Combined type aquaculture tail water treatment device

Abstract

The invention discloses a combined type aquaculture tail water treatment device. A first treatment cavity, a second treatment cavity, a third treatment cavity, a fourth treatment cavity and a reservoir which are communicated with one another are arranged in the combined type aquaculture tail water treatment device; a biological flocculant feeding device is arranged in the first treatment cavity and can feed a biological flocculant into the first treatment cavity, an ozone micro-nano bubble generator is arranged in the second treatment cavity, and a microbiological treatment layer is arranged in the third treatment cavity and comprises immobilized microbiological beads; an activated carbon adsorption layer is arranged in the fourth treatment cavity. The device is optimized, so that the overall treatment efficiency is high, the removal effect on soluble pollutants is excellent, solid wastes and sludge are not easy to generate, secondary pollution is not caused, the operation is simple, and the popularization and application are easy.

Description

Technical Field

[0001] The invention relates to an aquaculture tail water treatment device, in particular to a composite aquaculture tail water treatment device. Background Art

[0002] With the development of the economy and the improvement of people's living standards, the demand for aquatic products has grown faster and faster in recent years, and the aquaculture industry has developed vigorously, but it has also brought serious ecological and environmental problems. In the process of aquaculture, the arbitrary discharge of aquaculture water is very common, causing serious damage to the aquatic ecosystem. The main pollutants in aquaculture wastewater are ammonia nitrogen, nitrite, organic pollutants, heavy metals, suspended particles, nutrients, pathogens, sulfides, phosphorus and pollutants. Under normal circumstances, the main pollutants can be roughly divided into three categories: organic carbon, nitrogen and phosphorus. If these pollutants in the aquaculture water body cannot be removed in time, it will have a certain impact on aquaculture. In addition, if reasonable discharge is not carried out, it will also cause eutrophication of the water body, further cause soil and groundwater pollution, and affect the quality of the ecological environment. Therefore, aquaculture wastewater treatment has positive significance.

[0003] Traditional methods for treating aquaculture wastewater mainly include physical methods, chemical methods and biological methods. Physical methods mainly involve sedimentation tanks, filtration tanks, flotation methods, etc.; chemical methods involve the use of chemical agents, oxidants, flocculation precipitation, etc. Compared with the other two methods, biological methods for treating aquaculture wastewater are more widely used. Existing technologies include sewage treatment technologies such as wetland technology, microbial technology, and biofilm infiltration treatment technology. Traditional aquaculture wastewater treatment facilities have high construction and maintenance costs, high costs, and high energy consumption, which is not conducive to sustainable development. They may also destroy the ecological balance of water bodies and affect aquatic organisms, making them difficult to promote and use on a large scale.

[0004] Therefore, traditional aquaculture wastewater treatment technologies generally have the problems of low efficiency, poor removal of soluble pollutants, easy generation of solid waste and sludge, which may lead to secondary pollution. In addition, there are also problems such as complex device operation and high preparation and maintenance costs. Summary of the invention

[0005] Based on this, in order to solve the problems of low efficiency, poor removal of soluble pollutants, easy generation of solid waste and sludge in the existing aquaculture wastewater treatment technology, which may lead to secondary pollution. In addition, there are also problems such as complex device operation and high preparation and maintenance costs. The present invention provides a composite aquaculture tailwater device, and the specific technical scheme is as follows:

[0006] A composite aquaculture tailwater treatment device comprises a box body, on which a solar photovoltaic panel, a control system, a display screen, a water inlet and a water outlet are arranged, a water pump is arranged in the box body, a first treatment cavity, a second treatment cavity, a third treatment cavity, a fourth treatment cavity and a water reservoir are also arranged in the box body, and the water inlet, the water pump, the first treatment cavity, the second treatment cavity, the third treatment cavity, the fourth treatment cavity, the water reservoir and the water outlet are connected through a pipeline;

[0007] The first processing cavity and the second processing cavity are separated by an inclined plate, and the inclined plate forms a slope in the first processing cavity, and an impurity groove is provided at the bottom of the slope;

[0008] The first treatment cavity is provided with a bioflocculant delivery device and can deliver bioflocculant into the first treatment cavity, the second treatment cavity is provided with an ozone micro-nano bubble generator, the third treatment cavity is provided with a microbial treatment layer and the microbial treatment layer includes immobilized microbial bacteria pellets, and the fourth treatment cavity is provided with an activated carbon adsorption layer;

[0009] The solar photovoltaic panel, the water pump, the bioflocculant delivery device, and the ozone micro-nano bubble generator are respectively connected to the control system.

