64 results about "Nitrate reducing" patented technology

The invention belongs to the technical field of building materials, and discloses green microorganism self-repairing concrete and a preparation method thereof.The green microorganism self-repairing concrete is prepared from, by weight, 400 parts of cement, 4-6 parts of modified mesoporous silicon, 60-75 parts of modified stainless steel fibers, 30 parts of nitrate reducing bacteria suspension, 20 parts of microorganism nutrient solution and 700 parts of fine aggregate. The concrete is prepared from the following raw materials in parts by weight: 1400-1500 parts of coarse aggregate, 200 parts of water, 4 parts of a water reducing agent and 1 part of a thickening agent. The microbial self-repairing concrete provided by the invention is relatively high in transmission efficiency of substances among pores, good in repairing effect of internal deep cracks, capable of maintaining long-term self-repairing benefits and wide in application prospect.

The invention discloses a device for recovering ammonium sulfate through electrocatalytic reduction and a using method thereof.The device comprises a wastewater pool and an outer shell, a physical filtering bin is fixedly installed in the outer shell, a water inlet of the physical filtering bin is communicated with the wastewater pool, and a water outlet of the physical filtering bin is fixedly connected with a closed electrolytic tank; the upper end of the closed electrolytic tank is fixedly connected with an electrochemical workstation, the lower end surface of the closed electrolytic tank is fixedly provided with a lead-out port, the lead-out port is fixedly connected with a product recovery device, the product recovery device comprises a first chamber and a second chamber, and a gas diffusion port is formed between the first chamber and the second chamber; a gas diffusion film is fixedly installed in the gas diffusion opening, a product discharging opening is fixedly formed in the second cavity, a product discharging valve is fixedly installed at the product discharging opening, and the nitrate reduction device is simple in structure and convenient to use, and the nitrate reduction efficiency is greatly improved.

The experimental equipment for chemical reduction of nitrate in seawater comprises a storage container, a quantitative disc, a reaction bottle, a stirring mechanism, a sealing opening and closing mechanism and a power pump, according to the experimental equipment, zinc particles stored in the storage container can be quantitatively added into the reaction bottle through the quantitative disc, and seawater is quantitatively injected into the reaction bottle through the power pump; the method comprises the following steps of: adding zinc particles into seawater, stirring the seawater and the zinc particles by using a stirring rod, quantitatively extracting a sample solution obtained after reaction by using a power pump, and automatically cleaning a reaction bottle by using the stirring rod, so that full-automatic operation of the reduction process of the nitrate in the seawater can be realized, the extraction efficiency of chemical reduction of the nitrate in the seawater can be improved, and the operation is simple and convenient. And the consistency of the data after multiple times of extraction is ensured.

The invention relates to the technical field of wastewater treatment, and discloses a method for synergistically strengthening denitrification of an anaerobic ammonia oxidation system based on tea polyphenol and ferric iron, and the method comprises the following steps: in an anaerobic ammonia oxidation reactor, inoculating anaerobic ammonia oxidation sludge, adding wastewater, adding tea polyphenol-Fe < 3 + >, and treating the wastewater. According to the invention, the tea polyphenol can promote the anaerobic ammonium oxidation bacteria to absorb ferric iron and enhance the biological utilization of iron element in the anaerobic ammonium oxidation system. Iron elements absorbed by the anaerobic ammonium oxidation bacteria can be used for synthesizing key functional enzymes, the metabolic activity of anaerobic ammonium oxidation and dissimilatory nitrate reduction into ammonium of the anaerobic ammonium oxidation bacteria is enhanced, meanwhile, coupling of two nitrogen conversion ways is promoted, the total nitrogen removal rate is synergistically increased, and the denitrification efficiency of an anaerobic ammonium oxidation system is enhanced.

