Method for shortcut nitrification of ammonia-nitrogen wastewater and application

Abstract

The invention relates to the technical field of biological sewage treatment, and provides an ammonia-nitrogen wastewater shortcut nitrification method and application. The method comprises the following steps: S100, inoculating mature autotrophic short-cut nitrification sludge into a reactor to obtain a first mixed solution; s200, conveying water containing ammonia salt, bicarbonate and phosphate into the reactor through a water inlet pump; s300, mixing the first mixed solution with water through a stirrer, and carrying out an aeration reaction to obtain a second mixed solution; s400, stirring of the second mixed solution is stopped, aeration and pH control are carried out, solid-liquid separation is carried out, and treated water and sludge are obtained; s500, starting a water outlet pump, and uniformly discharging the treated water; and S600, the steps S200 to S500 are repeated, a cerium chloride solution is added, and long-term operation is carried out. According to the method, low-concentration cerium is used for selectively enriching endogenous heterotrophic nitrite bacteria, and cerium ions and autotrophic nitrite bacteria work cooperatively, so that the accumulation rate of nitrite is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of biological sewage treatment, and in particular to a method and application of short-range nitrification of ammonia nitrogen wastewater. Background Art

[0002] Cerium is the rare earth element with the highest content in the world's soil and the main component of ionic rare earth mining tailings. Due to its unique redox properties, cerium is widely used in pigments, catalysts, ceramics, alloys, optics, coatings and medical fields. In addition, cerium is used as a safe and economical feed additive to replace antibiotics to promote poultry growth and increase egg production.

[0003] With the development of social economy, the discharge of low C / N ratio ammonia nitrogen wastewater such as aquaculture wastewater, domestic sewage and landfill leachate has been increasing. Nitrification-denitrification process is a commonly used treatment method, but due to the rapid consumption of organic carbon source and high aeration energy consumption, the operating cost is relatively high. In contrast, the short-range nitrification / anaerobic ammonium oxidation (Anammox) process, as a new autotrophic nitrogen removal technology, has the advantages of low energy consumption, no need for external organic carbon source, significantly lower cost, and can stably provide nitrite, thus supporting the implementation of PN / Anammox process.

[0004] However, in the long-term operation of the short-range nitrification process, due to the accumulation of extracellular polymers, problems such as nitrogen loss, nitrite reduction and N2O emission are prone to occur. N2O is a strong greenhouse gas, and its greenhouse effect is much higher than that of carbon dioxide and methane. In addition, the reduction of nitrite means that more oxygen is needed to oxidize ammonia nitrogen, thereby increasing aeration energy consumption. In the PN process, the decomposition products of extracellular polymers are mainly propionic acid-type small molecular organic matter, which is not conducive to the accumulation of nitrite by heterotrophic nitrosating bacteria.

[0005] Therefore, there is an urgent need for a technical method that can improve the processing capacity of the short-range nitrification process while maintaining low energy consumption and low cost. Summary of the invention

[0006] The present invention provides a method and application of short-range nitrification of ammonia nitrogen wastewater, and for the first time proposes to use low-concentration cerium to selectively enrich endogenous heterotrophic nitrosating bacteria, and to cooperate with autotrophic nitrosating bacteria through cerium ions, thereby increasing the accumulation rate of nitrite; and by regulating the metabolic type of endogenous organic matter, the close cooperation between autotrophic nitrosating bacteria and endogenous heterotrophic nitrosating bacteria is promoted, the synergistic effect of autotrophic and heterotrophic nitrosating bacteria is achieved, and the inherent rate limitation of autotrophic nitrosating bacteria is broken through.

[0007] In order to solve the above problems, the present invention provides a method for short-term nitrification of ammonia nitrogen wastewater, which comprises: S100, inoculation: inoculating mature autotrophic short-term nitrification sludge into a reactor to obtain a first mixed solution; S200, water inlet: conveying water containing ammonium salts, bicarbonates and phosphates to the reactor through a water inlet pump; S300, stirring and aeration: mixing the first mixed solution in the reactor with water containing ammonium salts, bicarbonates and phosphates through a stirrer, and performing an aeration reaction to obtain a second mixed solution; S400, standing and separation: stopping stirring, aeration and pH control of the second mixed solution, performing solid-liquid separation, and obtaining treated water and sludge; S500, water outlet: activating the water outlet pump to evenly discharge the treated water; S600, operation: repeating steps S200-S500 for long-term operation; wherein, step S600 also includes: adding cerium chloride solution and continuously operating.

