Active biological manganese oxide pool ABMP as well as construction method and application thereof

Abstract

The invention discloses an active biological manganese oxide pool ABMP as well as a construction method and application thereof. The construction method comprises the following steps that S1, anaerobic denitrification granular sludge is cultured for 20-40 days, the ratio of the first ammonia nitrogen concentration to the first nitrite nitrogen concentration of inlet water is 1: 1-1: 3, and the culture water temperature is 28-32 DEG C; s2, 15-25 mg / L of Mn < 2 + > is added along with inflow water, and culture continues to be conducted for 20-40 days; s3, the first ammonia nitrogen concentration and the first nitrite nitrogen concentration of the inlet water are increased to a second ammonia nitrogen concentration and a second nitrite nitrogen concentration, the concentration of Mn < 2 + > is increased to 35-45 mg / L, the culture water temperature is increased to 38-42 DEG C, C / N of the inlet water is kept to be 2-3, culture continues to be conducted for 20-40 days, and the ratio of the second ammonia nitrogen concentration to the second nitrite nitrogen concentration is 1: 1-1: 3. According to the application, the accumulation of the biological manganese oxide BioMnOx and the construction of ABMP are promoted by regulating the ammonia nitrogen concentration, the nitrite nitrogen concentration and the Mn < 2 + > concentration in the inlet water in stages and introducing AHLs. According to the anaerobic denitrification granular sludge reactor, manganese circulation and nitrogen conversion in the reactor can be maintained for a long time, and meanwhile efficient denitrification can be achieved under the condition of the extremely low carbon-nitrogen ratio.

Description

Technical Field

[0001] The present invention relates to the technical field of microbial wastewater denitrification, and more specifically, to an Active BioMnO x -Pool (ABMP), a method for constructing the same, an application thereof, an anaerobic denitrifying granular sludge reactor, and a method for treating wastewater with a low carbon-nitrogen ratio. Background Art

[0002] Eutrophication of water bodies is one of the most disturbing water quality problems faced by humans in recent decades. Eutrophication seriously damages the supply, regulation, maintenance functions, and cultural functions of water body ecosystem services, which not only destroys the ecological environment but also affects the safety of human water use. In the geochemical cycle, the nitrogen cycle mainly proceeds through ammonification, nitrification, and denitrification processes; domestic sewage and industrial wastewater contain various pollutants, including nitrogen-containing compounds, which need to be removed before discharge.

[0003] Anaerobic ammonium oxidation (Anammox) is an efficient autotrophic microbial denitrification technology that oxidizes ammonium nitrogen (NH4 - -N) to nitrogen gas (N2) using nitrite (NO2 + -N) as an electron acceptor under anaerobic conditions. Compared with the traditional nitrification-denitrification process, Anammox does not require external organic carbon sources and aeration, so it has advantages such as low energy consumption and low sludge production. However, the Anammox process is highly sensitive to environmental conditions such as temperature, salinity, and organic pollutant content. The concentration of heavy metal ions in the environment has a significant impact on the growth of anaerobic ammonium oxidation bacteria and the operation effect of the Anammox process.

[0004] Manganese is the third most abundant transition metal element in the earth's crust and is a cofactor of many microbial enzymes, participating in the energy and redox metabolism processes of microorganisms. In water bodies, manganese mainly exists in the divalent (Mn(II)) and tetravalent (Mn(IV)) forms and converts between different valence states through redox reactions. Microorganisms participate in the manganese cycle through redox reactions, and the redox cycle of manganese in water bodies has an important impact on the microbial denitrification process. Studies have reported on manganese-driven autotrophic denitrification (NDMO), which simultaneously removes nitrate and organic pollutants using (Mn(II)) as an inorganic electron donor. In addition, the bio-manganese oxide (BioMnO x ) produced by this process can also serve as an electron acceptor, inducing a novel manganese ammonium oxidation (Mnammox) process, thereby forming a manganese-nitrogen cycle in the reactor. Also, because of its ability to simultaneously remove nitrogen and organic pollutants, it has become one of the frontiers of microbial denitrification research. At the same time, compared with MnO produced by traditional chemical methods xCompared with, biological manganese oxide BioMnO x has a larger specific surface area and higher catalytic activity. At the same time, it has strong redox ability and catalytic performance.

[0005] At present, the existing research on the interaction between manganese and the Anammox system is very one-sided. Most of the research is limited to the effect of manganese on the nitrogen removal effect of the anaerobic ammonia oxidation reactor, ignoring the morphology, valence transformation of manganese in the Anammox reactor, and the accumulation of biological manganese oxide BioMnO x in the reactor and its application value. The accumulation of biological manganese oxide BioMnO x in the microbial nitrogen removal reactor is usually very slow, which leads to its role in the microbial nitrogen removal reactor being often ignored, and the construction method of ABMP has not been deeply studied. Summary of the Invention

[0006] In view of the above disadvantages of the prior art, the purpose of this application is to cross-fuse the redox cycle of manganese and the microbial metabolism of nitrogen to provide a rapid construction method of ABMP and an efficient nitrogen removal method for low carbon-nitrogen ratio wastewater.

[0007] Biological manganese oxide BioMnO x The continuously accumulating ABMP, as an important reaction center of the manganese cycle in the Mnammox-NMDO system, has the characteristics of strong redox ability and large specific surface area. On the one hand, as an electron acceptor, it can oxidize ammonia nitrogen in nitrogen-containing wastewater (3MnO2 + NH4 + + 4H + → 3Mn 2+ + NO2 - + 4H2O), on the other hand, the reduced low-valent manganese can drive manganese autotrophic denitrification (5Mn 2+ + 2NO3 - + 4H2O → 5MnO2 + N2 + 8H + ; 3Mn 2+ + 2NO2 - + 2H2O → 3MnO2 + N2 + 4H + ), and thus is oxidized to a high valence, thereby realizing the manganese cycle in the system.

[0008] However, the accumulation of biological manganese oxide BioMnO x in the microbial nitrogen removal reactor is usually very long. In this application, through the staged regulation of the Mn 2+ concentration, ammonia nitrogen concentration, nitrite nitrogen concentration, and culture water temperature in the influent, and further introducing AHLs, especially the quorum sensing molecule C8-HSL, to improve the electron transfer ability of nitrogen-removing microorganisms and the synthesis of conductive flagella, thereby promoting the interaction between nitrogen-removing microorganisms and Mn to a certain extent.2+ electron transfer between them to improve the manganese oxidation efficiency and accelerate the accumulation of biological manganese oxide BioMnO x and the construction of ABMP. ABMP significantly affects the diversity of the nitrogen metabolism pathway of the system microbial community. During the anaerobic microbial denitrification process dominated by Anammox, the construction of ABMP will become the "bridge" for the coupling of the Anammox system and the Mnammox-NMDO system (0.24Mn 2+ +NH4 + +1.84NO2 - +0.24H + →0.36NO3 - +2.48N2↑+2.12H2O+0.24MnO2), realizing the manganese cycle and efficient nitrogen removal.

[0009] More specifically, in the first aspect, the present application provides a method for constructing ABMP, including the following steps:

[0010] S1. Cultivate anaerobic denitrifying granular sludge for 20 - 40 days, where the concentration ratio of the first ammonia nitrogen to the first nitrite nitrogen in the influent is 1:1 - 1:3, and the cultivation water temperature is 28 - 32 °C;

[0011] S2. Add 15 - 25 mg / L of Mn 2+ with the influent and continue to cultivate for 20 - 40 days;

[0012] S3. Increase the concentration of the first ammonia nitrogen and the first nitrite nitrogen in the influent to the second ammonia nitrogen concentration and the second nitrite nitrogen concentration, increase the Mn 2+ concentration to 35 - 45 mg / L, and maintain the influent C / N = 2 - 3, increase the cultivation water temperature to 38 - 42 °C, and continue to cultivate for 20 - 40 days, where the concentration ratio of the second ammonia nitrogen to the second nitrite nitrogen is 1:1 - 1:3.