The utility model belongs to the technical field of biological denitrification of industrial aquaculture water, and particularly relates to a denitrification device suitable for an industrial aquaculture system. Comprising an aerobic nitrification zone, a carbon source zone, an aerobic denitrification zone and a suspended particle removal zone which are communicated in sequence, a filter material is arranged in the aerobic nitrification zone, and the aerobic nitrification zone is used for carrying out biological oxidation on aquaculture water to generate nitrate; the upper part of the carbon source region is filled with carbon sources; the aerobic denitrification area is used for reducing nitrate in the water body into nitrogen; the suspended particle removal area is used for removing suspended particles in the water body. A water inlet pipe is arranged at the bottom of one side wall of the aerobic nitrification area, an aerobic nitrification area overflow port is formed in the upper part of the other side wall of the aerobic nitrification area, and the internal space of the aerobic nitrification area is distributed in a shape; a water outlet pipe is arranged at the bottom of the side wall of the suspended particle removal area. According to the device, aerobic nitrification, aerobic denitrification and suspended particulate matter removal are organically integrated, intensification and modularization are realized, the device is simple in structure and convenient to operate, and the culture denitrification effect is effectively improved.

The invention discloses a bacterial strain for reducing dissimilatory nitrate into ammonia nitrogen through anaerobic biodegradation of polycyclic aromatic hydrocarbon and application of the bacterial strain, the bacterial strain is named as PheICNA, and the bacterial strain belongs to Intraporum calvum. The strain is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation number is CGMCC No.40686. The strain can degrade polycyclic aromatic hydrocarbons such as phenanthrene under anaerobic conditions and completely metabolize the polycyclic aromatic hydrocarbons into carbon dioxide. Meanwhile, nitrate radicals are reduced into ammonium nitrogen, and the generated ammonium nitrogen can be used for growth of microorganisms and can be used as a nitrogen source for plants. The strain can be used for biologically repairing polycyclic aromatic hydrocarbon pollutants such as phenanthrene in soil, can convert nitrate nitrogen in the soil into ammoniacal nitrogen at the same time, achieves the effect of nitrogen maintenance, and has good application prospects in the aspects of polluted soil treatment and the like.

The invention discloses a sewage treatment equipment state supervision system, belongs to the technical field of sewage treatment, and solves the problems that the sewage contains reducing sulfides and competes with denitrifying bacteria for electron donors, so that the COD in an anoxic zone is sufficient, the nitrate reduction rate is low, a false carbon source sufficient trap with inhibited denitrification occurs, but the sulfide is easy to oxidize, and the potential safety hazard is caused. And a sampling detection result is distorted and is difficult to identify. According to the invention, sewage is measured in an anoxic zone through a probe interface module, under the scheduling of a time division control module, a constant potential rectifier module excites sulfide characteristic oxidation current in a DPV time period, a logarithmic current detection module captures a peak value and integrates a charge quantity, an impedance detection module measures phase offset in an EIS time period, a signal processing module fuses characteristic values, and a temperature compensation module eliminates errors. The reference electrode protection module ensures signal fidelity, outputs sulfide concentration and electron competition index, starts a dosing system when the concentration exceeds the limit, and prevents sampling oxidation distortion in the whole process.

The invention belongs to the technical field of microbial fermentation, and relates to a nitrate reducing pseudomonas capable of biologically converting limonene, which is preserved in the China Center for Culture Collection, the classification name of which is Pseudomonas nitritiducens GJ-01, the preservation number of which is CCTCC M 20251439, and the preservation date of which is June 23, 2025, and the preservation number of which is CCTCC M 20251439. According to the invention, the nitrate reducing pseudomonas strain with efficient conversion capability and capable of biologically converting limonene is separated and screened, so that a new strain resource is provided for microbial conversion of D-limonene, and a theoretical basis is provided for biosynthesis and metabolic engineering modification of terpenoids; therefore, the method has a wide application prospect in the field of microbial fermentation.

The invention belongs to the technical field of soil improvement, and particularly relates to a modified porous composite material as well as a preparation method and application thereof. The composite material comprises modified ceramsite and microorganisms, the modified ceramsite comprises a ceramsite matrix and a calcium alginate gel layer; the ceramsite matrix has a porous structure; the calcium alginate gel layer is loaded on the surface and the interior of the ceramsite matrix, and the surface and the interior of the ceramsite matrix and the interior of the calcium alginate gel layer are coated with microorganisms by the calcium alginate gel layer. The composite material with a specific structure can improve microbial activity, has an obvious promotion effect on ferrous oxidation, and can effectively avoid degradation of organic carbon in soil, so that a stable carbon sequestration effect is achieved; meanwhile, generation of nitrous oxide in the process of iron-oxidizing bacterium ferrous oxidation coupling nitrate reduction can be effectively inhibited, greenhouse gas emission in the process of iron-oxidizing bacterium nitrate reduction coupling ferrous oxidation is reduced, the DOC concentration is reduced, and good carbon sequestration and emission reduction effects are achieved.

