Sulfur autotrophic carrier based on water quality purification of seawater fish tank as well as preparation method and application of sulfur autotrophic carrier

Abstract

The invention relates to the technical field of water quality purification, and provides a sulfur autotrophic carrier based on seawater fish tank water quality purification and a preparation method and application thereof.The sulfur autotrophic carrier comprises, by weight, 30-50 parts of sulfur, 20-40 parts of hydrogen peroxide modified coral bone, 20-40 parts of a pH buffering agent, 1-3 parts of a pore forming agent and 5-10 parts of a binder. The hydrogen peroxide modified coral bone is added into the sulfur autotrophic carrier, so that the quantity of pore channels of the coral bone can be increased, the attachment points of autotrophic denitrifying bacteria are increased, and the water quality purification capacity is further improved; and the coral bones can slowly release carbonate radicals, so that the pH value in the fish tank can be stabilized, a proper acid-base environment is provided for the activity of the autotrophic denitrifying bacteria, and the water quality purification capability of the autotrophic denitrifying bacteria is improved.

Description

Technical Field

[0001] The invention relates to the technical field of water purification, and in particular to a sulfur autotrophic carrier based on seawater fish tank water purification, and a preparation method and application thereof. Background Art

[0002] In a marine fish tank, water quality directly affects the growth and health of fish. In order to keep the water clean, it is usually necessary to change the water regularly and add filter materials. At present, the main water purification methods on the market include physical filtration, chemical filtration and biological filtration. However, in the case of high salt in a marine fish tank, microorganisms increase slowly, and traditional filter materials often cannot completely remove harmful substances in the water. They are easily saturated and need to be replaced frequently. The operation is complicated, which brings inconvenience to fish lovers. Therefore, the development of an efficient and long-lasting water purification material is of great significance to improving the water quality of marine fish tanks. Sulfur autotrophy, as a new type of biological purification technology, can utilize the characteristics of sulfur autotrophic bacteria to effectively remove nitrate nitrogen and nitrite nitrogen pollutants in water without the need for additional carbon sources, maintain water cleanliness and ecological balance, and is suitable for water purification in aquariums.

[0003] The sulfur autotrophic biofiltration system that relies on heterotrophic microorganisms has limited efficiency in removing nitrates and nitrites; when the carbon-nitrogen ratio is low, the denitrification rate is low, and there is a situation of salt accumulation that affects aquatic organisms; the use of heterotrophic denitrification requires a continuous supply of carbon sources, which increases the cost of use; although traditional chemical treatment methods can effectively reduce the concentration of harmful substances in water, long-term use will destroy the ecological balance of water quality and cause potential harm to aquatic organisms. At the same time, the continuous investment of chemicals also increases operating costs. In addition, in high-salinity seawater fish tanks, biofilms form slowly, and their stability and efficiency may be affected by factors such as water flow and temperature changes. The existing technology is complicated in use and maintenance, and requires regular chemical treatment or physical cleaning. Therefore, there is a need for a sulfur autotrophic carrier that does not require an external carbon source, has fast biofilm formation, and has high biofilm adhesion and stability. Summary of the invention

[0004] In view of this, the present invention proposes a sulfur autotrophic carrier based on seawater fish tank water purification, which does not require an external carbon source, has fast biofilm formation, and has high biofilm adhesion and stability, and a preparation method thereof.

[0005] The technical solution of the present invention is implemented as follows: In the first aspect, the present invention provides a sulfur autotrophic carrier based on marine fish tank water purification, which comprises 30 to 50 parts of sulfur, 20 to 40 parts of hydrogen peroxide-modified coral bones, 20 to 40 parts of pH buffer, 1 to 3 parts of pore-forming agent and 5 to 10 parts of binder, calculated by weight.

[0006] Specifically, hydrogen peroxide-modified coral skeletons not only help stabilize pH values ​​in water purification applications, but also have a positive impact on nitrate degradation, which is related to their porous structure and modification method.

