Aquaculture tail water treatment method based on biological method

Abstract

The invention discloses an aquaculture tail water treatment method based on a biological method, which comprises the treatment of aquaculture tail water based on tail water pretreatment and microorganism co-treatment, and specifically comprises the following steps: S1, tail water collection: arranging a tail water collection chamber by establishing a water channel; s2, a grating and a screen are sequentially arranged at a water outlet of the breeding tail water and a water inlet of the tail water collecting chamber; s3, chemical reagents are added into the tail water passing through the grid and the screen in the S2 for organic matter oxidation; s4, arranging a microbial reaction tank, cultivating activated sludge, feeding the tail water treated in the step S3 into a biological reaction tank, carrying out primary biological reaction through the activated sludge in the biological reaction tank, and adsorbing and decomposing pollutants; s5, constructing a wetland pond, discharging the tail water treated in the step S4 into the wetland pond, and performing final decomposition treatment on the tail water through an internal wetland bed and plants; and S6, feeding water in the wetland into the aquaculture pond for use. Compared with the prior art, the aquaculture tail water treatment method based on the biological method has the advantages that operation and use are convenient, tail water treatment can be efficiently carried out, and tail water recycling is convenient.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture tail water treatment, and in particular to an aquaculture tail water treatment method based on a biological method. Background Art

[0002] Aquaculture tailwater refers to water in which, due to the metabolism and accumulation of excrement, feed residues, drug residues and other substances of fish and other organisms during the aquaculture process, the content of harmful substances such as ammonia nitrogen, nitrite, hydrogen sulfide in the water body increases, the water quality deteriorates, and has adverse effects on farmed organisms.

[0003] Therefore, the tail water generated during the aquaculture process causes harm to the surrounding water bodies and ecological environment, which has seriously restricted the sustainable development of the industry. It is urgent to solve the technical problems of aquaculture tail water treatment.

[0004] At present, factory-scale recirculating aquaculture, as an advanced aquaculture model, has obvious advantages in terms of intensive aquaculture, water resource utilization, aquaculture effluent discharge control, land utilization rate, healthy aquaculture effect, product quality and safety, etc. However, in the subsequent aquaculture effluent treatment, conventional treatment processes can only treat ammonia nitrogen, nitrite nitrogen, and suspended solids, but cannot treat nitric nitrogen components, which affects the water quality of aquaculture circulating water and will cause pollution and damage to the environment after discharge. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the above technical defects and provide a biological-based aquaculture tailwater treatment method which is easy to operate and use, can efficiently treat tailwater, and facilitate tailwater reuse.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is: a method for treating aquaculture tailwater based on biological method, including treating aquaculture tailwater based on tailwater pretreatment and microbial co-treatment, specifically comprising the following steps: S1: Tailwater collection, by setting up a tailwater collection chamber by establishing a waterway; S2: grilles and screens are sequentially arranged at the outflow port of the aquaculture tail water and the water inlet of the tail water collection chamber; S3: Add chemical reagents to the tail water passing through the grid and screen in S2 to oxidize organic matter; S4: Set up a microbial reaction tank to cultivate activated sludge, send the tail water treated in S3 to the biological reaction tank, and conduct preliminary biological reaction through the activated sludge inside to adsorb and decompose pollutants; S5: construct a wetland pond to discharge the tailwater treated in S4 into the wetland pond, and finally decompose and treat the tailwater through the internal wetland bed and plants; S6: Send the water in the wetland pond to the aquaculture pond for use.

[0007] Preferably, S2 includes filtering the aquaculture tail water through a rotating grid to remove suspended solids, impurities and large suspended particles, and the filtered tail water is filtered through a screen for a second time and then sent to a tail water collection chamber.

[0008] Preferably, the chemical reagent in S3 includes one or more of coagulant, ozone, hydrogen peroxide, and potassium permanganate; The method also includes processing of byproducts, wherein the byproducts include residual ozone and decomposition products of hydrogen peroxide, and the processing of the byproducts includes using any one of aeration processing and activated carbon adsorption.

[0009] Preferably, the chemical reagents are coagulants and hydrogen peroxide, and the coagulants are added to make the suspended matter and colloidal substances coagulate into flocs and precipitate, and hydrogen peroxide is added after precipitation to oxidize and degrade organic matter in the tail water into inorganic matter; The coagulant includes aluminum salt, iron salt, organic polymer or a combination of one or more of these.

[0010] Preferably, emergent plants and submerged plants are also planted in the wetland pond, with the emergent plants accounting for 3-8% of the wetland area and the submerged plants accounting for 10-15% of the wetland area.

[0011] Preferably, the cultivation of the activated sludge in S4 includes adding nutrients to optimize the growth of microorganisms, and during tail water treatment, gradually increasing the tail water treatment load to enhance the removal efficiency.

[0012] Preferably, an aeration device is added in the biological reaction tank.

