Aquaculture tail water treatment system

Abstract

The utility model discloses an aquaculture tail water treatment system, which is characterized by comprising a plurality of filter units, a plurality of filter units, a plurality of filter units and a plurality of filter units, each filtering unit comprises a physical filtering layer and a biological filtering layer; the physical filter layer is arranged at the upstream of the biological filter layer; water firstly flows through the physical filter layer and then enters the biological filter layer; the physical filtering layer is used for filtering solid substances in a water body; the biological filtering layer is used for filtering chemical substances in a water body; the biological filter layer comprises a shell, a substrate is arranged in the shell, and the substrate comprises a plurality of sodium alginate pellets; the shell is in a porous column shape or a strip shape. The base is placed in the shell of the biological filter layer, the shell adopts a porous strip-shaped or columnar design, the contact area with a water body is increased, and the internal base can be replaced, that is, sodium alginate pellets can be replaced according to conditions, so that the tail water treatment system is ensured to be in a high-efficiency state.

Description

Technical Field

[0001] The utility model relates to the field of aquaculture tail water treatment, in particular to an aquaculture tail water treatment system. Background Art

[0002] With the rapid development of the aquaculture industry, a large amount of organic matter, suspended solids, etc. are contained in the aquaculture tail water generated in aquaculture. It belongs to eutrophic water. If the aquaculture tail water is directly discharged into natural water bodies, it will pollute the natural water bodies. Therefore, the aquaculture tail water needs to be treated before discharge and can only be discharged after reaching the discharge standard.

[0003] Generally, the aquaculture tail water mainly contains organic matter, nitrogen, phosphorus, etc., mainly showing water eutrophication. Its main characteristics are: there are more particulate suspended solids in the aquaculture tail water, and the particles of the suspended solids are larger. Once the water body is stationary, the particulate suspended solids are easy to precipitate. Most of the main pollutants such as nitrogen, phosphorus and organic matter are contained in the solids, and these indicators can be greatly reduced after filtration.

[0004] At present, there are also some treatment methods for aquaculture tail water, such as sedimentation tanks, filtration systems, etc., but the general treatment efficiency is low. Summary of the Utility Model

[0005] The purpose of the utility model is at least to provide an aquaculture tail water treatment system for solving the problem of low treatment efficiency of tail water in current aquaculture.

[0006] To achieve the above purpose, the first aspect of the utility model provides an aquaculture tail water treatment system, including: a plurality of filtering units, the plurality of filtering units are arranged in parallel and stacked in the water body; each of the filtering units includes a physical filtering layer and a biological filtering layer; the physical filtering layer is arranged upstream of the biological filtering layer; so that the water body first flows through the physical filtering layer and then enters the biological filtering layer; the physical filtering layer is used for filtering solid substances in the water body; the biological filtering layer is used for filtering chemical substances in the water body; the biological filtering layer includes a housing, a substrate is arranged inside the housing, and the substrate contains a plurality of sodium alginate balls; the housing is a porous column or strip.

[0007] Optionally, the physical filtering layer at least includes: a coarse filtering layer and a fine filtering layer. The coarse filtering layer is a grid layer for filtering large particles in the water body; the fine filtering layer is an activated carbon layer or a cotton layer; a distance of 5-20 cm is provided between the coarse filtering layer and the fine filtering layer.

[0008] Optionally, the sodium alginate balls are used for embedding microorganisms, and the embedded microorganisms include bacteria and microalgae.

[0009] Optionally, the thickness of the biological filtration layer is 5-30 cm; the thickness of the physical filtration layer is 5-30 cm.

[0010] Optionally, the embedding density of the microalgae is: 10 4 -10 8 cells / ml; the embedding density of the bacteria is: 10 4 -10 10 cells / ml.

[0011] Optionally, the sodium alginate content of the sodium alginate beads is 6%.

[0012] Optionally, a microbial culture medium is added into the sodium alginate beads, and the sodium alginate bead culture medium includes f / 2 culture medium and bacterial culture medium.