[0007] The modified coral skeleton has a larger specific surface area, which provides more attachment points for autotrophic denitrifying bacteria and supports the growth and reproduction of the bacteria. Autotrophic denitrifying bacteria are key to nitrate degradation. They can use nitrate as an electron acceptor and reduce it to nitrogen gas. The oxidation of hydrogen peroxide helps to remove organic matter that blocks the pores of the coral skeleton, which not only increases the porosity, but also improves the fluidity of the water body, which is conducive to the denitrification process. The slow release of carbonate from the coral skeleton helps maintain a stable alkaline environment, which is conducive to the metabolic activity of autotrophic denitrifying bacteria. At the same time, an alkaline environment is also necessary for the denitrification process, because most denitrifying microorganisms are most active under neutral or slightly alkaline conditions.

[0008] Therefore, hydrogen peroxide-modified coral skeletons not only contribute to pH stabilization but also improve nitrate removal efficiency by supporting the activities of autotrophic denitrifying organisms.

[0009] On the basis of the above technical solution, preferably, the preparation method of the hydrogen peroxide-modified coral bone is:

[0010] S1, placing the coral bone powder in a beaker, adding a hydrogen peroxide solution with a volume concentration of 20%-40% to cover the coral bone powder, and then shaking at 20°C-30°C for 8-10 hours and filtering the reaction solution;

[0011] S2, washing the filtered coral bones with water until the pH value of the filtrate is 7, and then drying the water and crushing and sieving with a grinder to obtain hydrogen peroxide-modified coral bones with a particle size of 100-200 mesh.

[0012] On the basis of the above technical solution, preferably, the pH buffer is one of heavy calcium carbonate, calcium hydroxide, sodium carbonate and magnesium carbonate, the pore-forming agent is gypsum, and the binder is sodium silicate or potassium silicate.

[0013] Specifically, the main role of gypsum in sulfur autotrophic carriers is as a pore-forming agent and skeleton material, and it also has a certain positive effect on nitrate degradation.

[0014] During the heating process, gypsum loses its crystal water to form a porous structure, which provides more space for microorganisms to grow; although gypsum itself does not directly participate in the chemical degradation of nitrates, the porous environment it provides is conducive to the attachment and growth of denitrifying bacteria, thereby indirectly promoting the biodegradation of nitrates. Gypsum enhances the mechanical strength of the carrier, enabling it to better resist the impact of water flow; this stable structure helps maintain the integrity and activity of the microbial community, indirectly supporting the continuous degradation of nitrates. By providing a stable physical structure, gypsum helps maintain an environment suitable for microbial growth; this stability is beneficial to the continued progress of the denitrification process.

[0015] In summary, gypsum indirectly supports the nitrate degradation process by improving the physical properties of the carrier and providing a suitable environment for microbial growth.

[0016] In a second aspect, the present invention provides a method for preparing a sulfur autotrophic carrier based on marine fish tank water purification, comprising the following steps:

[0017] S1, pre-treating the raw materials: crushing and sieving the sulfur, pH buffer, pore-forming agent, and binder respectively to obtain a powder material with a particle size of 100-200 mesh;

[0018] S2, prepare a binder solution with a mass concentration of 30%-50%, then place the raw materials in step S1 in a mixer, stir evenly, add the prepared binder solution and stir evenly again;

[0019] S3, the product obtained in step S2 is extruded and formed by a granulator, and then dried to obtain a sulfur autotrophic carrier with a particle size of 3-5 mm.

[0020] In a third aspect, the present invention provides an application of a sulfur autotrophic carrier based on marine fish tank water purification in marine fish tank water purification, wherein the sulfur autotrophic carrier is used for marine fish tank water purification after biofilm formation.

[0021] On the basis of the above technical solution, preferably, the biofilm forming method comprises the following steps:

[0022] S1, preparing biofilm nutrient solution, the components of which are KNO3, KH2PO4 and sea salt;

[0023] S2, placing the sulfur autotrophic carrier in the biofilm-forming nutrient solution;

[0024] S3, adding 5%-15% volume fraction of autotrophic denitrifying bacteria agent to the carrier nutrient solution mixing system, and then placing the entire system at 20°C-30°C for static cultivation;

[0025] S4, regularly check the concentrations of ammonia nitrogen, nitrite, nitrate and total nitrogen in the system, and control the pH of the system at 7-7.5 throughout the process; when the total nitrogen concentration in the system drops by 80%, add KNO3, and repeat 3 times to determine that the biofilm is complete.