[0010] Furthermore, a control valve is provided on the pipeline, and the control valve is connected to the control system.

[0011] Furthermore, the control system is provided with a display screen for displaying tailwater treatment information.

[0012] Furthermore, the preparation method of the bioflocculant is as follows:

[0013] The sterilized sludge supernatant is mixed with aquaculture wastewater at a ratio of 1: (6-11) to serve as a culture medium A, and then Rhodococcus erythropolis is inoculated into the culture medium A for activation and acclimation for 12h-48h to allow the Rhodococcus erythropolis to adapt to the culture medium environment and proliferate, and then the acclimated bacterial liquid is inoculated into a culture medium B at an inoculation amount of 1%-6% by volume, and fermented and cultured at a temperature of 30±2 for 18h-72h. After the fermentation is completed, the mixture is centrifuged, the supernatant is taken, and the bioflocculant is extracted with precooled ethanol, and the bioflocculant MBF-R is obtained after centrifugation, removal of the supernatant, and low-temperature drying.

[0014] Furthermore, the ozone micro-nano bubble generator can form micro-nano bubbles with a diameter of less than 50 μm, and the micro-nano bubbles are mixed with the treated tail water to form dissolved air micro-nano bubble water, and the dissolved air micro-nano bubble water returns to the ozone oxidation reactor through the drain port of the ozone micro-nano bubble generator. The rupture of ozone bubbles and ozone micro-nano bubbles can generate a large amount of hydroxyl radicals, and the hydroxyl radicals treat the organic matter in the treated tail water.

[0015] Furthermore, the immobilized microbial pellets include composite bacteria and a carrier for loading the bacteria, and the added amount of the composite bacteria accounts for 20% to 25% of the mass of the immobilized microbial pellets.

[0016] Furthermore, the carrier comprises the following raw materials in parts by weight: 10 to 25 parts of polyvinyl alcohol, 15 to 30 parts of sodium alginate, and 3 to 7 parts of calcium chloride.

[0017] Further, polyvinyl alcohol, sodium alginate and calcium chloride are added to the mixing kettle, stirred at 20°C to 30°C for 15min to 40min, and then microorganisms are added, and the stirring is continued for 10min to 20min to form immobilized microorganism pellets.

[0018] Furthermore, the composite bacteria is obtained by mixing Lactobacillus plantarum HYY-DB9, nitrifying bacteria, denitrifying bacteria and Bacillus in a mass ratio of (1-10): (1-3): (1-7): (1-9).

[0019] Furthermore, the thickness of the microbial treatment layer is 10 cm to 15 cm.

[0020] Compared with the prior art, this application has the following beneficial effects:

[0021] 1. The aquaculture tailwater treatment device of the present invention is optimized from the physical, chemical and biological perspectives, and adopts a combination of biological flocculants, ozone micro-nano bubble technology, immobilized microbial bacteria pellets and activated carbon. It has a significant effect on the removal of soluble pollutants, is not prone to secondary pollution such as solid waste and sludge, and has a high overall treatment efficiency.

[0022] 2. The optimized biological flocculant in this application is safe and non-toxic, and has good biodegradability and flocculation effect. Composite microorganisms are used for encapsulation and fixation, which has a synergistic effect and can improve the purification efficiency and stability. It has strong resistance to environmental factors and can be used for a long time. It also has obvious advantages in biological denitrification and can significantly improve the removal effect of ammonia nitrogen and COD.