[0013] Optionally, the outer shell is provided with an inlet and an outlet for installing and discharging the substrate in the outer shell.

[0014] The second aspect of the present utility model provides a method for making the substrate in an aquaculture tail water treatment system. The method for making the sodium alginate beads embedding microorganisms includes: placing the sodium alginate beads embedding microalgae in a microalgae culture medium for culturing for 1-3 days, with a culture temperature of 20-30 °C and a light intensity of 100-150 Lux. Then place the cultured sodium alginate beads embedding microalgae in the biological filtration layer.

[0015] Optionally, the method for making the sodium alginate beads embedding microorganisms includes: dissolving 6% of sodium alginate in a microalgae culture medium to form a sodium alginate solution; adding 10% of a microalgae-containing culture solution with a microalgae density of 10 6 -10 10 cells / ml to the sodium alginate solution to form a microalgae mixture; dropping the microalgae mixture into a 3% CaCl2 solution and staying for 20-40 min to form the sodium alginate beads embedding microalgae.

[0016] Optionally, the physical filtration layer is provided with a cleaning device.

[0017] An aquaculture tail water treatment system provided by an embodiment of the present utility model is provided with a plurality of filtering units. Each filtering unit includes a physical filtering layer and a biological filtering layer. The physical unit first filters out impurities in the water body such as suspended matters and food residues in the tail water. The tail water filtered by the physical filtering layer is then filtered through the biological filtering layer. The sodium alginate beads in the biological filtering layer absorb and decompose the organic matters in the tail water, improve the eutrophication of the water body, and reduce the nitrogen and phosphorus content. In this way, through continuous treatment of the water body by a plurality of such filtering units, the aquaculture tail water finally meets the discharge standard. The present utility model first divides the treatment of tail water into physical and biological treatments, utilizes the different characteristics of the filtering layers, filters in stages, increases the filtering effect, first filters the solid matters in the water body, and then conducts biological treatment. Sodium alginate beads are added in the biological filtering layer. The sodium alginate beads are embedded with microorganisms, which can decompose and utilize the organic matters in the water body. Moreover, the sodium alginate beads are small in volume and can be in full contact with the tail water, which can accelerate the treatment efficiency of the tail water. The base is placed inside the outer shell of the biological filtering layer. The outer shell is designed in a porous strip or column shape to increase the contact area with the water body. And, the internal base can be replaced, that is, the sodium alginate beads can be replaced according to the situation to ensure that the tail water treatment system is in a high-efficiency state.

[0018] From the following detailed description of specific embodiments of the present utility model in conjunction with the accompanying drawings, those skilled in the art will become more clear about the above and other objects, advantages and features of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Some specific embodiments of the present utility model will be described in detail hereinafter with reference to the accompanying drawings in an exemplary but non-limiting manner. The same reference numerals in the drawings denote the same or similar components or parts. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0020] Figure 1 is a schematic diagram of the biological filtering layer of an aquaculture tail water treatment system in an embodiment of the present utility model.

[0021] Figure 2 is a schematic diagram of the physical filtering layer of an aquaculture tail water treatment system in an embodiment of the present utility model.

[0022] Figure 3 is a schematic diagram of an aquaculture tail water treatment system in an embodiment of the present utility model.

[0023] Figure 4 is a schematic diagram of an aquaculture tail water treatment system in an embodiment of the present utility model.

[0024] Figure 5 is a schematic cross-sectional view of the physical filtering layer of an aquaculture tail water treatment system in an embodiment of the present utility model. Detailed implementation manners

[0025] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] The following refers to Figures 1-5 a partial schematic diagram of an aquaculture tail water treatment system provided by an embodiment of the present utility model, Figure 1 a biological filtration layer housing 10 in the shape of a cuboid, with multiple holes provided on the housing 10. The housing can also be mesh-shaped, as long as it can keep the internal substrate inside the housing without flowing out. An inlet and outlet 11 is provided at one end of the housing for convenient replacement of the substrate. The housing 10 is also cylindrical, and the thickness of the housing is maintained between 5 - 30 cm. If it is too thick, it is not conducive to the tail water passing through; if it is too thin, it is not conducive to the internal substrate decomposing the organic matter in the water body.