The invention relates to nitrate reduction pelagic bacteria and application thereof. The nitrate reductive ocean bacillus can be fermented to produce pyrroloquinoline quinone (PQQ) and trichothecenes toxin degrading enzyme, the trichothecenes toxin degrading enzyme mainly exists in bacterial cell lysis buffer, and the degradation rate of the trichothecenes toxin degrading enzyme to vomitoxin is 83%. The bacterial strain fermentation liquor can be used for degrading 39.3 percent of nivalenol and 100 percent of 15-acetyl deoxynivalenol. The strain or the trichothecene toxin degrading enzyme produced by the strain can be used for complete feed, concentrated feed, premixed feed, feed raw materials such as grain, corn, peanut meal, wheat and oat, silage, grain, grain and oil, grain processing and agricultural and sideline products, aged grain, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour, corn flour and corn flour. Through biodegradation of industrial ethanol processing byproducts and trichothecenes in food, the quality safety of feed and food can be improved.

The invention relates to zero-valent foam iron loaded with 5% of copper, a preparation method of the zero-valent foam iron and a system and method for preparing ammonia through nitrate reduction, the zero-valent foam iron loaded with 5% of copper is prepared by placing foam iron in a copper chloride solution and carrying out ultrasonic treatment, and copper is uniformly loaded on the surface of the foam iron in a cluster form. The system for reducing the nitrate to prepare the ammonia comprises a high-frequency alternating magnetic field induction heater, an induction heating coil, a condensate water tank for storing condensate water, a mechanical pump for conveying the condensate water, a mechanical stirrer and a three-opening high borosilicate glass reactor. The method for preparing ammonia through nitrate reduction comprises the following steps: electrifying a nitrate solution and zero-valent foam iron loaded with 5% of copper in a reactor, and then carrying out a nitrate reduction ammonia preparation reaction. According to the method, the high-frequency alternating magnetic field is used for accelerating the nitrate reduction rate of the iron-based bimetallic material, the path of a reduction product is controlled, and the resource utilization capacity of pickling wastewater in the metal processing industry is enhanced.

The utility model provides a sewage treatment device based on a UASB (Upflow Anaerobic Sludge Blanket) process, which relates to sewage treatment equipment and comprises a tank body, a reaction area, an electric biological treatment area and a settling area are sequentially arranged from the bottom to the top of the tank body, and the reaction area is communicated with the settling area through the electric biological treatment area; a granular sludge bed is arranged in the reaction area; the electro-biological treatment area is provided with a first electrode and a second electrode, and the first electrode and the second electrode are connected with a variable-frequency power supply through wires; periodically reversing the variable-frequency power supply; a water inlet pipe is arranged at the bottom of the tank body and is communicated with the reaction area; a water outlet pipe is arranged at the top of the tank body and is communicated with the settling area. Organic matters are decomposed through microorganisms on the granular sludge bed and converted into biogas, and an alternating-current electric field is generated through the first electrode, the second electrode and the variable-frequency power supply; in the electro-biological treatment area, denitrifying bacteria utilize organic matters as electron donors to reduce nitrate into nitrogen, so that denitrification is realized; meanwhile, the bacteria with the phosphorus removal function absorb and release phosphorus under the action of the electric field, and phosphorus removal is achieved.

The application provides an electrochemical synthesis method of glycine, improves catalytic activity of nitrate reduction and C-N coupling process through atom-dispersed Co-N active sites, and improves mass transfer efficiency through ordered mesoporous structure, thereby relieving the problem of limited substrate diffusion in the reaction process, so that higher glycine Faraday efficiency and yield can be obtained; through taking cobalt acetate tetrahydrate, 1,10-phenanthroline and magnesium hydroxide as raw materials, and sequentially performing reflux coordination, high-temperature pyrolysis and acid washing template treatment, uniform anchoring and atomic-level dispersion of cobalt species in the carbon skeleton can be realized, agglomeration of cobalt particles in the heat treatment process is avoided, and therefore the utilization rate and catalytic activity of cobalt active sites are significantly improved. Meanwhile, the magnesium hydroxide as a template material is removed in the subsequent acid washing process, and rich mesoporous structure can be formed in the catalyst, which is beneficial to rapid diffusion and mass transfer of reactants, intermediates and products, and diffusion limitation in the reaction process is relieved.