[0013] Preferably, steps S1 - S3 further include maintaining the stirring speed at 30 - 60 rpm, and / or the first ammonia nitrogen concentration is 15 - 30 mg / L, and / or the second ammonia nitrogen concentration is 1.5 - 2.5 times that of the first ammonia nitrogen concentration.

[0014] Preferably, the relative abundance of anaerobic ammonium oxidation bacteria in the anaerobic denitrifying granular sludge accounts for 30 - 50% of the anaerobic denitrifying granular sludge.

[0015] Preferably, step S2 further includes: adding 0.05 - 0.075 mg / L of AHLs with the influent, and / or maintaining the influent C / N = 0.5 - 1.5.

[0016] Preferably, step S3 further includes: increasing the concentration of AHLs in the influent to 0.1 - 0.2 mg / L.

[0017] In a second aspect, the present application provides an active biological manganese oxide pool ABMP, which is prepared by the above-mentioned construction method of the active biological manganese oxide pool ABMP.

[0018] In a third aspect, the present application provides an anaerobic denitrification granular sludge reactor, which constructs an active biological manganese oxide pool ABMP through the above-mentioned construction method of the active biological manganese oxide pool ABMP, or contains the above-mentioned active biological manganese oxide pool ABMP.

[0019] In a fourth aspect, the present application provides the use of the above-mentioned active biological manganese oxide pool ABMP or the above-mentioned anaerobic denitrification granular sludge reactor in treating low carbon-nitrogen ratio wastewater.

[0020] Preferably, the C / N in the low carbon-nitrogen ratio wastewater is ≤3.

[0021] In a fifth aspect, the present application provides a method for treating low-carbon-nitrogen ratio wastewater, comprising passing the low-carbon-nitrogen ratio wastewater into an anaerobic denitrification granular sludge reactor, wherein the C / N in the low-carbon-nitrogen ratio wastewater is ≤3.

[0022] Preferably, the low carbon-nitrogen ratio wastewater is continuously fed with a hydraulic retention time of ≥12h.

[0023] The technical solution of this application achieves the following technical effects:

[0024] 1. During the cultivation of anaerobic denitrification granular sludge, the concentration of ammonia nitrogen, nitrite nitrogen and Mn 2+ The concentration is regulated in stages to promote the production of biomanganese oxides with various valence states, mainly tetravalent manganese. x Specifically, in the first stage, the anaerobic denitrification granular sludge was cultured stably for 20-40 days at a water temperature of 28-32°C, wherein the first ammonia nitrogen concentration of the influent: the first nitrite nitrogen concentration = 1:1-1:3; in the second stage, 15-25 mg / L of Mn was added to the influent. 2+ , continue to cultivate for 20-40 days; in the third stage, increase the first ammonia nitrogen concentration and the first nitrite nitrogen concentration of the influent to the second ammonia nitrogen concentration and the second nitrite nitrogen concentration, increase Mn 2+ The concentration is increased to 35-45 mg / L, the culture water temperature is increased to 38-42°C, and the influent C / N is maintained at 2-3, and the culture is continued for 20-40 days, wherein the second ammonia nitrogen concentration: the second nitrite nitrogen concentration = 1:1-1:3.

[0025] 2. In the process of constructing ABMP, the present application introduces AHLs, a quorum sensing molecule, to improve the electron transfer ability and the synthesis of conductive flagella of denitrifying microorganisms, thereby promoting the interaction between denitrifying microorganisms and Mn2+ to improve the electron transfer between them and enhance the manganese oxidation efficiency, accelerating the accumulation of bio-manganese oxide BioMnO x and the construction of ABMP.

[0026] 3. In the anaerobic denitrifying granular sludge reactor constructed in this application for treating nitrogen-containing wastewater, especially wastewater with a low carbon-nitrogen ratio, ABMP will become the reaction center of the Anammox-coupled Mnammox-NMDO system. During the process, NH4 + -N is oxidized to NO3-N (Anammox) and NO2 - -N (Mnammox), and the reduced low-valent manganese can, under the action of microorganisms, reduce NO3 - -N and NO2 - -N back to N2 (NMDO), achieving efficient nitrogen removal with a total nitrogen removal rate exceeding 90%.

[0027] 4. The anaerobic denitrifying granular sludge reactor constructed in this application can maintain the manganese cycle and nitrogen conversion in the reactor for a long time, and can achieve efficient denitrification under extremely low carbon-nitrogen ratio conditions (C / N ≤ 3, for example, C / N = 0.5 - 2), with a low amount of excess sludge and no generation of greenhouse gases such as N2O during the traditional nitrification and denitrification processes.

[0028] The following will further illustrate the concept, specific structure, and technical effects of this application in conjunction with the attached drawings to fully understand the purpose, features, and effects of this application. Description of the Drawings

[0029] Figure 1 is a comparison diagram of the morphology of granular sludge during the construction of ABMP in the second stage of Example 1 of this application. The left figure is before the construction of ABMP, and the right figure is after the construction of ABMP.

[0030] Figure 2 is an SEM image of ABMP attached to the surface of anaerobic denitrifying granular sludge in the third stage of Example 1 of this application.

[0031] Figure 3 is another SEM image of ABMP attached to the surface of anaerobic denitrifying granular sludge in the third stage of Example 1 of this application.

[0032] Figure 4 is a TEM image of ABMP attached to the surface of anaerobic denitrifying granular sludge in the third stage of Example 1 of this application. It can be seen that bio-manganese oxide BioMnO x is distributed in the EPS around the denitrifying microorganisms.

[0033] Figure 5It shows the change in the mass percentage of manganese element on the surface of granular sludge in the reactor before and after the construction of ABMP in Example 1 of this application. The data is obtained by EDS energy spectrum.

[0034] Figure 6 It is the XPS comparison spectrum of granular sludge in the reactor before and after the construction of ABMP in Example 1 of this application.

[0035] Figure 7 It is the XRD comparison spectrum of granular sludge in the reactor before and after the construction of ABMP in Example 1 of this application.

[0036] Figure 8 It is about NH4 + -N, TN, NO2 - -N, Mn 2+ Statistical chart of influent and effluent concentration changes.

[0037] Figure 9 It is about NH4 + -N, TN, NO2 - -N, Mn 2+ Statistical chart of influent and effluent concentration changes.

[0038] Figure 10 It is about NH4 + -N, TN, NO2 - -N, Mn 2+ Statistical chart of influent and effluent concentration changes.

[0039] Figure 11 It is about NH4 + -N, TN, NO3 - -N, Mn 2+ Statistical chart of influent and effluent concentration changes. Detailed implementation manners

[0040] The following specific examples illustrate the implementation manners of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, without conflict, the following examples and the features in the examples can be combined with each other.

[0041] For the purpose of illustration, some exemplary embodiments of this application are described. It should be understood that this application can be implemented in other ways not specifically shown in the drawings.

[0042] "Active BioMnO in the active biological manganese oxide pool" involved in this application x-Pool (x = 1 - 2)", abbreviated as ABMP, refers to Mn 2+ As an electron donor, it participates in the life activities of microorganisms with manganese oxidation ability. The polymer of manganese oxides with multiple valence states formed after oxidation has characteristics such as a larger specific surface area, stronger biological affinity, and stronger redox ability compared to manganese oxides obtained by chemical processes.