[0023] 3. The composite aquaculture tailwater treatment device of the present invention has the advantages of overall safety and reliability, low cost, low energy consumption, and thorough treatment. Most importantly, it will not cause secondary pollution and has very good prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention can be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily drawn to scale, but the emphasis is placed on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0025] Figure 1 This is a schematic diagram of the overall structure of a composite aquaculture tailwater treatment device in Example 1 of the present invention;

[0026] Figure 2 This is a front view of a composite aquaculture tailwater treatment device in Example 1 of the present invention;

[0027] Figure 3 It is a top view of a composite aquaculture tailwater treatment device in Example 1 of the present invention;

[0028] Figure 4 It is a left view of a composite aquaculture tailwater treatment device in Example 1 of the present invention;

[0029] Figure 5 It is a right side view of a composite aquaculture tailwater treatment device in Example 1 of the present invention;

[0030] Figure 6 It is a rear view of a composite aquaculture tailwater treatment device in Example 1 of the present invention.

[0031] Description of reference numerals:

[0032] 1-Solar photovoltaic panel; 2-Control system; 3-Water pump; 4-Valve controllable return pipe;

[0033] 5-biological flocculant device; 6-impurity tank; 7-ozone micro-nano bubble generator; 8-immobilized microorganism layer; 9-activated carbon adsorption layer; 10-water reservoir; 11-slope; 12-water inlet; 13-display screen; 14-reflux pipe; 15-biological flocculant lowering device control line pipe; 16-impurity switch button; 17-ozone device operation control pipeline; 18-water outlet; 19-flocculant outlet; 20-filter; 21-mixing column; 22-first connecting pipe; 23-second connecting pipe; 24-biosensor; 25-third connecting pipe; 26-porous limiting layer drag plate. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with its embodiments. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0036] A composite aquaculture tailwater treatment device in one embodiment of the present invention comprises a box body, on which a solar photovoltaic panel 1, a control system 2, a display screen 14, a water inlet 12 and a water outlet 18 are arranged, a water pump 3 is arranged in the box body, and a first processing cavity, a second processing cavity, a third processing cavity, a fourth processing cavity and a water reservoir 10 are also arranged in the box body, and the water inlet 12, the water pump 3, the first processing cavity, the second processing cavity, the third processing cavity, the fourth processing cavity, the water reservoir 10 and the water outlet 18 are connected through a pipeline;

[0037] The first processing cavity and the second processing cavity are separated by an inclined plate, and the inclined plate forms a slope 11 in the first processing cavity, and an impurity groove 6 is provided at the bottom of the slope 11;

[0038] The first treatment cavity is provided with a bioflocculant delivery device 5 and can deliver bioflocculant into the first treatment cavity, the second treatment cavity is provided with an ozone micro-nano bubble generator 7, the third treatment cavity is provided with a microbial treatment layer 8 and the microbial treatment layer 8 includes immobilized microbial bacteria pellets, and the fourth treatment cavity is provided with an activated carbon adsorption layer 9;

[0039] The solar photovoltaic panel 1 , the water pump 3 , the bioflocculant delivery device 5 , and the ozone micro-nano bubble generator 7 are respectively connected to the control system 2 .

[0040] In one of the embodiments, the solar photovoltaic panel 1 provides power for the composite aquaculture tailwater treatment device, but the specific circuit connection is not limited in detail. It is sufficient to realize the operation of each part and will not be elaborated here.

[0041] In one embodiment, a control valve is provided on the pipeline, and the control valve is connected to the control system 2. It is used to control the opening of the control valve. It can then control the flow direction of aquaculture tailwater in the composite aquaculture tailwater treatment device. In one embodiment, the pipeline includes a first connecting pipe 22, a second connecting pipe 23 and a third connecting pipe 25, the first connecting pipe 22 connects the first processing cavity and the second processing cavity, the second connecting pipe 23 connects the second processing cavity and the third processing cavity, and the third connecting pipe 25 connects the third processing cavity and the water reservoir.

[0042] In one embodiment, a filter screen 20 is provided at the connection between the first connecting pipe 22 and the first processing cavity.

[0043] In one embodiment, the filter screen 20 is disposed at the bottom of the impurity tank 6. The impurity tank 6 is a push-pull type.