[0026] On the basis of the above technical scheme, preferably, the autotrophic denitrifying bacteria agent is a mixture of sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004; the preservation number of the SZG-SAD-001 is CCTCCNO: M2022806, and the preservation number of the SZG-SAD-004 is CCTCCNO: M2023992.

[0027] On the basis of the above technical solution, preferably, the mass ratio of the sulfur-oxidizing monas SZG-SAD-001:thiobacillus denitrifying SZG-SAD-004 is 1:1-2.

[0028] On the basis of the above technical scheme, preferably, the number of viable bacteria in the bacterial solution of sulfur-oxidizing monospores SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 is ≥10 8 CFU / g.

[0029] On the basis of the above technical scheme, preferably, the contents of each component in the biofilm nutrient solution are: KNO3 0.5-1g / L, KH2PO4 0.005-0.01g / L, and sea salt 30g / L.

[0030] The sulfur autotrophic carrier based on seawater fish tank water purification of the present invention and its preparation method and application have the following beneficial effects compared with the prior art:

[0031] (1) The sulfur autotrophic carrier provided by the present invention is added with coral bones modified by hydrogen peroxide. The coral bones themselves have a porous structure. Hydrogen peroxide can be used to oxidize the organic matter that blocks the pores in the coral bones, remove some impurities, increase the number of coral bone pores, and then increase the specific surface area, providing a large number of attachment points for autotrophic denitrifying bacteria. In addition, the coral bones are alkaline materials that can slowly release carbonate ions, which helps to stabilize the pH value in the fish tank. In addition, the coral bones also have the ability to absorb suspended impurities, which helps to improve the clarity of the water quality in the fish tank.

[0032] (2) The porogen of the sulfur autotrophic carrier of the present invention is gypsum. Gypsum loses crystal water during heating. When the water molecules inside the gypsum crystals are removed, a porous structure is formed, so that the heated gypsum has a high porosity, providing a large amount of growth space for microorganisms. In addition, as the reaction proceeds, the substances in the carrier are continuously consumed. Adding gypsum can also serve as a skeleton material for the carrier in the later stage, enhance the mechanical strength of the carrier, and improve the ability of the carrier to resist water flow impact.

[0033] (3) The present invention promotes the rapid formation of salt-tolerant biofilms by adding sulfur-autotrophic denitrifying bacteria: sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004, and adopts an artificial biofilm formation method in an environment simulating a seawater fish tank, thereby quickly starting denitrification; the carrier after biofilm formation can be directly used for seawater fish tank water purification without the need to add other substances and bacterial agents, and the operation is simple.

[0034] (4) The sulfur autotrophic denitrification functional biological carrier material prepared by the present invention can effectively remove nitrite nitrogen and nitrate nitrogen pollutants in a seawater fish tank without adding an external carbon source, thereby purifying the water quality of the fish tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a diagram showing the effect of the sulfur autotrophic carrier in purifying water in Example 1;

[0037] Figure 2 This is a diagram showing the effect of the sulfur autotrophic carrier in comparative example 1 in purifying water quality;

[0038] Figure 3 This is a diagram showing the effect of the sulfur autotrophic carrier in water purification in Comparative Example 2;

[0039] Figure 4 This is a diagram showing the effect of water purification by the sulfur autotrophic carrier of Comparative Example 3;

[0040] Figure 5 This is a diagram showing the effect of the sulfur autotrophic carrier of Comparative Example 4 in purifying water quality. DETAILED DESCRIPTION

[0041] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The sulfur-oxidizing monas SZG-SAD-001 and denitrifying Thiobacillus SZG-SAD-004 used in the present invention are both from the self-developed strains of Mizunokumi. Among them, the sulfur-oxidizing monas SZG-SAD-001 is sulfur-oxidizing monas (Sulfurimonas sp.) SZG-SAD-001, which was deposited in the China Center for Type Culture Collection (CCTCC) on June 7, 2022 (address: Wuhan University, Wuhan, China, postal code: 430072), and the collection number is: CCTCC No. 2022806.

[0043] Thiobacillus denitrificans SZG-SAD-004 is Thiobacillus denitrificans SZG-SAD-004, which was deposited in the China Center for Type Culture Collection (CCTCC) (address: Wuhan University, Wuhan, China, postal code: 430072) on June 12, 2023, and the deposit number is: CCTCC No.2023992.

