Landscape fish culture ecological circulation purification device and method

Abstract

The invention relates to an ecological circulation purification device for landscape fish culture, a water distribution layer, a coffee residue biochar micro-electrolysis filler layer, a filter layer, an isolation layer and an ecological bed are sequentially arranged in the ecological circulation purification area from bottom to top, outlet water of a fish pond is fed into the water distribution layer, and purified water between the isolation layer and the ecological bed is fed into the fish pond. Filler in the coffee residue biochar micro-electrolysis filler layer is prepared from coffee residue biochar, scrap iron, a binder and an additive through mixing, granulation, drying and high-temperature anaerobic roasting. The coffee residue biochar micro-electrolysis filler has the beneficial effects that by providing the coffee residue biochar micro-electrolysis filler, efficient and stable degradation of pollutants can be realized, the water quality maintenance difficulty during landscape fish culture is reduced, and by utilizing the purification capacity of plants and the regulation effect of the plants on the water microenvironment, the water quality is improved; plant purification and filler purification are combined to form multi-stage ecological purification treatment, and the problems that in landscape fish culture, the treatment effect is not ideal, and the natural ecology is not good are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of water purification treatment, and particularly relates to a landscape fish breeding ecological cycle purification device and method. Background Art

[0002] With the continuous pursuit of a better life by the people, using landscape ponds, glass fish tanks, etc. to breed ornamental fish to create a "natural ecology" environment for living scenes such as communities, offices, and homes has been increasingly favored and recognized by society. However, feed residues and fish excreta will cause the deterioration of the water quality of the breeding water. At the same time, the method of frequently changing water to ensure water quality greatly increases the maintenance cost and difficulty.

[0003] The pollutants in fishpond wastewater include organic matter, ammonia nitrogen, etc. Generally, a packed filter is used for treatment. The electrochemical reaction, catalytic action, and primary battery effect in the micro-electrolysis packing can achieve the efficient removal of various pollutants. The key materials of the micro-electrolysis packing are carbon-based and zero-valent iron. Zero-valent iron generally uses inexpensive iron filings, and the carbon-based material is currently mostly charcoal. Generally, the smaller the size of the carbon-based material, the larger the specific surface area, which can provide more active sites, is easy to form a higher-density primary battery, and helps to improve the reaction efficiency. In addition, the traditional method of simply stacking the carbon-based material and iron filings not only has unstable effects but also easily appears problems such as caking and separation of the anode and cathode. Preparing regular packing can greatly improve the treatment effect and stability.

[0004] About 6 million tons of coffee grounds are generated globally every year. In China, the output of coffee grounds is also increasing year by year. Randomly placing coffee grounds will cause problems such as environmental pollution and resource waste, and the resource utilization of coffee grounds is one of the global research hotspots. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a landscape fish breeding ecological cycle purification device and method to overcome the above deficiencies in the prior art.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] A landscape fish breeding ecological cycle purification device includes: a fishpond and an ecological cycle purification area. From bottom to top in the ecological cycle purification area, there are a water distribution layer, a coffee grounds biochar micro-electrolysis packing layer, a filtration layer, an isolation layer, and an ecological bed. The water discharged from the fishpond is sent into the water distribution layer, and the purified water between the isolation layer and the ecological bed is sent into the fishpond. The packing in the coffee grounds biochar micro-electrolysis packing layer is prepared by mixing coffee grounds biochar, iron filings, a binder, and an additive, granulating, drying, and high-temperature anaerobic roasting.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Further, the mass ratios of coffee ground biochar, iron filings, binder, and additive are (21-40):(32-50):(18-35):(0.5-3.5).

[0010] Further, the coffee ground biochar is prepared by first drying the waste after coffee bean processing and then performing high-temperature treatment at 400°C - 900°C, and its particle size is 50μm - 500μm.

[0011] Further, the iron filings are iron powder processed from the residual waste after iron product processing through a pulverizer, with a particle size of 0 - 2mm and an iron content higher than 97%.