[0043] The method for constructing ABMP provided in this application, during the cultivation of anaerobic denitrifying granular sludge, through the staged regulation of the ammonia nitrogen concentration, nitrite nitrogen concentration, and Mn 2+ concentration in the influent water, to promote the accumulation of biological manganese oxide BioMnO x and the construction of ABMP. Specifically, it includes the following three stages: The first stage, under the condition of maintaining the cultivation water temperature at 28 - 32 °C, the anaerobic denitrifying granular sludge is stably cultivated for 20 - 40 days, where the first ammonia nitrogen concentration in the influent water: the first nitrite nitrogen concentration = 1:1 - 1:3; The second stage, 15 - 25 mg / L of Mn 2+ is added with the influent water and cultivation continues for 20 - 40 days; The third stage, the first ammonia nitrogen concentration and the first nitrite nitrogen concentration in the influent water are increased to the second ammonia nitrogen concentration and the second nitrite nitrogen concentration, the Mn 2+ concentration is increased to 35 - 45 mg / L, the cultivation water temperature is increased to 38 - 42 °C, and the influent C / N = 2 - 3 is maintained, and cultivation continues for 20 - 40 days, where the second ammonia nitrogen concentration: the second nitrite nitrogen concentration = 1:1 - 1:3. The following is a detailed introduction to each stage.

[0044] Regarding the first stage

[0045] For the cultivation of anaerobic denitrifying granular sludge, an anaerobic microbial denitrification reactor for accommodating anaerobic denitrifying granular sludge needs to be constructed. This reactor has good sealing performance, is equipped with a reaction zone, a sedimentation zone, has a stirring device and a microbial retention device, and also has supporting inlet and outlet facilities. The reactor is immersed in an opaque incubator, and a temperature control heating rod is installed inside the incubator to maintain the water temperature at 28 °C - 32 °C and the stirring speed at 30 - 60 rpm.

[0046] The anaerobic denitrifying granular sludge is inoculated into the above-mentioned anaerobic microbial denitrification reactor whose sealing performance has been tested, maintaining the MLVSS at 7000 - 8000 mg / L, and the relative abundance of anaerobic ammonium-oxidizing bacteria in the anaerobic denitrifying granular sludge accounts for 30 - 50%.

[0047] In some of these embodiments, a peristaltic pump is used as the water inlet device to supply water to the above anaerobic microbial denitrification reactor. During the continuous flow operation of the reactor, according to the effective volume of the reactor and the influent flow rate, the hydraulic retention time (HRT) is calculated and maintained at a set time (such as 24 h, 12 h, etc., specifically selected according to the actual situation). At this stage, the ratio of the first ammonia nitrogen concentration to the first nitrite nitrogen concentration in the influent is 1:1 - 1:3; for example, if the first ammonia nitrogen concentration in the influent is 20 mg / L, then the influent nitrite nitrogen concentration is 20 - 60 mg / L. It should be understood that for the specific concentration values of the first ammonia nitrogen concentration and the first nitrite nitrogen concentration, the present application does not make any limitations, as long as it can meet the growth of anaerobic ammonium oxidation bacteria. Regarding the specific preparation concentrations of ammonia nitrogen and nitrite nitrogen, since the inoculated sludge in the present application is anaerobic sludge dominated by Anammox, this type of microorganism denitrifies ammonia nitrogen and nitrite nitrogen simultaneously in a certain ratio (1:1.32), but there are also other denitrifying bacteria in the inoculated sludge, so the ammonia nitrogen concentration:nitrite nitrogen concentration is set to 1:1 - 1:3. In the stable stage after sludge inoculation, when the ammonia nitrogen concentration is too high, the concentration of free ammonia (NH3) increases, which is highly toxic to bacteria and inhibits their activity and proliferation; similarly, when the nitrite nitrogen concentration is too high, it is more toxic to bacteria. Therefore, it is preferably that the ammonia nitrogen concentration in the first stage is not higher than 40 mg / L (such as 15 - 30 mg / L), and the nitrite nitrogen concentration is not higher than 80 mg / L. It should be understood that if the bacteria can still survive normally and denitrify at a concentration higher than this, an ammonia nitrogen concentration higher than 40 mg / L and a nitrite nitrogen concentration higher than 80 mg / L are still applicable.

[0048] During the cultivation process of the first stage, the dissolved oxygen concentration is controlled below 0.5 mg / L by aerating nitrogen into the influent to provide a suitable living environment for anaerobic ammonium oxidation bacteria. The internal water temperature of the reactor is controlled at 28 - 32 °C to provide suitable growth conditions for the flora dominated by anaerobic ammonium oxidation.

[0049] The cultivation time of the first stage, that is, the stable operation time of the above anaerobic microbial denitrification reactor, can be selected according to the actual situation, as long as it can meet that the MLVSS of the anaerobic denitrifying granular sludge does not decrease significantly and the total nitrogen removal rate of the anaerobic denitrifying granular sludge for the influent reaches more than 70%, such as 20 days, 30 days, 25 days, 35 days, etc. The number of days in the following embodiments does not constitute a limitation of the present application. In some of these embodiments, the cultivation time of the first stage is 20 - 40 days.

[0050] Regarding the second stage

[0051] After the first stage is completed, the cultivation then enters the second stage. At this stage, the ammonia nitrogen concentration and the nitrite nitrogen concentration are the same as those in the first stage, and the temperature and stirring speed are also the same as those in the first stage. The difference is that 15 - 25 mg / L of Mn is added with the influent.2+ , as an option, it is added with the influent water in the form of anhydrous manganese chloride because chloride ions are relatively stable in the reactor. For other manganese salts such as manganese sulfate and manganese nitrate, other ions may be introduced. Regarding the Mn 2+ concentration, it is specifically set considering that this concentration will not cause biological toxicity and serious negative impacts on the microorganisms inoculated in this application, and can participate in the denitrification process of the microorganisms.

[0052] In some of these embodiments, after the influent solution is configured, it is aerated with nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.5 mg / L) in the solution.

[0053] The inventors of this application found that in the process of constructing ABMP, by introducing this quorum-sensing molecule AHLs, the electron transfer ability of denitrifying microorganisms and the synthesis of conductive flagella can be improved, thereby promoting to a certain extent the electron transfer between denitrifying microorganisms and Mn 2+ to improve the manganese oxidation efficiency and accelerate the accumulation of bio-manganese oxide BioMnO x and the construction of ABMP. Therefore, as an option, 0.05 - 0.075 mg / L AHLs is added with the influent water. For example, 0.05 mg / L AHLs is added in the form of C8-HSL. It should be understood that the addition of AHLs can accelerate the accumulation of bio-manganese oxide BioMnO x In the actual process, it can also be not added, but this does not affect the successful construction of ABMP.

[0054] At this stage, in order to drive the activity of Mnammox bacteria in the reactor, an organic carbon source can be introduced into the influent water, for example, maintaining C / N = 0.5 - 1.5. The carbon source can be in the form of sodium acetate. Of course, other forms of carbon sources can also be used, such as sodium citrate, etc. This application does not make any limitations. At this stage, the introduction of Mn 2+ stimulates to a certain extent the increase in the abundance of manganese autotrophic denitrifying bacteria, and at the same time the addition of AHLs will promote the production of microbial conductive flagella. Manganese autotrophic denitrifying bacteria use Mn 2+ as an inorganic electron donor to reduce nitrite nitrogen, and Mn 2+ is oxidized to a higher valence during this process, resulting in the accumulation of bio-manganese oxide BioMnO x starting to accumulate.