[0044] When the aquaculture tailwater enters the composite aquaculture tailwater treatment device of the present application from the water inlet 12 under the action of the water pump 3, the aquaculture tailwater will accumulate larger impurities in the impurity tank 6 under the action of the slope, and be intercepted by the filter screen; at the same time, the control system controls the biological flocculant delivery device 5 to deliver biological flocculants and target objects from the flocculant outlet 19. The target objects are organic matter, ammonia nitrogen, nitrite, phosphorus and other substances to achieve flocculation through interaction. This action is essentially the interaction between organic polymers and target objects. The mechanism of flocculation is mainly charge neutralization, bridging and sweeping. Under appropriate stirring and residence time, the biological flocculant is adsorbed on the surface of the suspended matter through physical or chemical action to promote its aggregation; then the floccules formed increase in density, and the large particles obtained by flocculation will not pass through the filter screen 20 due to precipitation. After accumulation in the impurity tank 6, the formed sediment can be removed by scraping mud, flushing and washing. The impurity tank 6 and the filter screen 20 are cleaned regularly when the machine is at rest to prevent clogging. Under the pressure of the filter screen 20 and the impurity tank 6, the aquaculture tail water with a large amount of impurities removed enters the second processing cavity through the first connecting pipe 23.

[0045] In one embodiment, the control system 2 is provided with a display screen 14 for displaying tailwater treatment information.

[0046] In one embodiment, the preparation method of the bioflocculant is as follows:

[0047] The sterilized sludge supernatant is mixed with aquaculture wastewater at a ratio of 1: (6-11) as culture medium A, and then Rhodococcus erythropolis is inoculated into the culture medium A for activation and acclimation for 12h-48h to adapt the Rhodococcus erythropolis to the culture medium environment and proliferate, and then the acclimated bacterial liquid is inoculated into the culture medium B at an inoculation rate of 1%-6% by volume, and fermented and cultured at a temperature of 30±2 for 18h-72h. After the fermentation is completed, centrifuge, take the supernatant and extract the bioflocculant with pre-cooled ethanol, and obtain the bioflocculant MBF-R after centrifugation, supernatant removal and low-temperature drying. The bioflocculant MBF-R prepared in the present application has excellent temperature-increasing degradability, is safe and non-toxic, is applied to the bioflocculant delivery device 5 and delivered, and has a significant flocculation effect.

[0048] In one embodiment, the concentration of the bioflocculant MBF-R is (0.5-10) g / L.

[0049] In one embodiment, the ozone micro-nano bubble generator 7 can form micro-nano bubbles with a diameter of less than 50 μm, and the micro-nano bubbles are mixed with the treated tail water to form dissolved air micro-nano bubble water, and the dissolved air micro-nano bubble water returns to the ozone oxidation reactor through the drain port of the ozone micro-nano bubble generator. The rupture of ozone bubbles and ozone micro-nano bubbles can produce a large amount of hydroxyl radicals, and the hydroxyl radicals treat the organic matter in the treated tail water.

[0050] In one embodiment, specifically, the ozone micro-nano bubble generator 7 includes a mixing column 21, and one end of the first connecting pipe 22 is connected to the first treatment cavity, the other end of the first connecting pipe 22 is connected to one end of the mixing column 21, and the other end of the mixing column 21 is connected to the ozone micro-nano bubble generator 7. The aquaculture tail water after flocculation treatment in the first treatment cavity enters the ozone micro-nano bubble generator 7 through the first connecting pipe 22 and the mixing column 21. The ozone micro-nano bubble generator 7 converts oxygen into ozone to form micro-nano bubbles with a diameter of less than 50 μm. The contact area and reaction rate of ozone and liquid can be significantly increased in the three mixing columns 21, so that the purification effect is better. At the same time, the micro-nano bubbles are fully in contact with pollutants such as organic matter and bacteria in the water, and then ozone degrades these pollutants through oxidation reaction. The specific process includes: ozone reacts with organic matter and decomposes into carbon dioxide and water; ozone can effectively kill bacteria and viruses in water and reduce biological pollution of water bodies. Microbubbles greatly improve the mass transfer and reaction rate of ozone oxidation, and the effective utilization rate of ozone is also significantly increased. The aquaculture wastewater treated by the ozone micro-nano bubble generator 7 enters the third treatment cavity through the second connecting pipe 23.

