Combined ecological floating bed and application thereof

Abstract

The invention provides a combined ecological floating bed and application thereof, the ecological floating bed mainly comprises a floating body and a biological load layer, and the floating body enables the combined ecological floating bed to float on the surface of a water body and provides a growth space for the biological load layer; the biological load layer comprises sea horse teeth and immobilized small balls, the immobilized small balls comprise bacterium immobilized small balls and / or bacterium-alga immobilized small balls, the raw materials of the bacterium immobilized small balls comprise salinity domestication activated sludge and sodium alginate, and the raw materials of the bacterium-alga immobilized small balls comprise salinity domestication activated sludge, chlorella and sodium alginate. The combined ecological floating bed has excellent biological stability and environmental stability, the removal efficiency of NH4 < + >-N, TP and TN is improved, comprehensive removal of multiple nutritive salts is achieved, the treatment effect of the aquaculture tail water is remarkably improved, meanwhile, the problem that a traditional floating bed is insufficient in stability in the aquaculture tail water environment is effectively solved, and the combined ecological floating bed has good application prospects. And the defect that the floating bed device is easy to incline or sink in the prior art is overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of seawater aquaculture, and in particular to a combined ecological floating bed and applications thereof. Background Art

[0002] With the rapid development of marine aquaculture, the treatment of aquaculture wastewater has become an increasingly prominent issue. Large amounts of aquaculture wastewater contain high concentrations of pollutants such as nutrients, organic matter, and trace elements. If discharged directly without treatment, it will cause serious harm to aquatic life and the surrounding aquatic environment. Currently, commonly used aquaculture wastewater treatment technologies include physical, chemical, and biological treatment. However, these traditional treatment methods have problems such as high investment costs, high energy consumption, unstable treatment results, and the tendency to cause secondary pollution.

[0003] As an emerging water purification technology, ecological floating bed technology has been widely used in water quality improvement and ecological environment restoration due to its advantages such as low cost, environmental protection, and easy control of secondary pollution. In order to solve the problem of nutrient removal in marine aquaculture tail water, there are currently some inventions that use ecological floating bed technology, such as patent documents CN102030416 and CN105859045A. However, the single ecological floating bed technology still has some limitations, such as the lack of coupling effect between plant roots and biological fillers, the lack of strengthening of microorganisms in the ecosystem, and the serious damage to the bed structure. Moreover, when treating marine aquaculture tail water, the removal effect of nutrients is limited, and it is difficult to achieve efficient removal and recovery of nutrients such as nitrogen and phosphorus in the water body. In addition, the application of traditional floating bed structures in aquaculture tail water environments also faces challenges such as the floating bed device being easy to tilt or sink, and the poor attachment effect of plant roots. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a combined ecological floating bed and its application, which has excellent biological stability and environmental stability, improves the resistance to NH4 + -N, TP and TN removal efficiency, realizes the comprehensive removal of multiple nutrients, and significantly improves the treatment effect of aquaculture tail water.

[0005] The specific technical solutions of the present invention are: In a first aspect, the present invention provides a combined ecological floating bed, which includes a float and a bioburden layer. The float enables the combined ecological floating bed to float on the surface of the water body and provides growth space for the bioburden layer; the bioburden layer includes seahorse teeth and immobilized balls, and the immobilized balls include bacteria immobilized balls and / or bacteria and algae immobilized balls. The raw materials of the bacteria immobilized balls include salinity-acclimated activated sludge and sodium alginate, and the raw materials of the bacteria and algae immobilized balls include salinity-acclimated activated sludge, chlorella and sodium alginate.

[0006] Furthermore, the float is composed of a PVC tube, a float plate and several bait cages. The PVC tube surrounds the float plate, and the float plate is provided with multiple aquatic plant fixing holes. When in use, the PVC tube and the float plate are fixed on the upper surface of the fishing net, and several bait cages are fixed on the corresponding lower surfaces of the fishing net; the seahorse teeth are placed in the aquatic plant fixing holes, and the immobilized balls are placed in the bait cages.

[0007] Furthermore, the immobilization beads are prepared by the following method: S1, mixing salinity-acclimated activated sludge concentrate with sodium alginate solution, or mixing salinity-acclimated activated sludge concentrate, Chlorella and sodium alginate solution to form a mixed solution; the concentration of the sodium alginate solution is 20-30 g / L, the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution in the mixed solution is 1:(2-20), and the concentration of the Chlorella in the mixed solution is 30-50 g / L; S2. Dropping the mixed solution in step S1 into a solution containing CaCl2 and BaCl2, wherein the mass percentage of CaCl2 in the solution is 1%-5% and the mass percentage of BaCl2 is 1-5%, stirring and mixing evenly, and then cross-linking and curing at a temperature of 0-10°C to obtain immobilized beads.

[0008] Furthermore, the salinity-acclimated activated sludge concentrate in step S1 is prepared by the following method: D1. Prepare a culture medium: dissolve NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in artificial seawater to form a mixture, and add a nutrient solution to the mixture to prepare a salinity-acclimated culture medium; the concentrations of NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in the mixture are 45-50 mg / L, 10-15 mg / L, 300-350 mg / L, 20-25 mg / L, and 1-3 mg / L, respectively; D2. Salinity acclimation: Activated sludge is placed in an SBR reactor filled with the culture solution described in step D1, wherein the activated sludge has a 30-min sludge settling ratio (SV30) of 40-50%, a concentration of 7000-7100 mg / L, and a non-volatile suspended solids concentration of 3400-3600 mg / L. An intermittent acclimation method is used for multiple acclimation cycles, each of which includes water intake, anoxic conditions, culture, and drainage processes. The influent salinity gradually increases during the multiple acclimation cycles, and the influent salinity is 1-25 ppt. After the acclimation is completed, a salinity-acclimated activated sludge concentrate is obtained.

[0009] Furthermore, the solvent of the sodium alginate solution is water, the concentration of the sodium alginate solution is 20 g / L, and the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution is 1:10.

[0010] Furthermore, the cross-linking and curing in step S2 is carried out at a temperature of 0-4°C and for a time of ≥20 h.

[0011] In the second aspect, the present invention also provides an application of the above-mentioned combined ecological floating bed in the ecological restoration of seawater aquaculture water bodies, comprising the following steps: placing the float of the above-mentioned combined ecological floating bed in a reactor, adding aquaculture tail water into the reactor, adding the seahorse teeth and the immobilized balls into the float to perform aquaculture tail water restoration.

[0012] Furthermore, the mass-to-volume ratio of the immobilized beads to the aquaculture tail water is 1:(5-25) g / mL.

[0013] Furthermore, the immobilized beads are recycled after strengthening, and the strengthening process is to place the immobilized beads in a solution containing CaCl2 and BaCl2 for fixation, wherein the mass percentage of CaCl2 in the solution is 1%-5%, and the mass percentage of BaCl2 is 1%-5%.

[0014] Furthermore, the hydraulic retention time of the aquaculture tail water in the reactor is 8-96 h.

[0015] The positive progress effect of the present invention is: The combined ecological floating bed provided by the present invention adopts seahorse teeth and bacteria immobilization balls or bacteria and algae immobilization balls as the biological load layer. The bacteria and / or bacteria and algae immobilization balls can effectively fix and stabilize the microorganisms in the activated sludge, thereby improving the biological stability and durability of the combined ecological floating bed; through the mutual cooperation of seahorse teeth and bacteria and / or bacteria and algae immobilization balls, the combined ecological floating bed effectively improves the NH4 + -N, TP and TN removal efficiency is improved, and the comprehensive removal of multiple nutrients is achieved, which significantly improves the treatment effect of aquaculture tail water; and because bacteria immobilization balls and / or bacteria and algae immobilization balls are added to the combined ecological floating bed, the density of the combined ecological floating bed can be made close to the density of aquaculture tail water, which effectively solves the problem of insufficient stability of traditional floating beds in aquaculture tail water and overcomes the shortcomings of floating bed devices in the existing technology that are easy to tilt or sink. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 NH4 in the water samples of Examples 1-9 and Comparative Examples 1-3 + -N removal rate change data chart.