[0012] Further, the binder uses one or a combination of natural bentonite, kaolin, and clay. After natural drying, the binder is sieved through a 100 - 300 mesh sieve; the additive uses one or a combination of ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, and calcium carbonate.

[0013] Further, the processing method of the packing material in the coffee ground biochar micro-electrolysis packing layer is as follows:

[0014] S11. Pour the coffee ground biochar, iron filings, and additive into a mixer in proportion and mix evenly;

[0015] S12. Transfer the mixture to a granulator, and slowly add water during the process to complete granulation. The granule size of the granulation is 5mm - 15mm, and the moisture content of the granules is 10% - 15%;

[0016] S13. Dry the granules at 105°C - 220°C for 15min - 30min;

[0017] S14. Roast the granules under high-temperature anaerobic conditions. The roasting temperature is 500°C - 900°C, and the roasting time is 30min - 60min. Naturally cool to room temperature to obtain the coffee ground biochar micro-electrolysis packing material.

[0018] Further, the water distribution layer includes: a filter material layer and water distribution pipes distributed in the filter material layer. A number of water distribution holes are opened on the water distribution pipes. The water outlet of the fish pond is pumped into the water distribution pipes. The filter material of the filter material layer uses one or a combination of coral stones, shells, and volcanic rocks, with a particle size of 1cm - 3cm, and the thickness of the water distribution layer is 25mm - 40mm; the filter material of the filtering layer uses coral sand with a particle size of 0.5mm - 5mm, and its thickness is 15mm - 40mm; the isolation layer includes: a perforated plate and a permeable geotextile located below the perforated plate.

[0019] Further, the ecological bed includes: a planting bed, on which a number of planting grooves are distributed, and each planting groove is equipped with a perforated flower pot, and aquatic plants are planted in the perforated flower pot.

[0020] Furthermore, the ecological bed is detachably fixed to the pool body in the ecological cycle purification area through bayonets or screws.

[0021] Based on the above technical solution, the present invention also provides a landscape fish farming ecological cycle purification method, which uses the above landscape fish farming ecological cycle purification device and includes the following steps:

[0022] S21. The water to be purified in the fish pond is fed into the water distribution layer and flows upward to the coffee residue biochar microelectrolysis filler layer. The coffee residue biochar and zero-valent iron in the filler form a primary battery, and a large number of electrons and highly reactive substances are generated through electrochemical reactions, accompanied by coagulation adsorption, catalytic oxidation, complexation, and electrodeposition to degrade organic matter and nitrogen and phosphorus pollutants in the water.

[0023] S22. The water flowing out of the coffee residue biochar microelectrolysis filler layer flows upward through the filter layer and the isolation layer in sequence and enters the space between the isolation layer and the ecological bed. The plant roots further absorb the excess nutrients in the water to purify the water quality and improve and maintain the water transparency.

[0024] S23. The purified water between the isolation layer and the ecological bed flows into the fish pond by gravity to achieve circulation.

[0025] The beneficial effects of the present invention are as follows:

[0026] Using coffee residue biochar as the carbon-based raw material, it has small particle size and large specific surface area, and is easy to form a primary battery with zero-valent iron, which can provide more adsorption sites and improve its adsorption performance. It has rich microporous and mesoporous structures and is easy for microorganisms to attach membranes. Further, regular granular microelectrolysis fillers are prepared from materials such as iron filings, binders, and additives. The microelectrolysis fillers can achieve efficient and stable degradation of pollutants, reduce the difficulty of water quality maintenance during landscape fish farming, and utilize the purification ability of plants and their regulation of the water microenvironment. The combination of plant purification and filler purification constitutes a multi-level ecological purification treatment, which conforms to the direction of green and low-carbon development. The microelectrolysis fillers can efficiently remove the main pollutants, while the plant roots further absorb the excess nutrients in the water to purify the water quality. At the same time, the plant roots will improve and maintain the water transparency, improve the ornamental value of landscape fish farming and the survival rate of fish, maintain the healthy growth of fish, reduce the risk of excessive plant growth, achieve the natural ecological effect, increase the "natural ecological effect", and provide an efficient and natural method for landscape fish farming in general families, office buildings, parks, villas, etc. At the same time, it realizes the resource utilization of coffee residues and innovatively provides the application of coffee residues in the field of landscape fish farming. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram of the landscape fish farming ecological cycle purification device;

[0028] Figure 2 It is a structural diagram of an ecological bed.

