CN115231710A - A kind of aquaculture tail water purification system and purification method - Google Patents

Abstract

The invention discloses a system and a method for purifying aquaculture tail water. This aquaculture tail water clean system includes: the device comprises a composite wetland purification area and a recirculating aquaculture area, wherein the rear end of the recirculating aquaculture area is communicated with the front end of the composite wetland purification area, and the rear end of the composite wetland purification area is communicated with the front end of the recirculating aquaculture area. According to the invention, the circulating water culture area is additionally arranged at the rear end of the composite wetland purification area, and the biomass and activity of plants and microorganisms in the composite wetland purification area are maintained during the culture period by using pollutants such as nitrogen and phosphorus generated by the circulating water culture area; in the tail water treatment period in winter, the high biological activity of the purification area of the composite wetland can finish the effective treatment of the culture tail water in the common culture area; in addition, before a large amount of tail water of the aquaculture pond is discharged, aquaculture products in the recirculating aquaculture area can be harvested and sold on the market, and the economic loss caused by building a composite wetland purification area and a recirculating aquaculture area can be compensated.

Description

A kind of aquaculture tail water purification system and purification method

technical field

The invention relates to the technical field of aquaculture tail water purification, in particular to an aquaculture tail water purification system and a purification method.

Background technique

China is the world's largest aquaculture country. However, due to the limitation of aquaculture concepts and the backwardness of aquaculture technology, it is difficult to achieve scientific norms in actual production, resulting in pollution of aquaculture water. On the one hand, the pollutants generated in the breeding process will cause the immune function of the farmed animals to decline, be susceptible to diseases, and affect the quality of aquatic products. Therefore, the effective treatment of the tail water of aquaculture ponds has become an indispensable link in the current pond aquaculture process.

At present, the aquaculture tail water purification system is mainly composed of units such as multi-level constructed wetlands or biological purification ponds. The main principle is to use substrates, plants and microorganisms to adsorb or absorb pollutants. However, when constructing this type of aquaculture treatment system for tail water treatment, it is often necessary to utilize 5%-10% of the area of the aquaculture pond. The pond renovation will directly reduce the original aquaculture area and affect the economic income of fishermen, so it is difficult to be accepted by farmers. In addition, according to the current law of freshwater pond culture, the pond tail water is mainly arranged to be discharged in winter, and the discharge in other seasons is very small. Therefore, in the non-drainage season, the aquaculture tail water purification system has no external water inflow, the water body of the tail water purification system is in a static state, and the long-term absence of pollutant input will cause a decrease in the number and activity of various organisms, affecting the tail water during its use period. processing effect. If the water body is artificially propelled to maintain the activity of plants and microorganisms during the cultivation period of the system, additional operating costs will be incurred.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above-mentioned technical deficiencies, propose a kind of aquaculture tail water purification system and purification method, solve the problem that the aquaculture tail water purification system in the prior art reduces the original breeding area, affects the economic income of fishermen, and the non-drainage season is long-term No pollutant input will cause the reduction of the number and activity of various organisms, and affect the technical problems of the tail water treatment effect during the use period.

A first aspect of the present invention provides an aquaculture tail water purification system, comprising: a composite wetland purification area and a recirculating aquaculture area, the rear end of the recirculating aquaculture area is communicated with the front end of the composite wetland purification area, and the rear end of the composite wetland purification area The end is communicated with the front end of the circulating aquaculture area.

The second aspect of the present invention provides an aquaculture system, comprising the aquaculture tail water purification system provided in the first aspect of the present invention and a common aquaculture area. The front end is communicated with the rear end of the composite wetland purification area.

A third aspect of the present invention provides a method for purifying aquaculture tail water, comprising the following steps:

During the breeding season, the general breeding area does not drain water, and the water in the complex wetland purification area and the circulating aquaculture area circulates itself;

During the drainage season, the general aquaculture area is drained, and the tail water discharged from the general aquaculture area enters the compound wetland purification area and enters the ordinary aquaculture area again after purification.