[0017] Figure 2 1-3 and 1-9, respectively.

[0018] Figure 3 TP removal rate change data chart for the water samples of Examples 1-9 and Comparative Examples 1-3.

[0019] Figure 4 NH4 in the water samples of Comparative Example 4, Comparative Example 5, Example 10 and Example 11 + -N removal rate change data chart.

[0020] Figure 5 This is a data graph of the change in TN removal rate in the water samples of Comparative Example 4, Comparative Example 5, Example 10 and Example 11.

[0021] Figure 6 TP removal rate change data graph for the water samples of Comparative Example 4, Comparative Example 5, Example 10 and Example 11.

[0022] Figure 7 NH4 in the water samples of Example 1 and Example 13 + -N removal rate change data chart.

[0023] Figure 8 1 and 13 are data graphs showing changes in TN removal rates in the water samples of Example 1 and Example 13.

[0024] Figure 9 1 is a graph showing the change in TP removal rate in the water samples of Example 1 and Example 13.

[0025] Figure 10 NH4 in the water samples of Examples 1, 12, 13 and 14 + -N removal rate change data chart.

[0026] Figure 11 This is a data graph of the change in TN removal rate in the water samples in Example 1, Example 12, Example 13 and Example 14.

[0027] Figure 12 This is a data graph of the change in TP removal rate in the water samples in Example 1, Example 12, Example 13 and Example 14.

[0028] Figure 13 NH4 in the water samples of Example 15, Example 16, and Comparative Examples 6-9 + -N removal rate change data chart.

[0029] Figure 14 This is a data graph showing the change in TN removal rate in the water samples of Example 15, Example 16, and Comparative Examples 6-9.

[0030] Figure 15 This is a data graph showing the change in TP removal rate in the water samples of Example 15, Example 16, and Comparative Examples 6-9.

[0031] Figure 16 Schematic diagram of the three-dimensional structure of the combined ecological floating bed in the embodiment.

[0032] Description of Reference Numerals 1-PVC pipe, 2-floating bed, 3-bait cage, 4-fishing net, 5-seahorse teeth, 6-fixing hole for aquatic plants. DETAILED DESCRIPTION

[0033] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only intended to illustrate the implementation methods and typical parameters of the present invention, and are not intended to limit the parameter ranges described in the present invention. Reasonable variations derived therefrom are still within the scope of protection of the claims of the present invention.

[0034] It should be noted that the endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.

[0035] Unless otherwise defined, all terms, symbols and other scientific terms used herein are intended to have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. In some cases, terms with conventional meanings are defined herein for the purpose of clarification or ease of reference, and such definitions herein should not be construed as indicating significant differences from conventional understandings in the art. The technical methods described or cited herein are generally well understood by those skilled in the art and are adopted by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents and instruments was carried out in accordance with the protocols and parameters given by the manufacturers.

[0036] The specific technical solutions of the present invention are: In a first aspect, the present invention provides a combined ecological floating bed, which includes a float and a bioburden layer. The float enables the combined ecological floating bed to float on the surface of the water body and provides growth space for the bioburden layer. The bioburden layer includes seahorse teeth and immobilized balls. The immobilized balls include bacteria immobilized balls and / or bacteria and algae immobilized balls. The raw materials of the bacteria immobilized balls include salinity-acclimated activated sludge and sodium alginate. The raw materials of the bacteria and algae immobilized balls include salinity-acclimated activated sludge, chlorella and sodium alginate.

[0037] The combined ecological floating bed provided by the present invention adopts seahorse teeth and bacteria-immobilized balls or bacteria-algae-immobilized balls as biological load layers. The bacteria-immobilized balls and / or bacteria-algae-immobilized balls can effectively fix and stabilize the microorganisms in the activated sludge, thereby improving the biological stability and durability of the combined ecological floating bed; through the mutual cooperation between the seahorse teeth and the bacteria-immobilized balls and / or bacteria-algae-immobilized balls, the seahorse teeth can release oxygen required by the microorganisms in the immobilized balls through photosynthesis, and the microbial community in the salinity-acclimated activated sludge in the bacteria-immobilized balls or bacteria-algae-immobilized balls has adapted to the high-salt environment and can maintain high activity during use; the carboxyl and hydroxyl functional groups of sodium alginate can chelate heavy metals. When the immobilized balls contain chlorella, the chlorella can not only provide oxygen through photosynthesis, but also consume the CO2 produced by bacterial decomposition, and the cell wall polysaccharides of the chlorella can specifically adsorb phosphate, forming a physical-chemical-biological triple purification mechanism, which effectively improves the combined ecological floating bed's NH4 + -N, TP and TN removal efficiency is improved, and the comprehensive removal of multiple nutrients is achieved, which significantly improves the treatment effect of aquaculture tail water; and because bacteria immobilization balls and / or bacteria and algae immobilization balls are added to the combined ecological floating bed, the density of the combined ecological floating bed can be made close to the density of aquaculture tail water, which effectively solves the problem of insufficient stability of traditional floating beds in aquaculture tail water and overcomes the shortcomings of floating bed devices in the existing technology that are easy to tilt or sink.

[0038] The float consists of a PVC tube 1, a floating plate 2, and several bait cages 3. The PVC tube 1 surrounds the floating plate 2, which is provided with multiple aquatic plant fixing holes 6. During use, the PVC tube 1 and floating plate 2 are fixed to the upper surface of a fishing net 4, while the bait cages 3 are fixed to the corresponding lower surfaces of the fishing net 4. Seahorse teeth 5 are placed in the aquatic plant fixing holes 6, and immobilized pellets are placed in the bait cages 3. The PVC tube and floating plate provide sufficient buoyancy, and the porous walls of the bait cages allow water to flow through, improving the material exchange rate.

[0039] Furthermore, the immobilized beads are prepared by the following method: S1. Mixing salinity-acclimated activated sludge concentrate with a sodium alginate solution, or mixing salinity-acclimated activated sludge concentrate, Chlorella vulgaris, and a sodium alginate solution to form a mixed solution; the concentration of the sodium alginate solution is 20-30 g / L, and the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution in the mixed solution is 1:(2-20); when the mixed solution contains Chlorella vulgaris, the concentration of the Chlorella vulgaris in the mixed solution is 30-50 g / L; S2. Dropping the mixed solution in step S1 into a solution containing CaCl2 and BaCl2, wherein the mass percentage of CaCl2 in the solution is 1%-5% and the mass percentage of BaCl2 is 1-5%, stirring and mixing evenly, and then cross-linking and curing at a temperature of 0-10°C to obtain immobilized beads.

[0040] The above-mentioned preparation method of the immobilized beads is conducive to forming a three-dimensional network structure with an appropriate pore size in the immobilized beads by controlling the concentration of the sodium alginate solution, which not only guarantees the mass transfer requirements inside the immobilized beads, but also ensures that the immobilized beads have sufficient mechanical strength; by controlling the volume ratio of the salinity-acclimated activated sludge and the sodium alginate solution, the immobilized beads can be adapted to aquaculture tail waters with different pollution levels. When the aquaculture tail water is highly polluted, the use of a high-proportion salinity-acclimated activated sludge can increase the density of microorganisms. When the aquaculture tail water is low-pollution, the use of a low-proportion salinity-acclimated activated sludge can reduce competition among microorganisms and extend the service life of the immobilized beads; by controlling the concentration of Chlorella in the mixed solution, it is conducive to maintaining the dynamic balance of bacteria and algae in the immobilized beads; Ca in CaCl2 + ions combine with sodium alginate to form a primary gel network, and the Ba in BaCl2 + The ionic radius of the ions is larger, and cross-linking with sodium alginate can enhance the density of the gel grid and improve the mechanical strength of the immobilized beads; low-temperature cross-curing can improve the survival rate of bacteria and algae and form a uniform pore size distribution inside the immobilized beads; using the above-mentioned method for preparing immobilized beads, bacteria immobilized beads with moderate pore size, uniform pore size distribution, high survival rate of bacteria and algae and high mechanical strength can be prepared.

