Sewage biological agent and application thereof

Abstract

The invention provides a sewage biological agent and application thereof, the sewage biological agent is applied to high-ammonia-nitrogen low-carbon-nitrogen-ratio sewage treatment, and the sewage biological agent comprises the following components in parts by mass: 10-20 parts of a direct ammonia oxidizing bacteria mixture, 25-50 parts of zeolite and 40-50 parts of a slow-release carbon source. According to the nitrification-direct ammoxidation activated sludge obtained by applying the sewage biological agent, the living environment of microorganisms in the activated sludge is optimized, the activity is enhanced, the activated sludge is evolved into functional composite nitrification-direct ammoxidation activated sludge, and the nitrification-direct ammoxidation activated sludge is compact in morphology and good in settling performance and has excellent stability and impact resistance; the technical problem of impact of a high-ammonia-nitrogen environment on sludge performance in a common technology is effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of sewage treatment, and in particular to a sewage biological preparation and application thereof. Background Art

[0002] Due to the complexity of sewage characteristics and the limitations of treatment technology, the treatment of wastewater with high ammonia nitrogen and low carbon ratio has always been a major difficulty in the field of sewage treatment.

[0003] The concentration of ammonia nitrogen in high-ammonia-nitrogen-low-carbon ratio wastewater is higher, and high concentrations of ammonia nitrogen are toxic to microorganisms in activated sludge, destroying the integrity of microbial cell membranes and causing leakage of internal cell substances, thereby affecting the normal metabolism and function of cells and significantly reducing the activity of microorganisms. In contrast, filamentous bacteria have a certain tolerance to high ammonia nitrogen environments and can maintain their growth advantages in such environments. This growth trend tends to stimulate the proliferation and growth of filamentous bacteria in sludge systems, while excessive growth of filamentous bacteria will change the structure of the sludge, making it loose and reducing its density, thereby affecting the sedimentation performance of the sludge. Excessive ammonia nitrogen loads can also lead to the disintegration of sludge, that is, the microorganisms and organic matter in the sludge are no longer tightly combined, but dispersed in the water. This disintegration phenomenon will further aggravate the expansion and thinning of the sludge.

[0004] To avoid the above problems, traditional biochemical treatment methods such as nitrification-denitrification process usually require a higher carbon-nitrogen ratio and a large amount of aeration to maintain microbial activity. Under low COD conditions, sludge cultivation is difficult and excessive aeration can easily lead to sludge self-oxidation and dissolution, thereby affecting the sludge sedimentation performance. In addition, high ammonia nitrogen influent has an impact on the sludge system, which requires a long period of acclimation to adapt.

[0005] Based on the above, it is urgent to study a treatment method for high ammonia nitrogen and low carbon ratio wastewater to solve the above problems. Summary of the invention

[0006] The main purpose of the present invention is to provide a sewage treatment method and a bioreactor for direct ammonia oxidation coupled with autotrophic denitrification, so as to solve the technical problem of the impact of high ammonia nitrogen environment on sludge performance in the above-mentioned common technologies.

[0007] To achieve the above-mentioned purpose, the present invention provides a sewage biological preparation, which is applied to the treatment of high ammonia nitrogen and low carbon nitrogen ratio sewage. Its composition, by mass, includes: 10 to 20 parts of direct ammonia oxidizing bacteria mixture, 25 to 50 parts of zeolite, and 40 to 50 parts of slow-release carbon source.

[0008] Furthermore, the composition of the direct ammonia oxidizing bacteria mixture includes direct ammonia oxidizing bacteria, extracellular polymers, inert inorganic matter and a small amount of miscellaneous bacteria.

[0009] Furthermore, the high ammonia nitrogen and low carbon-nitrogen ratio sewage includes fertilizer production wastewater, monosodium glutamate manufacturing wastewater, coking industry wastewater, garbage leachate, coal gas production wastewater and livestock and poultry breeding wastewater. The ammonia nitrogen content in the high ammonia nitrogen and low carbon-nitrogen ratio sewage is 300-2000 mg / L, and the carbon-nitrogen ratio is less than 2.86.

[0010] Furthermore, the preparation of the direct ammonia oxidizing bacteria mixture comprises the steps of:

[0011] Inoculating activated sludge containing direct ammonia oxidizing bacteria into a reaction tank, introducing the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage into the reaction tank and adjusting the mass fraction of hydroxylamine therein to 0.005% to 1%, controlling the dissolved oxygen in the reaction tank to 2 to 5 mg / L, and the hydraulic retention time of the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage to 12 to 48 hours;

[0012] When the total nitrogen removal rate of the effluent is higher than 80%, the effluent mixture is centrifuged at a rotation speed of 6000-8000 r / min to obtain a solid product, which is the direct ammonia oxidizing bacteria mixture.

