CN115286120A

CN115286120A - Electrode type artificial ecological floating island device and method for synchronously repairing water body and bottom mud

Info

Publication number: CN115286120A
Application number: CN202210960471.1A
Authority: CN
Inventors: 蒋晴; 薛建良; 史可; 马菡; 乔延路; 高宇; 王坤华; 王浩; 鲁浩蕴
Original assignee: Shandong University of Science and Technology
Current assignee: Shandong University of Science and Technology
Priority date: 2022-08-11
Filing date: 2022-08-11
Publication date: 2022-11-04
Anticipated expiration: 2042-08-11
Also published as: CN115286120B

Abstract

The invention discloses an electrode type artificial ecological floating island device and a method for synchronously repairing water and bottom mud, and belongs to the technical field of water body repair. The electrode type artificial ecological floating island device comprises a three-dimensional anode system embedded in bottom mud, a three-dimensional cathode system floating on the water surface, and a lead and a resistor for connecting the three-dimensional anode system and the three-dimensional cathode system; the device can be arranged in a water body to be treated to restore the water body and the bottom mud. The device increases the dissolved oxygen content of the water body by establishing the cathode electrode cultured with aquatic plants, and couples the artificial ecological floating island with the sediment microbial fuel cell, thereby realizing the synchronous restoration of the black and odorous water body and the bottom mud; in addition, the traditional two-dimensional planar anode is changed into a three-dimensional structure, and low-cost natural conductive pyrite is introduced as an anode filler, so that the effective area of the anode electrode is enlarged, and the repair effect is effectively promoted.

Description

Electrode type artificial ecological floating island device and method for synchronously repairing water body and bottom mud

Technical Field

The invention belongs to the technical field of water body restoration, and particularly relates to an electrode type artificial ecological floating island device and a method for synchronously restoring water body and bottom mud.

Background

With the continuous acceleration of the industrialization process and the continuous improvement of the economic level, a large amount of sewage and wastewater is randomly discharged, which causes the problems of water eutrophication, blackening, smelliness and the like, and directly influences the life quality of nearby residents. At present, a plurality of methods for treating black and odorous water bodies exist: for example, the black and odorous water body is improved by controlling an external pollution source, or the black and odorous water body is subjected to in-situ water ecological remediation through an artificial ecological floating island, but the black and odorous bottom mud at the bottom cannot be fundamentally treated.

In addition, the sediment microbial fuel cell is a bioelectrochemical technology for in-situ remediation of sediment, and the action principle of the sediment microbial fuel cell is that an anode is placed in anaerobic sediment, electroactive bacteria attached to an anode electrode can degrade organic pollutants in the sediment, generated electrons are transferred to a cathode in an upper water body through an external circuit, oxygen at the cathode is combined with electrons and protons transferred by the anode to generate water, and then the organic pollutants in the sediment are removed while energy is recovered. However, the sediment microbial fuel cell is faced with two problems when applied to large-scale engineering: (1) The sediment microbial fuel cell is likely to cause the reduction of the electrode area ratio due to the enlargement, the efficiency of the electroactive process is low, and the traditional electrode enlargement means the multiplication of the construction cost and is not beneficial to the engineering popularization; (2) The black and odorous water body has low dissolved oxygen content and poor reoxygenation capability, so that an artificial aeration mode is usually adopted to provide oxygen for the cathode in the practical application process, and the energy consumption is increased.

Disclosure of Invention

Aiming at the problems, the invention provides an electrode type artificial ecological floating island device and a method for synchronously restoring water and bottom mud.

The electrode type artificial ecological floating island device comprises a three-dimensional anode system embedded in bottom mud, a three-dimensional cathode system floating on the water surface, and a lead and a resistor for connecting the three-dimensional anode system and the three-dimensional cathode system;

the three-dimensional anode system comprises a plurality of anode support plates, a three-dimensional grid-shaped structure is formed among the anode support plates, each grid forms an anode cavity, and an anode electrode is filled in each anode cavity;

the three-dimensional cathode system comprises a plurality of cathode supporting plates, a three-dimensional grid-shaped structure is formed among the plurality of cathode supporting plates, each grid forms a cathode cavity, and cathode electrodes are filled in the cathode cavities;

the three-dimensional cathode system also comprises a floating body which is used for supporting the cathode supporting plates and enabling the cathode supporting plates to float on the water surface, a space formed by the floating body and the cathode cavity is filled with a matrix material, and aquatic plants are planted on the matrix material.