[0041] Furthermore, the salinity-acclimated activated sludge concentrate in step S1 is prepared by the following method: D1. Prepare culture medium: Dissolve NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in artificial seawater to form a mixture, and add nutrient solution to the mixture to prepare salinity-acclimated culture medium; the concentrations of NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in the mixture are 45-50 mg / L, 10-15 mg / L, 300-350 mg / L, 20-25 mg / L, and 1-3 mg / L, respectively; D2. Salinity acclimation: The activated sludge is placed in an SBR reactor filled with the culture medium in step D1, the 30-min sludge settling ratio SV30 of the activated sludge is 40-50%, the concentration is 7000-7100 mg / L, and the non-volatile suspended solids concentration is 3400-3600 mg / L. An intermittent acclimation method is used for multiple acclimation cycles, each acclimation cycle includes water inlet, anoxic, culture and drainage processes, and the inlet salinity gradually increases during the multiple acclimation cycles, and the inlet salinity is 1-25 ppt. After the acclimation, a salinity-acclimated activated sludge concentrate is obtained.

[0042] By adopting the above-mentioned salinity acclimation method of activated sludge, salt-tolerant microbial communities in the activated sludge can be selected, and the salt tolerance of the microbial communities can be further improved through a periodic gradient salinity acclimation scheme, thereby obtaining a salinity-acclimated activated sludge concentrate containing a highly salt-tolerant microbial community.

[0043] Furthermore, the solvent of the sodium alginate solution is water, the concentration of the sodium alginate solution is 20 g / L, and the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution is 1:10. By further optimizing the concentration of the sodium alginate solution and controlling the ratio of the salinity-acclimated activated sludge to the sodium alginate solution, the NH4 + -N, TP and TN removal efficiency.

[0044] Furthermore, the crosslinking and curing temperature in step S2 is 0-4°C and the time is ≥20 hours. Using a lower temperature and a longer time for slow crosslinking and curing can further improve the survival rate of bacteria and algae and the uniformity of the pore size distribution within the immobilized beads.

[0045] In the second aspect, the present invention also provides an application of the above-mentioned combined ecological floating bed in the ecological restoration of seawater aquaculture water bodies, comprising the following steps: placing the float of the above-mentioned combined ecological floating bed in a reactor, adding aquaculture tail water into the reactor, adding seahorse teeth and immobilized balls into the float to repair the aquaculture tail water.

[0046] Furthermore, the mass volume ratio of the immobilized beads to the aquaculture tail water is 1:(5-25) g / mL. By controlling the mass volume ratio of the immobilized beads to the aquaculture tail water within an appropriate range, it is beneficial to improve the NH4 + -N, TP and TN removal efficiency.

[0047] Furthermore, the immobilized beads are reinforced for recycling. The reinforcement process involves immobilizing the beads in a solution containing CaCl2 and BaCl2, where the mass percentage of CaCl2 is 1%-5% and the mass percentage of BaCl2 is 1%-5%. This further reinforcement can increase the strength of the immobilized beads and their service life during recycling.

[0048] Furthermore, the hydraulic retention time of the aquaculture tail water in the reactor is 8-96 h.

[0049] The technical solutions of the present invention are further illustrated below with reference to specific examples and comparative examples. All reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment. The instruments used in the examples are commercially available.

[0050] Example 1 This embodiment provides a combined ecological floating bed, such as Figure 16 As shown, it includes a float and a bioburden layer. The float consists of a PVC tube 1, a floating plate 2 and 28 bait cages 3. The floating plate 2 is formed in a rectangular shape. The PVC tube 1 is surrounded by the floating plate 2. The floating plate 2 is provided with 35 aquatic plant fixing holes 6. When in use, the PVC tube 1 and the floating plate 2 are fixed to the upper surface of the fishing net 4, and the 28 bait cages 3 are fixed to the lower surface of the fishing net 4; the bioburden layer includes seahorse teeth 5 and bacteria immobilization pellets. The seahorse teeth 5 are placed in the aquatic plant fixing holes 6, and the bacteria immobilization pellets are placed in the bait cages 3.

[0051] The method for preparing bacteria-immobilized pellets in the combined ecological floating bed of this embodiment comprises the following steps: S1, 9 mL of salinity-acclimated activated sludge concentrate and 91 mL of 22 g / L sodium alginate aqueous solution were mixed evenly to form a mixed solution; S2. Use a 10 mL PP burette to drop the mixed solution in step D1 into a pre-cooled 2% CaCl2 and 2% BaCl2 solution. After stirring for a certain time of 1 hour, place it in a 0-4 ° C refrigerator to solidify and cross-link for 24 hours, and then rinse with distilled water to obtain a certain number of bacteria-immobilized beads.

[0052] The method for preparing salinity-acclimated activated sludge concentrate in this embodiment comprises the following steps: D1. Prepare culture medium: Dissolve 47.8 mg NH4Cl, 11 mg KH2PO4, 320 mg NaOAc, 20 mg MgSO4·7H2O, and 10 mg CaCl2 in 1 L artificial seawater. Add 1 mL of nutrient solution to prepare salinity-acclimated culture medium. The salinity is adjusted as the experiment progresses. The nutrient solution contains 1500 mg / L FeCl3·6H2O, 150 mg / L H3BO3, 30 mg / L CuSO4·5H2O, 180 mg / L KI, 120 mg / L MnCl2·4H2O, 60 mg / L Na2MoO4·2H2O, 120 mg / L ZnSO4·7H2O, and 150 mg / L CoCl2·6H2O. D2. Salinity acclimation: The activated sludge was placed in an SBR reactor filled with the culture medium in step D1, the 30-min sludge settling ratio SV30 of the activated sludge was 46%, the concentration was 7050 mg / L, and the non-volatile suspended solids concentration was 3500 mg / L. An intermittent acclimation method was used for 28 acclimation cycles, with one cycle running per day. The duration of each cycle was 12 hours. The acclimation cycle included 15 minutes of water inflow, 3.5 hours of anoxic conditions, 1.5 hours of good culture, and 15 minutes of drainage. The anoxic conditions and good culture conditions were alternated twice each. At the same time, the aeration rate of the SBR reactor was controlled at 0.5 L / h, and the sedimentation time was controlled at 1.5 hours. The influent salinity in the 1st to 4th acclimation cycles was 1 ppt, the influent salinity in the 5th to 8th acclimation cycles was 2 ppt, the influent salinity in the 9th to 12th acclimation cycles was 5 ppt, and the influent salinity in the 13th to 16th acclimation cycles was 10 ppt. ppt, the influent salinity was 15 ppt in the 17th-20th acclimation cycle, 20 ppt in the 20th-24th acclimation cycle, and controlled at 25 ppt in the 24th-28th cycle. After the acclimation, the salinity-acclimated activated sludge concentrate was obtained.

[0053] The immobilized bacteria pellets in this example were used for ecological restoration of marine aquaculture water bodies. 400 mL of artificial aquaculture tail water was added to a suction flask, and 20 g of the immobilized bacteria pellets were evenly added to the suction flask. A peristaltic pump was used to continuously and quantitatively feed water into the suction flask. The temperature in the suction flask was controlled at 20-30°C and HRT = 24 h. The incubation time was 8 days, and each cycle was 2 days. The temperature in the suction flask was controlled at 20-30°C and HRT = 24 h. Samples were taken every 1 or 2 days for analysis to determine the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:10, 1:20.