[0008] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the present invention proposes for the first time to use cerium to selectively enrich endogenous heterotrophic nitrosating bacteria, and the synergistic effect of cerium ions and autotrophic nitrosating bacteria can significantly improve the accumulation rate and yield of nitrite, and at the same time solve the problems of high greenhouse gas emissions and nitrogen loss in traditional methods, and achieve significant environmental benefits. By controlling the cerium concentration, the emission of greenhouse gases such as N2O is reduced; and by regulating the metabolic type of endogenous organic matter, the close cooperation between autotrophic nitrosating bacteria and endogenous heterotrophic nitrosating bacteria is promoted, the synergistic effect of autotrophic and heterotrophic nitrosating bacteria is achieved, and the inherent rate limitation of autotrophic nitrosating bacteria is broken through. Compared with the traditional nitrification and denitrification process, the present invention does not require an external organic carbon source, and the aeration energy consumption is low, and a higher nitrification efficiency can still be achieved.

[0009] In a technical solution of the present invention, step S600 specifically includes: S601, repeating steps S200-S500, and running for 20 days; S602, adding cerium chloride solution on the basis of step S601, and running for 20 days.

[0010] Compared with the prior art, the technical effects achieved by adopting the technical solution are as follows: by repeating the operations of steps S200 to S500 in step S601, the long-term stability of the system is verified, and the repeated reaction process ensures that the ammonia nitrogen wastewater treatment system can continuously and efficiently remove ammonia nitrogen without performance degradation; and continuous operation for 20 days can fully optimize the reaction conditions and the stability of the microbial community, ensuring that the microorganisms in the reactor can adapt to the changing factors in the wastewater, thereby maximizing the treatment effect; long-term operation ensures that the autotrophic nitrite bacteria and heterotrophic nitrite bacteria in the reactor can fully adapt and work together, thereby ensuring the continuity and efficiency of the treatment process; finally, through repeated operation, the effect of ammonia nitrogen removal and the accumulation of nitrite can be systematically monitored, thereby providing data support for further optimization of the process;

[0011] In step S602, by adding cerium chloride solution, the treatment effect is further improved on the basis of maintaining stable operation of the reactor, and it has strong flexibility and adaptability. Cerium ions can promote the enrichment of endogenous heterotrophic nitrite bacteria, and synergize with autotrophic nitrite bacteria to further increase the accumulation rate and conversion efficiency of nitrite, thereby improving the rate of wastewater treatment, especially under conditions of low ammonia nitrogen concentration; in addition, since the addition of cerium chloride can optimize the metabolic activities of microorganisms, especially enhance the cooperation ability of autotrophic and heterotrophic bacteria, the overall nitrogen removal effect is improved, the residual amount of ammonia nitrogen can be effectively reduced, and the stability of the treated water quality is improved; the addition of cerium ions not only enhances the nitrification reaction, but also reduces the emission of greenhouse gases, which has a positive effect on environmental protection, especially in the long-term operation process, it reduces the greenhouse gases generated in the nitrogen conversion process.

[0012] In one technical solution of the present invention, the concentration of the cerium chloride solution is 0.05-2.5 mg / L.

[0013] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: cerium chloride, as a redox catalyst, can promote the nitrification reaction of microorganisms in the process of ammonia nitrogen conversion. Under the action of cerium chloride, the rate of nitrification reaction is significantly improved, especially the rate of nitrite generation is enhanced, thereby improving the short-range nitrification effect of the system; cerium has a promoting effect on autotrophic and heterotrophic nitrosating bacteria, especially in the process of microbial treatment of ammonia nitrogen, cerium ions can enhance the metabolic activity of microorganisms by regulating the redox environment, and can more effectively convert ammonia nitrogen into nitrite, thereby improving the nitrogen removal efficiency; cerium ions can promote the synergistic effect of autotrophic nitrosating bacteria and heterotrophic nitrosating bacteria, enhance the accumulation of nitrite, thereby The residual concentration of ammonia nitrogen is reduced, and the treatment effect is further optimized. Greenhouse gases are produced during the nitrification reaction, and the concentration of cerium chloride is set in the range of 0.05-2.5 mg / L, which helps to ensure efficient removal of ammonia nitrogen while reducing the emission of greenhouse gases such as nitrogen oxides, thereby improving environmental friendliness. At appropriate concentrations, cerium chloride can also enhance the stability of the microbial community in the system, making the microbial community more stable, and can continuously and efficiently convert ammonia nitrogen during long-term operation, thereby enhancing the long-term stability and reliability of the system. Finally, the concentration of cerium chloride is only 0.05-2.5 mg / L. Low concentrations of cerium will not cause secondary pollution to the environment, and can significantly improve the wastewater treatment effect, with good environmental benefits.