[0013] Preferably, the wetland pond further comprises a multi-stage wetland unit, and a tailwater filtration module is further arranged between adjacent wetland units, comprising a coarse sand layer, a gravel layer, a sand and gravel cushion layer, an activated carbon layer, and a biological filter membrane.

[0014] Preferably, the emergent plants include reeds, cattails, reed bamboo, and canna, and the submerged plants include duckweed and foxtail algae.

[0015] Preferably, the last-level wetland pond is also connected to a water quality monitoring module to monitor the data of dissolved oxygen, pH value, ammonia nitrogen, nitrite, nitrate, total phosphorus and total nitrogen in the pond.

[0016] The advantages of the present invention compared with the prior art are: the present invention uses water pretreatment and microbial co-treatment technology, which has the advantages of high treatment efficiency, stable and reliable operation, and green environmental protection. At the same time, the present invention reduces the subsequent impact on the microbial reaction stage by treating the residues in the tail water. At the same time, the present invention additionally adds a wetland pond that can be connected back to aquaculture. Through the multi-stage setting inside and the tail water filtration module arranged between the multi-stage ponds, the water quality is treated, and the data is monitored by the water quality monitoring module before being discharged to the aquaculture pond for utilization, thereby reducing the water cost and providing a complete tail water treatment process. DETAILED DESCRIPTION

[0017] References to embodiments of the present invention will now be provided in detail, one or more examples of which are described below. Each example is provided as an explanation rather than a limitation of the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope or spirit of the present invention. For example, a feature illustrated or described as part of one embodiment may be used in another embodiment to produce a further embodiment.

[0018] The terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0019] Except as shown in the operating examples or otherwise indicated, all numbers used in the specification and claims to indicate the amount of ingredients, physicochemical properties, etc. are understood to be adjusted by the term "about" in all cases. For example, therefore, unless otherwise indicated, the numerical parameters listed in the above specification and the attached claims are approximate values, and those skilled in the art can use the teachings disclosed herein to seek to obtain the desired properties and appropriately change these approximate values. The use of numerical ranges expressed as endpoints includes all numbers within the range and any range within the range, for example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4 and 5, etc.

[0020] As shown in combination, a method for treating aquaculture tailwater based on biological methods includes treating aquaculture tailwater based on tailwater pretreatment and microbial co-treatment, and specifically includes the following steps: S1: collecting tailwater, setting up a tailwater collection chamber by establishing a waterway; S2: setting grids and screens at the discharge outlet of the aquaculture tailwater and the water inlet of the tailwater collection chamber in sequence; S3: adding chemical reagents to the tailwater passing through the grid and screen in S2 to oxidize organic matter; S4: setting up a microbial reaction tank, cultivating activated sludge, and sending the treated tailwater in S3 into the biological reaction tank, and performing preliminary biological reaction through the internal activated sludge to adsorb and decompose pollutants; S5: constructing a wetland pond, discharging the treated tailwater in S4 into the wetland pond, and finally decomposing and treating the tailwater through the internal wetland bed and plants; S6: sending the pool water in the wetland to the aquaculture pond for use.

[0021] In the present invention, step 2 includes filtering suspended solids, impurities and large suspended particles of aquaculture tail water through a rotating grid, and the filtered tail water is sent to a tail water collection chamber after secondary filtration through a screen. For ease of use, the chemical reagent in S3 includes one or more of coagulants, ozone, hydrogen peroxide, and potassium permanganate; and also includes treatment of by-products, the by-products include ozone residues and hydrogen peroxide decomposition products, and the by-product treatment includes using any one of aeration treatment and activated carbon adsorption.

[0022] The cultivation of activated sludge in S4 includes adding nutrients to optimize the growth of microorganisms. During tailwater treatment, the tailwater treatment load is gradually increased to enhance the removal efficiency. At the same time, an aeration device is added to the biological reactor.

[0023] In specific use, the chemical reagents are coagulants and hydrogen peroxide. The coagulant is added to make the suspended matter and colloidal substances condense into flocs and precipitate. After precipitation, hydrogen peroxide is added to oxidize and degrade the organic matter in the tail water into inorganic matter; the coagulant includes one or more combinations of aluminum salts, iron salts, and organic polymers.

[0024] In order to ensure the purification effect of the wetland pond, emergent plants and submerged plants are planted in the wetland pond. The ratio area of ​​emergent plants is 3-8% of the wetland area, and the area of ​​submerged plants is 10-15% of the wetland area. The wetland pond also includes multi-level wetland units, and a tailwater filtration module is arranged between adjacent wetland units, including a coarse sand layer, a gravel layer, a sand and gravel cushion layer, an activated carbon layer, and a biological filter membrane. The emergent plants include reeds, cattails, reed bamboo, and canna, and the submerged plants include duckweed and foxtail algae. The last-level wetland pond is also connected to a water quality monitoring module to monitor the data of dissolved oxygen, pH value, ammonia nitrogen, nitrite, nitrate, total phosphorus, and total nitrogen in the pond.