[0054] The combined ecological floating bed in this embodiment was used for ecological restoration of marine aquaculture water bodies. The combined ecological floating bed was placed in a reactor. 80 L of artificial aquaculture tail water was added to the reactor. 4 kg of bacterial immobilization pellets were evenly placed in 28 bait cages. A peristaltic pump was used to achieve continuous quantitative water inflow and outflow in the reactor. The temperature in the reactor was controlled at 20-30°C, the hydraulic retention time HRT was 24 h, each cycle was 2 days, and samples were taken every 2 days for analysis. The incubation time was 16 days, and the NH4 + -N, TP and TN contents, the corresponding data results are marked with Example 1.

[0055] Example 2

[0056] The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 200 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:10, 1:10.

[0057] Example 3

[0058] The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 1000 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:10, 1:50.

[0059] Example 4

[0060] This embodiment provides a combined ecological floating bed, such as Figure 16 As shown, it includes a float and a bioburden layer. The float consists of a PVC tube 1, a floating plate 2 and 28 bait cages 3. The floating plate 2 is formed in a rectangular shape. The PVC tube 1 is surrounded by the floating plate 2. The floating plate 2 is provided with 35 aquatic plant fixing holes 6. When in use, the PVC tube 1 and the floating plate 2 are fixed to the upper surface of the fishing net 4, and the 28 bait cages 3 are fixed to the lower surface of the fishing net 4; the bioburden layer includes seahorse teeth 5 and bacteria immobilization pellets. The seahorse teeth are placed in the aquatic plant fixing holes, and the bacteria immobilization pellets are placed in the bait cages 3.

[0061] The method for preparing bacteria-immobilized pellets in the combined ecological floating bed of this embodiment comprises the following steps: S1, 17 mL of salinity-acclimated activated sludge concentrate and 83 mL of 24 g / L sodium alginate aqueous solution were mixed evenly to form a mixed solution; S2. Use a 10 mL PP burette to drop the mixed solution in step D1 into a pre-cooled 2% CaCl2 and 2% BaCl2 solution. After stirring for a certain time of 2 hours, place it in a 0-4 ° C refrigerator to solidify and cross-link for 24 hours, and then rinse with distilled water to obtain a certain number of bacteria-immobilized beads.

[0062] The method for preparing salinity-acclimated activated sludge concentrate in this embodiment comprises the following steps: D1. Prepare culture medium: Dissolve 47.8 mg NH4Cl, 11 mg KH2PO4, 320 mg NaOAc, 20 mg MgSO4·7H2O, and 10 mg CaCl2 in 1 L artificial seawater. Add 1 mL of nutrient solution to prepare salinity-acclimated culture medium. The salinity is adjusted as the experiment progresses. The nutrient solution contains 1500 mg / L FeCl3·6H2O, 150 mg / L H3BO3, 30 mg / L CuSO4·5H2O, 180 mg / L KI, 120 mg / L MnCl2·4H2O, 60 mg / L Na2MoO4·2H2O, 120 mg / L ZnSO4·7H2O, and 150 mg / L CoCl2·6H2O. D2. Salinity acclimation: The activated sludge was placed in an SBR reactor filled with the culture medium in step D1, the 30-min sludge settling ratio SV30 of the activated sludge was 46%, the concentration was 7050 mg / L, and the non-volatile suspended solids concentration was 3500 mg / L. An intermittent acclimation method was used for 28 acclimation cycles, with one cycle running per day. The duration of each cycle was 12 hours. The acclimation cycle included 15 minutes of water inflow, 3.5 hours of anoxic conditions, 1.5 hours of good culture, and 15 minutes of drainage. The anoxic conditions and good culture conditions were alternated twice each. At the same time, the aeration rate of the SBR reactor was controlled at 0.5 L / h, and the sedimentation time was controlled at 1.5 hours. The influent salinity in the 1st to 4th acclimation cycles was 1 ppt, the influent salinity in the 5th to 8th acclimation cycles was 2 ppt, the influent salinity in the 9th to 12th acclimation cycles was 5 ppt, and the influent salinity in the 13th to 16th acclimation cycles was 10 ppt. ppt, the influent salinity was 15 ppt in the 17th-20th acclimation cycle, 20 ppt in the 20th-24th acclimation cycle, and controlled at 25 ppt in the 24th-28th cycle. After the acclimation, the salinity-acclimated activated sludge concentrate was obtained.

[0063] The immobilized bacteria pellets in this example were used for ecological restoration of marine aquaculture water bodies. 400 mL of artificial aquaculture tail water was added to a filtration bottle, and 20 g of the immobilized bacteria pellets were evenly added to the filtration bottle. A peristaltic pump was used to continuously and quantitatively feed water into the filtration bottle. The temperature in the filtration bottle was controlled at 20-30°C, HRT = 24 h, the incubation time was 8 days, each cycle was 2 days, and samples were taken every 1 or 2 days for analysis to determine the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:5, 1:20.

[0064] The combined ecological floating bed in this embodiment was used for ecological restoration of marine aquaculture water bodies. The combined ecological floating bed was placed in a reactor. 80 L of artificial aquaculture tail water was added to the reactor. 4 kg of bacterial immobilization pellets were evenly placed in 28 bait cages. A peristaltic pump was used to achieve continuous quantitative water inflow and outflow in the reactor. The temperature in the reactor was controlled at 20-30°C, the hydraulic retention time HRT was 24 h, each cycle was 2 days, and samples were taken every 2 days for analysis. The incubation time was 16 days. The NH4 + -N, TP and TN content.

[0065] Example 5

[0066] The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 4. The difference from Example 4 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 200 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:5, 1:10.

[0067] Example 6

[0068] The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 4. The difference from Example 4 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 1000 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:5, 1:50.

[0069] Example 7

[0070] This embodiment provides a combined ecological floating bed, such as Figure 16 As shown, it includes a float and a bioburden layer. The float consists of a PVC tube 1, a floating plate 2 and 28 bait cages 3. The floating plate 2 is formed in a rectangular shape. The PVC tube 1 is surrounded by the floating plate 2. The floating plate 2 is provided with 35 aquatic plant fixing holes 6. When in use, the PVC tube 1 and the floating plate 2 are fixed to the upper surface of the fishing net 4, and the 28 bait cages 3 are fixed to the lower surface of the fishing net 4; the bioburden layer includes seahorse teeth 5 and bacteria immobilization pellets. The seahorse teeth 5 are placed in the aquatic plant fixing holes, and the bacteria immobilization pellets are placed in the bait cages 3.

[0071] The method for preparing bacteria-immobilized pellets in the combined ecological floating bed of this embodiment comprises the following steps: S1, 29 mL of salinity-acclimated activated sludge concentrate and 71 mL of 28 g / L sodium alginate aqueous solution were mixed evenly to form a mixed solution; S2. Use a 10 mL PP burette to drop the mixed solution in step D1 into a pre-cooled 2% CaCl2 and 2% BaCl2 solution. After stirring for a certain time of 2 hours, place it in a 0-4 ° C refrigerator to solidify and cross-link for 24 hours, and then rinse with distilled water to obtain a certain number of bacteria-immobilized beads.