Wherein, the anode electrode and the cathode electrode are made of carbon materials, metal materials or conductive polymer materials; the anode supporting plate and the cathode supporting plate are both made of non-conductive insulating materials;

the device is arranged in a water body to be treated, the three-dimensional anode system is embedded in anoxic water body sediment, the three-dimensional cathode system floats on the surface of the water body, a lead is communicated with an anode material of the three-dimensional anode system and a cathode material of the three-dimensional cathode system, and a resistor is connected on the lead to form a closed loop. Under the action of the anaerobic microorganisms in the sediment, the organic matters in the sediment of the water body are metabolized and decomposed by the anaerobic microorganisms, electrons are generated, and the electrons can pass through cell membranes and are transmitted to an extracellular anode electrode, namely the anode is used as a solid electron acceptor of the anaerobic microorganisms, and the electron transmission process is also realized. The anode electrons are then transferred to the cathode through an external circuit (i.e., a wire and resistor). The cathode is positioned on the surface of the water body, the aquatic plants planted in the three-dimensional cathode system perform photosynthesis under the illumination of the sun to release oxygen, the oxygen receives electrons transmitted from the anode and performs reduction reaction to generate water, and therefore the electricity generation process is completed, in the process, organic pollutants in the sediment are degraded, and current is synchronously generated. Besides, the three-dimensional cathode system can also synchronously realize water body purification: aquatic plants in the three-dimensional cathode system and microorganisms attached to the surfaces of a substrate material, a cathode electrode, a floating body, a plant root system and the like can degrade and absorb pollutants in a part of water body; meanwhile, the growth of the aquatic plants can shield the sunlight on the water surface, so that the photosynthesis of algae is inhibited, and the possibility of eutrophication of the water body is reduced.

On the basis, the device also comprises a conductive metal material; the conductive metal material connects the anode electrodes in each anode cavity or the cathode electrodes in each cathode cavity in series, and then connects the anode electrodes in different anode cavities or the cathode electrodes in different cathode cavities in series. The structure converts a single anode into a three-dimensional multi-anode structure, and converts a single cathode into a three-dimensional multi-cathode structure, so that the three-dimensional anode greatly improves the surface area of the anode, provides more attachment sites for anode electroactive bacteria, and plays a certain role in fixing bottom mud; compared with the traditional one-piece cathode, the three-dimensional cathode is more beneficial to capturing oxygen to generate oxygen reduction action and is beneficial to the restoration effect of the water body.

On the basis, the bottom of the anode cavity is provided with an anode strengthening material. The anode strengthening material is pyrite. Pyrite low cost, be convenient for acquire to because pyrite releases Fe (III) in oxidation process, and Fe (III) can promote electron transfer process, thereby further promote the electroactive process of positive pole, further enlarge the positive pole scope to the region beyond the anode electrode, accelerate the repair process to the bed mud, thereby improve organic pollutant's degradation effect in the bed mud.

On the basis, the device also comprises a fixed support for fixing the three-dimensional cathode system, and the bottom of the fixed support is fixed in the bottom mud. Because the three-dimensional cathode system floats on the water surface, the three-dimensional cathode system can be positioned at a relatively determined position by the structure, so that the observation, the detection and the maintenance are convenient, and the three-dimensional anode system and the three-dimensional cathode system are connected only by the lead, so that the overall stability of the microbial fuel cell can be improved by the fixing bracket.