[0051] In one embodiment, the rate of the micro-nano ozone bubble technology is 40 mg / min.

[0052] In one embodiment, one end of the second connecting tube 23 is connected to the second processing cavity, and the other end of the second connecting tube 23 is connected to the third processing cavity.

[0053] In one embodiment, the immobilized microbial pellet comprises composite bacteria and a carrier for loading the bacteria, and the added amount of the composite bacteria accounts for 20% to 25% of the mass of the immobilized microbial pellet.

[0054] In one embodiment, the carrier comprises the following raw materials in parts by weight: 10 to 25 parts of polyvinyl alcohol, 15 to 30 parts of sodium alginate, and 3 to 7 parts of calcium chloride.

[0055] In one embodiment, polyvinyl alcohol, sodium alginate and calcium chloride are added to a mixing kettle, stirred at 20°C to 30°C for 15min to 40min, and then microorganisms are added, stirred for 10min to 20min, and formed to obtain immobilized microorganism pellets.

[0056] In one embodiment, the composite bacteria is obtained by mixing Lactobacillus plantarum HYY-DB9, nitrifying bacteria, denitrifying bacteria and Bacillus in a mass ratio of (1-10): (1-3): (1-7): (1-9).

[0057] In one embodiment, the plant lactobacillus HYY-DB9 is named Lactiplantibacillus plantarum HYY-DB9 (LP.DB9), which was deposited in Guangdong Provincial Microbiological Culture Collection Center on September 21, 2022, and the culture collection number is GDMCC 62815.

[0058] In one embodiment, the thickness of the microbial treatment layer is 10 cm to 15 cm.

[0059] In one of the embodiments, specifically, the third treatment cavity is also provided with an aquifer, a covering layer, a soil layer, a filler layer and a drainage layer from top to bottom, and the height of the aquifer is 10cm to 20cm, the height of the covering layer is 5cm to 10cm, the height of the soil layer is 15cm to 20cm, the height of the filler layer is 50cm to 60cm, and the height of the drainage layer is 15cm to 20cm.

[0060] In one embodiment, the covering layer is gravel with an average particle size of 10 mm to 15 mm.

[0061] In one embodiment, the soil layer is a mixture of clay and gravel.

[0062] In one embodiment, the packing layer is a layer of immobilized microorganism pellets and a layer of zeolite stacked in proportion, and the immobilized microorganism pellets account for 80% of the volume of the packing layer.

[0063] In one embodiment, a porous limiting support plate 26 is provided at the junction of the immobilized microbial ball layer and the zeolite layer. It can effectively avoid the extrusion deformation or even damage of the immobilized microbial ball layer by the material. When the aquaculture tail water enters the third treatment cavity, the treatment process includes: 1. Degradation of organic matter: microorganisms degrade organic pollutants in the water through metabolism. 2. Removal of nutrients: such as nitrogen, phosphorus and other nutrients, microorganisms can convert them into harmless substances. The bacteria in the immobilized microbial ball remove the organic pollutants, ammonia nitrogen, phosphorus and other pollutants remaining from the above treatment, and convert the pollutants into harmless substances through adsorption, degradation and other mechanisms, and protect the bacteria from environmental factors such as pH changes, temperature changes, etc. through immobilization technology, thereby improving the stability and activity of the bacteria. The immobilized bacteria have a fixed shape and size, which is convenient for separation and recovery in the wastewater treatment process, reducing the treatment cost. After passing through the third treatment cavity, it enters the fourth treatment cavity through the third connecting pipe 25.

[0064] In one embodiment, when the tail water of aquaculture enters the activated carbon adsorption layer, the porous structure of the activated carbon can adsorb pollutants in the water. The water treated by the activated carbon adsorption flows into the water reservoir 10 through the third connecting pipe 25 .