[0055] The cultivation time of the second stage can be selected according to the actual situation. It is found through SEM characterization that there are active bio-manganese oxides BioMnO with a particle size of 20 - 50 nm on the surface of anaerobic denitrifying granular sludge xAlternatively, if it is found by XPS characterization that the proportion of tetravalent manganese increases, it can indicate the completion of the second stage. Therefore, it may be, for example, 30 days, 25 days, 35 days, etc. The number of days in the following examples does not constitute a limitation of this application. In some of these embodiments, the cultivation time in the first stage is 20 - 40 days.

[0056] Regarding the third stage

[0057] After the completion of the second stage, the cultivation then enters the third stage. In this stage, the influent ammonia nitrogen concentration and nitrite nitrogen concentration are increased, the Mn 2+ concentration is increased to 35 - 45 mg / L, the cultivation water temperature is increased to 38 - 42 °C, and the influent C / N is maintained at 2 - 3, where the influent ammonia nitrogen concentration: influent nitrite nitrogen concentration = 1:1 - 1:3. The addition of more carbon sources in this stage causes the manganese ammonia-oxidizing bacteria to preferentially utilize the organic carbon source for manganese reduction. However, after the organic carbon source combines with the biological manganese oxide BioMnO x it will cover its surface, thereby reducing its active sites for accepting electrons and hindering the reduction of the biological manganese oxide BioMnO x and thus promoting the accumulation of the biological manganese oxide BioMnO x and further forming ABMP. In addition, since the NMDO bacteria have a wider temperature adaptation ability compared to the Mnammox bacteria, increasing the water temperature to 38 - 42 °C in this stage is more conducive to the NMDO process and facilitates the further accumulation of BioMnO x

[0058] In the third stage, the anaerobic denitrifying granular sludge in the reactor begins to change color. The construction of the active biological manganese oxide pool BioMnO x -Pool causes the color of the granular sludge to change from light red to dark brown, which is due to the attachment of a large amount of biological manganese oxide BioMnO x on the surface of the granular sludge. As the construction of the active biological manganese oxide pool BioMnO x -Pool is completed, the biological manganese oxide BioMnO x with a particle size of 50 - 100 nm is evenly distributed on the surface of the granular sludge and is wrapped by EPS. And this part of the wrapped ABMP is more likely to accept electrons from the organic carbon source and ammonia nitrogen and becomes the reaction center of the Anammox-coupled Mnammox-NMDO system. After the successful construction of ABMP, the proportion of tetravalent manganese on the surface of the granular sludge is greatly increased, indicating that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of the anaerobic denitrifying granular sludge.

[0059] In some of these embodiments, the ammonia nitrogen concentration in the third stage is 1.5 - 2.5 times that in the first stage, and more preferably, the ammonia nitrogen concentration in the third stage is 2 times that in the first stage.

[0060] In some of these embodiments, as the Mn concentration in the third stage increases, the amount of electron donors increases accordingly. As an optional choice, the concentration of AHLs is increased, for example, increased to 0.1 - 0.2 mg / L, to improve the electron transfer efficiency. 2+ In some of these embodiments, the stirring speed can be the same as that in the previous stage or can be arbitrarily selected from 30 - 60 rpm.

[0061] This application also provides an ABMP, which is prepared by the method for constructing ABMP described above and will not be elaborated here.

[0062] This application further provides an anaerobic denitrifying granular sludge reactor, which constructs an ABMP by the method for constructing ABMP described above or contains the above ABMP. This anaerobic denitrifying granular sludge reactor can also be understood as the reactor obtained after completing the above first stage, second stage, and third stage. When treating nitrogen-containing wastewater, especially wastewater with a low carbon-nitrogen ratio (C / N ≤ 3, for example, C / N = 0.5 - 2), the ABMP will become the reaction center of the Anammox coupled with Mnammox-NMDO system. During the process, NH4-N is oxidized to NO3-N (Anammox) and NO2-N (Mnammox), and the reduced low-valent manganese can, under the action of microorganisms, reduce NO3-N and NO2-N to N2 (NMDO), achieving efficient nitrogen removal, and the total nitrogen removal rate exceeds 90%. In addition, this anaerobic denitrifying granular sludge reactor can maintain the manganese cycle and nitrogen conversion in the reactor for a long time, and the amount of excess sludge is low, without the generation of greenhouse gases such as N2O in the traditional nitrification and denitrification processes.

[0063] This application further provides a method for treating wastewater with a low carbon-nitrogen ratio, including introducing the wastewater with a low carbon-nitrogen ratio into the above anaerobic denitrifying granular sludge reactor. The C / N of the wastewater with a low carbon-nitrogen ratio is ≤ 3 (for example, C / N = 0.5 - 2), and the inorganic nitrogen in the wastewater with a low carbon-nitrogen ratio is a mixture of ammonia nitrogen and nitrite nitrogen, a mixture of ammonia nitrogen and nitrate nitrogen, or a mixture of ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen. + -N is oxidized to NO3 - -N (Anammox) and NO2 - -N (Mnammox), and the reduced low-valent manganese can, under the action of microorganisms, reduce NO3 - -N and NO2 - -N to N2 (NMDO), achieving efficient nitrogen removal, and the total nitrogen removal rate exceeds 90%. In addition, this anaerobic denitrifying granular sludge reactor can maintain the manganese cycle and nitrogen conversion in the reactor for a long time, and the amount of excess sludge is low, without the generation of greenhouse gases such as N2O in the traditional nitrification and denitrification processes.

[0064] This application further provides a method for treating wastewater with a low carbon-nitrogen ratio, including introducing the wastewater with a low carbon-nitrogen ratio into the above anaerobic denitrifying granular sludge reactor. The C / N of the wastewater with a low carbon-nitrogen ratio is ≤ 3 (for example, C / N = 0.5 - 2), and the inorganic nitrogen in the wastewater with a low carbon-nitrogen ratio is a mixture of ammonia nitrogen and nitrite nitrogen, a mixture of ammonia nitrogen and nitrate nitrogen, or a mixture of ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen.

[0065] In some of these embodiments, the wastewater with a low carbon-nitrogen ratio is fed continuously, and the hydraulic retention time is ≥ 12 h.

[0066] Construction of ABMP in Example 1 - Part 1

[0067] The first stage

[0068] The granular sludge seed liquid in this example was taken from an anaerobic ammonium oxidation UASB reactor that had been operating for more than one year. After 16srRNA sequencing, it was found that the dominant bacteria in the sludge were Brocadia bacteria, one of the typical anaerobic ammonium oxidation bacteria genera, with a relative abundance of 40%.

[0069] The granular sludge seed liquid was inoculated into an anaerobic microbial denitrification reactor with tested sealing performance, and the MLVSS was maintained at 7000 mg / L. The entire reactor was immersed in an opaque insulated box with a lid, which was equipped with two temperature - controllable heating rods and a stirring device, so that during the entire cultivation process, the water temperature inside the reactor remained at 28°C and the stirring speed was maintained at 60 rpm.

[0070] Prepare simulated wastewater according to the following formula and use a peristaltic pump to continuously feed water into the reactor with a hydraulic retention time of 24 h. Operate stably for 30 days to allow the inoculated sludge to adapt to the new environment in the reactor. At this time, the MLVSS of the denitrifying granular sludge does not decrease significantly and the total nitrogen removal rate of the denitrifying granular sludge for the influent water reaches over 70%. Among them: Composition of simulated wastewater: NH4 + -N 20 mg / L (prepared with NH4Cl), NO2 - -N 40 mg / L (prepared with NaNO2). At the same time, configure the trace elements required by microorganisms: NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, MgSO4 25 mg / L. All the reagents used in this example were purchased from Shanghai Titan Scientific Co., Ltd. and Shanghai Yuanye Bio - Technology Co., Ltd.

[0071] During the entire cultivation process, strictly control DO and conduct in - situ detection of the reactor effluent, with DO < 0.5 mg / L.

