Microbial fuel cell self-purification type constructed wetland with backwashing system
By introducing a backwashing system and a conductive packing layer design into the constructed wetland-microbial fuel cell system, the problem of matrix layer blockage was solved, achieving stable system operation and efficient wastewater treatment, while also improving the energy recovery capacity.
Patent Information
- Application Number
- CN202423118036.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-12-17
AI Technical Summary
In existing constructed wetland-microbial fuel cell systems, the matrix layer is prone to physical blockage, leading to system instability and affecting wastewater treatment efficiency and energy recovery.
A backwashing system is introduced into the system to clean the matrix layer with high-pressure water flow. Combined with the conductive filler layer design of pyrite and activated carbon, electron transfer and biofilm degradation are promoted. At the same time, soilless potted plants are used to grow wetland plants to reduce backwashing resistance.
It effectively prevents the substrate layer from clogging, ensures the long-term stable operation of the system and the quality of the effluent, improves the efficiency of sewage treatment and the ability to recover electricity, and simplifies system maintenance.
Smart Images
Figure CN223576262U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of sewage treatment, and relates to a constructed wetland, in particular to a self-purification type constructed wetland with a backwashing system of microbial fuel cell. BACKGROUND
[0002] In order to deal with the problem of water resources and energy depletion, people adopt the technology of sewage treatment and energy recovery, and the constructed wetland (CW) based on natural wetland ecological system becomes a new sewage treatment process, which has the characteristics of low investment, low energy consumption and remarkable ecological benefits. Plant absorption, substrate adsorption and microbial degradation are the main action modes for removing pollutants in CW. However, the substrate layer is blocked after long-term operation, which limits its further application.
[0003] According to different causes of blockage, CW blockage is mainly divided into physical, chemical and biological blockage. Compared with physical and chemical blockage, biological blockage is more common and more difficult to alleviate. Biological blockage is mainly caused by the accumulation of a large number of microorganisms and extracellular polymeric substances (EPS) produced in the metabolic process of microorganisms on the surface of the substrate. As an important bioelectrochemical system, microbial fuel cell (MFC) can recover electrical energy from wastewater treatment through electrochemically active bacteria (EAB). Recently, the microbial fuel cell (MFC) is embedded in the CW to construct a constructed wetland-microbial fuel cell (CW-MFC) coupling system, which provides a strategy for strengthening wastewater treatment and alleviating biological blockage. The microelectric field existing in the MFC helps to change the characteristics of EPS and accelerate the directional migration of negatively charged particles to the anode, and promote the enrichment of electrogenic bacteria (EAB) on the electrode to enhance electron transfer, thereby strengthening the degradation of EPS and alleviating biological blockage.
[0004] However, in actual engineering, physical blockage is dominant, which is mainly caused by the deposition of suspended particles and refractory organic matter on the surface of the constructed wetland, the plant produced debris, the organic and inorganic suspended particles in the substrate, and the refractory organic matter. SUMMARY
[0005] In order to efficiently treat wastewater to obtain electrical energy and solve the problem of substrate layer blockage of constructed wetland-microbial fuel cell, the utility model discloses a self-purification type constructed wetland with a backwashing system of microbial fuel cell.
[0006] TECHNICAL SCHEME
[0007] The utility model discloses a kind of microbial fuel cell self-cleaning type constructed wetland with backwash system, including reactor body, the reactor body is sequentially provided with first filter filler layer, second filter filler layer, pyrite filler layer, third filter filler layer and activated carbon filler layer from bottom to top;Wherein: anode is buried in the pyrite filler layer, cathode is located the surface of activated carbon filler layer;Backwash pipe is laid between the pyrite filler layer and third filter filler layer and is connected with pump and extends reactor body, the backwash pipe is evenly provided with a plurality of filter heads, the filter head is buried in third filter filler layer, and the pump supplies water to flush third filter filler layer and activated carbon filler layer;The bottom side wall of the reactor body is equipped with inlet pipe, the inlet pipe is laid in the first filter filler layer, and the surface is evenly provided with water distribution branch pipe, and the water distribution branch pipe is provided with water distribution hole;The upper side wall of the reactor body is equipped with outlet pipe.
[0008] The utility model discloses a more preferably disclosed example, the gravel particle size in the first filter filler layer is 20~30mm, and the filling height is 20~25cm;The gravel particle size in the second filter filler layer is 15~20mm, and the filling height is 15~20cm.
[0009] The utility model discloses a more preferably disclosed example, the particle size in the pyrite filler layer is 5~12mm, and the filling height is 15~20cm.
[0010] The utility model discloses a more preferably disclosed example, the sand filter material particle size in the third filter filler layer is 2~4mm, and the filling height is 20~25cm.
[0011] The utility model discloses a more preferably disclosed example, the particle size in the activated carbon filler layer is 4~8mm, and the filling height is 10~15cm.