[0072] The method for preparing salinity-acclimated activated sludge concentrate in this embodiment comprises the following steps: D1. Prepare culture medium: Dissolve 47.8 mg NH4Cl, 11 mg KH2PO4, 320 mg NaOAc, 20 mg MgSO4·7H2O, and 10 mg CaCl2 in 1 L artificial seawater. Add 1 mL of nutrient solution to prepare salinity-acclimated culture medium. The salinity is adjusted as the experiment progresses. The nutrient solution contains 1500 mg / L FeCl3·6H2O, 150 mg / L H3BO3, 30 mg / L CuSO4·5H2O, 180 mg / L KI, 120 mg / L MnCl2·4H2O, 60 mg / L Na2MoO4·2H2O, 120 mg / L ZnSO4·7H2O, and 150 mg / L CoCl2·6H2O. D2. Salinity acclimation: The activated sludge was placed in an SBR reactor filled with the culture medium in step D1, the 30-min sludge settling ratio SV30 of the activated sludge was 46%, the concentration was 7050 mg / L, and the non-volatile suspended solids concentration was 3500 mg / L. An intermittent acclimation method was used for 28 acclimation cycles, with one cycle running per day. The duration of each cycle was 12 hours. The acclimation cycle included 15 minutes of water inflow, 3.5 hours of anoxic conditions, 1.5 hours of good culture, and 15 minutes of drainage. The anoxic conditions and good culture conditions were alternated twice each. At the same time, the aeration rate of the SBR reactor was controlled at 0.5 L / h, and the sedimentation time was controlled at 1.5 hours. The influent salinity in the 1st to 4th acclimation cycles was 1 ppt, the influent salinity in the 5th to 8th acclimation cycles was 2 ppt, the influent salinity in the 9th to 12th acclimation cycles was 5 ppt, and the influent salinity in the 13th to 16th acclimation cycles was 10 ppt. ppt, the influent salinity was 15 ppt in the 17th-20th acclimation cycle, 20 ppt in the 20th-24th acclimation cycle, and controlled at 25 ppt in the 24th-28th cycle. After the acclimation, the salinity-acclimated activated sludge concentrate was obtained.

[0073] The bacteria-immobilized pellets in this example were used for ecological restoration of marine aquaculture water bodies. 400 mL of artificial aquaculture tail water was added to a filtration bottle, and 20 g of bacteria-immobilized pellets were evenly added to the filtration bottle. A peristaltic pump was used to continuously and quantitatively feed water into the filtration bottle. The temperature in the filtration bottle was controlled at 20-30°C, the hydraulic retention time (HRT) was 24 h, the incubation time was 8 days, and each cycle was 2 days. Sampling and analysis were performed every 1 or 2 days to determine the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:2.5, 1:20.

[0074] The combined ecological floating bed in this embodiment was used for ecological restoration of marine aquaculture water bodies. The combined ecological floating bed was placed in a reactor. 80 L of artificial aquaculture tail water was added to the reactor. 4 kg of bacterial immobilization pellets were evenly placed in 28 bait cages. A peristaltic pump was used to achieve continuous quantitative water inflow and outflow in the reactor. The temperature in the reactor was controlled at 20-30 °C and the hydraulic retention time (HRT) was 24 h. Each cycle was 2 days. Sampling and analysis were performed every two days to determine the NH4 + -N, TP and TN content.

[0075] Example 8

[0076] The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 7. The difference from Example 7 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 200 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:2.5, 1:10.

[0077] Example 9 The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this embodiment is exactly the same as that in Example 7. The difference from Example 7 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 1000 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 1:2.5, 1:50.

[0078] Example 10 The preparation method of the combined ecological floating bed and the bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that when the combined ecological floating bed is used for ecological restoration of marine aquaculture water bodies, the bacteria immobilization pellets are strengthened after each cycle, the bacteria immobilization pellets are cleaned and the surface moisture is dried, and the pellets are taken out every 2 days and placed in a solution containing 2% CaCl2 and 2% BaCl2 to be re-fixed for 2 hours, and then rinsed with deionized water 3 times to clean the CaCl2 and BaCl2 solutions on the surface of the pellets, and then put into freshly prepared artificial sewage for recycling in the next step to determine the NH4 + -Changes in the contents of N, TP and TN.

[0079] Example 11 The preparation method of the combined ecological floating bed and the bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that when the combined ecological floating bed is used for ecological restoration of marine aquaculture water bodies, the bacteria immobilization pellets are not strengthened after each cycle and are directly put into the newly prepared artificial sewage for recycling in the next step to measure the NH4 + -Changes in the contents of N, TP and TN.

[0080] Example 12 The preparation method of the combined ecological floating bed and the bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that when the combined ecological floating bed is used for ecological restoration of seawater aquaculture water bodies, the temperature in the reactor is controlled at 3-15°C.

[0081] Example 13 This embodiment provides a combined ecological floating bed, such as Figure 16 As shown, it includes a float and a bioburden layer. The float consists of a PVC tube 1, a floating plate 2 and 28 bait cages 3. The floating plate 2 is formed in a rectangular shape. The PVC tube 1 surrounds the floating plate 2 and is fixedly connected to the edge of the floating plate 2. The floating plate 2 is provided with 35 aquatic plant fixing holes 6. When in use, the PVC tube 1 and the floating plate 2 are fixed to the upper surface of the fishing net 4, and the 28 bait cages 3 are fixed to the lower surface of the fishing net 4; the bioburden layer includes seahorse teeth 5 and bacteria and algae immobilization pellets. The seahorse teeth are placed in the aquatic plant fixing holes, and the bacteria and algae immobilization pellets are placed in the bait cages.

[0082] The method for preparing the immobilized bacteria and algae pellets in the combined ecological floating bed in this embodiment includes the following steps: S1, 9 mL of salinity-acclimated activated sludge concentrate, 5 g of Chlorella vulgaris, and 91 mL of 22 g / L sodium alginate aqueous solution were mixed to form a mixed solution; S2. Use a 10 mL PP burette to drop the mixed solution in step D1 into a pre-cooled 2% CaCl2 and 2% BaCl2 solution. After stirring for a certain time of 1 hour, place it in a 0-4 ° C refrigerator to solidify and cross-link for 24 hours, and then rinse with distilled water to obtain a certain number of bacteria and algae immobilized beads.

[0083] The method for preparing salinity-acclimated activated sludge concentrate in this embodiment comprises the following steps: D1. Prepare culture medium: Dissolve 47.8 mg NH4Cl, 11 mg KH2PO4, 320 mg NaOAc, 20 mg MgSO4·7H2O, and 10 mg CaCl2 in 1 L artificial seawater. Add 1 mL of nutrient solution to prepare salinity-acclimated culture medium. The salinity is adjusted as the experiment progresses. The nutrient solution contains 1500 mg / L FeCl3·6H2O, 150 mg / L H3BO3, 30 mg / L CuSO4·5H2O, 180 mg / L KI, 120 mg / L MnCl2·4H2O, 60 mg / L Na2MoO4·2H2O, 120 mg / L ZnSO4·7H2O, and 150 mg / L CoCl2·6H2O. D2. Salinity acclimation: The activated sludge was placed in an SBR reactor filled with the culture medium in step D1, the 30-min sludge settling ratio SV30 of the activated sludge was 46%, the concentration was 7050 mg / L, and the non-volatile suspended solids concentration was 3500 mg / L. An intermittent acclimation method was used for 28 acclimation cycles, with one cycle running per day. The duration of each cycle was 12 hours. The acclimation cycle included 15 minutes of water inflow, 3.5 hours of anoxic conditions, 1.5 hours of good culture, and 15 minutes of drainage. The anoxic conditions and good culture conditions were alternated twice each. At the same time, the aeration rate of the SBR reactor was controlled at 0.5 L / h, and the sedimentation time was controlled at 1.5 hours. The influent salinity in the 1st to 4th acclimation cycles was 1 ppt, the influent salinity in the 5th to 8th acclimation cycles was 2 ppt, the influent salinity in the 9th to 12th acclimation cycles was 5 ppt, and the influent salinity in the 13th to 16th acclimation cycles was 10 ppt. ppt, the influent salinity was 15 ppt in the 17th-20th acclimation cycle, 20 ppt in the 20th-24th acclimation cycle, and controlled at 25 ppt in the 24th-28th cycle. After the acclimation, the salinity-acclimated activated sludge concentrate was obtained.