As a specific scheme, the fixing bracket comprises a plurality of fixing rods, and each fixing rod comprises a first rod body and a second rod body; one end of the second rod body is inserted into the first rod body, and the second rod body can move along the direction of the first rod body; the end of the second rod body, which is far away from the first rod body, is fixedly connected with the floating body, and the end of the first rod body, which is far away from the second rod body, is fixed in the sediment. Because the aquatic plant needs to satisfy specific growing environment, three-dimensional cathode system need float on the surface of water all the time, and the second body of rod of this kind of fixed bolster can be along with the water motion and move about from top to bottom to make three-dimensional cathode system can rise or descend along with the water level under the effect of gravity and buoyancy, ensure that it floats on the surface of water all the time.

The electrode type artificial ecological floating island device is arranged in a water body to be treated, and the method is used for synchronously purifying and restoring the black and odorous water body and the bottom mud.

As a specific scheme, the method is realized by the following steps: firstly, embedding an anode reinforcing material in bottom mud 15cm below a mud-water interface, and placing a three-dimensional anode system above the anode reinforcing material; then floating the three-dimensional cathode system on the water surface, and installing fixing supports around the three-dimensional cathode system to fix the three-dimensional cathode system above the three-dimensional anode system so as to prevent the three-dimensional cathode system from drifting along with water flow; and finally, connecting the three-dimensional anode system and the three-dimensional cathode system through a wire and a resistor to form a closed loop.

The invention has the advantages that: the invention provides an electrode type artificial ecological floating island device suitable for synchronously restoring black and odorous water and bottom mud, which changes a traditional two-dimensional plane anode into a three-dimensional structure, introduces low-price natural conductive pyrite as anode filler, further enlarges the electric activity range of the anode and effectively promotes the restoring effect, and on the other hand, the artificial ecological floating island is coupled with a sediment microbial fuel cell, the restoring effect of the ecological floating island is enhanced by using a bioelectrochemical technology, and oxygen is provided for a bioelectrochemical cathode by using the oxygen secreted by the root system of aquatic plants in the artificial ecological floating island on the surface of the water, so that the synchronous restoration of the bottom mud and the water is realized. The device and the method can be applied to the remediation of polluted surface water bodies such as rivers, lakes, ditches and the like and bottom mud thereof, and have the advantages of low operation cost, simple maintenance and ecological benefit.

Drawings

FIG. 1 is a schematic view of the overall configuration of an apparatus in example 1;

FIG. 2 is a schematic structural view of a three-dimensional anode system described in example 1;

FIG. 3 is a schematic diagram of the structure of the three-dimensional anode system filled with the anode material according to example 1;

FIG. 4 is a schematic structural view of a three-dimensional cathode system described in example 1;

FIG. 5 is a schematic structural diagram of a three-dimensional cathode system filled with a cathode material according to example 1;

FIG. 6 is a graph showing the effect of water purification in example 3;

FIG. 7 is a graph showing the effect of cement remediation in example 3.

Detailed Description

Terms used in the present invention have generally meanings as commonly understood by one of ordinary skill in the art, unless otherwise specified.

The present invention is described in further detail below with reference to specific examples and data. The following examples are intended to illustrate the invention and are not intended to limit the scope of the invention in any way.

Example 1

As shown in fig. 1, an electrode type artificial ecological floating island device comprises a three-dimensional anode system 1 embedded in sediment, a three-dimensional cathode system 2 floating on the water surface, and a lead 3 and a resistor 4 for connecting the three-dimensional anode system 1 and the three-dimensional cathode system 2;

specifically, as shown in fig. 2, the three-dimensional anode system 1 includes a plurality of anode support plates 1-1, the plurality of anode support plates 1-1 are arranged in a staggered manner to form a three-dimensional grid-shaped structure (the grid may be a diamond, a square or a rectangle), each grid is an anode cavity 1-11, and an anode electrode 1-2 is disposed in the anode cavity 1-11, as shown in fig. 3; the anode supporting plates 1-1 can be connected and fixed in a splicing manner, and the anode electrode 1-2 can be attached to the surface of the anode supporting plate 1-1 (namely the inner wall of the anode cavity 1-11) or filled into each grid;