Compared with the prior art, the beneficial effects of the present invention include:

By adding a recirculating aquaculture area at the rear end of the compound wetland purification area, the present invention utilizes nitrogen, phosphorus and other pollutants generated in the recirculating aquaculture area to maintain the biomass and activity of plants and microorganisms in the compound wetland purification area during the breeding period; During the treatment period, the higher biological activity of the compound wetland purification area can complete the effective treatment of the tail water of the common aquaculture area; in addition, before the tail water of the aquaculture pond is discharged in large quantities, the aquaculture products in the recirculating aquaculture area can be harvested and marketed, bringing benefits. It can make up for the economic losses caused by the construction of complex wetland purification areas and recirculating aquaculture areas. It can be seen that the present invention can maintain the effect of aquaculture tail water treatment, reduce the economic loss of constructing an aquaculture tail water treatment system, ensure a good aquaculture water environment, and realize the overall water resource recycling.

Description of drawings

Fig. 1 is the schematic diagram of the water flow circulation of the aquaculture tail water purification system in the conventional breeding season;

Fig. 2 is a schematic diagram of the water flow circulation of the aquaculture tail water purification system during the winter drainage period;

FIG. 3 is a schematic structural diagram of an embodiment of a culture bucket, a sewage pump and a solid-liquid separation tower in a recirculating aquaculture area.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

1-3, a first aspect of the present invention provides an aquaculture tail water purification system, including: a complex wetland purification area 100 and a recirculating aquaculture area 200, the back end of the recirculating aquaculture area 200 and the complex wetland purification area The front end of the 100 is connected, and the rear end of the composite wetland purification zone 100 is communicated with the front end of the recirculating aquaculture zone 200, so that the water body in the recirculating aquaculture zone 200 is passed to the front end of the composite wetland purification zone 100, and after being processed by the composite wetland purification zone 100 From the rear end of the complex wetland purification zone 100 to the front end of the recirculating aquaculture zone 200 . The recirculating aquaculture area 200 needs to exchange or purify a part of the water regularly to ensure the stability of physical and chemical indicators such as salinity, alkalinity, pH, etc. in the recirculating aquaculture area 200, and to reduce the impact of toxic substances such as ammonia nitrogen on the aquaculture objects. The characteristics of the recirculating aquaculture area 200, the present invention takes advantage of this characteristic to pass the water body containing nitrogen, phosphorus and other pollutants generated by the recirculating aquaculture area 200 into the front end of the complex wetland purification area 100, and at the same time from the complex wetland purification area 100 The back-end supplementary clean water body enters the recirculating aquaculture area 200 . On the one hand, this operation can ensure the water environment quality of the recirculating aquaculture area 200, and on the other hand, by linking the recirculating aquaculture area 200 and the complex wetland purification area 100 to realize the water body circulation in the system during the breeding season, and maintain the complex wetland purification area 100 during the breeding period. The biomass and activity of internal plants and microorganisms; at the same time, the aquatic products harvested in the recirculating aquaculture area can be used to reduce the economic losses caused by the complex wetland purification area and the recirculating aquaculture area.

In the present invention, those skilled in the art should understand that the front or rear end of the composite wetland purification zone 100 refers to the water inlet or outlet of the composite wetland purification zone 100, and the front or rear end of the recirculating aquaculture zone 200 refers to the recirculating aquaculture zone 200 at the inlet or outlet.

In the present invention, the above-mentioned composite wetland purification area 100 includes at least one of a multi-stage sedimentation pond area, a constructed wet area, a submerged plant purification area or a biological brush area.

In some specific embodiments of the present invention, the above-mentioned composite wetland purification area 100 includes a first submerged plant purification area 101, a submerged artificial wet area 102, a biological brush area 103 and a second submerged plant purification area arranged in sequence along the circulation direction. 104.

In the present invention, the above-mentioned circulating aquaculture area 200 is a facility high-density aquaculture area.

Further, the above-mentioned facility high-density culture area includes at least one of a channel culture device, a container culture device, and a captive culture device.