[0084] The combined ecological floating bed in this embodiment was used for ecological restoration of marine aquaculture water bodies. First, the combined ecological floating bed was placed in a reactor. 80 L of artificial aquaculture tail water was added to the reactor. 4 kg of bacteria and algae immobilization pellets were evenly placed in 28 bait cages. A peristaltic pump was used to achieve continuous quantitative water inflow and outflow in the reactor. The temperature in the reactor was controlled at 20-30 ° C, the hydraulic retention time HRT = 24 h, each cycle was 2 days (2 days), and samples were taken every 2 days for analysis. The incubation time was 16 days. The NH4 + -Changes in the contents of N, TP and TN.

[0085] Example 14 The preparation method of the combined ecological floating bed and bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 13. The difference from Example 13 is that when the combined ecological floating bed is used for ecological restoration of seawater aquaculture water bodies, the temperature in the reactor is controlled at 3-15°C.

[0086] Example 15 The preparation method of the combined ecological floating bed and the bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 1. The difference from Example 1 is that when the combined ecological floating bed is used for ecological restoration of marine aquaculture water bodies, the hydraulic retention time HRT is controlled to be 72 h.

[0087] Example 16 The preparation method of the combined ecological floating bed and the bacteria immobilization pellets provided in this embodiment is exactly the same as that in Example 13. The difference from Example 13 is that when the combined ecological floating bed is used for ecological restoration of seawater aquaculture water bodies, the hydraulic retention time HRT is controlled to be 72 h.

[0088] Comparative Example 1 This comparative example provides a method for preparing blank pellets, comprising the following steps: S1, 9 mL of ultrapure water and 91 mL of 22 g / L sodium alginate aqueous solution were mixed to form a mixed solution; S2. Use a 10 mL PP burette to drop the mixed solution in step D1 into a pre-cooled 2% CaCl2 and 2% BaCl2 solution. After stirring for a certain time of 1 hour, place it in a 0-4 ° C refrigerator to cure and cross-link for 24 hours, and then rinse with distilled water to obtain a certain number of immobilized beads.

[0089] The blank beads in this comparative example are used for ecological restoration of marine aquaculture water bodies. 400 mL of artificial aquaculture tail water is added to a suction flask, and 20 g of blank beads are evenly put into the suction flask. The reactor is continuously and quantitatively fed with water by a peristaltic pump. Sampling and analysis are performed every 1 day to determine the contents of NH4+-N, TP and TN in the water samples. The incubation time is 8 days, and each cycle is 2 days. The temperature in the suction flask is controlled at 20-30°C, the hydraulic retention time HRT = 24 h, and each cycle is 2 days (2 days). Sampling and analysis are performed every 2 days. When determining the contents of NH4+-N, TP and TN in the water samples, the corresponding data results are marked with 0, 1:20.

[0090] Comparative Example 2 The preparation method of the combined ecological floating bed and bacteria immobilized pellets provided in this comparative example is exactly the same as that in comparative example 1. The difference from comparative example 1 is that the bacteria immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 200 mL of artificial aquaculture tail water is added to the suction filtration bottle, and the NH4 + -N, TP and TN content, the corresponding data results are marked with 0, 1:10.

[0091] Comparative Example 3 The preparation method of the combined ecological floating bed and bacteria-immobilized pellets provided in this comparative example is exactly the same as that in comparative example 1. The difference from comparative example 1 is that the bacteria-immobilized pellets are used for ecological restoration of seawater aquaculture water bodies, 1000 mL of artificial aquaculture tail water is added to the filtration bottle, and when the NH4+-N, TP and TN contents in the water sample are measured, the corresponding data results are marked with 0, 1:50.

[0092] Comparative Example 4 The preparation method of the combined ecological floating bed and the bacteria immobilized beads provided in this comparative example is exactly the same as that in comparative example 1. The difference from comparative example 1 is that when the combined ecological floating bed is used for ecological restoration of marine aquaculture water bodies, the immobilized beads are strengthened after each cycle, the immobilized beads are cleaned and the surface moisture is dried, and the beads are taken out every 2 days and placed in a solution containing 2% CaCl2 and 2% BaCl2 to be re-fixed for 2 hours, rinsed with deionized water 3 times, the CaCl2 and BaCl2 solutions on the surface of the beads are washed off, and the beads are put into freshly prepared artificial sewage for recycling in the next step to determine the NH4 + -Changes in the contents of N, TP and TN.

[0093] Comparative Example 5 The preparation method of the combined ecological floating bed and bacteria immobilization balls provided in the comparative example is exactly the same as that of comparative example 1. The difference from comparative example 1 is that when the combined ecological floating bed is used for ecological restoration of seawater aquaculture water bodies, no reinforcement is performed and no continuous water inlet and outlet is performed.

[0094] Comparative Example 6 The difference between this comparative example and Example 15 is that there are no seahorse teeth in the combined ecological floating bed.

[0095] Comparative Example 7 The difference between this comparative example and Example 16 is that there are no seahorse teeth in the combined ecological floating bed.

[0096] Comparative Example 8 The difference between this comparative example and Example 1 is that there are no seahorse teeth in the combined ecological floating bed.

[0097] Comparative Example 9 The difference between this comparative example and Example 13 is that there are no seahorse teeth in the combined ecological floating bed.

[0098] The data structure of the content of NH4+-N, TP and TN in the water samples detected in the examples and comparative examples was analyzed, and the results were as follows: Figure 1 The following graph shows the changes in NH₄⁺-N removal rates in water samples from Examples 1-9 and Comparative Examples 1-3. As can be seen, with the exception of the blank control group for Comparative Examples 1-3, the NH₄⁺-N removal rates of all other examples approached 100% after two days. Because the alginate chains within the immobilized bacteria beads contain numerous carboxyl and hydroxyl groups, they carry a negative charge in a weakly alkaline environment and possess a certain adsorption and binding capacity for cationic substances (NH₄⁺). This increases the NH₄⁺-N concentration within the immobilized bacteria beads, boosting the ammonia oxidation reaction rate and increasing the NH₄⁺-N conversion rate.

[0099] Figure 2 The following data shows the changes in TN removal rates in water samples from Examples 1-9 and Comparative Examples 1-3. As can be seen from the figure, over three days, the TN removal rates of the combined ecological floating beds in each of the Examples and Comparative Examples gradually increased. With the exception of the blank control group, Comparative Examples 1-3, the TN removal rates in Examples 1-6 all reached over 80% after two days, with the highest reaching 88.0%. While increasing the ammonia oxidation reaction rate in Examples 1-6, this also improved denitrification efficiency, boosting TN conversion.

[0100] Figure 3 The TP removal rate change data of the water samples of Examples 1-9 and Comparative Examples 1-3 are shown in the figure. As can be seen from the figure, within 3 days, the TP removal rate of the combined ecological floating bed in each Example and Comparative Example gradually decreased. In Examples 1-9, the TP removal rate of the combined ecological floating bed in Example 2 reached the highest TP removal rate of 89.9% after two days. This is because the bacteria immobilization pellets contain a large amount of Ba 2+ and Ca 2+ , easy with PO4 3-Adsorption and binding make it easier for polyphosphate bacteria in activated sludge to utilize it, thereby improving TP conversion rate. The TP removal rate in the comparative examples is generally higher than that in the examples. It is speculated that the possible reason is that the sludge has absorbed a certain amount of TP during the acclimation process, resulting in its absorption and treatment rate being lower than that of the blank pellets in the comparative examples.