[0027] Figure 2 a housing 20 of a physical filtration layer in the shape of a cuboid. The physical filtration layer 20 is similar to the housing of the biological filtration layer 10, except that the internal filling is different, and multiple holes are also provided on the housing 20. An inlet and outlet 21 is also provided on the housing 20 of the physical filtration layer for convenient replacement of the internal filtering substances. As Figure 5 shown, the physical filtration layer is divided into a coarse filtration layer 22 and a fine filtration layer 23. The filling in the housing of the coarse filtration layer 22 is a grid layer for filtering large particles in the water body; the filling in the housing of the fine filtration layer 23 is an activated carbon layer or a cotton layer; a space 24 is provided between the coarse filtration layer and the fine filtration layer, and the distance of the space 24 is between 1 - 10 cm. In this way, there is a water storage space in the middle, which can increase the filtration efficiency. The arrow direction in the figure is the water flow direction. The water flow first passes through the coarse filtration layer 22 to filter out large particles, and then passes through the fine filtration layer 23 to filter out small particles, so as to filter the tail water separately and improve the filtration efficiency.

[0028] The above-mentioned housing can be reused as long as the internal substances are replaced, which is more energy-saving and environmentally friendly.

[0029] As Figure 3 、 Figure 4 shown, the biological filtration layer B and the physical filtration layer A can have various different setting manners. However, the physical filtration layer A is placed first, and the arrow direction is the water flow direction. Figure 3 In it, the biological filtration layer B and the physical filtration layer A are alternately and repeatedly arranged. Figure 4First, set the physical filtration layer A, and then set multiple biological filtration layers B. The number of biological filtration layers A and physical filtration layers B can be determined according to the situation, so that the system can be more flexible and suitable for more different tail water treatment requirements. The water flow first passes through the physical filtration layer A to filter out physical particles and other substances in the tail water, and then passes through the physical filtration layer B for filtration to complete the absorption of substances such as nitrogen and phosphorus in the tail water, reduce the biological oxygen demand of the water body, and make it meet the discharge standard. Among them, there is also a gap between the biological filtration layer B and the physical filtration layer A, which can also form a space with stored water in the middle to accelerate the filtration efficiency.

[0030] A cleaning device can be set on the water inlet side of the physical filtration layer A. Since the physical filtration layer is set upstream, it is easy to be blocked by large particles or others, reducing the efficiency of the system's water treatment. By regularly cleaning with the cleaning device, the water treatment efficiency can be improved and the service life of the system can be increased. Among them, the cleaning device can be a mechanical wall, one end is connected to the side of the outer shell of the physical filtration layer A, and the other end is provided with a cleaning head, which is similar to a broom and can clean the blockages on the outer surface of the physical filtration layer A. A motor can be set inside the cleaning device, the motor is connected to the power supply, and the movement of the motor makes the cleaning device move to complete the cleaning movement, which can reduce manpower and is more convenient.

[0031] The substrate in the biological filtration layer is sodium alginate beads, and microorganisms are embedded in the sodium alginate beads. The types of microorganisms include bacteria and microalgae. Among them, the bacteria can be Bacillus, Nitrobacter, Denitrifying bacteria, etc.; the microalgae can include freshwater microalgae or marine microalgae, such as Chaetoceros muelleri, Dunaliella salina, Isochrysis galbana, Nannochloropsis oculata, etc.

[0032] Among them, the sodium alginate beads are prepared by dissolving sodium alginate in f / 2 culture medium or bacterial culture medium, then adding microalgae culture medium or bacterial culture medium to the sodium alginate solution, stirring evenly, and dropping the sodium alginate solution mixed with microorganisms into 3% CaCl2 solution in a dripping manner to form sodium alginate beads.