[0013] Furthermore, the direct ammonia oxidizing bacteria include one or more of Alcaligenes, Bacillus, Acinetobacter, Klebsiella, Pseudomonas and Rhodococcus.

[0014] Furthermore, the particle size of the zeolite is 50-100 um, the slow-release carbon source includes one or more of peat, rice husk, straw, and degradable plastic, and the particle size of the slow-release carbon source is not greater than 200 microns.

[0015] Furthermore, the sewage biological preparation also includes a binder, which includes one or more of gelatin, polyvinyl alcohol and / or sodium alginate, and the amount of the binder added is 2 to 5% of the total mass of the direct ammonia oxidizing bacteria mixture, the zeolite, and the slow-release carbon source.

[0016] Furthermore, the preparation of the sewage biological preparation comprises the steps of:

[0017] The direct ammonia oxidizing bacteria mixture, the slow-release carbon source, the zeolite and the binder are mixed in proportion, extruded and granulated, and then subjected to low-temperature drying to obtain the sewage biological preparation, wherein the particle size of the sewage biological preparation is 0.5 to 3 mm.

[0018] The present invention provides an application of a sewage biological agent as described in any one of the above items in a continuous flow reactor, comprising the steps of: putting the sewage biological agent into an aerobic section for treating high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage, controlling the dissolved oxygen content in the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage to be 1 to 3 mg / L, and obtaining treated sewage after hydraulic retention for 18 to 36 hours.

[0019] Furthermore, the dosage of the sewage biological agent is 5-50% of the pool capacity.

[0020] The beneficial effects of the present invention are as follows:

[0021] The present invention provides a sewage biological preparation, which is composed of a direct ammonia oxidizing bacteria mixture, zeolite, and a slow-release carbon source, wherein the direct ammonia oxidizing bacteria mixture can convert ammonia nitrogen (NH4 + ) is directly converted into nitrogen (N2), and has a high tolerance to ammonia nitrogen, and can quickly adapt to high ammonia nitrogen environments. The addition of slow-release carbon sources effectively improves the activity of direct ammonia oxidizing bacteria in low-carbon wastewater with a high ammonia nitrogen ratio. Direct ammonia oxidizing bacteria are in a dominant position in the competition with nitrifying bacteria, and the released carbon source can be directly used by direct ammonia oxidizing bacteria for denitrification. Zeolite has selective adsorption for ammonia nitrogen in sewage, which can greatly accelerate the enrichment of ammonia nitrogen on the surface of microbial preparations, increase the contact between ammonia nitrogen and direct ammonia oxidizing bacteria, and greatly improve the treatment efficiency.

[0022] Based on the overwhelming survival advantage, direct ammonia oxidizing bacteria proliferate rapidly and continuously desorb from sewage biological preparations into activated sludge; and with the metabolic degradation of ammonia nitrogen in sewage by direct ammonia oxidizing bacteria and the targeted adsorption of ammonia nitrogen by zeolite, the ammonia nitrogen concentration in the water body decreases, the living environment of microorganisms in activated sludge is optimized, and the activity is enhanced. Activated sludge evolves into functionally complex nitrification-direct ammonia oxidation activated sludge with dense morphology, good sedimentation performance, excellent stability and impact resistance, which effectively solves the technical problem of the impact of high ammonia nitrogen environment on sludge performance in commonly used technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the microscopic morphology of the sludge flocs formed in Example 2 of the present invention.

[0025] Figure 2 It is a schematic diagram of the microscopic morphology of the sludge flocs formed in Comparative Example 2 of the present invention.

[0026] Figure 3 Schematic diagram of the diversity of microbial analysis in Analysis Examples 1 to 3 of the present invention.

[0027] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the implementation methods and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that all directional indications (such as up, down, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, in the present invention, the descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0031] Furthermore, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0032] The invention provides a sewage biological preparation, which is applied to the treatment of sewage with high ammonia nitrogen and low carbon-nitrogen ratio, and comprises, by weight, 10 to 20 parts of a direct ammonia oxidizing bacteria mixture, 25 to 50 parts of zeolite, and 40 to 50 parts of a slow-release carbon source.

[0033] In some embodiments, high ammonia nitrogen and low carbon nitrogen ratio wastewater is widely derived from a variety of industrial production processes, including fertilizer production, monosodium glutamate manufacturing, coking industry, landfill leachate, coal gas production, livestock and poultry breeding, etc. The ammonia nitrogen concentration of these high ammonia nitrogen and low carbon nitrogen ratio wastewaters is usually high and the organic matter content is relatively low. The ammonia nitrogen content in the high ammonia nitrogen and low carbon nitrogen ratio wastewater is 300-2000 mg / L, and the carbon nitrogen ratio is less than 2.86.

