CN116768371A - Ecological system of aquaculture tail water and operation method - Google Patents

Abstract

The invention provides an ecological system and an operation method of aquaculture tail water, wherein the ecological system comprises an ecological ditch and a horizontal subsurface flow constructed wetland, and the ecological ditch is transformed by the ditch of a cultivation area; the horizontal subsurface flow constructed wetland is transformed by a pond or a peripheral river channel of a cultivation area and comprises a water inlet channel, a book outlet channel and a wetland, wherein the water inlet channel and the water outlet channel are relatively arranged on two sides of the wetland, the water inlet channel is connected with the ecological channel through a drainage pipeline, the water outlet channel is provided with a water pump, the wetland comprises a plurality of wetland units connected in parallel, emergent aquatic plants and/or floating plants are planted on the wetland units, and a mud discharging mechanism is further arranged at the bottom of the wetland units. The ecological system of the aquaculture tail water has the advantages of small occupied area, low operation cost and investment cost, recycling of the tail water, effective utilization of resources, ecological environment friendliness, no secondary pollution to the environment, good treatment effect of the aquaculture tail water and stable water quality reaching the standard.

Description

Ecological system of aquaculture tail water and operation method

Technical Field

The invention relates to the technical field of ecological restoration of water, in particular to an ecological system of aquaculture tail water. The invention also relates to an operation method of the ecological system of the aquaculture tail water

Background

Pond culture is a main mode of freshwater aquaculture in China, along with the implementation of planning and promulgation of the aquaculture water surface, a large number of traditional aquaculture water surfaces such as lakes, reservoirs and the like are divided into forbidden areas, and in addition, the pressure such as industrial pollution, agricultural non-point source pollution and the like is added, so that the nationwide aquaculture area is greatly reduced, and many problems such as ageing of pond culture facilities, low benefit and difficult tail water treatment are solved, so that the purposes of high yield, high efficiency and greenness are achieved through the traditional pond culture mode, and the difficulty is increased.

At present, the treatment modes of the pond culture tail water are generally a physical method, a chemical method and three ponds and two dams, and the specific conditions are as follows:

1) Physical method

The physical method comprises a mechanical filtering technology, a physical water hanging technology and a foam separation technology.

The mechanical filtering technology mainly relies on the mechanical power of the filtering equipment and a screen structure to effectively filter and remove pollutants and impurities in the water body, so that the effect of improving the tail water environment is achieved. In specific practice, since most of the water bodies in the cultivation environment contain some tiny particulate organic matters, the filtration is difficult to be performed by the common filtration equipment. Based on this, the skilled person needs to develop some high-end devices with a small aperture. Therefore, mechanical filtration technology itself requires relatively high equipment performance and specifications, and the cost input ratio is also large, so that it is not suitable for decentralized and large-scale aquaculture work.

In the physical water hanging technology, in general, when the pollution degree of organic matters in the water body exceeds the standard, technicians can adopt the technology to scientifically intervene on the quality of the water body, such as mechanical oxygenation, water adding and the like. The operation of adding water is simple, the cost is low, and the effective cleaning and dilution of pollutants can be realized. The mechanical oxygenation can influence the current oxygen consumption situation of organic matters in the water body, so that the aquaculture of fishes and shrimps can obtain basic breathing conditions, and the decomposition speed of fecal secretion and residual baits in the water body is improved. However, the method cannot completely solve the current water pollution problem, and has certain condition.

In the foam separation technology, foam can move to a certain extent in a water body, nearby impurities are adsorbed on the surface, foam is manufactured at the middle lower part of the water body, a large amount of impurities or organic matters are adsorbed in the foam, and then the foam floats out to remove the impurities and the organic matters so as to achieve a good treatment effect. In practice, the foam separation technology is more suitable for the tail water treatment of mariculture, and the effect of the fresh water body treatment is not obvious enough.