[0014] In a technical solution of the present invention, in step S100: the reactor is a sequencing batch reactor; and / or the effective volume of the reactor is 4L; and / or the effluent exchange ratio of the reactor is 50%; and / or the volume of the autotrophic short-range nitrification sludge accounts for 3%-5% of the effective volume of the reactor; and / or the concentration of volatile suspended solids in the first mixed liquor is 1500-2200mgVSS / L.

[0015] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the sequencing batch reactor adopts batch reaction and periodic operation, and through switching of multiple stages, effectively controls the nitrification process of ammonia nitrogen, ensures the optimization of conditions such as oxygen supply, reaction time and sludge sedimentation, and promotes the smooth progress of the nitrification process; the effective volume of the reactor is 4L, which determines the reactor processing capacity, sludge retention time and reaction time of ammonia nitrogen wastewater. Under the effective volume of 4L, sufficient reaction time can be ensured so that the short-range nitrification process can proceed smoothly; the effluent exchange ratio of the reactor is 50%, which means that after each cycle, 50% of the water in the reactor is discharged and exchanged with new water. The effluent exchange ratio of 50% can ensure that fresh water is continuously added to help keep the reactant concentration and sludge concentration in the reactor within an appropriate range, and regular drainage and water replenishment can avoid Avoid excessive sludge accumulation and prevent excessive concentration in the reactor from inhibiting the activity of microorganisms; the proportion of autotrophic short-term nitrification sludge in the effective volume of the reactor is 3%-5%, ensuring that there are sufficient numbers of nitrifying bacteria in the reactor to meet the treatment needs of ammonia nitrogen wastewater, and appropriate sludge concentration can improve the conversion efficiency of ammonia nitrogen, ensure the smooth progress of nitrite reaction, and avoid the influence of too little or too much sludge on reaction efficiency; the volatile suspended solids (VSS) concentration in the first mixed liquor is 1500-2200 mgVSS / L, VSS represents the number of active microorganisms in the reactor and their metabolic activity, and a moderate VSS concentration helps to ensure sufficient microbial mass for short-term nitrification reaction, especially the activity of autotrophic nitrite bacteria and heterotrophic bacteria, and can also enhance the adaptability and stability of microorganisms, and reduce the reduction in reaction efficiency caused by sludge aging.

[0016] In a technical solution of the present invention, in step S100: the abundance of Nitrosomonas in the mature autotrophic short-term nitrification sludge is greater than 40%; and / or the mature autotrophic short-term nitrification sludge includes at least one of extracellular polymers, denitrifying bacteria, and anaerobic bacteria.

[0017] Compared with the prior art, the technical effects achieved by the technical solution are as follows: Nitrosomonas is the key bacterial species that oxidizes ammonia nitrogen into nitrite in the short-range nitrification process. In mature autotrophic short-range nitrification sludge, the abundance of Nitrosomonas is greater than 40%, which means that nitrifying functional microorganisms dominate the system. Nitrosomonas with higher abundance can significantly increase the conversion rate of ammonia nitrogen to nitrite, thereby enhancing the efficiency of short-range nitrification, and can effectively compete and inhibit the second step of the nitrification process, thereby achieving the accumulation of nitrite, which is beneficial to short-range nitrification and subsequent denitrification. Finally, nitrosating bacteria can maintain a high ammonia nitrogen removal capacity under load fluctuations, oxygen concentration changes, etc., and enhance the operating stability of the system; Extracellular Polymeric Substances (EPS, Extracellular Polymeric Substances) EPS is a substance secreted by microorganisms during metabolism, such as polysaccharides and proteins. These substances play a role in protecting and supporting microbial communities in sludge. EPS can increase the cohesion of sludge particles, improve the sedimentation performance of sludge, and ensure good solid-liquid separation in the reactor. EPS also provides a protective barrier for microorganisms, which can improve their tolerance to changes in the external environment and enhance the system's ability to resist shocks. Finally, EPS helps stabilize the structure of microbial communities and promote the long-term survival and activity of Nitrosomonas and other bacteria in the reactor. Denitrifying bacteria can reduce nitrite or nitrate to nitrogen gas and are an important microbial community in the short-range nitrification-denitrification system. Denitrifying bacteria can Under the following conditions, nitrite can be directly converted into nitrogen gas, thereby reducing nitrogen pollution and improving the total nitrogen removal rate. In the short-term nitrification process, the accumulation of nitrite may lead to secondary pollution, while denitrifying bacteria can consume these intermediate products in time to reduce the accumulation of nitrate and nitrite. Anaerobic bacteria are mainly responsible for the degradation of organic matter or the auxiliary role of ammonia nitrogen conversion process in the reactor. Anaerobic bacteria can degrade organic matter in wastewater and reduce the interference of carbon-nitrogen imbalance on short-term nitrification. Anaerobic bacteria and other bacterial species form a diverse microbial ecosystem, which helps to maintain the microecological balance in the reactor and improve the system's ability to resist fluctuations. Anaerobic bacteria can synergize with denitrifying bacteria to improve the reduction and utilization of nitrite and further reduce nitrogen pollution.