as shown in fig. 4, the three-dimensional cathode system 2 includes a plurality of cathode support plates 2-1, the plurality of cathode support plates 2-1 are arranged in a staggered manner to form a three-dimensional grid-shaped structure (the grid can be a diamond, a square or a rectangle), each grid is a cathode cavity 2-11, and a cathode electrode 2-2 is arranged in each cathode cavity 2-11, as shown in fig. 5; the cathode supporting plates 2-1 can be connected and fixed in a splicing mode, and the cathode electrodes 2-2 can be attached to the surfaces of the cathode supporting plates 2-1 (namely the inner walls of the cathode cavities 2-11) or filled into each grid;

as shown in fig. 4 and 5, the three-dimensional cathode system 2 further includes a floating body 2-3 for supporting the plurality of cathode support plates 2-1 and floating the plurality of cathode support plates 2-1 on the water surface, a space formed by the floating body 2-3 and the cathode cavity 2-11 is filled with a matrix material, and aquatic plants are planted on the matrix material; as a specific scheme, the floating body 2-3 may be made of plastic, foam board, bamboo, wood bar, cane, novel polymer light material (such as polyvinyl chloride foam board, polystyrene foam, phenolic foam, water-soluble polyurethane, polypropylene), etc., and only needs to provide sufficient buoyancy for the three-dimensional cathode system 2 to balance with gravity, so as to float on the water surface; the floating body 2-3 can be fixedly connected with the cathode supporting plate 2-1 by means of screws, binding ropes and the like.

The device is arranged in a water body to be treated, the three-dimensional anode system 1 is buried in anoxic water body sediment, the three-dimensional cathode system 2 floats on the surface of the water body, a lead 3 is communicated with anode materials 1-2 of the three-dimensional anode system 1 and cathode materials 2-2 of the three-dimensional cathode system 2, and a resistor 4 is connected on the lead 3 to form a closed loop. Under the action of the anaerobic microorganisms in the sediment, the organic matters in the sediment of the water body are metabolized and decomposed by the anaerobic microorganisms, and electrons are generated and can pass through cell membranes to be transmitted to the extracellular anode electrode 1-2, namely, the anode is used as a solid electron acceptor of the anaerobic microorganisms, and the electron transmission process is also realized. The anode electrons are then transferred to the cathode through an external circuit (i.e., lead 3 and resistor 4). The cathode is positioned on the surface of the water body, the aquatic plants planted in the three-dimensional cathode system 2 are subjected to photosynthesis under the illumination of the sun to release oxygen, the oxygen receives electrons transmitted from the anode and generates reduction reaction to generate water, and therefore the electricity generation process is completed, in the process, organic pollutants in the bottom sediment are degraded, and current is synchronously generated.

Outside repairing water body sediment, the device can also realize the restoration of black and odorous water body in step: the aquatic plant in the three-dimensional cathode system 2 can assimilate and absorb pollutants such as nitrogen and phosphorus in the water body in the growth process, and microorganisms attached to the surfaces of a substrate material, a cathode electrode, a floating body, a plant root system and the like of the three-dimensional cathode system 2 can also degrade and absorb a part of pollutants. Meanwhile, the growth of the aquatic plants can shield the sunlight on the water surface, so that the photosynthesis of algae is inhibited, and the possibility of eutrophication of the water body is reduced.

In addition, in order to adapt to the growth of aquatic plants, the surfaces of the cathode supporting plate 2-1 and the floating body 2-3 are provided with openings for water flow to pass through, so that the water body can be allowed to flow freely;

the matrix material is used for fixing plants and microorganisms and can be attached to a hanging film; the following materials can be adopted but not limited: one or more of granular materials such as ceramsite, volcanic rock, zeolite, gravel, quartz sand, expanded vermiculite, activated carbon, medical stone, sponge, carbon fiber balls, oyster shells, bio-based materials and the like can be paved in a layer paving mode or a mode of paving after uniform mixing;

the aquatic plants need to be suitable for water culture, the aquatic plants with strong purification capacity and fast growth are selected, and include but are not limited to rice, ryegrass, canna, water bamboo, reed, calamus, cattail, lentinus edodes, juncus roemerianus, eichhornia crassipes, purple yam, cress, water spinach, iris, water lily, and watermifoil, and the like.