2) Chemical process

The chemical method for the cultivation wastewater treatment is usually chemical oxidation, common oxidants include ozone, hydrogen peroxide, chlorine dioxide, liquid chlorine and the like, and the oxidants have the effect of oxidizing and decomposing the dissolved organic matters which are difficult to biodegrade, so that the method is a main means for the cultivation wastewater advanced treatment. The principle of the ozone is that intermediate substances decomposed in water are subjected to radical free radicals of 1-0H) to decompose dissolved organic matters which are difficult to oxidize by common oxidants, and the research shows that 99.9% of various bacteria in seawater can be eliminated by ozone. The ozone is used for treating the wastewater, so that the dissolved oxygen in the water can be increased, the oxygen content of the culture water body can be increased, and toxic and harmful components such as bacteria, viruses and ammonia can be rapidly eliminated, thereby achieving the purposes of purifying the culture wastewater and improving the culture water body. In general, chemical oxidation has advantages of high treatment efficiency, but requires specific equipment and equipment, is expensive, and is easy to cause secondary pollution due to excessive reagent, and currently, ozone oxidation technology has been widely used for treatment of circulating water for mariculture in japan of the united states, europe and asia.

3) Three-pool two-dam

The main flow of the mode is ecological ditch-sedimentation tank-filtering dam-aeration tank-filtering dam-ecological purifying tank. The mode carries out scientific planning on the cultivation water area, and on the basis of pond upgrading and reconstruction (water inlet and drainage are separated), ecological treatment is carried out on cultivation tail water by using a physical and biological ecological method, so that recycling or standard emission is realized. The mode tail water treatment area is required to occupy 5% -10% of the total area, and the method is suitable for a concentrated fresh water continuous pond. The method has large occupied area and limited applicable conditions.

In general, the existing treatment mode of the pond culture tail water has the problems of high equipment cost, high cost, poor treatment effect, possibility of secondary pollution and the like, and has limitations on treatment occasions or environments and the like.

Disclosure of Invention

The invention aims to provide an ecological system of aquaculture tail water, which overcomes the defects in the prior art.

In order to solve the technical problems, the technical scheme of the invention is as follows: an ecological system of aquaculture tail water comprises an ecological ditch and a horizontal subsurface flow constructed wetland, wherein the ecological ditch is transformed by the ditch of a cultivation area; the horizontal subsurface flow constructed wetland is reformed by a pond or a peripheral river channel of a cultivation area and comprises a water inlet channel, a book outlet channel and a wetland, wherein the water inlet channel and the water outlet channel are oppositely arranged at two sides of the wetland, the water inlet channel is connected with the ecological channel through a drainage pipeline, the water outlet channel is provided with a water pump, and the wetland comprises a plurality of wetland units connected in parallel; the wetland unit comprises a wetland packing layer and plants planted above the wetland packing layer, wherein the plants are emergent aquatic plants and/or floating plants, and a mud discharging mechanism is further arranged at the bottom of the wetland unit. The wetland unit mainly plays a role in removing pollutants, the water inlet channel mainly plays a role in collecting aquaculture tail water, and the water outlet channel mainly plays a role in collecting treated aquaculture tail water; the water pump discharges the tail water treated in the water outlet channel into the river channel or the culture pond.

Further, the ecological system of the aquaculture tail water, the ecological ditch comprises an ecological packing layer and emergent aquatic plants planted on the ecological packing layer, the ecological packing layer comprises a planting soil layer I and a gravel layer which are sequentially arranged from top to bottom, and the bottom and the periphery of the ecological ditch are provided with an impermeable layer I.

Further, in the above ecological system for aquaculture tail water, the slope of the wetland unit is 0.5% -1%, and the aspect ratio is 2:1, a step of; the surface hydraulic load of the wetland unit is 0.3-1m < 3 >/(m < 2 >. D).

Further, in the ecological system of the aquaculture tail water, the wetland packing layer comprises a planting soil layer II, an upper gravel layer and a main packing layer which are sequentially arranged from top to bottom, wherein the two sides of the main packing layer are provided with side gravel layers, the side gravel layers are in right-angle triangle shapes, and the slope ratio of the inner inclined surfaces is 1/3-1/2.

Further, in the ecological system of the aquaculture tail water, the gravel grain size of the side gravel layer is larger than that of the upper gravel layer, the gravel grain size of the upper gravel layer is 5-10mm, and the gravel grain size of the side gravel layer is 80-120mm.

Furthermore, in the ecological system of the aquaculture tail water, the main packing layer is a packing layer mixed by zeolite, volcanic rock and embedded microorganism packing, the mixing ratio of the zeolite, the volcanic rock and the embedded microorganism packing is 1:2:1, and the mixing grain size is 10-80 mm.