The invention discloses a staphylococcus mimicus SMP6, a microbial agent and application of the staphylococcus mimicus SMP6 and the microbial agent, and belongs to the technical field of microbial food fermentation, and the preservation number of the staphylococcus mimicus SMP6 is CGMCC (China General Microbiological Culture Collection Center) NO.34714. The strain is high in safety, good in salt resistance, acid resistance and nitrite resistance, good in amino acid decarboxylation capacity and nitrate reduction capacity, low in arginine ammonia production capacity and high in extracellular protease activity and extracellular lipase activity, meanwhile, the sausage fat oxidation level can be effectively inhibited when the strain is used for preparing the fermented sausage, and the sausage quality is improved. The fermented product has better appearance, color, fragrance, taste and viscoelasticity indexes.

The invention discloses an inhibiting bacterium for inhibiting sulfate reducing bacteria and anti-corrosion application thereof, and belongs to the field of microbial anti-corrosion technology and application of oilfield reinjection water, the inhibiting bacterium is bacillus licheniformis NRB-12, and the preservation number is CGMCC (China General Microbiological Culture Collection Center) No. 24531. The bacillus licheniformis disclosed by the invention is used for treating oilfield reinjection water with high sulfate reducing bacteria content, and has the characteristics of environment friendliness, low price, large treatment range and simplicity in operation; effective inhibition of sulfate reducing bacteria is achieved by providing a nutrient system optimized by nitrate reducing bacteria, and safe production of oil fields and oil extraction is achieved.

The invention discloses a self-purification prediction simulation method for a petroleum hydrocarbon polluted site under soil-water interaction based on COMSOL Multiphysics, and the method comprises the steps: obtaining historical meteorological data, and constructing a rainfall flux simulation process through a function; taking the rainfall flux as an upper boundary source item for driving the three-phase fluid to move, and constructing a three-phase fluid motion model; simulating and predicting a migration path and a phase transformation process of the dissolved phase petroleum hydrocarbon in a water phase; constructing a migration path of an electron acceptor and a migration path of gas-phase oxygen, establishing a degradation kinetic model of each path, calculating a total biodegradation flux through aerobic degradation, nitrate reduction degradation and sulfate reduction degradation, and correcting the degradation kinetic models of the paths by using correction factors; biodegradation flux and a three-phase fluid motion model are coupled, rainfall flux is constructed through a piecewise function and annual rainfall data and is directly associated to core parameter soil water phase pressure, and the physical consistency of a driving mechanism is enhanced.

The invention relates to a synchronous nitrogen and phosphorus removal sewage treatment method based on secondary calcification modified siderite coupled sulfur autotrophic denitrification. According to the method, active sites and buffer capacity of siderite are improved by using calcination and calcium-based modification processes, nitrate reduction is driven by sulfur autotrophic denitrifying flora, and phosphate is fixed by using a synergistic precipitation effect of iron and calcium ions. According to the system, a neutral pH environment is effectively maintained, inhibition of acidification on microbial activity is avoided, generation of intermediate products is reduced, the denitrification efficiency is remarkably improved, efficient phosphorus removal is synchronously realized, and meanwhile, a reactor with a novel structure is adopted, so that filler hardening can be effectively prevented, and a supporting effect is achieved. The sewage treatment method adopted by the invention does not need additional carbon sources or chemical agents, is high in process integration level, is suitable for treatment of decentralized sewage, industrial wastewater and eutrophic water bodies, and has the advantages of low operation cost, environmental friendliness, easiness in engineering and the like.