In order to make the three-dimensional stereo anode system 1 and the three-dimensional stereo cathode system 2 fully perform their respective functions, the anode support plate 1-1 and the cathode support plate 2-1 are both made of non-conductive insulating materials, including but not limited to: polyethylene, asbestos, rubber plates, wood plates and the like, and can also be one or a combination of more of the polyethylene, the asbestos, the rubber plates, the wood plates and the like. The anode electrode 1-2 and the cathode electrode 2-2 can be made of the following materials: carbon materials, metallic materials, or conductive polymer materials, including, but not limited to: one or more of carbon cloth, carbon felt, carbon brush, carbon nanotube, graphene, graphite felt, graphite plate, graphite rod, graphite particle, granular activated carbon, biochar and the like.

Because the three-dimensional anode system 1 and the three-dimensional cathode system 2 are both of a three-dimensional grid structure, the connection modes between the anode electrodes 1-2 filled in the plurality of anode cavities 1-11 are many, and similarly, the connection modes between the cathode electrodes 2-2 filled in the plurality of cathode cavities 2-11 are also many, here, as shown in fig. 3 and 5, the invention provides a specific implementable scheme: the device further comprises a conductive metal material 5; after the anode electrodes 1-2 in each anode cavity 1-11 or the cathode electrodes 2-2 in each cathode cavity 2-11 are connected in series by the conductive metal material 5, the anode electrodes 1-2 in different anode cavities 1-11 or the cathode electrodes 2-2 in different cathode cavities 2-11 are connected in series. The conductive metal material 5 includes, but is not limited to, one or more of copper wires, titanium mesh, titanium plate, stainless steel mesh, nickel mesh, and the like.

The structure converts a single anode into a three-dimensional multi-anode structure, and converts a single cathode into a three-dimensional multi-cathode structure, so that the three-dimensional anode greatly improves the surface area of the anode, provides more attachment sites for anode electroactive bacteria, and plays a certain role in fixing bottom mud; compared with the traditional one-piece cathode, the three-dimensional cathode is more beneficial to capturing oxygen to generate oxygen reduction action and is beneficial to the restoration effect of the water body.

The connection and arrangement of the conductive metal material 5 will be described in detail by taking an anode as an example, and the connection between different types of anode electrodes 1-2 and the conductive metal material 5 is different:

if the anode electrodes 1-2 are made of flexible materials such as carbon cloth, carbon felt and graphite felt, the conductive metal material 5 can penetrate through the anode electrodes 1-2 to connect the two anode electrodes 1-2 in a manner similar to sewing;

if the anode electrode 1-2 is a carbon plate, a graphite plate, or other plate-like material, the conductive metal material 5 may be sandwiched between the two anode electrode plates to form a sandwich structure, wherein the conductive metal material 5 may be a metal plate or a metal mesh, and is fixed to the two anode electrode plates in a staggered lap joint manner to communicate the two anode electrode plates;

if the anode electrode 1-2 is a granular structure such as activated carbon, granular carbon and the like, a reticular conductive metal material 5 (such as a stainless steel net) is pre-embedded in the granular electrode to increase the contact area and promote the conductivity;

if the anode electrode 1-2 is a brush material such as a carbon brush, a graphite brush and the like, the electrode is prepared by uniformly twisting equal-length carbon fiber wires between two spirally wound titanium wires, so that the electrode is formed by connecting the electrode brushes in series by the titanium wires;

after the anode electrodes 1-2 in the anode cavities 1-11 are connected in series, the anode electrodes 1-2 in the different anode cavities 1-11 can be connected in series by adopting copper wires or titanium wires, and the conductive metal material 5 (such as copper wires or titanium wires) can be connected with the anode electrodes 1-2 by utilizing a soldering tin gun in the connection process. In a preferred embodiment, the anode chambers 1-11 are connected in series in an S-shaped or serpentine path.