Furthermore, in the ecological system of the aquaculture tail water, the periphery of the wetland unit is a brick wall body, the height of the wall body is 1.5-2m, and the height of the wall body is 0.2-0.3m higher than the ground; and the periphery and the bottom of the wall body of the wetland unit are provided with a second impermeable layer, and the wetland filler layer is arranged in the impermeable layer.

Furthermore, in the ecological system of the aquaculture tail water, one side of the bottom of the wetland unit is provided with a water distribution pipeline communicated with the water inlet channel, the other side of the bottom of the wetland unit is provided with a water collecting pipeline communicated with the water outlet channel, and the water distribution pipeline and the water outlet pipeline are oppositely arranged below the side gravel layer; the water distribution pipeline and the water outlet pipeline are uniformly distributed, and the distance between the pipelines is 30-60cm; a plurality of water passing holes which are uniformly distributed are formed in the water distribution pipeline and the water outlet pipeline; and the water distribution pipeline of each wetland unit is provided with an independent water inlet valve, and the water collection pipeline of each wetland unit is provided with an independent water outlet valve.

Further, the ecological system of aquaculture tail water, the mud discharging mechanism comprises a membrane pouring pipe and a mud discharging valve, wherein the membrane pouring pipe is arranged at the bottom of each wetland unit and is positioned below the water collecting pipeline, and the membrane pouring pipe of each wetland unit is provided with an independent mud discharging valve.

The invention also provides an operation method of the ecological system of the aquaculture tail water, which comprises the following steps:

s1, when the system starts to operate, water in the ecological ditch is discharged into the horizontal subsurface flow constructed wetland, so that the water level of the wetland rises to a position 10cm below the wetland packing layer, and after the system is stabilized, water is continuously fed to rise to the surface of the wetland packing layer;

s2, when the system operates normally, a water inlet valve and a water outlet valve are opened, a mud outlet valve is closed, the horizontal subsurface flow constructed wetland automatically treats the culture tail water, and the treated tail water is discharged into a river channel or a culture pond;

s3, the horizontal subsurface flow constructed wetland adopts an intermittent operation mode, and a plurality of wetland units work intermittently in turn, so that the long-acting operation of the wetland is ensured;

s4, starting a sludge discharge mechanism to discharge sludge after one end of normal operation, opening a water inlet valve and a sludge outlet valve, closing the water outlet valve, and discharging the sludge of the wetland unit out of the wetland through hydraulic flushing;

s5, in winter, the wetland is kept at a high water level from the ecological canal or an external river, so that the survival rate of plants and the temperature of the wetland are ensured;

s6, harvesting plants in the ecological canal and the horizontal subsurface flow constructed wetland in time during season replacement, and reseeding when the plant growth density is insufficient.

Compared with the prior art, the invention has the beneficial effects that:

(1) The ecological ditch plays a role in preliminarily filtering and adsorbing pollutants; the wetland unit mainly plays a role in removing pollutants, emergent aquatic plants and floating plants are planted in the wetland, plays a role in absorbing nutrient substances, heavy metals and the like, and enhances ecological landscape; aquatic animals are also cultivated, so that the biodiversity is realized, and meanwhile, nutrient substances can be absorbed; the horizontal subsurface flow constructed wetland mainly has the functions of removing SS, removing N, removing P, removing COD, removing BOD, removing heavy metals and harmful substances, and the like, and simultaneously has the functions of improving landscapes and building an ecological system.

(2) The ecological canal and the horizontal subsurface flow constructed wetland are subjected to on-site environmental transformation, so that the occupied ponds are small, the occupied area is small, and the operation cost can be reduced. The plurality of wetland units connected in parallel can realize intermittent operation of a single wetland unit, so that long-acting operation of the wetland is ensured, and meanwhile, the pollutant removal effect is better; the sludge discharge mechanism can discharge the bottom sludge of the wetland into the wetland, so that the occurrence of clogging of the wetland is prevented. Therefore, the ecological system of the aquaculture tail water has small occupied area, low operation cost and investment cost, can realize effective utilization of resources, is ecological and environment-friendly, does not produce secondary pollution to the environment, has good treatment effect on the aquaculture tail water, and ensures that the water quality is stable and reaches the standard.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings may be obtained according to the drawings without inventive effort to those skilled in the art.