[0025] In the specific implementation of the present invention, first, aquaculture tail water is introduced into a collection chamber through a waterway, and preliminary filtration is performed using a grid and a screen to remove large particle impurities. Coagulant and hydrogen peroxide are added to the filtered tail water, the coagulant causes the suspended matter to condense and precipitate, and the hydrogen peroxide oxidizes and degrades organic matter.

[0026] The treated tail water then enters the microbial reaction tank, where the activated sludge adsorbs and decomposes pollutants. To ensure the activity of microorganisms, an aeration device is installed in the reaction tank to provide sufficient oxygen. As the treatment load gradually increases, the removal efficiency of microorganisms is enhanced.

[0027] The treated tail water is discharged into the wetland pond for final purification through the combined action of the wetland bed and plants. The wetland pond is planted with emergent plants and submerged plants, which are proportioned according to the absorption capacity and growth rate of pollutants to optimize the purification effect. After the tail water is treated in the wetland, water quality monitoring is carried out to ensure that various indicators such as dissolved oxygen, pH value, ammonia nitrogen, nitrite, nitrate, total phosphorus, total nitrogen, etc. meet the water use standards for aquaculture. Once the water quality meets the standards, the treated tail water can be sent back to the aquaculture pond for use, so as to achieve the recycling of tail water.

[0028] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0029] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0030] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0031] The present invention and its implementation methods are described above, and such description is not restrictive. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design structures and embodiments similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. A biological method for treating aquaculture tailwater, characterized in that: It includes the treatment of aquaculture tailwater based on tailwater pretreatment and microbial co-treatment, which specifically includes the following steps: S1: Tailwater collection, by setting up a tailwater collection chamber by establishing a waterway; S2: grilles and screens are sequentially arranged at the outflow port of the aquaculture tail water and the water inlet of the tail water collection chamber; S3: Add chemical reagents to the tail water passing through the grid and screen in S2 to oxidize organic matter; S4: Set up a microbial reaction tank to cultivate activated sludge, send the tail water treated in S3 to the biological reaction tank, and conduct preliminary biological reaction through the activated sludge inside to adsorb and decompose pollutants; S5: construct a wetland pond to discharge the tailwater treated in S4 into the wetland pond, and finally decompose and treat the tailwater through the internal wetland bed and plants; S6: Send the water in the wetland pond to the aquaculture pond for use.

2. The method for treating aquaculture tailwater based on biological method according to claim 1, characterized in that: The S2 includes filtering the aquaculture tail water through a rotating grid to remove suspended solids, impurities and large suspended particles, and the filtered tail water is filtered through a screen for secondary filtration and then sent to a tail water collection chamber.

3. The biological method for treating aquaculture tailwater according to claim 1, characterized in that: The chemical reagent in S3 includes one or more of coagulant, ozone, hydrogen peroxide, and potassium permanganate; The method also includes processing of byproducts, wherein the byproducts include residual ozone and decomposition products of hydrogen peroxide, and the processing of the byproducts includes using any one of aeration processing and activated carbon adsorption.

4. The biological-based aquaculture tailwater treatment method according to claim 3, characterized in that: The chemical reagents are coagulants and hydrogen peroxide. The coagulants are added to make the suspended matter and colloidal substances coagulate into flocs and precipitate. After precipitation, hydrogen peroxide is added to oxidize and degrade organic matter in the tail water into inorganic matter. The coagulant includes aluminum salt, iron salt, organic polymer or a combination of one or more of these.

5. The biological method for treating aquaculture tailwater according to claim 1, characterized in that: Emergent plants and submerged plants are also planted in the wetland pond, with the area of ​​the emergent plants accounting for 3-8% of the wetland area, and the area of ​​the submerged plants accounting for 10-15% of the wetland area.

6. The biological method for treating aquaculture tailwater according to claim 1, characterized in that: The cultivation of the activated sludge in S4 includes adding nutrients to optimize the growth of microorganisms, and during tail water treatment, gradually increasing the tail water treatment load to enhance the removal efficiency.

7. The biological-based aquaculture tailwater treatment method according to claim 6, characterized in that: An aeration device is also added in the biological reaction tank.

8. The biological-based aquaculture tailwater treatment method according to claim 5, characterized in that: The wetland pond also includes multi-level wetland units, and a tailwater filtration module is arranged between adjacent wetland units, including a coarse sand layer, a gravel layer, a sand and gravel cushion layer, an activated carbon layer, and a biological filter membrane.

9. The biological method for treating aquaculture tailwater according to claim 5, characterized in that: The emergent plants include reeds, cattails, reed bamboo, and canna, and the submerged plants include duckweed and foxtail algae.

10. The biological-based aquaculture tailwater treatment method according to claim 8, characterized in that: The last level of the wetland pond is also connected to a water quality monitoring module to monitor the data of dissolved oxygen, pH value, ammonia nitrogen, nitrite, nitrate, total phosphorus and total nitrogen in the pond.