[0101] Figure 4 NH4 in the water samples of Comparative Example 4, Comparative Example 5, Example 10 and Example 11 + -N removal rate change data chart. Among them, the enhanced group is Example 10 and Comparative Example 4, and the non-enhanced group is Example 11 and Comparative Example 5. It can be seen from the figure that after recycling for 2 times (4 days), the comparative example 5 has a significant effect on NH4 + -N removal rate decreased from 99.5% to 87.9%, and after using it twice, the blank pellets in Comparative Example 5 softened, collapsed and broke, and could not be recycled for the next step. After recycling it for 4 times (8 days), the bacteria-immobilized pellets in Example 11 + The -N removal rate was close to 100%, and the bacteria-immobilized pellets softened but did not collapse or break significantly, indicating that the activated sludge had a certain strengthening effect on the structure of the sodium alginate pellets. + -N removal rate is higher than that of the comparative example 5 without strengthening; after 8 days of circulation, the bacteria immobilized beads NH4 in the embodiment 10 of the strengthening group were + The -N removal rates were close to 100%. During the pellet recycling process, it was found that the blank pellets in Comparative Example 4 were more severely broken than the bacteria-immobilized pellets in Examples 10 and 11, resulting in a decrease in adsorption capacity. After three cycles, the blank pellets in Comparative Example 4 had completely softened and broken and could not be recycled.

[0102] Figure 5The following is a data graph showing the changes in TN removal rates in water samples from Comparative Example 4, Comparative Example 5, Example 10, and Example 11. The enhanced groups are Example 10 and Comparative Example 4, and the non-enhanced groups are Example 11 and Comparative Example 5. As can be seen from the figure, after the non-enhanced group was recycled twice, the TN removal rate of the blank beads in Comparative Example 5 decreased from 67.4% to 42.4%. After being used twice, the blank beads softened, their structure collapsed and cracked, making them unable to be recycled in the next step. After being recycled four times, the TN removal rate of the bacteria-immobilized beads in Example 11 decreased from 88.4% to 68.6%. The bacteria-immobilized beads softened but did not significantly collapse or crack. In the enhanced group, after being recycled three times, the TN removal rate of the blank beads in Comparative Example 4 decreased from 74.0% to 46.8%. After being recycled four times, the TN removal rate of the bacteria-immobilized beads in Example 11 decreased from 88.4% to 77.5%. As the beads were recycled, the TN removal rates of the beads decreased to varying degrees. Activated sludge has a certain reinforcing effect on the structure of bacteria-immobilized balls.

[0103] Figure 6 The following is a data graph showing the changes in TP removal rates in the water samples of Comparative Example 4, Comparative Example 5, Example 10, and Example 11. Among them, the enhanced group is Example 10 and Comparative Example 4, and the non-enhanced group is Example 11 and Comparative Example 5. As can be seen from the figure, in the non-enhanced group, after two cycles of use, the TP removal rate of the blank beads in Comparative Example 5 decreased from 93.9% to 61.0%. After two uses, the blank beads softened, collapsed, and broke, making them unable to be recycled in the next step. After four cycles, the TP removal rate of the bacteria-immobilized beads in Example 11 decreased from 91.1% to 78.9%. The bacteria-immobilized beads softened and shrank but did not collapse or break significantly. Activated sludge has a certain reinforcing effect on the structure of sodium alginate beads.

[0104] In the enhanced group, after three cycles of use, the blank balls in comparative example 4 had a higher removal rate of TP (>90%). During the solidification process, the solution contained a large amount of CaCl2 and BaCl2. 2+ and Ca 2+ The -OH at the site can react with negatively charged PO4 3- Ligand exchange is performed. 2+ and Ca 2+ Combined with phosphate, hydrogen phosphate and dihydrogen phosphate, inorganic phosphorus is converted into Ba-P and Ca-P. Therefore, in the solidification process of the ball after each cycle, the ball structure is strengthened and the Ba inside the ball is 2+ and Ca 2+ After four cycles of use, the TN removal rate of the bacteria-immobilized beads in Example 10 decreased from 92.2% to 81.2%. As the beads were recycled, the TN removal rate of the beads decreased to varying degrees.

[0105] Figure 7 NH4 in the water samples of Example 1 and Example 13 + -N removal rate change data chart. As can be seen from the figure, after being recycled for 2 times, the bacteria-immobilized beads in Example 1 and the algae-bacteria-immobilized beads doped with algae powder in Example 13 have NH4 + -N removal rates are close to 100%.

[0106] Figure 8 The following graph shows the changes in TN removal rates in the water samples from Examples 1 and 13. As can be seen from the graph, after two cycles, the TN removal rate of the bacteria-immobilized beads in Example 1 decreased from 88.4% to 82.5%, while the TN removal rate of the bacteria-immobilized beads in Example 13 decreased from 80.8% to 78.1%. With each cycle of the beads, the TN removal rates decreased to varying degrees.

[0107] Figure 9 The following is a graph showing the change in TP removal rates in the water samples of Example 1 and Example 13. As can be seen from the graph, after two cycles, the TP removal rate of the bacteria-immobilized beads in Example 1 dropped from 91.1% to 89.6%, while the TP removal rate of the bacteria-immobilized beads in Example 13 dropped from 91.4% to 89.8%.

[0108] comprehensive Figure 7-9 The data in the table show that the bacteria-immobilized beads and the bacteria-algae-immobilized beads are more effective in removing NH4 + There is not much difference in the effects of -N, TN and TP.

[0109] Figure 10 NH4 in the water samples of Examples 1, 12, 13 and 14 + -N removal rate change data chart. Among them, the summer group is Example 1 and Example 13, and the winter group is Example 12 and Example 14. As can be seen from the figure, the bacteria-immobilized beads in Example 1 and the bacteria-algae-immobilized beads with algae powder added in Example 13 have a significant effect on NH4 removal in the summer group within 9 days. + -N removal rates were > 98.4%; in the winter group, within 18 days, the bacteria-immobilized pellets in Example 12 and the bacteria-algae-immobilized pellets with algae powder added in Example 14 removed NH4 + -N removal rate was the highest on the 6th day (80.1% and 82.4% respectively). Compared with summer, the ammonia oxidation reaction rate is lower in winter, which reduces NH4 + -N removal rate.

[0110] Figure 11The following is a data chart showing the change in TN removal rate in water samples from Examples 1, 12, 13, and 14. The summer group includes Examples 1 and 13, while the winter group includes Examples 12 and 14. As can be seen from the figure, within 9 days in the summer group, the TN removal rates of the bacteria-immobilized pellets in Example 1 and the bacteria-algae-immobilized pellets with algae powder added in Example 13 reached their highest values ​​on the 3rd day (75.7% and 74.8%, respectively). Within 18 days in the winter group, the TN removal rates of the bacteria-immobilized pellets in Example 12 and the bacteria-algae-immobilized pellets with algae powder added in Example 14 reached their highest values ​​on the 8th day (54.3% and 46.5%, respectively). Compared to summer, lower temperatures and NH4 + The decrease in -N conversion rate leads to a decrease in TN removal rate.

[0111] Figure 12 The following is a data chart showing the changes in TP removal rates in water samples from Examples 1, 12, 13, and 14. The summer group includes Examples 1 and 13, while the winter group includes Examples 12 and 14. As can be seen from the figure, within 9 days in the summer group, the bacteria-immobilized pellets from Example 1 and the bacteria-algae-immobilized pellets with algae powder added in Example 13 had the highest TN removal rates, which were 70.6% and 69.4%, respectively. In the winter group, within 18 days, the bacteria-immobilized pellets from Example 12 and the bacteria-algae-immobilized pellets with algae powder added in Example 14 had the highest TP removal rates on the 8th day (49.1% and 41.6%, respectively). Compared to summer, winter has lower temperatures and NH4 + The decrease in -N conversion rate leads to a decrease in TP removal rate.