FIG. 1 is a schematic diagram of the ecological system of the aquaculture tail water of the present invention;

FIG. 2 is a schematic view of an ecological ditch of the ecological system of the aquaculture tail water according to the present invention;

FIG. 3 is a schematic diagram of the structure of a horizontal subsurface flow constructed wetland of the ecosystem of the aquaculture tail water of the present invention;

FIG. 4 is a schematic diagram of the distribution of water distribution pipes and technical pipes of the ecological system of the aquaculture tail water of the present invention;

FIG. 5 is a schematic distribution diagram of a membrane pouring tube of the ecological system of the aquaculture tail water according to the present invention;

in the figure: 1. an ecological ditch; 11. planting a soil layer I; 12. a gravel layer; 13. an impermeable layer I;

2. horizontal subsurface flow constructed wetland; 21. a water inlet channel; 22. discharging a book channel; 23. a wetland unit; 231. planting a soil layer II; 232. applying a gravel layer; 233. a main filler layer; 234. a side gravel layer; 235. an impermeable layer II; 24. a mud discharging mechanism; 241. a film pouring tube; 242. a mud outlet valve; 25. a water distribution pipeline; 26. a water collecting pipe; 27. a water inlet valve; 28. a water outlet valve; 29. a water pump;

3. and a drainage pipeline.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

1-3, the ecological system of the aquaculture tail water comprises an ecological ditch 1 and a horizontal subsurface flow constructed wetland 2, wherein the ecological ditch 1 is modified by a ditch of a cultivation area, is reasonably utilized, and reduces the occupied area; the horizontal subsurface flow constructed wetland 2 is reformed by a pond or a peripheral river channel of a cultivation area and comprises a water inlet canal 21, a book outlet canal 22 and a wetland, wherein the water inlet canal 21 and the water outlet canal 22 are oppositely arranged on two sides of the wetland, the water inlet canal 21 is connected with the ecological canal 1 through a drainage pipeline 3, the water outlet canal 22 is provided with a water pump 29, and the wetland comprises a plurality of wetland units 23 which are connected in parallel; the wetland unit 23 comprises a wetland filler layer and plants planted above the wetland filler layer, wherein the plants are emergent aquatic plants and/or floating plants, and a mud discharging mechanism 24 is further arranged at the bottom of the wetland unit 23. The water inlet canal 21 mainly plays a role in collecting aquaculture tail water, and the water outlet canal 22 mainly plays a role in collecting treated aquaculture tail water; the water pump 29 discharges the treated tail water in the water outlet channel 22 into a river or a culture pond, and the treated culture tail water can be reused for aquaculture.

The ecological ditch 1 plays a role in preliminarily filtering and adsorbing pollutants; the wetland unit 23 mainly plays a role in removing pollutants, emergent aquatic plants and floating plants are planted in the wetland, plays a role in absorbing nutrient substances, heavy metals and the like, and enhances ecological landscape; aquatic animals are also cultivated, so that the biodiversity is realized, and meanwhile, nutrient substances can be absorbed; the horizontal subsurface flow constructed wetland 2 mainly has the functions of removing SS, removing N, removing P, removing COD, removing BOD, removing heavy metals and harmful substances, and the like, and simultaneously has the functions of improving landscapes and building an ecological system.

The ecological ditch 1 and the horizontal subsurface flow constructed wetland 2 occupy less ponds and small occupied areas through on-site environmental transformation, and can reduce operation cost. The plurality of wetland units 23 connected in parallel can realize intermittent operation of a single wetland unit, so that long-acting operation of the wetland is ensured, and meanwhile, the pollutant removal effect is better; the sludge discharging mechanism 24 can discharge the bottom sludge of the wetland out of the wetland, so that the wetland is prevented from being blocked. Therefore, the ecological system of the aquaculture tail water has small occupied area, low operation cost and investment cost, can realize effective utilization of resources, is ecological and environment-friendly, does not produce secondary pollution to the environment, has good treatment effect on the aquaculture tail water, and ensures that the water quality is stable and reaches the standard.