[0072] The second stage

[0073] During this stage, the nitrogen concentration, temperature, and stirring speed in the simulated wastewater remained unchanged. Add 20 mg / L Mn to the influent water in the form of MnCl2 2+ , and at the same time, add 0.05 mg / L AHLs to the influent water in the form of C8 - HSL. In order to drive the activity of Mnammox bacteria in the reactor, introduce an organic carbon source into the influent water in the form of sodium acetate and maintain C / N = 1. The introduction of Mn 2+ stimulated the increase in the abundance of manganese autotrophic denitrifying bacteria to a certain extent, and the addition of C8 - HSL will promote the production of microbial conductive flagella. Manganese autotrophic denitrifying bacteria utilize Mn 2+Using an inorganic electron donor to reduce nitrite nitrogen, Mn 2+ is oxidized to a higher valence during the process, resulting in the accumulation of the biological manganese oxide BioMnO x starting to accumulate. The operation time of the second stage is to continue operating for 30 days based on the first stage, that is, the reactor continues to operate from the 31st day to the 60th day in this stage.

[0074] The third stage

[0075] Increase the concentration of NH4 + -N in the influent to 40 mg / L, the concentration of NO2 - -N in the influent to 80 mg / L, increase the culture water temperature to 42 °C, at the same time increase C / N = 2, increase the concentration of Mn 2+ in the influent to 40 mg / L, C8-HSL to 0.2 mg / L, and keep the stirring speed the same as the previous stage. The addition of more carbon sources in this stage causes the manganeseammoxidizing bacteria to preferentially use organic carbon sources for manganese reduction, but the combination of organic carbon and the biological manganese oxide BioMnO x will cover its surface, thereby reducing its active sites for accepting electrons and hindering the reduction of the biological manganese oxide BioMnO x , thus promoting the accumulation of ABMP and completing the construction of ABMP. In addition, since NMDO bacteria have a wider temperature adaptation ability than Mnammox bacteria, increasing the water temperature to 42 °C in this stage is more beneficial to the NMDO process and facilitates the further accumulation of BioMnO x . The operation time of the second stage is to continue operating for 30 days based on the first stage, that is, the reactor continues to operate from the 61st day to the 90th day in this stage.

[0076] In this stage, the granular sludge in the reactor begins to change color. During the construction of ABMP, the color of the granular sludge changes from light red to dark brown (as Figure 1 shown), which is due to a large number of biological manganese oxides BioMnO with a particle size of 50 - 100 nm x being evenly distributed on the surface of the granular sludge and being wrapped by EPS (as Figure 2 and Figure 3 shown). Moreover, TEM images also confirm that EPS is filled with a large number of biological manganese oxides BioMnO x (as Figure 4 shown), and this part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen and becomes the reaction center of the Anammox coupled Mnammox-NMDO system. The EDS-mapping results (as Figure 5As shown, it also indicates that the mass percentage of manganese on the surface of granular sludge has increased significantly before and after the construction of ABMP. In addition, the XPS spectrum shows (as Figure 6 shown) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of granular sludge has increased greatly, which indicates that the free manganese ions entering the reactor are captured by EPS and then oxidized to high-valent manganese, thus being fixed on the surface of granular sludge. The conclusion of the XRD spectrum (as Figure 7 shown) also confirms the appearance of manganese oxide after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor by regulating the influent substances in the second and third stages.

[0077] Example 2 Construction of ABMP II

[0078] The first stage

[0079] The granular sludge seed liquid in this example was taken from an anaerobic ammonium oxidation UASB reactor that had been operating for more than one year. After 16srRNA sequencing, it was found that the dominant bacteria in the sludge were Brocadia bacteria, one of the typical anaerobic ammonium oxidation bacteria genera, with a relative abundance of 30%.

[0080] The granular sludge seed liquid was inoculated into an anaerobic microbial denitrification reactor with tested sealing performance, and the MLVSS was maintained at 8000 mg / L. The entire reactor was immersed in an opaque insulated box with a lid, which was equipped with two temperature-controlled heating rods and a stirring device, so that the water temperature inside the reactor remained at 32 °C and the stirring speed was maintained at 40 rpm during the entire cultivation process.

[0081] The simulated wastewater was prepared according to the following formula and continuously fed into the reactor with a peristaltic pump, and the hydraulic retention time was 24 h. It was stably operated for 25 days to allow the inoculated sludge to adapt to the new environment in the reactor. At this time, the MLVSS of the denitrifying granular sludge did not decrease significantly and the total nitrogen removal rate of the denitrifying granular sludge for the influent reached more than 70%. Among them: the composition of the simulated wastewater: NH4 + -N 15 mg / L (prepared with NH4Cl), NO2 - -N 45 mg / L (prepared with NaNO2). At the same time, the trace elements required by microorganisms were configured: NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, MgSO4 25 mg / L. All the reagents used in this example were purchased from Shanghai Titan Biotech Co., Ltd. and Shanghai Yuanye Biotech Co., Ltd.

[0082] During the entire cultivation process, the DO was strictly controlled, and the effluent of the reactor was in-situ detected, with DO < 0.5 mg / L.

[0083] The second stage

[0084] During this stage, the nitrogen concentration, temperature, and stirring speed in the simulated wastewater remained unchanged. 15 mg / L of Mn was added to the influent in the form of MnCl2. 2+ , and at the same time, 0.075 mg / L was added to the influent in the form of C8-HSL. To drive the activity of Mnammox bacteria in the reactor, an organic carbon source was introduced into the influent in the form of sodium acetate, and C / N was maintained at 0.5. The introduction of Mn 2+ stimulated the increase in the abundance of manganese autotrophic denitrifying bacteria to a certain extent. At the same time, the addition of C8-HSL promoted the production of microbial conductive flagella. Manganese autotrophic denitrifying bacteria used Mn 2+ as an inorganic electron donor to reduce nitrite nitrogen, and Mn 2+ was oxidized to a higher valence during the process, resulting in the accumulation of biological manganese oxide BioMnO x . The operation time of the second stage was 20 days based on the first stage, that is, the reactor continued to operate from day 26 to day 45 in this stage.

[0085] The third stage

[0086] increased the NH4 + -N concentration in the influent to 22.5 mg / L, the NO2 - -N concentration in the influent to 67.5 mg / L, increased the culture water temperature to 40 °C, and at the same time increased C / N = 2, increased the Mn 2+ concentration in the influent to 35 mg / L, and C8-HSL to 0.1 mg / L. The stirring speed was the same as the previous stage. The addition of more carbon sources in this stage caused the manganese ammonia-oxidizing bacteria to preferentially use organic carbon sources for manganese reduction. However, after the organic carbon combined with the biological manganese oxide BioMnO x , it would cover its surface, thereby reducing its active sites for accepting electrons and hindering the reduction of biological manganese oxide BioMnO x , thus promoting the accumulation of ABMP and completing the construction of ABMP. In addition, since NMDO bacteria have a wider temperature adaptation ability compared to Mnammox bacteria, increasing the water temperature to 40 °C in this stage is more conducive to the NMDO process and facilitates the further accumulation of BioMnO x . The operation time of the second stage was 27 days based on the first stage, that is, the reactor continued to operate from day 46 to day 72 in this stage.