This application relates to a method and its application for reducing nitrate nitrogen to ammonia nitrogen in wastewater using a dual-bacterial inoculant. The method involves separately expanding, washing, and resuspending electron-donating bacteria and dissimilatory nitrate-reducing ammonium-producing bacteria, then mixing them in a co-culture medium to form a dual-bacterial inoculant; introducing the co-culture medium containing the dual-bacterial inoculant into the wastewater to be treated, and reducing nitrate nitrogen to ammonia nitrogen in the wastewater under anaerobic conditions. This method can reduce nitrate nitrogen in wastewater into a high-energy-density energy storage substance, and can also alleviate the problems of low utilization rate of ammonium nitrogen fertilizer and non-point source pollution, which is of great value for nitrogen pollution control and green sustainable agricultural development.

The invention belongs to the technical field of environmental treatment, and particularly relates to a wastewater treatment system and a method for treating kitchen waste water. The sludge subjected to anaerobic fermentation modification in the sludge modification tank is used for adsorbing grease in the kitchen waste water, so that the grease removal rate is increased; effluent of the anoxic tank flows back to the anaerobic tank, sulfide generated by protein decomposition in the anaerobic tank is oxidized into sulfate, and the emission of malodorous gas is reduced; partial nitrate is reduced into nitrite through short-cut denitrification of the anoxic tank, and a substrate is continuously provided for anaerobic ammonia oxidation; and the total nitrogen removal rate is improved on the premise of not additionally adding a carbon source. The anaerobic tank is inoculated with hydrolytic acidification bacteria, refractory organic matters are hydrolyzed into biodegradable organic matters, denitrifying bacteria utilize the biodegradable organic matters to convert nitrite / nitrate into nitrogen, and phosphorus-accumulating bacteria synchronously complete anaerobic phosphorus release; and the aerobic tank uses nitrite / nitrate of the effluent of the anoxic tank as an oxidizing agent to promote phosphorus-accumulating bacteria to absorb phosphorus so as to realize phosphorus removal.

This invention discloses a ruthenium complex-modified nickel-based metal framework material, its preparation method, and its application in the electrocatalytic reduction of nitrate to ammonia. The method includes: adding a DMAC solution of terephthalic acid to an aqueous nickel chloride solution, mixing, adding the ruthenium complex, transferring the resulting solution to an autoclave for solvothermal treatment, immersing the resulting precipitate in an aqueous ammonium hexafluorophosphate solution, and stirring at room temperature to obtain RuNi-BDC. The introduction of the ruthenium complex, through the interaction between its organic ligands and the MOF framework, achieves high dispersion of ruthenium species, increases the exposure of active sites, and enhances the structural stability of the material. This system optimizes the adsorption energy for reaction intermediates, transforming the catalytic mechanism from single Ni catalysis to Ni-Ru bimetallic synergistic catalysis, effectively lowering the energy barrier of the rate-determining step of nitrate reduction, and improving the activity of the electrocatalytic nitrate reduction reaction, providing a new approach for achieving efficient electrocatalytic reduction of nitrate to ammonia.

The invention belongs to the technical field of water pollution control, and particularly relates to an ammonia direct oxidation denitrification system and method for nitrate-containing sewage, the method comprises the following steps: S1, in an anoxic AMAO denitrification reactor, acetone is added into the ammonia nitrogen and nitrate-containing sewage, AMAO functional microorganisms take acetone as a mediator and take nitrate as an electron acceptor, and the ammonia nitrogen and nitrate-containing sewage is subjected to denitrification treatment; ammonia nitrogen is oxidized, nitrate is reduced, and nitrogen is generated synchronously; s2, the effluent in the step S1 enters an aerobic AMAO deep denitrification reactor, residual acetone is utilized to further oxidize residual ammonia nitrogen through an AMAO reaction under the aerobic condition, and deep denitrification is achieved. According to the method, the same core metabolic pathway is utilized, the nitrate and ammonia nitrogen removal problem is sequentially solved through environmental regulation and control, the process is compact, operation is easy and convenient, the treatment efficiency of the compound nitrogen polluted wastewater is remarkably improved, the total nitrogen removal rate can reach 95% or above, the total nitrogen of effluent is stably lower than 2 mg / L, the deep nitrogen removal effect is remarkable, and the method is suitable for industrial production. And the risk of nitrate residue or secondary pollution in the traditional process is thoroughly avoided.