[0012] The utility model discloses a more preferably disclosed example, the anode and cathode are all formed by two layers of stainless steel wire mesh and graphite carbon felt that is clamped between two layers of stainless steel wire mesh, and the surface of the stainless steel wire mesh is provided with hole, and the diameter is 2~4cm.
[0013] The utility model discloses a more preferably disclosed example, the anode and cathode are connected into closed loop through wire and resistor.
[0014] Further, the wire is copper wire, and the insulating layer wrapped outside is an epoxy resin layer.
[0015] The utility model discloses a more preferably disclosed example, still includes support, the support is located the cathode on, and is located the top of reactor body, and leave the gap with the cathode, and be equipped with soilless pot on the support, and the wetland plant is planted in the soilless pot.
[0016] Further, the root system of the wetland plant is soaked in water surface surface layer, and the soilless pot contains ceramsite filler.
[0017] The reactor is in the shape of a cuboid, the flow direction is vertically upward, wastewater enters through the bottom inlet pipe, is evenly distributed through the distribution branch pipe, and then flows upward for filtration, and the suspended solids in the wastewater are gradually removed through gravel, sand filter material and activated carbon filler in turn. The wastewater passes through the anode area, the electroactive microorganisms oxidize organic matter to produce electrons under anaerobic conditions, and then the electrons are transmitted to the cathode in the aerobic environment through the copper wire conductor and combined with the electron acceptor (such as oxygen secreted by the wetland plant root system) to occur reduction reaction, and this process realizes the output of electric current. Pyrite has the characteristics of strong conductivity, and the anode is arranged between pyrite, which promotes autotrophic denitrification and phosphorus precipitation. On the other hand, activated carbon also has conductivity, which improves the power generation capacity of the microbial fuel cell. After the coupled system is operated for a long time, the matrix layer will inevitably be blocked due to the aggregation of biofilm, the growth and metabolism of plant roots, and the blockage of inorganic particles. The artificial wetland-microbial fuel cell coupled system itself has the function of relieving biological blockage, but in practice, the main reason for the blockage is physical blockage. After the system is operated for a period of time, the water pump is started, and the water flow with high water pressure is used to backwash the matrix layer, and the impure water is discharged from the reactor through the outlet pipe. Among them, the wetland plants are soilless cultured, which can effectively reduce the backwashing resistance. The high-efficiency wastewater treatment obtains electric energy, solves the problem of blockage of the matrix layer of the artificial wetland-microbial fuel cell, realizes the long-term stable operation of the system, and guarantees the water quality of the effluent.
[0018] Advantages
[0019] The microbial fuel cell self-cleaning type artificial wetland with a backwashing system provided by the utility model strengthens wastewater treatment through the constructed artificial wetland-microbial fuel cell coupled system, improves the sewage treatment efficiency, prevents the blockage of the artificial wetland-microbial fuel cell coupled system caused by long-term operation through the addition of the backwashing pipeline in the matrix layer, guarantees the stable operation of the system and the water quality of the effluent, and in addition, the wetland plants are replaced by traditional sand soil planting through soilless potting, the backwashing resistance is reduced, and the system is convenient to maintain. ACCURACY
[0020] Figure 1 . A structural schematic view of a microbial fuel cell self-cleaning type artificial wetland with a backwashing system;
[0021] Figure 2 . A top view schematic view of a microbial fuel cell self-cleaning type artificial wetland with a backwashing system;
[0022] Wherein, the reference sign: 1, water inlet pipe;2, water distribution branch;3, the first filter filler layer;4, the second filter filler layer;5, pyrite filler layer;6, anode;7, backwash pipe;8, filter head;9, pump;10, the third filter filler layer;11, activated carbon filler layer;12, water outlet pipe;13, cathode;14, support;15, soilless potting;16, wetland plants;17, wire;18, resistor. DETAILED DESCRIPTION
[0023] The utility model will be explained in detail below combining with the embodiment, so that the person skilled in the art better understands the utility model, but the utility model is not limited to the following embodiment.