Example 2

Based on the structure of embodiment 1, as shown in fig. 2, the ecological ditch 1 comprises an ecological packing layer and emergent aquatic plants planted on the ecological packing layer, the ecological packing layer comprises a planting soil layer I11 and a gravel layer 12 which are sequentially arranged from top to bottom, the ecological packing plays a role in filtering and adsorbing pollutants, and the bottom and the periphery of the ecological ditch 1 are both provided with an impermeable layer I13. The impermeable layer I13 is wrapped by geotextile, the geotextile adopts two cloth and a film, the specification is 200 g/square meter, the impermeable effect can be effectively achieved, and the infiltration of aquaculture water into the ground can be prevented; the ecological filler plays a role in filtering and adsorbing pollutants; the emergent aquatic plants have the effects of removing nutrient substances and enhancing ecological landscaping, mainly comprise rhizoma acori graminei, siberian iris, allium fistulosum, reed and the like, have strong decontamination capability, drought resistance, do not die in winter, and have good landscaping collocation effect.

The gradient of the wetland unit 23 is 0.5% -1%, that is, the gradient from the water inlet end to the water outlet end of the wetland is 0.5% -1%, water flows automatically from the water inlet end to the water outlet end through gravity, and meanwhile, the water pump 29 is adopted for draining water, so that multi-stage lifting can be avoided, and energy consumption is reduced; the wet land unit 23 has an aspect ratio of 2:1, the filler can be better utilized, and the water quality purifying effect is optimal; the area of the horizontal subsurface flow constructed wetland 2 is calculated by water quantity, the hydraulic retention time is 1-3 days, and the surface hydraulic load of the wetland unit 23 reaches 0.3-1m < 3 >/(m < 2 >. D).

In addition, the periphery of the wetland unit 23 is a bricked wall body, the height of the wall body is 1.5-2m, and the height of the wall body is 0.2-0.3m higher than the ground; preferably, the height of the wall body is 1.6m, and the water depth is 1.5m; and the periphery and the bottom of the wall body of the wetland unit 23 are respectively provided with a second impermeable layer 235, and the wetland filler layer is arranged in the second impermeable layer 235. The second impermeable layer is wrapped by geotextile, the geotextile adopts two first films, the specification is 200 g/square meter, and the impermeable effect can be effectively achieved.

As shown in fig. 3, the wetland packing layer includes a second planting soil layer 231, an upper gravel layer 232, and a main packing layer 233, which are sequentially disposed from top to bottom, wherein two sides of the main packing layer 233 are provided with side gravel layers 234, the side gravel layers 234 are in right triangle shapes, and the slope ratio of the inner slopes is 1/3-1/2. Gravel is arranged at two ends of the water inlet and outlet of the wetland unit, so that the blockage of the water inlet end and the water outlet end of the wetland unit can be prevented.

In the above structure, the gravel particle size of the side gravel layer 234 is larger than the gravel particle size of the upper gravel layer 232, the gravel particle size of the upper gravel layer 232 is 5-10mm, and the gravel particle size of the side gravel layer 234 is 80-120mm, so as to achieve a multi-level removal effect. In addition, the main filler layer 233 is a filler layer mixed by zeolite, volcanic rock and embedded microorganism filler, the mixing ratio of the zeolite, the volcanic rock and the embedded microorganism filler is 1:2:1, the mixing particle size is 10-80 mm, and the filtering and adsorbing effects are good.

In addition, as shown in fig. 3-4, one side of the bottom of the wetland unit 23 is provided with a water distribution pipeline 25 communicated with the water inlet channel 21, and the other side is provided with a water collecting pipeline 26 communicated with the water outlet channel 22, wherein the water distribution pipeline 25 and the water outlet pipeline 26 are oppositely arranged below the side gravel layer 234, and the side gravel layer 234 can enable water to better enter the water distribution pipeline 25 and the water collecting pipeline 26 so as to prevent blockage; and the water distribution pipeline 25 of each wetland unit 23 is provided with an independent water inlet valve 27, and the water collection pipeline 26 of each wetland unit 23 is provided with an independent water outlet valve 28. The water distribution pipeline 25 plays a role in evenly distributing tail water to each position of the wetland, the water collecting pipeline 26 mainly plays a role in collecting the treated tail water, the water inlet valve 27 controls the tail water to enter the wetland unit 23, the water outlet valve 28 controls the tail water to be discharged out of the wetland unit 23, so that the wetland can be effectively and fully operated, and the best pollutant removal effect is achieved. The water distribution pipeline 25 and the water outlet pipeline 26 are uniformly distributed, and the distance between the pipelines is 30-60cm; the water distribution pipeline 25 and the water outlet pipeline 26 are provided with a plurality of water passing holes which are uniformly distributed, the aperture of each water passing hole is 10mm, and the interval distance is about 30 cm; the same circumference can be provided with one water passing hole towards the bottom, or two water passing holes and the bottom are symmetrically arranged at two sides of the pipeline at 45 degrees.