The invention discloses a preparation method and application of a CdS / COF heterojunction photocatalytic material for ammonia production through nitrate reduction, relates to a preparation method and application of a photocatalyst, and aims to solve the problem that the efficiency of ammonia production through nitrate reduction of a COF photocatalyst or a COF / CdS heterojunction catalyst is low. The method comprises the following steps: preparing COF powder from 1, 3, 5-tris (4-aminophenyl) benzene and 1, 3, 5-benzenetricarboxaldehyde; the preparation method comprises the following steps: preparing a CdS / COF heterojunction photocatalytic material, uniformly coating the outer surface of COF with CdS by adopting an in-situ growth mode to obtain the CdS / COF heterojunction photocatalytic material, applying the CdS / COF heterojunction photocatalytic material to photocatalytic reduction of nitrate to produce ammonia, under the irradiation of an AM 1.5 lamp and under the condition of not adding any sacrificial reagent, the NH4 < + > yield reaches 138.21 micromoles g <-1 > h <-1 > and is improved by 3.04 and 2.39 times compared with pure CdS and COF, and the CdS / COF heterojunction photocatalytic material can be applied to the field of photocatalytic reduction of nitrate to produce ammonia.

The invention relates to a bacteria-resistant hydrogel profile control agent as well as a preparation method and application thereof. The antibacterial hydrogel profile control agent is prepared from the following components in percentage by weight: 0.10 to 0.50 percent of polymer, 0.10 to 1.00 percent of organic resin, 0.10 to 0.60 percent of cross-linking agent, 0.01 to 0.30 percent of conditioning agent, 0.05 to 0.30 percent of bacteriostatic agent and the balance of oilfield injection water. According to the antibacterial hydrogel profile control agent provided by the invention, a polymer and water-soluble phenolic resin are used as main structures of a gel network, organic chromium is used as a cross-linking agent, oxalic acid or ammonium chloride is used as a regulator, and sodium nitrite is used as a bacteriostatic agent; by promoting the reproduction of nitrate reducing bacteria in water, the growth of sulfate reducing bacteria, saprophytic bacteria and iron bacteria is inhibited, the influence of strains on a gel system is reduced, and the gel has controllable gel forming time and strength, excellent bacteria resistance and long-term stability.

The present invention belongs to the field of sewage treatment technology, and specifically relates to a method for improving sewage treatment efficiency under ciprofloxacin stress. The method involves adding polyamide to sewage containing ciprofloxacin, followed by aerobic denitrification treatment. Experiments have shown that while ciprofloxacin can severely inhibit sludge performance and affect the metabolic activity of aerobic denitrifying bacteria, polyamide can significantly mitigate the effects of ciprofloxacin on aerobic denitrifying bacteria under short-term and long-term stress, promoting the denitrification metabolic process, enhancing nitrate reduction, and improving the aerobic denitrification treatment efficiency of sewage.

This invention discloses a method for treating nitrogen-containing wastewater based on nitrate dissimilatory reduction combined with sulfur autotrophic denitrification coupled with anaerobic ammonia oxidation, belonging to the field of wastewater microbial treatment technology. It employs a coupling of nitrate dissimilatory reduction to ammonium, sulfur autotrophic denitrification, and anaerobic ammonia oxidation. The anaerobic ammonia oxidation reaction requires the supply of nitrite and ammonia nitrogen, while nitrate dissimilatory reduction (DNRA) can produce ammonia nitrogen, and sulfur autotrophic denitrification can accumulate nitrite nitrogen. Furthermore, the three processes require similar environmental conditions, and the substrate and products can complement each other well. Under anaerobic conditions, DNRA bacteria reduce nitrate to ammonia nitrogen, and sulfur autotrophic denitrifying bacteria reduce nitrate to nitrite. By controlling the ratio between sulfide and nitrate nitrogen (i.e., the sulfur-nitrogen molar ratio), the reaction type is guided, ensuring that the products are ammonia nitrogen and nitrite. Then, the anaerobic ammonia oxidation reaction occurs, achieving simultaneous removal of ammonia nitrogen and nitrite nitrogen. This method can increase the removal rate and removal load of ammonia nitrogen in wastewater.