[0044] Example 1

[0045] The components of the sulfur autotrophic carrier of this embodiment are: 50 g of sulfur, 40 g of hydrogen peroxide-modified coral bones, 40 g of pH buffer heavy calcium carbonate, 3 g of pore-forming agent gypsum and 10 g of binder sodium silicate.

[0046] Wherein, the preparation method of the sulfur autotrophic carrier comprises the following steps:

[0047] S1, preparing hydrogen peroxide-modified coral bone: placing coral bone powder in a beaker, adding a hydrogen peroxide solution with a volume concentration of 40% to cover the coral bone powder, then placing it in a constant temperature water bath, maintaining the temperature at 30°C, fully shaking for 10 hours, and then filtering the reaction solution; continuously washing the filtered coral bone with tap water to remove the residual hydrogen peroxide solution until the pH of the filtrate is 7, and then drying the hydrogen peroxide-modified coral bone in an oven at 105°C, and then crushing and sieving with a grinder to obtain hydrogen peroxide-modified coral bone with a particle size of 100 mesh.

[0048] S2, pre-treating the raw materials: crushing the sulfur, pH buffer, pore-forming agent and binder respectively to obtain a powder material with a particle size of 100 meshes.

[0049] S3, preparing a binder solution: dissolving a binder sodium silicate in water to prepare a sodium silicate solution with a mass concentration of 30%, then placing the raw materials in step S1 in a mixer, stirring evenly, adding the prepared binder solution and stirring evenly again.

[0050] S4, the product obtained in step S2 is extruded by a granulator, and then the obtained carrier particles are placed in an oven at 130° C. and dried for 6 hours. After drying, a sulfur autotrophic carrier with a particle size of 3-5 mm is obtained.

[0051] The application of the sulfur autotrophic carrier in the water purification of the seawater fish tank in this embodiment is as follows: the sulfur autotrophic carrier is first formed into a biofilm and then applied to the water purification of the seawater fish tank. The biofilm forming method comprises the following steps:

[0052] S1, prepare biofilm nutrient solution, the components of which are KNO30.7g / L, KH2PO40.008g / L, and sea salt 30g / L;

[0053] S2, placing 100 g of sulfur autotrophic carrier in 1 L of biofilm-forming nutrient solution;

[0054] S3, adding 10% volume fraction of autotrophic denitrifying bacteria to the carrier nutrient solution mixing system, and then placing the entire system at 20℃-30℃ for static culture; the autotrophic denitrifying bacteria agent is a composite bacteria agent formed by mixing sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 in a mass ratio of 1:1, and the number of live bacteria in the bacterial liquid of sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 is ≥108CFU / g.

[0055] S4, regularly check the concentrations of ammonia nitrogen, nitrite, nitrate and total nitrogen in the system, and control the pH of the system at 7 throughout the process; when the total nitrogen concentration in the system drops by 80%, add KNO3, and repeat 3 times to determine that the biofilm is complete.

[0056] Example 2

[0057] The sulfur autotrophic carrier of this embodiment includes 40 g of sulfur, 30 g of hydrogen peroxide-modified coral bones, 30 g of pH buffer calcium hydroxide, 2 g of pore-forming agent gypsum, and 8 g of binder potassium silicate.

[0058] Wherein, the preparation method of the sulfur autotrophic carrier comprises the following steps:

[0059] S1, preparing hydrogen peroxide-modified coral bone: placing coral bone powder in a beaker, adding a hydrogen peroxide solution with a volume concentration of 30% to cover the coral bone powder, then placing it in a constant temperature water bath, maintaining the temperature at 25°C, fully shaking for 8 hours, and then filtering the reaction solution; continuously washing the filtered coral bone with tap water to remove the residual hydrogen peroxide solution until the pH of the filtrate is 7, and then drying the hydrogen peroxide-modified coral bone in an oven at 105°C, and then crushing and sieving with a grinder to obtain hydrogen peroxide-modified coral bone with a particle size of 150 mesh.

[0060] S2, pre-treating the raw materials: crushing the sulfur, pH buffer, pore-forming agent and binder respectively to obtain a powder material with a particle size of 150 meshes.