[0065] In one embodiment, a biosensor 24 is provided in the water reservoir 10, and the biosensor 24 is connected to the control system 2. The biosensor 24 detects whether the water in the water reservoir 10 is qualified. If qualified, it is discharged from the bottom outlet pipe 18 of the composite aquaculture treatment device to each aquaculture pond; if unqualified, it flows into the return pipe 14 through the controllable valve return pipe 4 at the bottom, and reflows under the action of the water pump 3 powered by the solar photovoltaic panel 1, enters from the water inlet 12, and is purified again, and the above process is repeated until the water in the water reservoir is detected to be qualified.

[0066] In one embodiment, the activated carbon is one or two of the following, as shown in Table 1.

[0067] Table 1: Types of activated carbon

[0068]

[0069]

[0070] In order to verify the effect of the composite aquaculture tailwater treatment device of the present application, the following experiments were conducted.

[0071] 1. Verification of the purification effect of bioflocculants

[0072] The aquaculture tailwater samples were divided into five groups, each with 100L, and different concentrations of bioflocculants were added. The samples were stirred for 30 minutes under fixed temperature and pH conditions to promote flocculation. After standing for 30 minutes, the supernatant was collected to determine the concentration of various indicators in each group, and the purification effect (removal rate) was calculated for analysis.

[0073] Experimental group: biological flocculant (Rhodococcus erythropolis flocculant) (concentration: 0.5g / L, 1g / L, 2g / L), traditional flocculant (such as polyaluminium chloride, concentration: 0.5g / L, 1g / L, 2g / L).

[0074] Control group: no additives.

[0075] Parameter settings: pH=7, flocculation time 20min, temperature 25°C, rotation speed 240r / min.

[0076] The results are shown in Table 2.

[0077] Table 2: Purification effect of bioflocculants

[0078]

[0079] From the data analysis of Table 2, it can be seen that the treatment effect of the biological flocculant of the present application is better than that of the traditional flocculant. It shows that biological flocculants show more superior effects in the purification of aquaculture wastewater, especially in the removal of total phosphorus and organic matter. Compared with traditional flocculants, biological flocculants can more effectively improve water quality and reduce pollutant concentrations. Traditional flocculants have played a positive role in water purification. However, the effect is not as good as that of biological flocculants. In addition, biological flocculants have significant advantages over ordinary flocculants, such as biodegradability, high efficiency, non-toxicity and no secondary pollution. Therefore, biological flocculants are better at tail water treatment than traditional flocculants.

[0080] 2. Verification of the purification effect of ozone micro-nano bubble technology

[0081] Aquaculture tail water samples were divided into four groups, with ozone dosage of 5738 mg / L, reaction time of 120 min, pH = 9. Before and after treatment, the concentrations of the above indicators were measured using appropriate instruments (such as spectrophotometer, COD meter, etc.). The results are shown in Table 3.

[0082] The specific groups are as follows:

[0083] Group 1: Micro-nano ozone bubble technology (low rate: 10mg / min)

[0084] Group 2: Micro-nano ozone bubble technology (medium rate: 20 mg / min)

[0085] Group 3: Micro-nano ozone bubble technology (high rate: up to 40mg / min)

[0086] Group 4: Traditional ozone technology

[0087] Table 3: Micro-nano bubble technology treatment results

[0088]

[0089]

[0090] It can be seen from Table 3 that the removal rate of ammonia nitrogen, total phosphorus, nitrite, suspended solids and COD by ozone micro-nano bubble technology is significantly higher than that of traditional ozone technology. This is due to the better solubility and reactivity of micro-nano bubbles, which greatly increases the contact time and area between ozone and pollutants.