The invention discloses a high-ammonia-nitrogen wastewater treatment method, and belongs to the field of water treatment. The method comprises the following steps: firstly, carrying out FeCl2 solution activation on a Fe0 + SiO2 core-shell structure vertical suspension carrier, then adding magnetic nanoparticles in an anaerobic ammonium oxidation zone, applying an external magnetic field, guiding anaerobic ammonium oxidation bacteria to be enriched on the surface of the carrier, domesticating at 15 DEG C, and inducing to form a high-coverage biological membrane. The system adopts a partition coupling design: a partial ammonia nitrogen is converted into nitrite by a short-cut nitrification tank; in the short-cut denitrification zone, organic matters in raw water are utilized to reduce residual nitrate in the system into nitrite; and in the anaerobic ammonia oxidation zone, ammonia nitrogen and the nitrite provided in the previous step are used for denitrification. By intelligently controlling internal reflux, the by-product nitrate of anaerobic ammonia oxidation is converted into nitrite for reuse, and internal circulation of nitrogen is formed. The method solves the problems of slow growth and easy loss of anaerobic ammonium oxidation bacteria, by-product nitrate accumulation, low-temperature activity inhibition and the like, and significantly improves the denitrification efficiency and stability of the system.

The invention relates to an enrichment method of anaerobic nitrate reduction microorganisms and application thereof, and belongs to the technical field of microorganisms. According to the enrichment method disclosed by the invention, active cells in a solid sample are extracted by utilizing a Nycodenz density gradient centrifugation method, and then the active cells are inoculated into an anaerobic nitrate culture medium to carry out directional enrichment on anaerobic nitrate reducing microorganisms. According to the method, active cells can be efficiently enriched, the influence of a matrix is effectively reduced, and meanwhile, compared with a conventional cell enrichment technology, the efficiency is higher, and the cost is lower.

The present invention belongs to the field of electrocatalysis, relates to nitrate reduction, particularly to the synthesis of ammonia by nitrate reduction in acidic media, and discloses a one-dimensional nitride-doped Ag / WO3 nanorod electrocatalyst, its preparation method and application. For the first time, a stable one-dimensional nitride-doped WO3 nanorod is synthesized in this application, and Ag species with poor hydrogen evolution activity are decorated on it for rapidly reducing nitrate to ammonia under acidic conditions. This catalyst improves the adsorption of nitrate, reduces the energy barrier of the rate-determining step, thereby greatly improving the efficiency of ammonia synthesis and reducing HER at the amperometric current density. This work provides in-depth insights into acidic nitrate reduction in ammonia electrosynthesis and develops corrosion-resistant electrocatalysts for energy conversion.

The invention discloses a preparation method and application of a BiOCOOH-A-Fe photocatalyst, and the specific preparation process is as follows: pre-prepared BiOCOOH is taken as a carrier, iron monoatoms are stably anchored on the surface of the BiOCOOH through the axial coordination effect of APTES, the APTES can realize firm loading of the iron monoatoms by the BiOCOOH, so that the prepared composite photocatalyst has better stability and catalytic activity, and the prepared composite photocatalyst has good application prospects. Meanwhile, a-NH2 terminal group which does not participate in coordination in the APTES can obviously enhance the adsorption of NO3 <->, so that the selectivity of nitrogen in the process of photocatalytic reduction of nitrate by the composite catalyst can be improved. The composite photocatalyst has the advantages of wide light response range, high quantum efficiency and the like, nitrate in a water body can be efficiently and rapidly reduced into nitrogen under the illumination condition, and the composite photocatalyst has good stability, can be recycled for multiple times and is an ideal water treatment photocatalyst.

The invention belongs to the field of environmental engineering and wastewater biological treatment, and particularly relates to an efficient denitrification method based on a VFA-sucrose mixed carbon source and application of the efficient denitrification method. Activated sludge is inoculated in a denitrification device, VFA-cane sugar is used as an external carbon source, a domesticated denitrification microbial system is obtained through periodic modes of water inlet, anoxic reaction, precipitation, drainage and the like, and the system selectively enriches functional bacteria such as bacteroides, geomonas and competitive bacillus. The gene abundance of a substrate transport system (ABC transporter) and a fatty acid metabolic pathway in a microbial community is remarkably enhanced, the nitrate reduction rate is remarkably improved, and the nitrite accumulation amount is controlled at an extremely low level lt; the COD (Chemical Oxygen Demand) removal rate is more than 95%, and the method is particularly suitable for deep denitrification treatment of wastewater.