[0024] Please refer to Figure 1 、 Figure 2 As shown in the figure, a kind of microbial fuel cell self-purification type artificial wetland with backwash system, including reactor body, the reactor body is sequentially provided with first filter filler layer 3 from bottom to top, the gravel particle size in the first filter filler layer 3 is 20~30mm, and filling height is 20~25cm;Second filter filler layer 4, the gravel particle size in the second filter filler layer 4 is 15~20mm, and filling height is 15~20cm;Pyrite filler layer 5, the particle size in the pyrite filler layer 5 is 5~12mm, and filling height is 15~20cm;The third filter filler layer 10, the sand filter material particle size in the third filter filler layer 10 is 2~4mm, and filling height is 20~25cm;And activated carbon filler layer 11, the particle size in the activated carbon filler layer 11 is 4~8mm, and filling height is 10~15cm;Wherein: anode 6 is buried in the pyrite filler layer 5, and cathode 13 is arranged on the surface of activated carbon filler layer 11;Backwash pipe 7 is laid between pyrite filler layer 5 and third filter filler layer 10 and extends reactor body and is connected with pump 9, a plurality of filter heads 8 are evenly arranged on the backwash pipe 7, the filter head 8 is buried in the third filter filler layer 10, and the pump 9 supplies water to flush third filter filler layer 10 and activated carbon filler layer 11;The bottom side wall of the reactor body is equipped with water inlet pipe 1, the water inlet pipe 1 is laid in the first filter filler layer 3, and the surface is evenly equipped with water distribution branch 2, the water distribution branch 2 is equipped with water distribution hole;The upper side wall of the reactor body is equipped with water outlet pipe 12.
[0025] In the microbial fuel cell self-purification type artificial wetland with backwash system, anode 6 and cathode 13 are both composed of two layers of stainless steel wire mesh and graphite carbon felt sandwiched between the two layers of stainless steel wire mesh, the surface of the stainless steel wire mesh is provided with holes, and the diameter is 2~4cm;And, the anode 6 and cathode 13 are connected into closed loop by wire 17 and resistor 18, wherein the wire 17 is copper wire, and the insulating layer wrapped outside is epoxy resin layer.
[0026] The self-cleaning type constructed wetland with the microbial fuel cell with backwashing system further comprises a support 14 arranged above the cathode 13, located at the top of the reactor body, leaving a gap with the cathode 13, and a soilless pot 15 is arranged on the support 14, wherein the wetland plant 16 is planted.
[0027] The above describes one embodiment of the present application in detail, describes the basic principle, main features and advantages of the present application, but the content is only the preferred embodiment of the present application. For ordinary skilled in the art, it can be understood that without departing from the principles and spirit of the present application, various changes, modifications, replacements and modifications can be made to these embodiments, and these changes and improvements should still belong to the patent coverage range of the present application.
Claims
1. A self-purifying constructed wetland with a microbial fuel cell and a backwashing system, comprising a reactor body, wherein the reactor body is provided with, from bottom to top, a first filter media layer (3), a second filter media layer (4), a pyrite media layer (5), a third filter media layer (10), and an activated carbon media layer (11); characterized in that: The anode (6) is embedded in the pyrite packing layer (5), and the cathode (13) is located on the surface of the activated carbon packing layer (11). The backwash pipe (7) is laid between the pyrite packing layer (5) and the third filter packing layer (10) and extends out of the reactor body to be connected to the pump (9). Several filter heads (8) are evenly arranged on the backwash pipe (7). The filter heads (8) are embedded in the third filter packing layer (10). The pump (9) supplies water to rinse the third filter packing layer (10) and the activated carbon packing layer (11). The bottom side wall of the reactor body is provided with a water inlet pipe (1). The water inlet pipe (1) is laid in the first filter packing layer (3). Its surface is evenly provided with water distribution branch pipes (2). The water distribution branch pipes (2) are provided with water distribution holes. The upper side wall of the reactor body is provided with a water outlet pipe (12).
2. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: The gravel particle size in the first filter media layer (3) is 20-30 mm and the filling height is 20-25 cm; the gravel particle size in the second filter media layer (4) is 15-20 mm and the filling height is 15-20 cm.
3. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: The pyrite filler layer (5) has a particle size of 5-12 mm and a filling height of 15-20 cm.
4. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: The sand filter media in the third filter media layer (10) has a particle size of 2-4 mm and a filling height of 20-25 cm.
5. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: The particle size of the activated carbon filler layer (11) is 4-8 mm, and the filling height is 10-15 cm.
6. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: Both the anode (6) and the cathode (13) are composed of two layers of stainless steel wire mesh and graphite carbon felt sandwiched between the two layers of stainless steel wire mesh. The stainless steel wire mesh has holes with a diameter of 2 to 4 cm on its surface.
7. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 1, characterized in that: The anode (6) and cathode (13) are connected to the resistor (18) via wire (17) to form a closed circuit.
8. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 7, characterized in that: The conductor (17) is a copper wire, and the outer insulating layer is an epoxy resin layer.
9. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to any one of claims 1-8, characterized in that: It also includes a support (14), which is located on the cathode (13) at the top of the reactor body and has a gap with the cathode (13). A soilless potted plant (15) is provided on the support (14), in which wetland plants (16) are planted.
10. The self-purifying constructed wetland with microbial fuel cell and backwashing system according to claim 9, characterized in that: The roots of the wetland plant (16) are submerged in the surface of the water, and the soilless potted plant (15) is filled with ceramsite.