In addition, as shown in fig. 3 and 5, the sludge discharging mechanism 24 includes a membrane pouring pipe 241 and a sludge outlet valve 242, the membrane pouring pipe 241 is disposed at the bottom of the wetland units 23 and is located about 20cm below the water collecting pipe 26, and a separate sludge outlet valve 242 is disposed on the membrane pouring pipe 241 of each wetland unit 23. The pouring film tube 241 mainly plays a role of discharging bottom sludge, and the sludge discharge valve 242 controls discharge of wetland sludge.

The invention also provides an operation method of the ecological system of the aquaculture tail water, which comprises the following steps:

s1, when the system starts to operate, water in the ecological ditch 1 is discharged into the horizontal subsurface flow constructed wetland 2, so that the water level of the wetland rises to a position 10cm below the wetland packing layer, and after the system is stabilized, water is continuously fed to rise to the surface of the wetland packing layer;

s2, in normal operation, opening the water inlet valve 27 and the water outlet valve 28, closing the mud outlet valve 242, automatically treating the culture tail water by the horizontal subsurface flow constructed wetland 2, and discharging the treated tail water into a river channel or a culture pond; the treated aquaculture tail water can be reused for aquaculture;

s3, the horizontal subsurface flow constructed wetland 2 adopts an intermittent operation mode, and a plurality of wetland units 23 work intermittently in turn, so that the long-acting operation of the wetland is ensured; for example, a horizontal subsurface flow constructed wetland comprises 4 wetland units 23: A. b, C, D wetland units, such as an operation A and B wetland, a closing of a C and D wetland, or an operation A wetland, a closing of a B, C and D wetland, or an operation A, B and C wetland, a closing of a D wetland, intermittent operation of the wetland and proper drying of the wetland, can enable the substrate to have a rest, ensure the aerobic state of the substrate, avoid excessive accumulation of extracellular polymers, and thus slow down the blockage of the substrate.

S4, after the device is normally operated for a certain time, starting the sludge discharging mechanism 24 to discharge sludge, opening the water inlet valve 27 and the sludge outlet valve 242, closing the water outlet valve 28, and discharging the bottom sludge of the wetland unit 23 out of the wetland through hydraulic flushing to prevent the wetland from being blocked;

s5, in winter, the wetland is kept at a high water level from the ecological ditch 1 or an external river channel, so that the survival rate of plants and the temperature of the wetland are ensured, and a certain heat preservation effect is achieved;

s6, harvesting plants in the ecological canal 1 and the horizontal subsurface flow constructed wetland 2 in time during season replacement, preventing secondary pollution caused by plant withering and spoiling, and reseeding when the plant growth density is insufficient.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

Claims (10)

1. An ecological system of aquaculture tail water, characterized in that: the ecological ditch is transformed by the ditch of the cultivation area; the horizontal subsurface flow constructed wetland is reformed by a pond or a peripheral river channel of a cultivation area and comprises a water inlet channel, a book outlet channel and a wetland, wherein the water inlet channel and the water outlet channel are oppositely arranged at two sides of the wetland, the water inlet channel is connected with the ecological channel through a drainage pipeline, the water outlet channel is provided with a water pump, and the wetland comprises a plurality of wetland units connected in parallel; the wetland unit comprises a wetland packing layer and plants planted above the wetland packing layer, wherein the plants are emergent aquatic plants and/or floating plants, and a mud discharging mechanism is further arranged at the bottom of the wetland unit.