[0018] In one technical solution of the present invention, in step S200: the concentration range of ammonium salt is between 0-200 mgN / L; and / or the concentration range of bicarbonate is between 0-200 mgN / L; and / or the concentration range of phosphate is between 0-1.74 mgP / L.

[0019] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: ammonium salt is the main nitrogen source in the treatment of ammonia nitrogen wastewater, and participates in the nitrification and short-range nitrification process of ammonia nitrogen. The ammonium salt concentration is in the range of 0-200 mgN / L, which means that the concentration of ammonia nitrogen in the wastewater can be adjusted to optimize the ammonia nitrogen conversion efficiency in the nitrification process, and helps to maintain the appropriate concentration of ammonia nitrogen in the reactor, avoiding the inhibitory effect of excessive ammonia nitrogen concentration on the nitrification process and microorganisms. In the concentration range of 0-200 mgN / L, the ammonium salt concentration is moderate, which is conducive to the growth and metabolism of nitrifying bacteria, thereby improving the conversion rate of ammonia nitrogen and the short-range nitrification effect, and helping to improve the stability of the system, avoiding ammonia nitrogen poisoning caused by excessively high concentrations or stagnation of the nitrification process caused by too low concentrations; bicarbonate, as a buffer substance in water, helps to maintain the p in the reactor. The stability of the H value can avoid the pH value being too low due to the acidic by-products in the nitrification process, which will affect the activity of microorganisms. The appropriate concentration of bicarbonate can effectively buffer the acid produced in the reaction and keep the pH value within an appropriate range, which is beneficial to the activity of nitrifying microorganisms and the conversion of ammonia nitrogen. It can help maintain the pH stability in the reactor and avoid the reduction of nitrite or ammonia nitrogen removal efficiency in an acidic environment. Phosphate is an essential nutrient element required for microbial growth, especially in the autotrophic nitrification process, phosphorus is one of the key substances for cell synthesis and energy conversion. The appropriate concentration of phosphate can promote the growth and activity of Nitrosomonas and other nitrifying microorganisms, help maintain the reproduction and metabolic activities of microorganisms, and improve the conversion efficiency of ammonia nitrogen. Too low phosphate concentration will limit the growth of nitrifying bacteria and affect the removal effect of ammonia nitrogen.

[0020] In a technical solution of the present invention, in step S200: the carbon-nitrogen ratio in the water containing ammonium salt, bicarbonate and phosphate is 0.8, and the phosphorus-nitrogen ratio is 0.005; wherein the carbon source is carbonate or bicarbonate.

[0021] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the carbon-nitrogen ratio is one of the important parameters affecting microbial metabolism in the water treatment process, especially playing an important role in the biological transformation of ammonia nitrogen. Setting the carbon-nitrogen ratio to 0.8 helps to inhibit the occurrence of denitrification reaction and ensure that ammonia nitrogen is mainly removed through the nitrification process. In addition, since denitrification requires a carbon source as an electron donor, the carbon-nitrogen ratio within this range avoids the promotion of the denitrification process by excessive carbon sources, ensuring that the system mainly performs short-range nitrification, and microorganisms can perform nitrification reactions at an optimal rate, thereby improving the efficiency of converting ammonia nitrogen into nitrite, thereby improving the treatment effect of the system; the phosphorus-nitrogen ratio is the ratio of phosphorus source to nitrogen source in the reaction system , the phosphorus-nitrogen ratio is 0.005, indicating that the phosphorus concentration in the water is much lower than the nitrogen concentration, which means that the phosphorus source plays an auxiliary role in the system, mainly supporting the growth of microorganisms and avoiding the impact of insufficient phosphorus source on the nitrification process. Too high a phosphorus-nitrogen ratio leads to the accumulation of excessive phosphorus, which in turn leads to eutrophication of the water body; carbonates and bicarbonates, as carbon sources, can provide a buffering effect and provide the required carbon source for microorganisms. While maintaining the stability of the pH value in the reactor, they can also support the energy metabolism of microorganisms in the short-term nitrification process. As buffers and carbon sources, carbonates and bicarbonates can enhance the stability of the system and reduce the fluctuations in microbial activity caused by pH fluctuations, thereby ensuring the long-term and efficient operation of the short-term nitrification process.