The structure of the cathode and the anode is basically similar, and the description is omitted.

On the basis, anode strengthening materials 1-3 are arranged at the bottom of the anode cavities 1-11. The anode reinforcing material 1-3 is pyrite. The length or the particle size of the pyrite can be adjusted according to actual requirements, the minimum size is 5mm, and the maximum length is determined according to the area of a treated water body and the treated water quality, and is not limited herein. The pyrite is low in cost and convenient to obtain, and because the pyrite releases Fe (III) in the oxidation process, fe (III) can promote the electron transfer process, so that the electroactive process of the anode is further promoted, the range of the anode is further enlarged to the area beyond the anode electrode, the repair process of the bottom mud is accelerated, and the degradation effect of organic pollutants in the bottom mud is improved.

On the basis, as shown in fig. 1, the device also comprises a fixed bracket 6 for fixing the three-dimensional cathode system 2, wherein the bottom of the fixed bracket 6 is fixed in the sediment. As a specific scheme, the fixing bracket 6 comprises a plurality of fixing rods 6-1 (4 in fig. 1), and the fixing rods 6-1 comprise a first rod body 6-11 and a second rod body 6-12; the first rod body 6-11 and the second rod body 6-12 are pipe bodies with different pipe diameters, the outer diameter of the second rod body 6-12 is smaller than the inner diameter of the first rod body 6-11, one end of the second rod body 6-12 is inserted into the first rod body 6-11, and the second rod body 6-12 can move along the direction of the first rod body 6-11; one end of the second rod body 6-12, which is far away from the first rod body 6-11, is fixedly connected with the floating body 2-3, and one end of the first rod body 6-11, which is far away from the second rod body 6-12, is fixed in the sediment.

Because the aquatic plants of the invention need to meet specific growing environment, the three-dimensional cathode system 2 needs to always float on the water surface, and the water environment is always in a changing state, the second rod body 6-12 of the fixing bracket 6 of the invention can move up and down along with the movement of the water body, so that the three-dimensional cathode system 2 can rise or fall along with the water level under the action of gravity and buoyancy, and the three-dimensional cathode system is ensured to always float on the surface of the water body. It should be noted that the second rod 6-12 and the first rod 6-11 of the present invention are long enough to ensure that the second rod 6-12 does not separate from the first rod 6-11 when the water surface rises.

As a specific scheme, mounting holes 2-4 corresponding to the number of the fixing rods 6-1 are formed in the floating body 2-3, when the floating body is mounted, the bottom of each fixing rod 6-1 (namely, one end, far away from the second rod body 6-12, of the first rod body 6-11) is inserted into bottom mud for fixation, and the top (namely, one end, far away from the first rod body 6-11, of the second rod body 6-12) is fixedly connected with the floating body 2-3 at the mounting holes 2-4 through screws and the like.

The installation and use method of the device comprises the following steps: firstly, selecting a water body to be treated (the water body comprises bottom mud and a black and odorous water body), paving a layer of pyrite ore as an anode reinforcing material 1-3 at a position 15cm below a mud-water interface from the bottom mud, and placing a three-dimensional anode system 1 above the pyrite ore; then placing a three-dimensional cathode system 2 on the surface of the water body to enable the three-dimensional cathode system to float on the water surface, adding matrix materials into a cathode cavity 2-11 of the three-dimensional cathode system 2, and planting aquatic plants; then, mounting a fixing bracket 6 around the three-dimensional cathode system 2 to fix the three-dimensional cathode system above the three-dimensional anode system 1 so as to prevent the three-dimensional anode system from drifting along with water flow; and finally, connecting the three-dimensional anode system 1 and the three-dimensional cathode system 2 through a lead 3 and a resistor 4 to form a closed loop.

Example 2

A method for synchronously repairing a water body and bottom sediment uses the electrode type artificial ecological floating island device in embodiment 1, a three-dimensional anode system 1 of the device is fixed in the bottom sediment, a three-dimensional cathode system 2 floats on the water surface, and the three-dimensional anode system 1 and the three-dimensional cathode system 2 are connected through a lead 3 and a resistor 4 to form a closed loop. Wherein, as a preferable scheme, the anode reinforcing material 1-3 is embedded in the bottom mud 15cm below the mud-water interface.