[0091] 3. Verification of the purification effect of immobilized microorganisms

[0092] The experiment set up 6 groups, namely:

[0093] Experimental group 1: immobilized Lactobacillus plantarum HYY-DB9;

[0094] Experimental group 2: immobilized nitrifying bacteria;

[0095] Experimental group 3: immobilized denitrifying bacteria;

[0096] Experimental group 4: fixed Bacillus;

[0097] Experimental group 5: composite bacteria (Lactobacillus plantarum HYY-DB9, nitrifying bacteria, denitrifying bacteria, and Bacillus in a mass ratio of 10:3:5:7);

[0098] Control group: traditional fixed microorganisms;

[0099] The microorganisms in the above test group were fixed by the following preparation method: 25 parts of polyvinyl alcohol, 18 parts of sodium alginate and 5 parts of calcium chloride were added to a mixing kettle, stirred at 30°C for 35 minutes, and then the corresponding microorganisms were added, and the stirring was continued for 20 minutes to form immobilized microorganism pellets.

[0100] Three replicates were set for each group to improve the reliability of the experiment. The results are shown in Table 4 below.

[0101] Table 4: Microbial purification effect

[0102]

[0103]

[0104] From the data analysis in Table 4, it can be seen that after the combined use of microorganisms, there is a significant removal effect on nitrite, ammonia nitrogen, total phosphorus and suspended solids, among which Lactobacillus plantarum HYY-DB9 is better than other strains.

[0105] 4. Comprehensive purification effect verification

[0106] Treating aquaculture tail water through a composite aquaculture tail water treatment device;

[0107] The setting conditions are as follows:

[0108] Bioflocculant (Rhodococcus erythropolis) release rate: 2g / L, i.e. 2kg / h;

[0109] Ozone micro-nano bubble generation rate: 40 mg / min, ozone dosage 5738 mg / L, reaction time 120 min, pH = 9;

[0110] Types of immobilized microorganisms: Lactobacillus plantarum HYY-DB9, nitrifying bacteria, denitrifying bacteria, and Bacillus in a mass ratio of 10:3:5:7;

[0111] Biological activated carbon: wood columnar activated carbon;

[0112] The water in the last water reservoir 10 was detected and the purification effect was calculated. The results showed that the ammonia nitrogen removal rate was 93.88%, the total phosphorus removal rate was 91.12%, the nitrite removal rate was 96.60%, the suspended solids removal rate was 98.72%, and the COD removal rate was 93.80%. It is explained that the composite aquaculture tailwater treatment device of the present application has the advantages of high treatment efficiency, fast reaction, less microbial loss, and stable and reliable operation after optimization. It also solves the problems of low mass transfer efficiency and oxidation efficiency of ozone under the traditional aeration mode of ozone, high operating cost, and the selective oxidation of ozone to organic matter and the inability to oxidize and decompose some difficult-to-degrade organic matter. Combining micro-nano technology with ozone, ozone combined with micro-nano bubbles can stimulate the generation of a large number of hydroxyl free radicals, which can effectively enhance the oxidation capacity of ozone and strengthen the removal effect of ozone on difficult-to-degrade organic pollutants; and it also has the advantages of no secondary pollution, low operating cost, simple operation and management, etc., which improves the further promotion and application of ozone technology in the field of water treatment and has broad application prospects in the field of water treatment. Specifically, the present invention selects the best process after the purification effect verification experiment of the biological flocculant (Rhodococcus erythropolis), the purification effect verification experiment of the ozone micro-nano bubble technology and the purification effect verification experiment of the microbial fixed bacteria: the concentration of the biological flocculant (Rhodococcus erythropolis) is 2g / l, the ozone micro-nano bubble rate is 40mg / min, the composite microbial fixed flora (Lactobacillus plantarum HYY-DB9, nitrifying bacteria, denitrifying bacteria, Bacillus) and biological activated carbon (wood columnar activated carbon), and the comprehensive purification effect verification experiment is carried out under the setting of fixed temperature, pH and reaction time. (The process conditions used in this experiment are applicable to the test aquaculture tail water, and the actual process conditions can be changed according to the actual situation) The experimental results show that the device has excellent total removal rates for ammonia nitrogen, total phosphorus, nitrite, suspended matter and COD, and achieves a good purification effect as a whole.

[0113] 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.