[0022] In a technical solution of the present invention, in step S300: the aeration reaction is aerated for 30 minutes every 30 minutes; and / or the dissolved oxygen concentration during the aeration reaction is 0.1 mg / L; and / or the dissolved oxygen concentration is lower than 0.1 mg / L at the end of the aeration reaction.

[0023] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: in step S300, the intermittent aeration mode helps to simulate the natural oxygen supply situation, avoid excessive accumulation and depletion of dissolved oxygen in the reactor, make the supply and consumption of oxygen more balanced, thereby promoting aerobic reactions in the short-range nitrification process, while avoiding unnecessary energy consumption caused by excessive oxygen supply, and ensuring that the dissolved oxygen is at a lower level to meet the needs of autotrophic short-range nitrification microorganisms, avoid excessive growth or competition of microorganisms due to continuous aeration, thereby maintaining the ecological balance in the reactor; at low dissolved oxygen concentrations, the system is conducive to The growth and activity of nitrite-transforming bacteria, which can convert ammonia nitrogen into nitrite, thereby removing ammonia nitrogen, can also reduce denitrification, avoid nitrogen oxides being converted into nitrogen gas to waste nitrogen sources, reduce oxygen consumption, and thus reduce the energy consumption of oxygen supply, thereby improving the energy efficiency of the system; at the end of the explosion, the oxygen concentration drops to an extremely low level, which is conducive to strengthening the dominant position of Nitrosomonas in the process of oxygen consumption, while reducing excessive promotion of other microorganisms, enhancing the short-term nitrification reaction in the autotrophic short-term nitrification process, and contributing to the formation of nitrite instead of further conversion into nitrate.

[0024] In a technical solution of the present invention, in step S300, the pH value of the second mixed solution is in the range of 8.8-9.

[0025] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the pH value of the second mixed solution is controlled within the range of 8.8-9, the nitrite-transforming bacteria are more active in a slightly alkaline environment, can effectively oxidize ammonia nitrogen into nitrite, and can maintain the optimal conditions for the reaction of ammonia nitrogen with oxygen, accelerate the conversion process of ammonia nitrogen, and improve the treatment efficiency of wastewater; on the one hand, the pH value plays a vital regulatory role in the growth and metabolism of microorganisms. Within this range, autotrophic short-range nitrifying bacteria can better adapt and grow, and improve their performance in the ammonia nitrogen conversion process. When the pH value is too low, some microorganisms may be inhibited or die; on the other hand, maintaining the pH within the range of 8.8-9 can effectively inhibit the activity of denitrifying bacteria, avoid nitrates from being reduced to nitrogen gas, and thus increase the conversion ratio of ammonia nitrogen to nitrite; finally, too low or too high a pH value may cause fluctuations in the activity of microorganisms in the reactor, thereby affecting the treatment effect. In this pH range, the smooth operation of microbial metabolism can be ensured, and the stability of the entire system can be improved.

[0026] The present invention provides an application of ammonia nitrogen wastewater short-range nitrification, which adopts any of the above methods, and thus includes the beneficial effects of any of the above technical solutions, which will not be elaborated here.

[0027] After adopting the technical solution of the present invention, the following technical effects can be achieved:

[0028] (1) Low greenhouse gas production: After low-concentration cerium treatment, nitrogen loss and greenhouse gases were reduced by 83%;

[0029] (2) Strong treatment capacity: The nitrite accumulation rate and treatment capacity increased by 33% during the long-term operation stage;

[0030] (3) Easy control: Key operating parameters such as pH value, dissolved oxygen concentration and cerium ion required for long-term operation have fixed parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the description of the embodiments 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 creative work.

[0032] Figure 1 This is a graph showing the change in nitrogen concentration during long-term operation before and after low-dose cerium treatment in Example 1 of the present invention;

[0033] Figure 2 This is a graph showing the change in total nitrogen in long-term operation before and after low-dose cerium treatment in Example 1 of the present invention;

[0034] Figure 3 is a graph of nitrogen conversion rates before and after low-dose cerium treatment provided by the batch test in Example 1 of the present invention;

[0035] Figure 4 is a diagram of the microbial community structure before and after low-dose cerium treatment in Example 1 of the present invention;

[0036] Figure 5 This is an expression evolution diagram of the nitrogen conversion enzyme related pathway in Example 1 of the present invention. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention are described clearly and completely. 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.