[0087] In this stage, the granular sludge in the reactor began to change color. During the construction of ABMP, the color of the granular sludge changed from light red to dark brown (the attached drawings are omitted). This was due to a large number of biological manganese oxides BioMnO with a particle size of 50 - 100 nm xThey are evenly distributed on the surface of granular sludge and wrapped by EPS (accompanying drawings are omitted). Moreover, TEM images also confirm that a large amount of biological manganese oxide BioMnO fills EPS. x (Accompanying drawings are omitted). This part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen and becomes the reaction center of the Anammox-coupled Mnammox-NMDO system. The EDS-mapping results (accompanying drawings are omitted) also show that the mass percentage of manganese on the surface of granular sludge has increased significantly before and after the construction of ABMP. In addition, the XPS spectra show (accompanying drawings are omitted) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of granular sludge has increased greatly, indicating that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of granular sludge. The conclusion of the XRD spectra (accompanying drawings are omitted) also confirms the appearance of manganese oxides after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor by regulating the influent substances in the second and third stages.

[0088] Example 3 Construction of ABMP III

[0089] The first stage

[0090] The granular sludge seed liquid in this example was taken from an anaerobic ammonium oxidation UASB reactor that had been operating for more than one year. After 16srRNA sequencing, it was found that the dominant bacteria in the sludge were Brocadia bacteria, which are one of the typical anaerobic ammonium oxidation bacteria genera, with a relative abundance of 50%.

[0091] The granular sludge seed liquid was inoculated into an anaerobic microbial denitrification reactor whose sealing performance had been tested, and the MLVSS was maintained at 7500 mg / L. The entire reactor was immersed in an opaque insulated box with a lid, which was equipped with two temperature-controlled heating rods and a stirring device, so that during the entire cultivation process, the water temperature inside the reactor was maintained at 29 °C and the stirring speed was maintained at 30 rpm.

[0092] Prepare simulated wastewater according to the following formula and continuously feed the reactor with a peristaltic pump, with a hydraulic retention time of 24 h. Operate stably for 35 days to allow the inoculated sludge to adapt to the new environment in the reactor. At this time, the MLVSS of the denitrifying granular sludge does not decrease significantly and the total nitrogen removal rate of the denitrifying granular sludge for the influent reaches more than 70%. Among them: Composition of simulated wastewater: NH4 + -N 30 mg / L (prepared with NH4Cl), NO2 --N 30 mg / L (prepared with NaNO2). At the same time, prepare the trace elements required by microorganisms: NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, MgSO4 25 mg / L. All the reagents used in this example were purchased from Shanghai Titan Technology Co., Ltd. and Shanghai Yuanye Biotechnology Co., Ltd.

[0093] During the whole cultivation process, strictly control DO and conduct in-situ detection of the reactor effluent. DO < 0.5 mg / L.

[0094] The second stage

[0095] In this stage, the nitrogen concentration, temperature and stirring speed in the simulated wastewater remain unchanged. Add 25 mg / L Mn to the influent in the form of MnCl2 2+ , and at the same time, add 0.06 mg / L AHLs to the influent in the form of C8-HSL. In order to drive the activity of Mnammox bacteria in the reactor, introduce an organic carbon source into the influent in the form of sodium acetate and maintain C / N = 1.5. In this stage, the introduction of Mn 2+ stimulates the increase in the abundance of manganese autotrophic denitrifying bacteria to a certain extent. At the same time, the addition of C8-HSL will promote the production of microbial conductive flagella. Manganese autotrophic denitrifying bacteria use Mn 2+ as an inorganic electron donor to reduce nitrite nitrogen, and Mn 2+ is oxidized to a higher valence during the process, resulting in the accumulation of biological manganese oxide BioMnO x . The operation time of the second stage is to continue running for 35 days on the basis of the first stage, that is, the reactor continues to run from the 36th day to the 70th day in this stage.

[0096] The third stage

[0097] Increase the concentration of NH4 + -N in the influent to 45 mg / L, the concentration of NO2 - -N in the influent to 45 mg / L, raise the culture water temperature to 38 °C, at the same time increase C / N = 2.5, increase the concentration of Mn in the influent 2+ to 45 mg / L, C8-HSL to 0.15 mg / L, and keep the stirring speed the same as the previous stage. The addition of more carbon sources in this stage makes the manganese ammonia-oxidizing bacteria more inclined to use organic carbon sources for manganese reduction. However, after the organic carbon combines with the biological manganese oxide BioMnO x , it will cover its surface, thereby reducing the active sites for receiving electrons and hindering the biological manganese oxide BioMnO xReduction, thereby promoting the accumulation of ABMP and completing the construction of ABMP. In addition, since NMDO bacteria have a wider temperature adaptation ability compared to Mnammox bacteria, increasing the water temperature to 38 °C in this stage is more beneficial to the NMDO process, facilitating the further accumulation of BioMnO. x The operation time of the second stage is to continue running for 40 days based on the first stage, that is, the reactor continues to run from the 71st day to the 110th day in this stage.

[0098] In this stage, the granular sludge in the reactor begins to change in color. During the construction of ABMP, the color of the granular sludge changes from light red to dark brown (accompanying drawings omitted). This is because a large number of bio-manganese oxides BioMnO with a particle size of 50 - 100 nm are evenly distributed on the surface of the granular sludge and are wrapped by EPS (accompanying drawings omitted). Moreover, TEM images also confirm that a large number of bio-manganese oxides BioMnO are also filled in the EPS (accompanying drawings omitted). And this part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen, becoming the reaction center of the Anammox-coupled Mnammox-NMDO system. The EDS-mapping results (accompanying drawings omitted) also show that the mass percentage of manganese on the surface of the granular sludge has increased significantly before and after the construction of ABMP. In addition, XPS spectra show (accompanying drawings omitted) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of the granular sludge has greatly increased, indicating that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of the granular sludge. The conclusion of the XRD spectra (accompanying drawings omitted) also confirms the appearance of manganese oxides after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor through the regulation of influent substances in the second and third stages. x x x (accompanying drawings omitted), and this part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen, becoming the reaction center of the Anammox-coupled Mnammox-NMDO system. The EDS-mapping results (accompanying drawings omitted) also show that the mass percentage of manganese on the surface of the granular sludge has increased significantly before and after the construction of ABMP. In addition, XPS spectra show (accompanying drawings omitted) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of the granular sludge has greatly increased, indicating that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of the granular sludge. The conclusion of the XRD spectra (accompanying drawings omitted) also confirms the appearance of manganese oxides after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor through the regulation of influent substances in the second and third stages.

[0099] Example 4 Construction of ABMP Four

[0100] The First Stage

[0101] The granular sludge seed liquid in this example was taken from an anaerobic ammonium oxidation UASB reactor that had been operating for more than one year. After 16srRNA sequencing, it was found that the dominant bacteria in the sludge were Brocadia bacteria, one of the typical anaerobic ammonium oxidation bacteria genera, with a relative abundance of 45%.

[0102] The granular sludge seed liquid was inoculated into an anaerobic microbial denitrification reactor with tested sealing performance, maintaining the MLVSS at 7800 mg / L. The entire reactor was immersed in an opaque insulated box with a lid, which was equipped with two temperature-controlled heating rods and a stirring device, so that during the entire cultivation process, the water temperature inside the reactor remained at 30 °C and the stirring speed was maintained at 50 rpm.

[0103] Prepare the simulated wastewater according to the following formula and continuously feed the reactor with a peristaltic pump, with a hydraulic retention time of 24 hours. Stable operation for 30 days allows the inoculated sludge to adapt to the new environment in the reactor. At this time, the MLVSS of the denitrification granular sludge does not decrease significantly and the total nitrogen removal rate of the denitrification granular sludge in the influent reaches more than 70%. Among them: Simulated wastewater composition: NH4 + -N 20mg / L (prepared with NH4Cl), NO2 - -N 40mg / L (prepared with NaNO2). Meanwhile, the trace elements required by microorganisms were prepared: NaHCO3 100mg / L, KH2PO4 50mg / L, CaCl2 20mg / L, MgSO4 25mg / L. All the reagents used in this example were purchased from Shanghai Titan Biotechnology Co., Ltd. and Shanghai Yuanye Biotechnology Co., Ltd.