[0029] In the attached drawings, the list of components represented by each label is as follows:

[0030] 1. Fish pond, 2. Ecological circulation purification area, 210. Water distribution layer, 220. Coffee grounds biochar microelectrolysis filler layer, 230. Filter layer, 240. Isolation layer, 250. Ecological bed, 251. Planting bed, 252. Hollow flower pot, 253. Aquatic plants. Specific implementation manners

[0031] The principles and features of the present invention will be described below in conjunction with the attached drawings. The examples cited are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0032] Example 1

[0033] As Figure 1 shown, a landscape fish farming ecological circulation purification device includes: a fish pond 1 and an ecological circulation purification area 2. The ecological circulation purification area 2 can be designed as an integrated device with the fish pond 1 or can be independently designed. There is no clear limitation here, and the specific selection is determined according to actual needs;

[0034] Inside the ecological circulation purification area 2, from bottom to top, there are a water distribution layer 210, a coffee grounds biochar microelectrolysis filler layer 220, a filter layer 230, an isolation layer 240, and an ecological bed 250 in sequence;

[0035] The water discharged from the fish pond 1 is sent into the water distribution layer 210, and the purified water between the isolation layer 240 and the ecological bed 250 is sent into the fish pond 1. That is, the ecological circulation purification area 2 adopts the method of lower water inlet and upper water outlet. The filler in the coffee grounds biochar microelectrolysis filler layer 220 is prepared by mixing, granulating, drying, and high-temperature anaerobic roasting of coffee grounds biochar, iron filings, binders, and additives;

[0036] The coffee grounds biochar in the coffee grounds biochar microelectrolysis filler layer 220 and zero-valent iron form a primary battery, generating a large number of electrons and highly reactive substances through electrochemical reactions, and accompanied by coagulation adsorption, catalytic oxidation, complexation, electrodeposition and other effects to achieve the effect of degrading organic matter and nitrogen and phosphorus pollutants in water. Using coffee grounds biochar, iron filings, binders, and additives as fillers, it has a porous structure, and the coffee grounds biochar has a high specific surface area, which is easy to form a primary battery with zero-valent iron, thereby providing more adsorption sites and improving its adsorption performance. It has a rich microporous and mesoporous structure, which is easy for microorganisms to attach membranes, and then adsorb and purify pollutants in water;

[0037] The effluent in the coffee residue biochar microelectrolysis packing layer 220 flows through the filter layer 230 and the isolation layer 240 in sequence from bottom to top, and enters the space between the isolation layer 240 and the ecological bed 250. The filter layer 230 is mainly used to further ensure the effluent water quality. On the one hand, the isolation layer 240 prevents the small particle materials in the filter layer 230 from being washed away and lost. On the other hand, it can block the plant roots in the ecological bed 250 from entering the underlying packing. The water that enters the space between the isolation layer 240 and the ecological bed 250 is further absorbed by the plant roots to remove the excess nutrients in the water to purify the water quality, and to improve and maintain the water transparency. By combining the purification ability of plants and their regulation of the water microenvironment, the plant purification and packing purification are combined to form a multi-stage ecological treatment, so as to solve the problems of unsatisfactory treatment effect and poor "natural ecology" in the landscape fish farming.

[0038] Example 2

[0039] This example is a further optimization based on Example 1, and the details are as follows:

[0040] The mass ratio of coffee residue biochar, iron filings, binder, and additive is (21 - 40):(32 - 50):(18 - 35):(0.5 - 3.5).