[0038] The invention provides a method for short-range nitrification of ammonia nitrogen wastewater. The method comprises the following steps: inoculated mature sludge is continuously operated for 20 days to simulate a short-range nitrification reactor that generates nitrogen loss after long-term operation; a large number of anaerobic fermentation bacteria and denitrification bacteria that are not adapted to cerium rapidly die by long-term treatment with low-dose cerium; heterotrophic nitrification-denitrification and anaerobic fermentation bacteria rapidly enrich cerium under the conditions of a concentration of 0-1.0 mg / L, a pH value of 8.9±0.3 and a dissolved oxygen of 0.1 mg / L, and become the main dominant bacteria next to nitrosomonas; anaerobic fermentation bacteria utilize EPS to decompose and produce suitable small molecular organic matter, heterotrophic nitrification-denitrification utilizes these endogenous organic carbon sources to convert ammonia nitrogen into nitrate, and reduces nitrate into nitrite, thereby realizing rapid realization of an autotrophic-endogenous heterotrophic short-range nitrification process; Nor enzyme is a key enzyme for converting nitrite into N2O, and low-dose cerium leads to significant downregulation of Nor enzyme expression, thereby reducing the generation of N2O and the realization of endogenous short-range denitrification.

[0039] Embodiment 1

[0040] This embodiment provides a method and application of short-range nitrification of ammonia nitrogen wastewater, and the specific operation steps are as follows:

[0041] S100, inoculation: inoculate mature autotrophic short-range nitrification sludge into a sequencing batch reactor with an effective volume of 4L and an effluent exchange ratio of 50% to obtain a first mixed solution.

[0042] Among them, the mature autotrophic short-term nitrification sludge is formed by cultivating ZL202210842055.1, and the short-term nitrification reactor in which the mature autotrophic short-term nitrification sludge has been running for 6 months, the volume of the autotrophic short-term nitrification sludge accounts for 3% of the effective volume of the reactor, the concentration of volatile suspended solids in the first mixed liquor is 1500mgVSS / L, the abundance of Nitrosomonas in the mature autotrophic short-term nitrification sludge is greater than 40%, and the mature autotrophic short-term nitrification sludge includes extracellular polymers, denitrifying bacteria, and anaerobic bacteria;

[0043] S200, water inlet: water containing 150 mg N / L, 150 mg C / L and 0.87 mg P / L of ammonium salt, bicarbonate and phosphate is delivered to the reactor through a water inlet pump, wherein the carbon-nitrogen ratio of the inlet water is 0.8, the phosphorus-nitrogen ratio is 0.005, and carbonate is used as the carbon source;

[0044] S300, stirring and aeration: mixing the first mixed solution in the reactor with water containing ammonium salt, bicarbonate and phosphate by a stirrer, and aerating for 30 minutes every 30 minutes for explosive reaction, the dissolved oxygen concentration during aeration is 0.1 mg / L, and a second mixed solution is obtained, and the pH value is maintained at 8.8;

[0045] S400, standing and separation: at a temperature range of 12-20°C, the stirring, aeration and pH control of the second mixed liquid are stopped, and solid-liquid separation is performed within 10 minutes to obtain treated water and sludge. At the end of the aeration reaction, the dissolved oxygen concentration is less than 0.1 mg / L;

[0046] S500, water discharge: start the water discharge pump to discharge the treated water evenly;

[0047] S600, operation: repeat steps S200-S500 to perform long-term operation for 20 days, add 0.5 mg / L cerium chloride solution, and continue to operate for 20 days.

[0048] Embodiment 2

[0049] This embodiment provides a method and application of short-range nitrification of ammonia nitrogen wastewater, and the specific operation steps are as follows:

[0050] S100, inoculation: inoculate mature autotrophic short-range nitrification sludge into a sequencing batch reactor with an effective volume of 4L and an effluent exchange ratio of 50% to obtain a first mixed solution.

[0051] Among them, the mature autotrophic short-term nitrification sludge is formed by cultivating ZL202210842055.1, and the short-term nitrification reactor in which the mature autotrophic short-term nitrification sludge has been running for 6 months, the volume of the autotrophic short-term nitrification sludge accounts for 5% of the effective volume of the reactor, the concentration of volatile suspended solids in the first mixed liquor is 2200mgVSS / L, the abundance of Nitrosomonas in the mature autotrophic short-term nitrification sludge is greater than 40%, and the mature autotrophic short-term nitrification sludge includes extracellular polymers, denitrifying bacteria, and anaerobic bacteria;

[0052] S200, water inlet: water containing 200 mgN / L, 200 mgC / L and 1.74 mgP / L of ammonium salt, bicarbonate and phosphate is delivered to the reactor through a water inlet pump, wherein the carbon-nitrogen ratio of the inlet water is 0.8, the phosphorus-nitrogen ratio is 0.005, and carbonate is used as the carbon source;

[0053] S300, stirring and aerating: mixing the first mixed solution in the reactor with water containing ammonium salt, bicarbonate and phosphate by a stirrer, and aerating for 30 minutes every 30 minutes for explosive reaction, the dissolved oxygen concentration during aeration is 0.1 mg / L, and a second mixed solution is obtained, and the pH value is maintained at 9;

[0054] S400, standing and separation: at a temperature range of 12-20°C, the stirring, aeration and pH control of the second mixed liquid are stopped, and solid-liquid separation is performed within 10 minutes to obtain treated water and sludge. At the end of the aeration reaction, the dissolved oxygen concentration is less than 0.1 mg / L;

[0055] S500, water discharge: start the water discharge pump to discharge the treated water evenly;

[0056] S600, operation: repeat steps S200-S500 to perform long-term operation for 20 days, add 2.5 mg / L cerium chloride solution, and continue to operate for 20 days.