In some specific embodiments of the present invention, the above-mentioned facility high-density breeding area includes a captive breeding device, and the captive breeding device includes a breeding barrel 201, a sewage pump 202 and a solid-liquid separation tower 203. The sewage outlet at the bottom of the breeding barrel 201 and the sewage discharge The water inlet of the pump 202 is communicated through the sewage pipeline, and the water outlet of the sewage pump 202 is respectively connected with the solid-liquid separation tower 203 and the front end of the composite wetland purification zone 100 through the sewage pipeline, and the connection is provided with a valve. Further, valve A is set on the sewage pipeline between the sewage pump 202 and the solid-liquid separation tower 203 , and valve B is set on the sewage pipeline between the sewage pump 202 and the front end of the composite wetland purification zone 100 . Further, the breeding barrel 201 is set in the water, and is provided with a water inlet hole, so that the clean water after being purified by the composite wetland purification zone 100 enters the breeding barrel 201 spontaneously through the water inlet hole under the action of the liquid level height difference.

In the present invention, the specific structures of the breeding barrel 201, the sewage pump 202, and the solid-liquid separation tower 203 are all in the prior art, which will not be repeated in the present invention.

In the present invention, the area of the circulating aquaculture area 200 is 15-25% of the total area of the aquaculture tail water purification system, and further is 20-25%. By designing the area of the recirculating aquaculture area 200 within this range, the present invention enables the pollution load generated by the recirculating aquaculture area 200 to meet the growth needs of the functional organisms in the complex wetland purification area 100 without generating new pollution.

The second aspect of the present invention provides an aquaculture system, comprising the aquaculture tail water purification system provided in the first aspect of the present invention and a common aquaculture area 300, the rear end of the common aquaculture area 300 is communicated with the front end of the composite wetland purification area 100, The front end of the common breeding area 300 communicates with the rear end of the complex wetland purification area 100 .

In some specific embodiments of the present invention, the front end of the common aquaculture area 300 communicates with the rear end of the complex wetland purification area 100 through the circulating aquaculture area 200 . This arrangement allows the water purified by the composite wetland purification zone 100 to enter the common aquaculture zone 300 through the circulating aquaculture zone 200 without additional ditches or pipes, and can also slow down the water flow.

In the present invention, the area of the aquaculture tail water purification system is 6-10% of the total area of the aquaculture system, further 10%. In the present invention, by setting the area of the aquaculture tail water purification system within this range, the composite wetland purification area 100 in the aquaculture tail water purification system can fully degrade the pollution load generated by the common aquaculture area 300, and to the greatest extent Guarantee the economic benefits of 300 common breeding areas.

In the present invention, the composite wetland purification area 100 , the circulating aquaculture area 200 and the common culture area 300 are connected by arranging ditches or pipes.

A third aspect of the present invention provides a method for purifying aquaculture tail water, comprising the following steps:

During the breeding season, the general breeding area 300 does not drain water, and the water in the complex wetland purification area 100 and the circulating aquaculture area 200 circulates itself;

During the drainage season, the general aquaculture area 300 is drained, and the tail water discharged from the general aquaculture area 300 enters the compound wetland purification area 100 and enters the general aquaculture area 300 again after being purified.

In the present invention, those skilled in the art should understand that both the breeding season and the drainage season are for common breeding areas, the traditional breeding season is generally spring, summer and autumn, and the drainage season is generally winter. However, those skilled in the art can also determine the breeding season and the drainage season according to the actual situation, which is not limited in the present invention.

In the present invention, the self-circulation of the water body in the above-mentioned composite wetland purification zone 100 and the circulating aquaculture zone 200 specifically includes: using the sewage pump 202 of the circulating aquaculture zone 200 to pump sewage, and after the sewage becomes clear, the clean water is sent to the composite wetland through the sewage pipeline. The front end of the wetland purification area 100; at the same time, the recirculating aquaculture area 200 supplements the clean water source from the rear end of the composite wetland purification area 100, so that the water flow forms a self-circulation. Further, the time for the sewage pump to pump clean water is 20-40 minutes.

In some preferred embodiments of the present invention, the tail water discharged from the common aquaculture area 300 enters the complex wetland purification area 100 and enters the common aquaculture area 300 again through the circulating aquaculture area 200 after being purified.

In the present invention, before the drainage season comes, the aquatic products in the recirculating aquaculture area 200 are caught and sold.