[0041] Example 3

[0042] This example is a further optimization based on Example 1 or 2, and the details are as follows:

[0043] The coffee residue biochar is prepared by first drying the waste after coffee bean processing and then performing high-temperature treatment at 400°C - 900°C, and its particle size is 50μm - 500μm.

[0044] The iron filings are iron powder processed from the residual waste after iron product processing through a pulverizer, with a particle size of 0 - 2mm and an iron content higher than 97%.

[0045] The binder uses a combination of one or more of natural bentonite, kaolin, and clay, and the binder is sieved through a 100 - 300 mesh sieve after natural drying.

[0046] The additive uses a combination of one or more of ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, and calcium carbonate.

[0047] Example 4

[0048] This example is a further optimization based on Example 1 or 2 or 3, and the details are as follows:

[0049] The processing method of the packing in the coffee residue biochar microelectrolysis packing layer 220 is as follows:

[0050] S11. Pour coffee ground biochar, iron filings, and additives into a mixer in proportion and mix evenly.

[0051] S12. Transfer the mixture to a granulator and slowly add water during the process to complete granulation. The granule size is 5 mm to 15 mm, and the moisture content of the granules is 10% to 15%.

[0052] S13. Dry the granules at 105°C to 220°C for 15 min to 30 min.

[0053] S14. Roast the granules under high-temperature and oxygen-free conditions. The roasting temperature is 500°C to 900°C, and the roasting time is 30 min to 60 min. Let it cool naturally to room temperature to obtain the coffee ground biochar microelectrolysis filler. During the high-temperature roasting process, the additives can decompose into gaseous substances and escape at high temperature to increase the specific surface area of the filler.

[0054] Example 5

[0055] As Figure 1 shown, this example is a further optimization based on any one of Examples 1 to 4, and the specific details are as follows:

[0056] The water distribution layer 210 includes: a filter material layer and water distribution pipes distributed in the filter material layer. A number of water distribution holes are opened on the water distribution pipes. The effluent of the fish pond 1 is pumped into the water distribution pipes. The filter material of the filter material layer is a combination of one or more of coral stone, shell, and volcanic rock, and its particle size is 1 cm to 3 cm. The above filter materials are all natural materials, with wide sources, low prices, stable chemical properties, good physical structure strength, and a porous structure. While achieving uniform water distribution, it is conducive to the attachment and growth of microorganisms and helps with water quality purification. In this example, the thickness of the water distribution layer 210 is preferably 25 mm to 40 mm.

[0057] The filter material of the filtration layer 230 is coral sand with a particle size of 0.5 mm to 5 mm. Coral sand has a microporous structure, good microbial adsorption capacity and pollutant interception capacity, further ensuring the effluent water quality. In this example, the thickness of the filtration layer 230 is preferably 15 mm to 40 mm.

[0058] The isolation layer 240 includes: a perforated plate and a permeable geotextile located below the perforated plate. The perforated plate is made of a high-strength and lightweight polymer plastic, with water permeable holes opened on it. It is connected and fixed to the pool body of the ecological circulation purification area 2 to prevent the filler below from shifting due to water flow scouring. The permeable geotextile has good water permeability and tensile strength, stable chemical properties, and a long service life. On the one hand, it prevents the small particle materials in the filtration layer from being washed away and lost, and on the other hand, it can block the plant roots from entering the filler below.

[0059] Example 6

[0060] As Figure 2 shown, this embodiment is a further optimization based on any one of Embodiments 1 to 5, and is specifically as follows:

[0061] The ecological bed 250 includes: a planting bed 251, which is made of polymer materials such as polyester fiber and polyethylene, is light in weight and durable. A number of planting grooves are distributed on the planting bed 251, and a hollow flower pot 252 is arranged in each planting groove. Aquatic plants 253 are planted in the hollow flower pot 252, and the hollow flower pot 252 can prevent the roots from growing disorderly.