The method simultaneously and synchronously purifies and restores the black and odorous water body and the sediment from two aspects:

in a first aspect: the microbial fuel cell is composed of a three-dimensional anode system 1 and a three-dimensional cathode system 2; the anode and the cathode of the microbial fuel cell are respectively arranged in the sediment at the bottom layer of the black and odorous water body and the upper water body, indigenous microbes in the sediment can be attached to the anode electrode, organic matters rich in the sediment are degraded, generated electrons are transmitted to the cathode in the upper water body through an external circuit, the cathode takes oxygen released by photosynthesis of plants in the ecological floating island and secreted by root systems as an electron acceptor, and electrons transmitted by the anode through a lead are received to be reduced, so that a closed loop is formed in the whole system, current is generated, electric energy is generated while bottom mud treatment is realized, weak current can stimulate the growth of microbes to a certain degree, and the water body repairing effect is enhanced.

In a second aspect: an artificial ecological floating island composed of a three-dimensional cathode system 2; firstly, the rhizome of the aquatic plant absorbs or adsorbs nutrient substances such as nitrogen, phosphorus and the like in water, and the matrix material also has certain absorption and adsorption effects, so that the content of pollutants in the water is reduced; secondly, the aquatic plant and the microorganism have a synergistic effect, the root system of the aquatic plant provides a large-area attachment point for the microorganism, and the root of the plant can secrete oxygen, so that an aerobic, anoxic and anaerobic alternate region is formed around the root and stem of the plant, the plant is suitable for the survival of various microorganisms, the degradation of the microorganism on organic pollutants is accelerated, the microorganism can degrade macromolecular substances, and the absorption of the plant on the pollutants can be further promoted; finally, the aquatic plants cover the water surface to reduce photosynthesis of the algae, thereby inhibiting growth of the algae in the water.

Example 3

The electrode type artificial ecological floating island device in the embodiment 1 is placed in a cylinder with the diameter of 50cm, the height of 60cm and the wall thickness of 8cm for simulating water body purification and sediment remediation.

As a specific scheme, a polyethylene plate is adopted for both the anode support plate 1-1 and the cathode support plate 2-1; the anode electrode 1-2 is carbon fiber cloth, and the carbon fiber cloth is attached to the anode support plate 1-1; the cathode electrode 2-2 is a carbon felt which is attached to the cathode support plate 2-1; the conductive metal material 5 is a titanium wire, the titanium wire with the diameter of 1mm penetrates through the carbon fiber cloth in the same anode cavity 1-2 to be connected in series, and then the titanium wires in different anode cavities 1-2 are connected in series according to the S shape through soldering tin; a titanium wire with the diameter of 1.5mm penetrates through the carbon felt in the same cathode cavity 2-2 to be connected in series, and then the titanium wires in different cathode cavities 2-2 are connected in series according to the S shape through soldering tin; the titanium wire of the anode electrode 1-2 and the titanium wire of the cathode electrode 2-2 are connected through a copper wire and are connected in series with a 500 omega resistor to form a closed loop.

In addition, the anode strengthening materials 1-3 are natural pyrite ores with the grain size of 5-12 mm; the floating body is a high-density polyethylene (HDPE) plate with the diameter of 48cm and the thickness of 3cm, and the plate is provided with an opening with the diameter of 3 mm; the matrix material is quartz sand (with the grain diameter of 5-8 mm) and volcanic rock (with the grain diameter of 7-12 mm) which are uniformly mixed, the thickness of the matrix material is 5cm, and aquatic plants are planted above the matrix material.

The aquatic plants are cattail, water spinach and cress, the initial total biomass is set to be 20g/L, the directly purchased aquatic plants are firstly subjected to water planting for a week at 25 ℃, root soil is cleaned, the aquatic plants are transplanted into a matrix material, and the root systems of the aquatic plants penetrate through the open pores of the floating bodies 2-3 and are uniformly distributed.