2. An aquaculture tail water ecosystem according to claim 1 wherein: the ecological ditch comprises an ecological packing layer and emergent aquatic plants planted on the ecological packing layer, the ecological packing layer comprises a planting soil layer I and a gravel layer which are sequentially arranged from top to bottom, and the bottom and the periphery of the ecological ditch are both provided with an impermeable layer I.

3. An aquaculture tail water ecosystem according to claim 1 wherein: the slope of the wetland unit is 0.5% -1%, and the length-width ratio is 2:1, a step of; the surface hydraulic load of the wetland unit is 0.3-1m < 3 >/(m < 2 >. D).

4. An aquaculture tail water ecosystem according to claim 1 wherein: the wetland packing layer comprises a planting soil layer II, an upper gravel layer and a main packing layer which are sequentially arranged from top to bottom, wherein two sides of the main packing layer are provided with side gravel layers, the side gravel layers are in right triangle shapes, and the slope ratio of the inner inclined surfaces is 1/3-1/2.

5. The aquaculture tail water ecosystem according to claim 4 wherein: the gravel grain size of the side gravel layer is larger than that of the upper gravel layer, the gravel grain size of the upper gravel layer is 5-10mm, and the gravel grain size of the side gravel layer is 80-120mm.

6. The aquaculture tail water ecosystem according to claim 4 wherein: the main filler layer is a filler layer mixed by zeolite, volcanic rock and embedded microorganism filler, the mixing ratio of the zeolite, the volcanic rock and the embedded microorganism filler is 1:2:1, and the mixing particle size is 10-80 mm.

7. An aquaculture tail water ecosystem according to claim 1 wherein: the periphery of the wetland unit is a bricked wall body, the height of the wall body is 1.5-2m, and the height of the wall body is 0.2-0.3m higher than the ground; and the periphery and the bottom of the wall body of the wetland unit are provided with a second impermeable layer, and the wetland filler layer is arranged in the impermeable layer.

8. An ecological system of aquaculture tail water according to claim 1 or 4 characterized in that: one side of the bottom of the wetland unit is provided with a water distribution pipeline communicated with the water inlet channel, the other side of the bottom of the wetland unit is provided with a water collecting pipeline communicated with the water outlet channel, and the water distribution pipeline and the water outlet pipeline are oppositely arranged below the side gravel layer; the water distribution pipeline and the water outlet pipeline are uniformly distributed, and the distance between the pipelines is 30-60cm; a plurality of water passing holes which are uniformly distributed are formed in the water distribution pipeline and the water outlet pipeline; and the water distribution pipeline of each wetland unit is provided with an independent water inlet valve, and the water collection pipeline of each wetland unit is provided with an independent water outlet valve.

9. An aquaculture tail water ecosystem according to claim 1 wherein: the mud discharging mechanism comprises a membrane pouring pipe and mud discharging valves, wherein the membrane pouring pipe is arranged at the bottom of each wetland unit and positioned below the water collecting pipeline, and each wetland unit is provided with an independent mud discharging valve.

10. Method of operating an ecosystem of an aquaculture tail water according to any of claims 1 to 9, comprising the steps of:

s1, when the system starts to operate, water in the ecological ditch is discharged into the horizontal subsurface flow constructed wetland, so that the water level of the wetland rises to a position 10cm below the wetland packing layer, and after the system is stabilized, water is continuously fed to rise to the surface of the wetland packing layer;

s2, when the system operates normally, a water inlet valve and a water outlet valve are opened, a mud outlet valve is closed, the horizontal subsurface flow constructed wetland automatically treats the culture tail water, and the treated tail water is discharged into a river channel or a culture pond;

s3, the horizontal subsurface flow constructed wetland adopts an intermittent operation mode, and a plurality of wetland units work intermittently in turn, so that the long-acting operation of the wetland is ensured;

s4, starting a sludge discharge mechanism to discharge sludge after one end of normal operation, opening a water inlet valve and a sludge outlet valve, closing the water outlet valve, and discharging the sludge of the wetland unit out of the wetland through hydraulic flushing;

s5, in winter, the wetland is kept at a high water level from the ecological canal or an external river, so that the survival rate of plants and the temperature of the wetland are ensured;

s6, harvesting plants in the ecological canal and the horizontal subsurface flow constructed wetland in time during season replacement, and reseeding when the plant growth density is insufficient.