[0062] The ecological bed 250 is preferably fixed to the pool body of the ecological circulation purification area 2 in a detachable manner through bayonets or screws. According to the growth situation of the plants, the ecological bed 250 can be regularly removed to conveniently clean the plant stems, leaves and their roots, avoid secondary pollution caused by plant aging, and reduce the risk of blockage caused by excessive growth of plant roots.

[0063] Embodiment 7

[0064] A method for ecological circulation purification of landscape fish culture, using the above-mentioned ecological circulation purification device for landscape fish culture, includes the following steps:

[0065] S21. The water to be purified in the fish pond 1 is sent into the water distribution layer 210 and flows upward to the coffee residue biochar microelectrolysis filler layer 220. The coffee residue biochar in the filler and the zero-valent iron form a primary battery, and a large number of electrons and highly reactive substances are generated through electrochemical reactions, accompanied by coagulation adsorption, catalytic oxidation, complexation, and electrodeposition to degrade organic matter and nitrogen and phosphorus pollutants in the water;

[0066] S22. The water outlet in the coffee residue biochar microelectrolysis filler layer 220 flows upward through the filter layer 230 and the isolation layer 240 in sequence, and enters between the isolation layer 240 and the ecological bed 250. The plant roots further absorb the excess nutrients in the water to purify the water quality and improve and maintain the water transparency;

[0067] S23. The purified water between the isolation layer 240 and the ecological bed 250 flows into the fish pond 1 in a self-flowing manner to achieve circulation.

[0068] Experimental Example 1

[0069] The test device is an acrylic tank with a length, height and width of 80 cm × 50 cm × 50 cm. A partition is designed in the middle to divide the inner cavity of the acrylic tank into an independent fish pond and an ecological circulation purification area. An overflow hole is arranged at a position 10 cm away from the top of the partition. The size of the fish pond is 60 cm × 50 cm × 50 cm, and the test fish are 10 grass goldfish with a length of 5 cm to 7 cm.

[0070] The ecological bed is 60 cm in length and 50 cm in width, designed to plant 8 water cresses. The initial height of the water cress seedlings is about 8 cm - 10 cm, without leaves but with root hairs.

[0071] The filter material of the water distribution layer 210 is coral stone. The thickness of the water distribution layer 210 is 30 mm. A water distribution pipe with a length of 40 cm and a diameter of 15 mm is longitudinally arranged in the water distribution layer 210.

[0072] The thickness of the coffee residue biochar micro - electrolysis filler layer 220 is 35 cm. The processing method of the filler in the coffee residue biochar micro - electrolysis filler layer 220 is as follows:

[0073] 1) Purchase coffee residue, which is the waste from domestic coffee bean processing. First, it is naturally dried and then activated at 600 °C at high temperature to obtain coffee residue biochar;

[0074] 2) Collect iron product processing waste particles and further process them in a crusher into iron powder with a size less than 1 mm;

[0075] 3) Use 200 - mesh bentonite as the binder and calcium carbonate powder as the additive. The mass ratio of coffee residue biochar: iron filings: bentonite: calcium carbonate is 24:48:27.5:1.5, and use a mixer to mix them evenly;

[0076] 4) Transfer the mixture into a granulator, slowly spray water, and rotate to granulate. The granulation size is 5 mm - 7 mm, and the moisture content of the particles is tested to be 13%;

[0077] 5) Dry the granulated particles at 105 °C for 30 min;

[0078] 6) Roast the particles under high - temperature anaerobic conditions at 550 °C for 30 min. After roasting, naturally cool to room temperature to obtain the coffee residue biochar micro - electrolysis filler.

[0079] The filter material of the filtration layer 230 is coral sand with a particle size of 0.5 mm - 5 mm, and the thickness is 20 mm.

[0080] The hollow plate in the isolation layer 240 is processed with thick organic glass plate and is provided with permeable holes. The lower part is polyester permeable geotextile.