Example

Please refer to Figure 1-3, taking the area of 200 mu of aquaculture pond as an example, the average depth of aquaculture water is 2m, the details are as follows:

(1) Construction of an aquaculture tail water purification system: Select a 20-mu pond to build a complex wetland purification area 100 and a recirculating aquaculture area 200 to treat the tail water in the whole area, of which 15 mu are used as a complex wetland purification area, and the first place to be constructed respectively. Submerged plant purification area 101, submerged artificial wet area 102, biological brush area 103, and second submerged plant purification area 104; the remaining 5 mu will build a recirculating aquaculture area 200, which includes a breeding bucket 201 and a sewage pump 202 With the solid-liquid separation tower 203, the sewage outlet at the bottom of the breeding barrel 201 is communicated with the water inlet of the sewage pump 202 through the sewage pipeline, and the water outlet of the sewage pump 202 is respectively connected with the solid-liquid separation tower 203 and the front end of the composite wetland purification area 100 through the sewage pipeline. , There are valves at the connections. In this embodiment, a total of 20 captive tanks and 5 solid-liquid separation towers are erected.

(2) Purification method of aquaculture tail water: The general breeding area 300 and the recirculating aquaculture area 200 were cultured from the beginning of May 2019 for 180 days (6 months), and the breeding object was California perch. Open the valve A between the sewage pump 202 and the solid-liquid separation tower 203 every day, and run the sewage pump 202 to pump waste from the bottom of the breeding barrel 201 into the solid-liquid separation tower 203. After the discharged sewage becomes clear (once a day, each time about 3min) Close the valve A, open the valve B between the sewage pump 202 and the composite wetland purification area 100, and the sewage pump 202 works for another 30 minutes, so that the aquaculture water flows along the pipeline into the front end of the composite wetland purification area 100, and the culture bucket 201 pours into the The clean water treated by the composite wetland purification zone 100 operates as shown in Figures 1 and 3 at this time. Entering the low temperature period (about December, winter), the fish do not open their mouths. In order to prevent the decline of the fish body quality, the breeding ends before this. The fish products of the recirculating water aquaculture area 200 were first listed, and the work of the recirculating water aquaculture area 200 was completed. After that, the fish in the culture ponds were listed one after another. The water from the culture ponds passed through the drainage channel one by one into the compound wetland purification area 100, mainly using the compound wetland purification area. 100 purification, and then the clean water is transported to each culture pond through the intake channel, as shown in Figure 2.

In spring, summer and autumn (April-November), the ammonia nitrogen and nitrite at the back end of the complex wetland purification zone 100 are 0.22-2.35 mg/L and 0.06-0.18 mg/L, respectively, and the ammonia nitrogen and nitrite at the rear end of the recirculating aquaculture zone 200 Nitrates were 0.36-3.54 mg/L and 0.16-0.34 mg/L, respectively. In winter (mid-November), the fish in the recirculating aquaculture area will be put on the market. After half a month, the ponds will be drained one after another. After treatment in the complex wetland purification area, the tail water in winter can meet the requirements of "Freshwater aquaculture tail water discharge (draft for comments)" (SC/T9101-2007) the first-level standard.

In addition, through production measurement, the average output of California perch in 200 recirculating aquaculture areas can reach 1t/captive barrel (180 days of culture), and the total output of 20 captive barrels can reach 20t. The market price of California perch in that year (2019) was 30 yuan/kg Calculated, the output value of the California sea bass in the captive system can reach 600,000 yuan, and the total profit can reach 200,000 yuan, excluding water, electricity, fish medicine, fish fingerlings and other expenses. Through the investigation of fishermen, the output of ordinary ponds is 600-1000kg/mu (189 days of breeding), the net profit per unit area is only 7,000-10,000 yuan/mu, and the area loss of the 20-mu aquaculture tail water purification system is up to 20%. million. It can be seen that the recirculating aquaculture area constructed by the present invention can also make up for the economic loss caused by the land occupation of the composite wetland purification area 100 and the recirculating aquaculture area 200 .

Compared with the prior art, the beneficial effects of the present invention also include:

(1) During the breeding season, the water in the complex wetland purification area has no contact with the ordinary breeding area, and the water produced in the recirculating aquaculture area is used as the driving force for circulating water to drive the entire tail water purification system to circulate the water during the breeding season, maintaining even Improve the purification efficiency of the system for use in winter, and make up for the economic loss caused by the pond area occupied by the composite wetland purification area and the recirculating aquaculture area; The main function is to degrade pollutants to the maximum extent; in the non-aquaculture season, the recirculating aquaculture area does not operate, and the entire tail water purification system mainly plays a purification role in the composite wetland purification area, which is similar to the pollutant removal principle of the ordinary tail water purification system. There is no difference, but since the composite wetland purification area of the present invention is always in operation, the treatment effect will be significantly better than that of the ordinary tail water purification system.