[0104] During the entire culture process, DO was strictly controlled and the reactor effluent was tested in situ, with DO < 0.5 mg / L.

[0105] Phase II

[0106] In this stage, the nitrogen concentration, temperature and stirring speed in the simulated wastewater remain unchanged, and 20 mg / L Mn is added to the influent in the form of MnCl2. 2+ In this stage, Mn 2+ The introduction of Mn has stimulated the abundance of manganese autotrophic denitrifying bacteria to a certain extent. 2+ As an inorganic electron donor to reduce nitrite, Mn 2+ In the process, it is oxidized to high valence, resulting in biomanganese oxide BioMnO x The second stage of operation is to continue the operation for 30 days based on the first stage, that is, the reactor will continue to operate from the 31st day to the 60th day.

[0107] Phase 3

[0108] Increase NH4 in the influent + -N concentration is 40mg / L, influent NO2 - -N concentration is 80mg / L, the culture water temperature is increased to 41℃, and C / N=2 is increased to increase the influent Mn 2+ The concentration was 40 mg / L, and the stirring speed was the same as in the previous stage. In this stage, the addition of more carbon sources caused the manganese ammonia oxidizing bacteria to prefer to use organic carbon sources for manganese reduction, but the organic carbon and biological manganese oxide BioMnO x After binding, the surface will be covered, thereby reducing its active sites for accepting electrons and hindering the biomanganese oxide BioMnOx reduction, thus promoting the accumulation of the active biological manganese oxide pool BioMnO x -Pool and completing the construction of ABMP. In addition, since NMDO bacteria have a wider temperature adaptation ability compared to Mnammox bacteria, increasing the water temperature to 41 °C at this stage is more conducive to the NMDO process and facilitates the further accumulation of BioMnO x The operation time of the second stage is to continue running for 30 days based on the first stage, that is, the reactor continues to run from the 61st day to the 90th day in this stage.

[0109] At this stage, the granular sludge in the reactor begins to change color. During the construction of the active biological manganese oxide pool BioMnO x -Pool, the color of the granular sludge changes from light red to dark brown (accompanying drawings are omitted). This is because a large number of biological manganese oxides BioMnO with a particle size of 50 - 100 nm are evenly distributed on the surface of the granular sludge and are wrapped by EPS (accompanying drawings are omitted). Moreover, TEM images also confirm that a large number of biological manganese oxides BioMnO are also filled in the EPS (accompanying drawings are omitted). x (accompanying drawings are omitted), and this part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen and becomes the reaction center of the Anammox-coupled Mnammox-NMDO system. The EDS-mapping results (accompanying drawings are omitted) also show that the mass percentage of manganese on the surface of the granular sludge has increased significantly before and after the construction of ABMP. In addition, XPS spectra show (accompanying drawings are omitted) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of the granular sludge has increased significantly. This indicates that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of the granular sludge. The conclusion of the XRD spectrum (accompanying drawings are omitted) also confirms the appearance of manganese oxides after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor through the regulation of influent substances in the second and third stages. x (accompanying drawings are omitted), and this part of the encapsulated ABMP is more likely to accept electrons from organic carbon sources and ammonia nitrogen and becomes the reaction center of the Anammox-coupled Mnammox-NMDO system. The EDS-mapping results (accompanying drawings are omitted) also show that the mass percentage of manganese on the surface of the granular sludge has increased significantly before and after the construction of ABMP. In addition, XPS spectra show (accompanying drawings are omitted) that after the successful construction of ABMP, the proportion of tetravalent manganese on the surface of the granular sludge has increased significantly. This indicates that the free manganese ions entering the reactor are captured by EPS and oxidized to high-valent manganese, thus being fixed on the surface of the granular sludge. The conclusion of the XRD spectrum (accompanying drawings are omitted) also confirms the appearance of manganese oxides after the construction of ABMP. These signs indicate that ABMP has been successfully constructed in the reactor through the regulation of influent substances in the second and third stages.

[0110] Example 5 Treatment of simulated wastewater with a low carbon-nitrogen ratio - I

[0111] Simulated wastewater was introduced into the anaerobic microbial denitrification reactor after the successful construction of ABMP in Example 1 as an example for denitrification treatment.

[0112] The reactor operates in a continuous mode, with a hydraulic retention time of 24 h and the water temperature maintained at 33 °C ± 1 °C. The simulated wastewater enters the reactor through the inlet pipe by a peristaltic pump and undergoes denitrification through the interaction of anaerobic denitrifying microorganisms and ABMP in the reactor.

[0113] Simulated wastewater parameters: NH4 +-N 40 mg / L, NO2 - -N 80 mg / L, Mn 2+ Concentration 40 mg / L, NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, MgSO4 25 mg / L. Control C / N = 0.5. After the influent solution is prepared, it is aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0114] During the reaction process, Mn in the biological manganese oxide 4+ participates in the manganeseammonia oxidation process as an electron acceptor and is reduced to Mn 3+ , while Mn 3+ has a strong redox ability and is also extremely unstable. It is quickly reduced to Mn during the reaction process 2 + ; The low-valent Mn 2+ also drives manganese autotrophic denitrification and reduces NO2 - -N as an electron donor.

[0115] After detection, in the 0 - 30 days, the present application has a significant effect on the removal of ammonia nitrogen and nitrite nitrogen in the simulated wastewater (see Table 1). The ammonia nitrogen removal rate exceeds 95%, and the nitrite nitrogen removal rate is close to 100%. Moreover, the accumulation of nitrate nitrogen in the effluent that appears in the conventional Anammox reactor is not found.

[0116] Table 1

[0117]

[0118] As a variation of this example, the inventors of the present application also tried to adjust the concentration of NH4 + -N and NO2 - -N in the influent every day, and the denitrification results are as Figure 8 shown.

[0119] Example 6 Treatment of simulated wastewater with a low carbon-nitrogen ratio II

[0120] This example is similar to Example 5, except that no exogenous Mn 2+ is added.

[0121] Introduce the simulated wastewater into the anaerobic microbial denitrification reactor after the successful construction of ABMP in Example 1 as an example for denitrification treatment.

[0122] The reactor operates continuously with a hydraulic retention time of 24 h, and the water temperature is maintained at 33°C ± 1°C. The simulated wastewater enters the reactor through the inlet pipe by a peristaltic pump and undergoes denitrification through the interaction of anaerobic denitrifying microorganisms and ABMP in the reactor.

[0123] Simulated wastewater parameters: NH4 + -N 40 mg / L, NO2 - -N 80 mg / L, NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, MgSO4 25 mg / L. Control C / N = 0.5. After the influent solution is prepared, it is aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0124] During the reaction process, Mn in the bio-manganese oxide 4+ participates in the manganese-ammonia oxidation process as an electron acceptor and is reduced to Mn 2+ ; the low-valent Mn 2+ drives manganese autotrophic denitrification again and reduces NO2 - -N as an electron donor. And during this process, no exogenous Mn 2+ is added, and denitrification is carried out only by relying on the interaction between anaerobic denitrifying microorganisms and ABMP.

[0125] After detection, no exogenous Mn 2+ is added, and denitrification is carried out only by relying on the interaction between anaerobic denitrifying microorganisms and ABMP. The ammonia nitrogen removal rate exceeds 90%, and the nitrite nitrogen removal rate exceeds 95%. At the same time, no nitrate nitrogen accumulation is seen in the effluent (as shown in Table 2). In addition, the concentration of manganese ions in the effluent decreases exponentially and stabilizes at 1-2 mg / L after 10 days, indicating that ABMP is fixed in the reactor and there will be no manganese leakage during the reaction, resulting in too high manganese ion concentration in the effluent and causing toxic effects. It can be seen that this application not only quickly constructs ABMP as the reaction center in the anaerobic reactor, but also, without adding exogenous Mn 2+ under the condition of, only relying on the interaction between denitrifying microorganisms and ABMP, completes the long-term manganese cycle and nitrogen conversion in the reactor, and has a stable and efficient treatment effect on nitrogen-containing simulated wastewater.