[0081] First, assemble the whole device completely and soak it in water for 1 day, then change the water, repeat 3 times to remove the scum, and then continue to soak for 2 weeks to ensure that the filler can be normally film - forming in the later stage;

[0082] Then the experiment began. During the experiment, fish feed was fed in the morning and afternoon every day. An air pump was used to supply oxygen to the fish pond, and a submersible pump was used for pumping water circulation, about 12 times a day. The water quality was regularly tested during the experiment, and the growth of fish and plants was observed. To make up for the water loss caused by evaporation, a small amount of water was supplemented to keep the water level constant. Due to the limitation of the plant growth cycle, the experimental time was set to 90 days. After the experiment, the surviving fish were taken to test the content of serum enzymes, and the floating beds were taken down to analyze the plant growth weight and root system conditions.

[0083] Experimental group 2

[0084] The device is basically the same as that of experimental group 1, but the micro-electrolysis filler in the coffee residue biochar micro-electrolysis filler layer 220 is replaced with commercially available ceramsite, and the size of the ceramsite is 5mm - 10mm.

[0085] Experimental group 3:

[0086] The device is basically the same as that of experimental group 1, but there is no ecological bed.

[0087] Experimental group 4

[0088] The device is basically the same as that of experimental group 1, but the additive is ammonium oxalate, and the mass ratio of coffee residue biochar: iron filings: bentonite: ammonium oxalate is 30:40:29:1.

[0089] Table 1 Operation conditions of each experimental group

[0090]

[0091]

[0092] According to the experimental operation data, it can be seen that the water quality indexes COD, ammonia nitrogen, chlorophyll a, and turbidity in the fish pond using the ecological cycle purification method of the present invention are all lower than those of the control group (Experimental Examples 2 and 3), indicating that the coffee residue micro-electrolysis filler has a higher removal effect on organic matter and nitrogen and phosphorus pollutants than general fillers. After being combined with plant purification, the turbidity can be further reduced. At the same time, compared with the control group, the plant weight in the experimental group increases more slowly, and the plant roots are normal. This is because the coffee residue micro-electrolysis filler has a good removal effect on nitrogen and phosphorus in water, will not cause the plants to grow wildly, and reduces the risk of secondary pollution caused by plant aging. Compared with the control group, the survival rate of fish in the experimental group is higher, and the serum protein content in the fish body is lower. Normally, the serum protein content in the fish body is not high, but when the fish's internal liver is damaged and the metabolism is abnormal due to the poor water environment, the serum protein content will increase. This shows that the ecological cycle purification method of the present invention not only reduces the physical and chemical indexes of the fish pond water quality, but also has an effect on maintaining the healthy growth of fish.

[0093] In summary, the ecological cycle purification method provided by the present invention, which combines coffee residue microelectrolysis fillers with plant purification, can not only purify pollutants in water, but also maintain the light and transparent feeling of water quality, maintain the healthy growth of fish, reduce the risk of excessive plant growth, and achieve the effect of natural ecology. The technology of the present invention effectively solves the problems of insufficient water treatment effect and poor sensory experience in the process of general landscape fish farming, and also innovatively realizes the application of coffee residue in the field of landscape fish farming.

[0094] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A landscape fish farming ecological cycle purification device, characterized in that: include: A fish pond (1) and an ecological circulation purification area (2), wherein the ecological circulation purification area (2) comprises, from bottom to top, a water distribution layer (210), a coffee grounds biochar micro-electrolysis filler layer (220), a filter layer (230), an isolation layer (240) and an ecological bed (250), the effluent of the fish pond (1) is sent into the water distribution layer (210), the purified water between the isolation layer (240) and the ecological bed (250) is sent into the fish pond (1), and the filler in the coffee grounds biochar micro-electrolysis filler layer (220) is prepared by mixing coffee grounds biochar, iron filings, a binder and an additive, granulating, drying and high-temperature anaerobic roasting.

2. The landscape fish farming ecological cycle purification device according to claim 1 is characterized in that: The mass ratio of the coffee grounds biochar, iron filings, binder and additive is (21-40): (32-50): (18-35): (0.5-3.5).