[0057] Embodiment 2

[0058] This embodiment provides a method and application of short-range nitrification of ammonia nitrogen wastewater, and the specific operation steps are as follows:

[0059] S100, inoculation: inoculate mature autotrophic short-range nitrification sludge into a sequencing batch reactor with an effective volume of 4L and an effluent exchange ratio of 50% to obtain a first mixed solution.

[0060] Among them, the mature autotrophic short-term nitrification sludge is formed by cultivating ZL202210842055.1, and the short-term nitrification reactor in which the mature autotrophic short-term nitrification sludge has been running for 6 months, the volume of the autotrophic short-term nitrification sludge accounts for 4% of the effective volume of the reactor, the concentration of volatile suspended solids in the first mixed liquor is 2000mgVSS / L, the abundance of Nitrosomonas in the mature autotrophic short-term nitrification sludge is greater than 40%, and the mature autotrophic short-term nitrification sludge includes extracellular polymers, denitrifying bacteria, and anaerobic bacteria;

[0061] S200, water inlet: water containing 15 mgN / L, 15 mgC / L and 0.05 mgP / L of ammonium salt, bicarbonate and phosphate is delivered to the reactor through a water inlet pump, wherein the carbon-nitrogen ratio of the inlet water is 0.8, the phosphorus-nitrogen ratio is 0.005, and carbonate is used as the carbon source;

[0062] S300, stirring and aerating: mixing the first mixed solution in the reactor with water containing ammonium salt, bicarbonate and phosphate by a stirrer, and aerating for 30 minutes every 30 minutes for explosive reaction, the dissolved oxygen concentration during aeration is 0.1 mg / L, and a second mixed solution is obtained, and the pH value is maintained at 9;

[0063] S400, standing and separation: at a temperature range of 12-20°C, the stirring, aeration and pH control of the second mixed liquid are stopped, and solid-liquid separation is performed within 10 minutes to obtain treated water and sludge. At the end of the aeration reaction, the dissolved oxygen concentration is less than 0.1 mg / L;

[0064] S500, water discharge: start the water discharge pump to discharge the treated water evenly;

[0065] S600, operation: repeat steps S200-S500 to perform long-term operation for 20 days, add 0.05 mg / L cerium chloride solution, and continue to operate for 20 days.

[0066] Analysis of measurement indicators:

[0067] The inlet and outlet water samples were filtered through qualitative analysis filter paper for determination. 4+ -N, NO 2- -N and NO 3- -N concentration tests were conducted in accordance with the standard method of "Water and Wastewater Testing and Analysis Methods" (4th edition) compiled by the China Environmental Protection Administration;

[0068] NH 4+ -N quantitative detection was performed by Nessler's reagent spectrophotometry;

[0069] NO 2- -N quantitative detection was performed by N-(1-naphthyl)-ethylenediamine photometric method;

[0070] NO 3- -N quantitative detection was carried out by aminosulfonic acid UV spectrophotometry.

[0071] Sludge samples of Example 1 were obtained from the reactor on the 20th and 42nd days, respectively, and high-throughput sequencing, microbial community analysis and metabolic pathway analysis were performed.

[0072] like Figure 1 As shown, after the long-term operation from the 1st to the 20th day, the effluent nitrite nitrogen concentration began to be significantly lower than the inlet ammonia nitrogen concentration, while the effluent ammonia nitrogen and nitrate nitrogen concentrations were always at a low level, indicating that significant nitrogen loss occurred after the long-term operation of short-term nitrification; from the 21st to the 42nd day, after 0.5 mg / L of cerium was added to the inlet water, the effluent nitrite nitrogen concentration gradually approached the inlet ammonia nitrogen concentration, while the effluent ammonia nitrogen and nitrate nitrogen concentrations were always at a low level, indicating that the nitrogen loss of short-term nitrification was significantly reduced in the long-term operation, and the proportion of ammonia nitrogen converted to nitrite nitrogen increased significantly from 83.01±1.08% to 94.22±1.14%.