(2) Ordinary aquaculture areas (aquaculture ponds) are generally only possible to perform in-situ water environment restoration (sprinkling micro-ecological reagents such as photosynthetic bacteria) during the breeding process, but not ex-situ restoration, that is, remove the water for treatment, if in order to maintain The system artificially promotes the water body due to the activity of plants and microorganisms during the breeding period. On the one hand, it will cause the problem of pumping costs. On the other hand, the amount of pollutants generated during the breeding process in the pond is small, which has little effect on the activity of plants and microorganisms. And the design is not economical either.

The specific embodiments of the present invention described above do not limit the protection scope of the present invention. Any other corresponding changes and modifications made according to the technical concept of the present invention shall be included in the protection scope of the claims of the present invention.

Claims (10)

1. an aquaculture tail water purification system, is characterized in that, comprises: compound wetland purification area and recirculating aquaculture area, the rear end of described recirculating aquaculture area is communicated with the front end of described compound wetland purifying area, and described compound wetland purification area. The rear end of the wetland purification area is communicated with the front end of the recirculating aquaculture area, so that the water body in the recirculating aquaculture area is passed into the front end of the compound wetland purification area, and after being processed by the compound wetland purification area, it is The rear end of the composite wetland purification area is connected to the front end of the circulating aquaculture area. 2. aquaculture tail water purification system according to claim 1, is characterized in that, described compound wetland purification area comprises at least one in multi-stage sedimentation pond area, artificial wet area, submerged plant purification area or biological brush area . 3. aquaculture tail water purification system according to claim 1, is characterized in that, described circulating aquaculture area is facilityized high-density culture area; Described facilityized high-density culture area comprises channel culture device, container culture device , at least one of captive breeding devices. 4. aquaculture tail water purification system according to claim 3, is characterized in that, described facility high-density culture area comprises captive culture device, and described captive culture device comprises culture bucket, sewage pump and solid-liquid separation tower, The sewage outlet at the bottom of the culture bucket is communicated with the water inlet of the sewage pump through a sewage pipeline, and the water outlet of the sewage pump is respectively connected with the solid-liquid separation tower and the front end of the composite wetland purification area through a sewage pipeline. , There are valves at the connections. 5. The aquaculture tail water purification system according to claim 1, wherein the area of the recirculating aquaculture area is 15-25% of the total area of the aquaculture tail water purification system. 6. an aquaculture system, is characterized in that, comprises the aquaculture tail water purification system and common culture area as described in any one of claim 1-5, the rear end of described common culture area and described compound wetland purification The front end of the area is communicated with, and the front end of the common breeding area is communicated with the rear end of the composite wetland purification area. 7 . The aquaculture system according to claim 6 , wherein the front end of the common aquaculture area is communicated with the rear end of the complex wetland purification area through the circulating aquaculture area. 8 . 8. The aquaculture system according to claim 6, wherein the area of the aquaculture tail water purification system is 6-10% of the total area of the aquaculture system. 9. an aquaculture tail water purification method, is characterized in that, comprises the following steps: During the breeding season, the general breeding area does not drain water, and the water in the complex wetland purification area and the circulating aquaculture area circulates itself; During the drainage season, the general aquaculture area is drained, and the tail water discharged from the general aquaculture area enters the compound wetland purification area and enters the ordinary aquaculture area again after purification; The aquaculture tail water purification method is realized by the aquaculture tail water purification system according to any one of claims 1-5. 10. The method for purifying aquaculture tail water according to claim 9, wherein the self-circulation of the water body in the composite wetland purification area and the recirculating aquaculture area comprises: using the sewage pump in the recirculating aquaculture area to pump sewage, After it becomes clear, the clean water is sent to the front end of the compound wetland purification area through the sewage pipeline; at the same time, the recirculating aquaculture area supplements the clean water source from the rear end of the compound wetland purification area, so that the water flow forms a self-circulation.

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