[0126] Table 2

[0127]

[0128] As a variation of this embodiment, the inventors of this application also tried to adjust the daily influent NH4 + -N concentration and NO2 - -N concentration. The denitrification results are as Figure 9 shown. It can be seen that this application quickly constructs ABMP as the reaction center in the anaerobic reactor and has a long-term and significant denitrification effect on high-load nitrogen-containing wastewater with different concentrations.

[0129] Example 7 Treatment of actual wastewater with a low carbon-nitrogen ratio - Part 1

[0130] Similar to Example 6, after the successful construction of the anaerobic microbial denitrification reactor of Example 1ABMP as an example, diluted actual domestic sewage was introduced into the reactor for denitrification treatment. The hydraulic retention time was 24 h, and the water temperature was maintained at 35 °C ± 1 °C. Wastewater parameters: NH4 + -N 38 ± 2 mg / L, NO2 - -N 41 ± 1 - 110 ± 12 mg / L. At the same time, trace elements required by microorganisms, namely NaHCO3 100 mg / L, KH2PO4 50 mg / L, CaCl2 20 mg / L, and MgSO4 25 mg / L, were added to the wastewater. Sodium acetate was added as an organic carbon source to control C / N = 0.5. After the influent solution was prepared, it was aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0131] After detection, during the 30 days of treatment, the present application had a significant effect on the removal of nitrite nitrogen and ammonia nitrogen in the actual wastewater. As Figure 10 shown in Table 3, without the addition of exogenous Mn 2+ and relying only on the interaction between anaerobic denitrifying microorganisms and ABMP for denitrification, the removal efficiency of nitrite nitrogen exceeded 95%, and the removal rate of ammonia nitrogen exceeded 90%. In addition, the concentration of manganese ions in the effluent decreased exponentially and stabilized at 1 - 2 mg / L after 10 d, indicating that ABMP was fixed in the reactor and there would be no manganese leakage during the reaction, resulting in excessive manganese ion concentration in the effluent and causing toxic effects. It can be seen that the present application relies on the interaction between denitrifying microorganisms and ABMP and has a high denitrification effect on wastewater containing ammonia nitrogen and nitrite nitrogen.

[0132] Table 3

[0133]

[0134] Example 8 Treatment of actual wastewater with a low carbon-nitrogen ratio - Part 2

[0135] Similar to Example 6, after the successful construction of the anaerobic microbial denitrification reactor of Example 1ABMP as an example, diluted actual domestic sewage was introduced into the reactor for denitrification treatment. The hydraulic retention time was 24 h, and the water temperature was maintained at 35 °C ± 1 °C. Wastewater parameters: NH4 + -N 42 ± 2 mg / L, NO3 --N is 37 ± 3 - 121 ± 11 mg / L. Meanwhile, trace elements required by microorganisms, namely 100 mg / L of NaHCO3, 50 mg / L of KH2PO4, 20 mg / L of CaCl2, and 25 mg / L of MgSO4, are added to the wastewater. Sodium acetate is added as an organic carbon source to control C / N = 0.5. After the influent solution is prepared, it is aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen in the solution (<0.3 mg / L).

[0136] After detection, during the 30 days of treatment, the present application has a significant effect on the removal of nitrate nitrogen and ammonia nitrogen in the actual wastewater. As Figure 11 shown in Table 4, without the addition of exogenous Mn 2+ and relying only on the interaction between anaerobic denitrifying microorganisms and ABMP for denitrification, the removal rates of nitrate nitrogen and ammonia nitrogen both exceed 90%. In addition, the concentration of manganese ions in the effluent decreases exponentially and stabilizes at 1 - 2 mg / L after 10 d, indicating that ABMP is fixed in the reactor and there will be no manganese leakage during the reaction, resulting in excessive manganese ion concentration in the effluent and causing toxic effects. It can be seen that the present application relies on the interaction between denitrifying microorganisms and ABMP and has a high denitrification effect on the actual wastewater containing ammonia nitrogen and nitrate nitrogen.

[0137] Table 4

[0138]

[0139] The above embodiments are only illustrative of the principles and effects of the present application and are not used to limit the present application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present application should still be covered by the claims of the present application.

Claims

1. A method for constructing an active biological manganese oxide pool (ABMP), characterized in that, It includes the following steps: S1. Cultivate anaerobic denitrifying granular sludge for 20 - 40 days, where the ratio of the first ammonia nitrogen concentration to the first nitrite nitrogen concentration in the influent is 1:1 - 1:3, and the cultivation water temperature is 28 - 32°C; S2. Add 15 - 25 mg / L of Mn with the influent water 2+ , and continue the cultivation for 20 - 40 days; S3. Increase the first ammonia nitrogen concentration and the first nitrite nitrogen concentration in the influent to the second ammonia nitrogen concentration and the second nitrite nitrogen concentration, increase the Mn 2+ concentration to 35 - 45 mg / L, increase the culture water temperature to 38 - 42 °C, and maintain the influent C / N = 2 - 3, and continue to culture for 20 - 40 days, where the second ammonia nitrogen concentration: the second nitrite nitrogen concentration = 1:1 - 1:

3.

2. The construction method of the active biological manganese oxide pool ABMP according to claim 1, characterized in that, Steps S1 - S3 further include maintaining a stirring speed of 30 - 60 rpm, and / or The first ammonia nitrogen concentration is 15 - 30 mg / L, and / or The second ammonia nitrogen concentration is 1.5 - 2.5 times that of the first ammonia nitrogen concentration.

3. The construction method of the active biological manganese oxide pool ABMP according to claim 1, characterized in that The relative abundance of anaerobic ammonium - oxidizing bacteria in the anaerobic denitrifying granular sludge accounts for 30 - 50% of the anaerobic denitrifying granular sludge.

4. The construction method of the active biological manganese oxide pool ABMP according to claim 1, characterized in that Step S2 further includes: adding 0.05 - 0.075 mg / L AHLs with the influent, and / or maintaining the influent C / N = 0.5 - 1.

5.

5. The construction method of the active biological manganese oxide pool ABMP according to claim 4, characterized in that, Step S3 further includes: increasing the influent AHLs concentration to 0.1 - 0.2 mg / L.

6. An active biological manganese oxide pool ABMP, characterized in that, It is prepared by the construction method of the active biological manganese oxide pool ABMP according to any one of claims 1 - 5.

7. An anaerobic denitrifying granular sludge reactor, characterized in that, The active biological manganese oxide pool ABMP is constructed by the construction method of the active biological manganese oxide pool ABMP according to any one of claims 1 - 5, or includes the active biological manganese oxide pool ABMP according to claim 6.

8. Application of the active biological manganese oxide pool ABMP according to claim 6 or the anaerobic denitrifying granular sludge reactor according to claim 7 in treating low - carbon - nitrogen - ratio wastewater.

9. The application according to claim 7, wherein The C / N in the low - carbon - nitrogen - ratio wastewater is ≤ 3.

10. A treatment method for wastewater with a low carbon-nitrogen ratio, characterized in that, It includes passing the low - carbon - nitrogen - ratio wastewater into the anaerobic denitrifying granular sludge reactor according to claim 7, and the C / N in the low - carbon - nitrogen - ratio wastewater is ≤ 3.

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