[0061] S3, preparing a binder solution: dissolving a binder potassium silicate in water to prepare a sodium silicate solution with a mass concentration of 40%, then placing the raw materials in step S1 in a mixer, stirring evenly, adding the prepared binder solution and stirring evenly again;

[0062] S4, the product obtained in step S2 is extruded by a granulator, and then the obtained carrier particles are placed in an oven at 130° C. and dried for 6 hours. After drying, a sulfur autotrophic carrier with a particle size of 3-5 mm is obtained.

[0063] The application of sulfur autotrophic carrier in the water purification of marine fish tanks is to form a biofilm on the sulfur autotrophic carrier and apply it to the water purification of marine fish tanks.

[0064] The biofilm method includes the following steps:

[0065] S1, prepare biofilm nutrient solution, the components of which are KNO31g / L, KH2PO40.01g / L, and sea salt 30g / L;

[0066] S2, placing the sulfur autotrophic carrier in the biofilm-forming nutrient solution;

[0067] S3, add 15% volume fraction of autotrophic denitrifying bacteria agent to the carrier nutrient solution mixing system, and then place the whole system at 25°C for static culture; the autotrophic denitrifying bacteria agent is a composite bacteria agent prepared by mixing sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 in a mass ratio of 1:2, and the number of live bacteria in the bacterial solution of sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 is ≥10 8 CFU / g.

[0068] S4, regularly check the concentrations of ammonia nitrogen, nitrite, nitrate and total nitrogen in the system, and control the pH of the system at 7.5 throughout the process; when the total nitrogen concentration in the system drops by 80%, add KNO3, and repeat 3 times to determine that the biofilm is complete.

[0069] Example 3

[0070] The sulfur autotrophic carrier of this embodiment includes 30 g of sulfur, 20 g of hydrogen peroxide-modified coral bones, 20 g of pH buffer magnesium carbonate, 1 g of pore-forming agent gypsum, and 5 g of binder sodium silicate.

[0071] The method for preparing a sulfur autotrophic carrier comprises the following steps:

[0072] S1, preparing hydrogen peroxide-modified coral bone: placing coral bone powder in a beaker, adding a hydrogen peroxide solution with a volume concentration of 20% to cover the coral bone powder, and then placing it in a constant temperature water bath, maintaining the temperature at 20°C-30°C, and filtering the reaction solution after sufficient shaking for 8 hours; continuously rinsing the filtered coral bone with tap water to remove the residual hydrogen peroxide solution until the pH of the filtrate is 7, and then drying the hydrogen peroxide-modified coral bone in an oven at 105°C, and then crushing and sieving with a grinder to obtain hydrogen peroxide-modified coral bone with a particle size of 200 mesh.

[0073] S2, pre-treating the raw materials: crushing the sulfur, pH buffer, pore-forming agent and binder respectively to obtain a powder material with a particle size of 200 meshes.

[0074] S3, preparing a binder solution: dissolving a binder sodium silicate in water to prepare a sodium silicate solution with a mass concentration of 30%, then placing the raw materials in step S1 in a mixer, stirring evenly, adding the prepared binder solution, and stirring evenly again;

[0075] S4, the product obtained in step S2 is extruded by a granulator, and then the obtained carrier particles are placed in an oven at 130° C. and dried for 6 hours. After drying, a sulfur autotrophic carrier with a particle size of 3-5 mm is obtained.

[0076] The application of sulfur autotrophic carrier in the water purification of marine fish tanks is to form a biofilm on the sulfur autotrophic carrier and apply it to the water purification of marine fish tanks.

[0077] The biofilm method includes the following steps:

[0078] S1, prepare biofilm nutrient solution, the components of which are KNO30.5g / L, KH2PO40.005g / L, and sea salt 30g / L;

[0079] S2, placing the sulfur autotrophic carrier in the biofilm-forming nutrient solution;

[0080] S3, add 5% volume fraction of autotrophic denitrifying bacteria agent to the carrier nutrient solution mixing system, and then place the whole system at 20°C for static culture; the autotrophic denitrifying bacteria agent is a composite bacteria agent prepared by mixing sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 in a mass ratio of 1:1.5, and the number of live bacteria in the bacterial solution of sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004 is ≥10 8 CFU / g.