[0033] Experiments show that the best amount of sodium alginate used is 6%, and the forming effect of the sodium alginate beads is good. The embedding density of microalgae in the sodium alginate beads is: 10 4 -10 8 cells / ml; the embedding density of the bacteria is: 10 4 -10 10 cells / ml.

[0034] The components of the microalgae culture medium should meet the nutritional requirements for the growth of microalgae, including but not limited to nitrogen source, phosphorus source, trace elements, vitamins, etc.

[0035] The f / 2 medium is a commonly used microalgae medium formulation, and its components can be adjusted according to actual situations to meet the different nutritional requirements of specific microalgae species.

[0036] The experiment on the production of sodium alginate beads is as follows:

[0037] 1. Wash a 500 mL beaker, put 200 mL of f / 2 culture medium into it. According to the experimental design, weigh sodium alginate respectively, stir it evenly with a glass rod as much as possible, and sterilize it at 120 °C for 30 min. Cool it to room temperature, and inoculate the algal solution at a ratio of 20%, then stir evenly.

[0038] 2. Weigh 90 g of CaCl2, put it into 3 L of physiological saline (0.9% NaCl solution), stir to dissolve it, and divide it into 1000 mL beakers, with 500 mL of solution in each beaker. Put them into the autoclave for sterilization and cool for later use.

[0039] 3. In the sterile workbench, use a 1 mL syringe to suck the mixed liquid of sodium alginate and algal solution, and drop it into the CaCl2 solution, so that the sodium ions in sodium alginate react with the calcium ions in CaCl2, and finally form a calcium alginate gel network structure to fix the algal cells. The reaction time is 30 min.

[0040] 4. Scoop out the beads, then rinse them three times with sterile water to remove the residual CaCl2 solution, and store them sealed at room temperature in a 250 mL conical flask.

[0041] 5. Randomly select and measure the diameters of the beads with three different sodium alginate contents, then soak them in the f2 medium for 2 h and measure the diameters again.

[0042] 6. From the analysis of the forming effect of the beads, when the sodium alginate content is 6%, the effect is the best, with high mechanical strength, fast forming speed, and small change in the culture medium. The forming effect of the beads is the best. Therefore, in this experiment, the ratio of the beads for embedding microalgae is selected as 6% sodium alginate, and crosslinking in the CaCl solution for 30 min.

[0043] The effects of sodium alginate and polyvinyl alcohol on the immobilized beads. The optimal conditions obtained are 6% sodium alginate, fixed in 3% CaCl2 solution for 30 min, and the maximum number of embedded algal cells is 10 6 cell / mL.

[0044] The above is only a preferred specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. An aquaculture tail water treatment system, characterized in that, Comprising: A plurality of filtration units, which are arranged side by side and stacked in the water body; Each of the filtration units includes a physical filtration layer and a biological filtration layer; The physical filtration layer is arranged upstream of the biological filtration layer; So that the water body first flows through the physical filtration layer and then enters the biological filtration layer; The physical filtration layer is used to filter solid substances in the water body; The biological filtration layer is used to filter chemical substances in the water body; The biological filtration layer includes a housing, and a substrate is arranged inside the housing, and the substrate is a plurality of sodium alginate balls; The housing is a porous columnar or strip shape; The sodium alginate balls are sodium alginate balls embedded with microorganisms; The physical filtration layer at least includes: a coarse filtration layer and a fine filtration layer; The coarse filtration layer is a grid layer for filtering large particles in the water body; The fine filtration layer is an activated carbon layer or a cotton layer; There is a distance of 5-20 cm between the coarse filtration layer and the fine filtration layer.

2. The aquaculture tail water treatment system according to claim 1, characterized in that The thickness of the biological filtration layer is 5-30 cm; The thickness of the physical filtration layer is 5-30 cm.

3. The aquaculture tail water treatment system according to claim 1, characterized in that The housing is provided with an inlet and an outlet for installing and discharging the substrate inside the housing.

4. The aquaculture tail water treatment system according to claim 1, characterized in that The physical filtration layer is provided with a cleaning device.

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