[0073] like Figure 2 As shown, after long-term operation from day 1 to day 20, the total nitrogen in the effluent was lower than that in the inlet, confirming the occurrence of a large amount of nitrogen loss; from day 21 to day 42, after 0.5 mg / L of cerium was added to the inlet, the nitrogen loss gradually decreased from 23.74±4.61 mg / L to 4.01±2.42 mg / L, a reduction of 83.11%.

[0074] like Figure 3 As shown, the nitrite production rate on the 20th day (R1) and the 42nd day (R2) was measured by sampling every hour. Compared with the nitrite production rate of R1 (6.66±0.87mgN / L / h), the nitrite production rate of R2 (8.89±2.85mgN / L / h) increased by 33.48%.

[0075] like Figure 4As shown in the data, norank_A4b is an anaerobic fermentation bacterium that can decompose the macromolecular EPS in the sludge into easily utilized small molecular organic matter; Pseudofulvimonas is classified as heterotrophic nitrification-aerobic denitrification, and is reported to utilize small molecular organic matter for endogenous heterotrophic short-term nitrification to produce nitrite; as a functional bacterium for short-term nitrification, the relative abundance of Nitrosomonas decreased from 43.53% to 16.85%, while the amount and rate of nitrite production increased significantly, indicating that endogenous short-term denitrification became an important pathway for nitrite supply after 0.5 mg / L cerium treatment.

[0076] like Figure 5 As shown, the expression of functional enzymes in the autotrophic short-term nitrification process (Amo and Hao) was significantly downregulated by 51.09% and 50.36%, the expression of functional enzymes in the endogenous heterotrophic short-term nitrification process (Nad2) was significantly upregulated by 77.17%, and the expression of functional enzymes producing N2O (NirBC and Nor) was significantly downregulated by 32.21% and 38.98%.

[0077] 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for short-cut nitrification of ammonia nitrogen wastewater, characterized in that: The method comprises: S100, inoculation: inoculating mature autotrophic short-range nitrification sludge into the reactor to obtain a first mixed solution; S200, water inlet: transporting water containing ammonia salt, bicarbonate and phosphate into the reactor through a water inlet pump; S300, stirring and aerating: mixing the first mixed liquid in the reactor with the water containing ammonia salt, bicarbonate and phosphate by a stirrer, and performing an explosive reaction to obtain a second mixed liquid; S400, standing and separating: stopping stirring, aeration and pH control of the second mixed liquid, performing solid-liquid separation, and obtaining treated water and sludge; S500, water discharge: activating the water discharge pump to evenly discharge the treated water; S600, operation: repeat steps S200-S500 for long-term operation; Wherein, step S600 also includes: adding cerium chloride solution and continuing the operation.

2. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: The step S600 specifically includes: S601, repeat steps S200-S500, and run for 20 days; S602. On the basis of step S601, add the cerium chloride solution and run for 20 days.

3. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: The concentration of the cerium chloride solution is 0.05-2.5 mg / L.

4. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In step S100: The reactor is a sequencing batch reactor; and / or The effective volume of the reactor is 4L; and / or The reactor outlet water exchange ratio is 50%; and / or The volume of the autotrophic short-range nitrification sludge accounts for 3%-5% of the effective volume of the reactor; and / or The volatile suspended solids concentration in the first mixed liquid is 1500-2200 mgVSS / L.

5. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In step S100: The abundance of Nitrosomonas in the mature autotrophic short-range nitrification sludge is greater than 40%; and / or The mature autotrophic short-term nitrification sludge includes at least one of extracellular polymers, denitrifying bacteria, and anaerobic bacteria.

6. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In step S200: The concentration of the ammonium salt is in the range of 0-200 mgN / L; and / or The concentration of bicarbonate is in the range of 0-200 mgN / L; and / or The concentration range of the phosphate is between 0-1.74 mgP / L.

7. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In the step S200: the carbon-nitrogen ratio in the water containing ammonium salt, bicarbonate and phosphate is 0.8, and the phosphorus-nitrogen ratio is 0.005; Wherein, the carbon source is carbonate or bicarbonate.

8. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In step S300: The explosion reaction is aeration for 30 minutes every 30 minutes; and / or The dissolved oxygen concentration during the explosion reaction is 0.1 mg / L; and / or When the explosion reaction ends, the dissolved oxygen concentration is lower than 0.1 mg / L.

9. The method for short-cut nitrification of ammonia nitrogen wastewater according to claim 1, characterized in that: In the step S300, the pH value of the second mixed solution is in the range of 8.8-9.

10. An application of short-cut nitrification of ammonia nitrogen wastewater, characterized in that: Ammonia nitrogen wastewater is treated by the method as described in any one of claims 1 to 9.

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