[0081] S4, regularly check the concentrations of ammonia nitrogen, nitrite, nitrate and total nitrogen in the system, and control the pH of the system at 7 throughout the process; when the total nitrogen concentration in the system drops by 80%, add KNO3, and repeat 3 times to determine that the biofilm is complete.

[0082] Comparative Example 1

[0083] Compared with Example 1, Comparative Example 1 lacks the hydrogen peroxide-modified coral bone, and the rest of the contents are the same as Example 1.

[0084] Comparative Example 2

[0085] Compared with Example 1, in Comparative Example 2, conventional coral bones were selected and no modification treatment was performed. The rest of the contents were the same as in Example 1.

[0086] Comparative Example 3

[0087] Compared with Example 1, in Comparative Example 3, sodium bicarbonate is selected as the pore-forming agent, and the rest of the contents are the same as in Example 1.

[0088] Comparative Example 4

[0089] Compared with Example 1, in Comparative Example 4, the autotrophic denitrifying bacterial agent is a single sulfur-oxidizing monas SZG-SAD-001, and the rest of the contents are the same as in Example 1.

[0090] The specific surface areas of the sulfur autotrophic carriers prepared in the examples and comparative examples were tested, and the test results are shown in Table 1.

[0091] Table 1 Specific surface area analyzer measurement results

[0092]

[0093]

[0094] After the biofilm formation was completed, the carriers prepared in the examples and comparative examples were placed in an oven at 30°C, and after the moisture on the surface of the carriers was dried, they were put into a simulated seawater fish tank, where the nitrate concentration of the simulated seawater was 80 mg / L and the salinity was 3%. The water quality of the fish tank was observed, and the specific conditions are shown in Tables 2 to 8.

[0095] Table 2 Purification effect of sulfur autotrophic carrier prepared in Example 1 in simulated seawater fish tank

[0096]

[0097] Table 3 Purification effect of sulfur autotrophic carrier prepared in Example 2 in simulated seawater fish tank

[0098]

[0099] Table 4 Purification effect of sulfur autotrophic carrier prepared in Example 3 in simulated seawater fish tank

[0100]

[0101] As shown in Tables 2 to 4, the carriers of Examples 1 to 3 after biofilm formation can start denitrification within 2-3 days after being put into the fish tank, and the nitrate degradation rate on the third day of reaction is 10.1%-11.1%, which is rapid. The carriers of Examples 1 to 3 react in the fish tank for 12 days, and the nitrate degradation rate reaches more than 96.0%. The carrier can control the subsalt concentration at about 0.1 mg / L in the early stage of the application period, and the subsalt concentration is continuously 0 after 3 days of use; and the carrier can control the pH of the fish tank between 6.8 and 8.2 during the application period. The above verification shows that the sulfur autotrophic carrier for water purification of seawater fish tanks provided by the present invention can quickly start denitrification in seawater fish tanks after biofilm formation, and has the performance of continuous denitrification, which has a significant contribution to solving the water quality problem of seawater fish tanks.

[0102] Table 5 Purification effect of sulfur autotrophic carrier prepared in comparative example 1 in simulated seawater fish tank

[0103]

[0104] Table 6 Purification effect of sulfur autotrophic carrier prepared in comparative example 2 in simulated seawater fish tank

[0105]

[0106] Table 7 Purification effect of sulfur autotrophic carrier prepared in comparative example 3 in simulated seawater fish tank

[0107]

[0108] Table 8 Purification effect of sulfur autotrophic carrier prepared in comparative example 4 in simulated seawater fish tank

[0109]

[0110] As shown in Table 5-8, the carriers of Comparative Examples 1-4 after biofilm formation started denitrification slowly after being put into the fish tank. The nitrate degradation rate of Comparative Examples 1-4 on the third day of reaction was only 2.67%-5.94%, which was slower than that of Examples 1-3; the carriers of Comparative Examples 1-4 reacted in the fish tank for 12 days, and the nitrate degradation rate reached 63%-88%, and the degradation rate was significantly slower than that of Examples 1-3; the carrier's salt concentration in the early stage of the application period can be controlled at about 0.1 mg / L, and the salt concentration is continuously 0 after 5-11 days of use; the pH of the carrier in the fish tank during the application period is controlled between 5.1-8.38, and the pH fluctuates greatly. The above verification verifies that the carrier prepared by hydrogen peroxide-modified coral bones, gypsum and composite bacterial agents has the effect of rapidly starting denitrification and continuous denitrification after biofilm formation, which is effective in improving the water quality of seawater fish tanks.