[0114] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A composite aquaculture tailwater treatment device, comprising a box body, on which a solar photovoltaic panel, a control system, a display screen, a water inlet and a water outlet are arranged, and a water pump is arranged in the box body, characterized in that: The box body is also provided with a first processing cavity, a second processing cavity, a third processing cavity, a fourth processing cavity and a water reservoir, and the water inlet, the water pump, the first processing cavity, the second processing cavity, the third processing cavity, the fourth processing cavity, the water reservoir and the water outlet are connected through a pipeline; The first processing cavity and the second processing cavity are separated by an inclined plate, and the inclined plate forms a slope in the first processing cavity, and an impurity groove is provided at the bottom of the slope; The first treatment cavity is provided with a bioflocculant delivery device and can deliver bioflocculant into the first treatment cavity, the second treatment cavity is provided with an ozone micro-nano bubble generator, the third treatment cavity is provided with a microbial treatment layer and the microbial treatment layer includes immobilized microbial bacteria pellets, and the fourth treatment cavity is provided with an activated carbon adsorption layer; The solar photovoltaic panel, the water pump, the bioflocculant delivery device, and the ozone micro-nano bubble generator are respectively connected to the control system.

2. The composite aquaculture tailwater treatment device according to claim 1, characterized in that: A control valve is arranged on the pipeline, and the control valve is connected to the control system.

3. According to the composite aquaculture tailwater treatment device of claim 1, the control system is provided with a display screen for displaying tailwater treatment information.

4. The composite aquaculture tailwater treatment device according to claim 1, characterized in that: The preparation method of the bioflocculant is as follows: The sterilized sludge supernatant is mixed with aquaculture wastewater at a ratio of 1: (6-11) to serve as a culture medium A, and then Rhodococcus erythropolis is inoculated into the culture medium A for activation and acclimation for 12h-48h to allow the Rhodococcus erythropolis to adapt to the culture medium environment and proliferate, and then the acclimated bacterial liquid is inoculated into a culture medium B at an inoculation amount of 1%-6% by volume, and fermented and cultured at a temperature of 30±2 for 18h-72h. After the fermentation is completed, the mixture is centrifuged, the supernatant is taken, and the bioflocculant is extracted with precooled ethanol, and the bioflocculant MBF-R is obtained after centrifugation, removal of the supernatant, and low-temperature drying.

5. The composite aquaculture tailwater treatment device according to claim 1, characterized in that: The ozone micro-nano bubble generator can form micro-nano bubbles with a diameter of less than 50 μm, and the micro-nano bubbles are mixed with the treated tail water to form dissolved air micro-nano bubble water, and the dissolved air micro-nano bubble water returns to the ozone oxidation reactor through the drain port of the ozone micro-nano bubble generator. The ozone bubbles and the ozone micro-nano bubbles burst to generate a large amount of hydroxyl free radicals, and the hydroxyl free radicals treat the organic matter in the treated tail water.

6. The composite aquaculture tailwater treatment device according to claim 1, characterized in that: The immobilized microorganism pellet comprises composite bacteria and a carrier for loading the bacteria, and the added amount of the composite bacteria accounts for 20% to 25% of the mass of the immobilized microorganism pellet.

7. The composite aquaculture tailwater treatment device according to claim 5, characterized in that: The carrier comprises the following raw materials in parts by weight: 10 to 25 parts of polyvinyl alcohol, 15 to 30 parts of sodium alginate, and 3 to 7 parts of calcium chloride.

8. The composite aquaculture tailwater treatment device according to claim 6, characterized in that: Add polyvinyl alcohol, sodium alginate and calcium chloride into a mixing kettle, stir for 15 to 40 minutes at 20 to 30 degrees Celsius, then add microorganisms, continue stirring for 10 to 20 minutes, and form to obtain immobilized microorganism pellets.

9. The composite aquaculture tailwater treatment device according to claim 7, characterized in that: The composite bacteria is obtained by mixing plant lactobacillus HYY-DB9, nitrifying bacteria, denitrifying bacteria and bacillus in a mass ratio of (1-10): (1-3): (1-7): (1-9).

10. The composite aquaculture tailwater treatment device according to claim 9, characterized in that: The thickness of the microbial treatment layer is 10 cm to 15 cm.

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