3. A landscape fish breeding ecological cycle purification device according to claim 1 or 2, characterized in that: The coffee grounds biochar is prepared by first drying the waste after coffee bean processing and then subjecting it to a high-temperature treatment at 400° C. to 900° C., and its particle size is 50 μm to 500 μm.

4. A landscape fish breeding ecological cycle purification device according to claim 1 or 2, characterized in that: The iron filings are iron powders made by processing residual waste after iron product processing through a crusher, with a particle size of 0 to 2 mm and an iron content of more than 97%.

5. A landscape fish breeding ecological cycle purification device according to claim 1 or 2, characterized in that: The binder is a combination of one or more of natural bentonite, kaolin and clay, and the binder is naturally dried and then sieved through a 100-300 mesh sieve; the additive is a combination of one or more of ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate and calcium carbonate.

6. A landscape fish farming ecological cycle purification device according to any one of claims 1 to 5, characterized in that: The method for processing the filler in the coffee grounds biochar micro-electrolysis filler layer (220) is as follows: S11, pouring coffee grounds biochar, iron filings, and additives into a mixer according to proportions and mixing them evenly; S12, transferring the mixture into a granulator, slowly adding water during the process, completing granulation, the granulated particles have a size of 5 mm to 15 mm, and the moisture content of the particles is 10% to 15%; S13, drying the particles at 105°C to 220°C for 15min to 30min; S14. Roast the particles under high temperature and anaerobic conditions at a temperature of 500°C to 900°C for 30 min to 60 min, and naturally cool to room temperature to obtain coffee grounds biochar micro-electrolysis filler.

7. A landscape fish farming ecological cycle purification device according to any one of claims 1 to 5, characterized in that: The water distribution layer (210) comprises: a filter material layer and a water distribution pipe distributed in the filter material layer, the water distribution pipe is provided with a plurality of water distribution holes, and the water discharged from the fish pond (1) is pumped into the water distribution pipe, the filter material of the filter material layer is a combination of one or more of coral stone, shell, and volcanic rock, and its particle size is 1 cm to 3 cm, and the thickness of the water distribution layer (210) is 25 mm to 40 mm; the filter material of the filter layer (230) is coral sand with a particle size of 0.5 mm to 5 mm, and its thickness is 15 mm to 40 mm; the isolation layer (240) comprises: a hollow plate and a permeable geotextile located below the hollow plate.

8. The landscape fish farming ecological cycle purification device according to any one of claims 1 to 5, characterized in that: The ecological bed (250) comprises: a planting bed (251), wherein a plurality of planting grooves are distributed on the planting bed (251), each planting groove is provided with a hollow flower pot (252), and aquatic plants (253) are planted in the hollow flower pot (252).

9. The landscape fish farming ecological cycle purification device according to any one of claims 1 to 5, characterized in that: The ecological bed (250) is detachably fixed to the pool body of the ecological cycle purification area (2) by means of a bayonet or a screw.

10. A landscape fish farming ecological cycle purification method, characterized in that: The landscape fish farming ecological cycle purification device according to any one of claims 1 to 9 comprises the following steps: S21, the effluent to be purified in the fish pond (1) is sent to the water distribution layer (210), and flows from bottom to top to the coffee grounds biochar micro-electrolysis filler layer (220), the coffee grounds biochar in the filler and the zero-valent iron form a primary cell, and a large amount of electrons and highly reactive substances are generated through electrochemical reactions, accompanied by coagulation adsorption, catalytic oxidation, complexation, and electrodeposition, so as to degrade organic matter and nitrogen and phosphorus pollutants in the water; S22, the water from the coffee grounds biochar micro-electrolysis filler layer (220) flows through the filter layer (230) and the isolation layer (240) in sequence from bottom to top, and enters between the isolation layer (240) and the ecological bed (250), and the plant roots further absorb excess nutrients in the water to purify the water quality, and Improve and maintain water clarity; S23, the purified water between the isolation layer (240) and the ecological bed (250) flows into the fish pond (1) by gravity to achieve circulation.

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