the 9-biogas flow meter and the PLC control cabinet to achieve automatic adjustment of the biogas output circulation volume based on the biogas production. Normally, when the biogas production of the anaerobic reactor of this invention is high, the upward flow velocity of the gas and liquid increases, thus the output circulation volume of the 8-explosion-proof blower can be reduced accordingly. Conversely, if the biogas production is low, automatic biogas output circulation volume is required to ensure the mass transfer effect of mud-water mixing and sufficient circulation volume of the 3-tube gas lift device.

[0036] Therefore, it is evident that this utility model, through the aforementioned systematic design, achieves a fully sealed connection, enabling the anaerobic reactor to be modularly designed. This facilitates standardized factory prefabrication and on-site skid-mounted connection, significantly simplifying construction, shortening the construction cycle, improving project efficiency, reducing costs, and promoting green, carbon-reducing, and sustainable development. Furthermore, it provides a novel solution for food waste treatment, improving processing efficiency and reducing investment and operating costs.

[0037] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of this utility model.

Claims

1. A semi-dry kitchen waste anaerobic reactor comprising a fabricated box, characterized in that, Also includes: The prefabricated enclosure is equipped with a gas extraction zone, a circulating reaction zone, a gas release device, and a biogas circulation system.

2. The semi-dry kitchen waste anaerobic reactor according to claim 1, characterized in that, The prefabricated box includes multiple wall panels, which are connected by bolts.

3. The semi-dry kitchen waste anaerobic reactor according to claim 2, characterized in that, The wall panel is trapezoidal in shape and has folded edges at both the top and bottom along the trapezoidal extension direction. The folded edges are provided with bolt holes. The upper and lower wall panels are respectively sealed and fixed to the irregular parts by bolts. Irregular parts are provided at both ends along the trapezoidal extension direction, and the irregular parts are also provided with bolt holes. They can be sealed and fixed to the left and right wall panels by bolts.

4. The semi-dry kitchen waste anaerobic reactor according to claim 1, characterized in that, The biogas circulation system includes a perforated mixing pipe and an explosion-proof blower. The explosion-proof blower collects biogas, pressurizes it, and circulates it into the perforated mixing pipe. The explosion-proof blower is also equipped with a PLC control system that automatically adjusts the circulating gas volume of the explosion-proof blower according to the biogas flow rate.

5. The semi-dry kitchen waste anaerobic reactor according to claim 1, characterized in that, The prefabricated enclosure contains an anaerobic reactor, which includes multiple independent reaction units. Each independent reaction unit consists of a single air-lift zone and a single circulating reaction zone, and the independent reaction units are connected in series.

6. The semi-dry kitchen waste anaerobic reactor according to claim 5, characterized in that, The independent reaction unit is equipped with a partition that is straight at the top and inclined at the bottom, which divides the independent reaction unit into an independent gas stripping zone and a circulating reaction zone.

7. The semi-dry kitchen waste anaerobic reactor according to claim 6, characterized in that, The biogas released from the bottom perforated mixing pipe is collected by the baffle plate in the gas-lift zone, which is straight at the top and sloping at the bottom. At the same time, a portion of the mud-water mixture in the gas-lift zone is lifted and pushed to the next independent reaction unit, until it is circulated back to the first independent reaction unit with the feed inlet.

8. The semi-dry kitchen waste anaerobic reactor according to claim 7, characterized in that, Another portion of the mud-water mixture in the air-lift zone is lifted to the circulating reaction zone, and the air-lift zone and the circulating reaction zone continuously cycle and react.

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