[0112] Figure 13 NH4 in the water samples of Example 15, Example 16, and Comparative Examples 6-9 + -N removal rate change data chart. Under hydraulic retention time HRT = 24h, within 16 days, the bacteria immobilized pellets in comparative example 8 and the bacteria-algae immobilized pellets with algae powder added in comparative example 9 removed NH4 + The highest removal rates of -N were 69.0% and 67.5%. By adjusting the flow rate of artificial aquaculture tail water and controlling HRT = 72h, within 12 days, the bacteria-immobilized pellets (without seahorse teeth) in Comparative Example 6, the bacteria-algae-immobilized pellets (without seahorse teeth) in Comparative Example 7, the bacteria-immobilized pellets (seahorse teeth) in Example 15, and the bacteria-algae-immobilized pellets (seahorse teeth) in Example 16 were significantly improved in terms of NH4 + -N removal rates were as high as 90.9%, 91.6%, 92.3% and 92.5% respectively. Increasing hydraulic retention time and using seahorse teeth are beneficial to improving NH4 + -N removal rate.

[0113] Figure 14The following data shows the changes in TN removal rates in the water samples from Examples 15, 16, and Comparative Examples 6-9. At a hydraulic retention time (HRT) of 24 hours, the bacteria-immobilized pellets in Comparative Example 8 and the algae-immobilized pellets with algae powder added in Comparative Example 9 achieved the highest TN removal rates of 24.8% and 21.8% over 16 days. By adjusting the flow rate of the artificial aquaculture tailwater to control the HRT to 72 hours, the bacteria-immobilized pellets in Comparative Example 6 (without seahorse teeth), the bacteria-immobilized pellets in Comparative Example 7 (without seahorse teeth), the bacteria-immobilized pellets in Example 15 (with seahorse teeth), and the bacteria-immobilized pellets in Example 16 (with seahorse teeth) achieved the highest TN removal rates of 54.3%, 46.5%, 59.2%, and 52.9%, respectively, over 12 days. Increasing the HRT and the presence of seahorse teeth can improve TN removal rates, with both algae powder and seahorse teeth promoting TN removal.

[0114] Figure 15 The following data shows the changes in TP removal rates in the water samples from Examples 15, 16, and Comparative Examples 6-9. At a hydraulic retention time (HRT) of 24 hours, the bacteria-immobilized pellets in Comparative Example 8 and the algae-immobilized pellets with algae powder added in Comparative Example 9 achieved the highest TP removal rates of 41.4% and 37.2% over 16 days. By adjusting the flow rate of the artificial aquaculture tailwater to control the HRT to 72 hours, the bacteria-immobilized pellets in Comparative Example 6 (without seahorse teeth), the bacteria-immobilized pellets in Comparative Example 7 (without seahorse teeth), the bacteria-immobilized pellets in Example 15 (with seahorse teeth), and the bacteria-immobilized pellets in Example 16 (with seahorse teeth) achieved the highest TP removal rates of 49.1%, 41.6%, 58.5%, and 52.8%, respectively, over 12 days. Increasing the hydraulic retention time (HRT) and using seahorse teeth can improve TP removal rates, with both algae powder and seahorse teeth promoting TP removal.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A combined ecological floating bed, characterized in that: The ecological floating bed includes a float and a bioburden layer. The float enables the combined ecological floating bed to float on the surface of the water body and provides growth space for the bioburden layer. The bioburden layer includes seahorse teeth and immobilized balls. The immobilized balls include bacteria-immobilized balls and / or bacteria-algae immobilized balls. The raw materials of the bacteria-immobilized balls include salinity-acclimated activated sludge and sodium alginate. The raw materials of the bacteria-algae immobilized balls include salinity-acclimated activated sludge, chlorella and sodium alginate.

2. The combined ecological floating bed according to claim 1, characterized in that: The float consists of a PVC tube, a float plate and several bait cages. The PVC tube surrounds the float plate, and the float plate is provided with multiple aquatic plant fixing holes. When in use, the PVC tube and the float plate are fixed on the upper surface of the fishing net, and several bait cages are fixed on the corresponding lower surfaces of the fishing net; the seahorse teeth are placed in the aquatic plant fixing holes, and the immobilized balls are placed in the bait cages.

3. The combined ecological floating bed according to claim 1, characterized in that: The immobilized beads are prepared by the following method: S1, mixing salinity-acclimated activated sludge concentrate with sodium alginate solution, or mixing salinity-acclimated activated sludge concentrate, Chlorella and sodium alginate solution to form a mixed solution; the concentration of the sodium alginate solution is 20-30 g / L, the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution in the mixed solution is 1:(2-20), and the concentration of the Chlorella in the mixed solution is 30-50 g / L; S2. Dropping the mixed solution in step S1 into a solution containing CaCl2 and BaCl2, wherein the mass percentage of CaCl2 in the solution is 1%-5%, and the mass percentage of BaCl2 in the solution is 1%-5%, stirring and mixing evenly, and then cross-linking and curing at a temperature of 0-10°C to obtain immobilized beads.

4. The combined ecological floating bed according to claim 3, characterized in that: The salinity-acclimated activated sludge concentrate in step S1 is prepared by the following method: D1. Prepare culture medium: dissolve NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in artificial seawater to form a mixture, and add nutrient solution to the mixture to prepare salinity-acclimated culture medium; the concentrations of NH4Cl, KH2PO4, NaOAc, MgSO4·7H2O, and CaCl2 in the mixture are 45-50 mg / L, 10-15 mg / L, 300-350 mg / L, 20-25 mg / L, and 1-3 mg / L, respectively; D2. Salinity acclimation: Activated sludge is placed in an SBR reactor filled with the culture solution described in step D1, wherein the activated sludge has a 30-min sludge settling ratio (SV30) of 40-50%, a concentration of 7000-7100 mg / L, and a non-volatile suspended solids concentration of 3400-3600 mg / L. An intermittent acclimation method is used for multiple acclimation cycles, each of which includes water intake, anoxic conditions, culture, and drainage processes. The influent salinity gradually increases during the multiple acclimation cycles, and the influent salinity is 1-25 ppt. After the acclimation is completed, a salinity-acclimated activated sludge concentrate is obtained.

5. The combined ecological floating bed according to claim 3, characterized in that: The solvent of the sodium alginate solution in step S1 is water, the concentration of the sodium alginate solution is 20 g / L, and the volume ratio of the salinity-acclimated activated sludge concentrate to the sodium alginate solution is 1:

10.

6. The combined ecological floating bed according to claim 3, characterized in that: The cross-linking and curing in step S2 is carried out at a temperature of 0-4°C and for a time of ≥20 h.

7. An application of the combined ecological floating bed according to any one of claims 1 to 6 in the ecological restoration of marine aquaculture water bodies, characterized in that: The following steps are involved: The float of the combined ecological floating bed is placed in a reactor, aquaculture tail water is added into the reactor, and the seahorse teeth and the immobilized balls are added into the float to repair the aquaculture tail water.

8. The use according to claim 7, characterized in that The mass volume ratio of the immobilized beads to the aquaculture tail water is 1:(5-25) g / mL.

9. The use according to claim 7, characterized in that The immobilized beads are recycled after strengthening, and the strengthening process is to place the immobilized beads in a solution containing CaCl2 and BaCl2 for fixation, wherein the mass percentage of CaCl2 in the solution is 1%-5%, and the mass percentage of BaCl2 is 1%-5%.

10. The use according to claim 9, characterized in that The hydraulic retention time of the aquaculture tail water in the reactor is 8-96 h.

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