[0111] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A sulfur autotrophic carrier based on seawater fish tank water purification, characterized in that: Calculated by weight, the invention comprises 30-50 parts of sulfur, 20-40 parts of hydrogen peroxide-modified coral bones, 20-40 parts of pH buffer, 1-3 parts of pore-forming agent and 5-10 parts of binder.

2. A sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 1, characterized in that: The preparation method of the hydrogen peroxide modified coral bone is: S1, placing the coral bone powder in a beaker, adding a hydrogen peroxide solution with a volume concentration of 20%-40% to cover the coral bone powder, and then shaking at 20°C-30°C for 8-10 hours and filtering the reaction solution; S2, washing the filtered coral bones with water until the pH value of the filtrate is 7, and then drying the water and crushing and sieving with a grinder to obtain hydrogen peroxide-modified coral bones with a particle size of 100-200 mesh.

3. A sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 1, characterized in that: The pH buffer is one of heavy calcium carbonate, calcium hydroxide, sodium carbonate and magnesium carbonate, the pore-forming agent is gypsum, and the binder is sodium silicate or potassium silicate.

4. A method for preparing a sulfur autotrophic carrier based on seawater fish tank water purification according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, pre-treating the raw materials: crushing and sieving the sulfur, pH buffer, pore-forming agent, and binder respectively to obtain a powder material with a particle size of 100-200 mesh; S2, prepare a binder solution with a mass concentration of 30%-50%, then place the raw materials in step S1 in a mixer, stir evenly, add the prepared binder solution and stir evenly again; S3, the product obtained in step S2 is extruded and formed by a granulator, and then dried to obtain a sulfur autotrophic carrier with a particle size of 3-5 mm.

5. The use of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in any one of claims 1 to 3 in seawater fish tank water purification, characterized in that: The sulfur autotrophic carrier is used to purify the water quality of marine fish tanks after biofilm formation.

6. Application of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 5 in seawater fish tank water purification, characterized in that: The biofilm method includes the following steps: S1, preparing biofilm nutrient solution, the components of which are KNO3, KH2PO4 and sea salt; S2, placing the sulfur autotrophic carrier in the biofilm-forming nutrient solution; S3, adding 5%-15% volume fraction of autotrophic denitrifying bacteria agent to the carrier nutrient solution mixing system, and then placing the entire system at 20°C-30°C for static cultivation; S4, regularly check the concentrations of ammonia nitrogen, nitrite, nitrate and total nitrogen in the system, and control the pH of the system at 7-7.5 throughout the process; when the total nitrogen concentration in the system drops by 80%, add KNO3, and repeat 3 times to determine that the biofilm is complete.

7. The use of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 6 in seawater fish tank water purification, characterized in that: The autotrophic denitrifying bacteria agent is a mixture of sulfur-oxidizing monas SZG-SAD-001 and denitrifying thiobacillus SZG-SAD-004; the deposit number of SZG-SAD-001 is CCTCCNO: M2022806, and the deposit number of SZG-SAD-004 is CCTCCNO: M2023992.

8. Application of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 7 in seawater fish tank water purification, characterized in that: The mass ratio of the sulfur-oxidizing monas SZG-SAD-001 to the denitrifying thiobacillus SZG-SAD-004 is 1:1-2.

9. The use of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 6 in seawater fish tank water purification, characterized in that: The number of viable bacteria in the bacterial solution of Sulfur Oxidizing Mononas SZG-SAD-001 and Thiobacillus Denitrificans SZG-SAD-004 is ≥10 8 CFU / g.

10. The use of a sulfur autotrophic carrier based on seawater fish tank water purification as claimed in claim 6 in seawater fish tank water purification, characterized in that: The contents of the components in the biofilm nutrient solution are: KNO3 0.5-1 g / L, KH2PO4 0.005-0.01 g / L, and sea salt 30 g / L.

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