The water body is purified and the sediment is restored through the device, and the restoration result is shown in fig. 6 and 7. Before restoration, the COD content of the water body in the cylinder is 25.4mg/L, the ammonia nitrogen content is 9.4mg/L, and the total organic carbon content in the bottom mud is 234mg/g; after 60 days of restoration, the COD content in the cylinder is 8.6mg/L, the ammonia nitrogen content is 4.5mg/L, and the total organic carbon content is 104mg/g. Therefore, the device can realize synchronous restoration of the water body and the sediment and has remarkable effect.

The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention will still fall within the protection scope of the technical solution of the present invention.

Claims

1. The electrode type artificial ecological floating island device is characterized by comprising a three-dimensional anode system (1) embedded in bottom mud, a three-dimensional cathode system (2) floating on the water surface, a lead (3) and a resistor (4) which are used for connecting the three-dimensional anode system (1) and the three-dimensional cathode system (2);

the three-dimensional anode system (1) comprises a plurality of anode support plates (1-1), a three-dimensional grid structure is formed among the anode support plates (1-1), each grid forms an anode cavity (1-11), and the anode cavities (1-11) are filled with anode electrodes (1-2);

the three-dimensional cathode system (2) comprises a plurality of cathode supporting plates (2-1), a three-dimensional grid-shaped structure is formed among the cathode supporting plates (2-1), each grid forms a cathode cavity (2-11), and cathode electrodes (2-2) are filled in the cathode cavities (2-11);

the three-dimensional cathode system (2) further comprises a floating body (2-3) which is used for supporting the cathode supporting plates (2-1) and enabling the cathode supporting plates (2-1) to float on the water surface, a space formed by the floating body (2-3) and the cathode cavity (2-11) is filled with a matrix material, and aquatic plants are planted on the matrix material.

2. The electrode-type artificial ecological floating island device according to claim 1, further comprising a conductive metal material (5); after the anode electrodes (1-2) in each anode cavity (1-11) or the cathode electrodes (2-2) in each cathode cavity (2-11) are connected in series through the conductive metal material (5), the anode electrodes (1-2) in different anode cavities (1-11) or the cathode electrodes (2-2) in different cathode cavities (2-11) are connected in series.

3. The electrode-type artificial ecological floating island device according to claim 1, characterized in that the bottom of the anode cavities (1-11) is provided with anode strengthening material (1-3).

4. The electrode-type artificial ecological floating island device according to claim 3, wherein the anode reinforcing material (1-3) is pyrite.

5. The electrode type artificial ecological floating island device according to claim 1, further comprising a fixing bracket (6) for fixing the three-dimensional cathode system (2), wherein the bottom of the fixing bracket (6) is fixed in the bottom sediment.

6. The electrode-type artificial ecological floating island device according to claim 5, wherein the fixed support (6) comprises a plurality of fixed rods (6-1), the fixed rods (6-1) comprise a first rod body (6-11) and a second rod body (6-12); one end of the second rod body (6-12) is inserted into the first rod body (6-11), and the second rod body (6-12) can move along the direction of the first rod body (6-11); one end of the second rod body (6-12) far away from the first rod body (6-11) is fixedly connected with the floating body (2-3), and one end of the first rod body (6-11) far away from the second rod body (6-12) is fixed in the sediment.

7. The electrode type artificial ecological floating island device according to claim 1, wherein the anode electrode (1-2) and the cathode electrode (2-2) are made of carbon material, metal material or conductive polymer material.

8. The electrode type artificial ecological floating island device according to claim 1, wherein the anode support plate (2-1) and the cathode support plate (2-2) are both made of non-conductive insulating materials.

9. Method for simultaneous remediation of a body of water and sediment, characterized in that an electrode-type artificial ecological floating island device according to any one of claims 1-8 is installed in the body of water to be treated.

10. The method for simultaneous remediation of a body of water and sediment as claimed in claim 9, wherein said anode reinforcement material (1-3) is embedded in the sediment 15cm below the interface of the mud and water.