[0034] The composition of the direct ammonia oxidizing bacteria mixture includes direct ammonia oxidizing bacteria, extracellular polymers, inert inorganic substances and a small amount of miscellaneous bacteria.

[0035] The preparation of the direct ammonia oxidizing bacteria mixture comprises the steps of:

[0036] S1. Inoculate activated sludge containing direct ammonia oxidizing bacteria into a reaction tank, introduce the high ammonia nitrogen and low carbon nitrogen ratio sewage containing 0.005% to 1% by mass of hydroxylamine into the reaction tank, control the dissolved oxygen in the reaction tank to 2 to 5 mg / L, and the hydraulic retention time of the high ammonia nitrogen and low carbon nitrogen ratio sewage is 12 to 48 hours.

[0037] In some embodiments, the mass fraction of hydroxylamine in the sewage may be 0.05% to 0.5%.

[0038] In some embodiments, the COD / ammonia nitrogen ratio can be adjusted to 10-20 by adding a carbon source before the wastewater enters the reaction tank.

[0039] Among them, direct ammonia oxidizing bacteria can include one or more of alcaligenes, Bacillus, Acinetobacter, Klebsiella, Pseudomonas and Rhodococcus.

[0040] The activated sludge of direct ammonia oxidizing bacteria comes from fertilizer production, monosodium glutamate manufacturing, coking industry, landfill leachate, coal gas production and livestock and poultry breeding wastewater biochemical treatment system.

[0041] S2. When the total nitrogen removal rate of the effluent is higher than 80%, the effluent mixture is centrifuged at a rotation speed of 6000-8000 r / min to obtain a solid product, which is the direct ammonia oxidizing bacteria mixture.

[0042] The present invention adopts an in-situ enrichment method to prepare a direct ammonia oxygen bacteria mixture with strong stability.

[0043] Zeolite has selective adsorption for ammonia nitrogen in sewage. On the one hand, it can accelerate the enrichment of ammonia nitrogen on the surface of direct ammonia oxidizing bacteria, increase the contact between ammonia nitrogen and direct ammonia oxidizing bacteria, and greatly improve the treatment efficiency. On the other hand, the addition of zeolite can adsorb ammonia nitrogen in sewage, thereby optimizing the living environment of microorganisms such as nitrifying bacteria, weakening the inhibitory effect of high ammonia nitrogen on traditional nitrifying bacteria, and achieving coordinated removal. Exemplarily, the particle size of zeolite can be 50 to 100 um.

[0044] The slow-release carbon source includes one or more of peat, rice husk, straw, and degradable plastic, which can be ball-milled and air-selected in sequence to prepare powder with a particle size distribution below 200um. The addition of the slow-release carbon source effectively improves the activity of direct ammonia oxidizing bacteria in low carbon-nitrogen ratio wastewater, and the released carbon source can be directly used by direct ammonia oxidizing bacteria for denitrification. Among them, the application of waste degradable plastic powder can realize the resource utilization of solid waste.

[0045] In some embodiments, the sewage biological preparation further includes a binder, which includes one or more of gelatin, polyvinyl alcohol and / or sodium alginate. The addition of the binder can consolidate the direct ammonia oxidizing bacteria mixture, zeolite and slow-release carbon source to achieve a close combination of the three.

[0046] In other embodiments, the preparation of the sewage biological preparation comprises the steps of:

[0047] The direct ammonia oxidizing bacteria mixture, the slow-release carbon source, the zeolite and the binder are mixed in proportion, extruded and granulated, and then subjected to low-temperature drying to obtain the sewage biological preparation, wherein the particle size of the sewage biological preparation is 0.5 to 3 mm.

[0048] The present invention also provides an application of the sewage biological agent as described in any one of the above items in sewage treatment, comprising the steps of: putting the sewage biological agent into the aerobic section for treating high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage, controlling the dissolved oxygen content in the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage to 1-3 mg / L, and obtaining treated sewage after hydraulic retention for 18-36 hours.

[0049] In some embodiments, when sewage biological agents are added to the aerobic section of high ammonia nitrogen and low carbon nitrogen ratio sewage treatment, the concentration of activated sludge in the aerobic section can be 3000-5000 mg / L.

[0050] Exemplarily, the activated sludge in the aerobic section can be inoculated into the aerobic section by activated sludge in a similar high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage biochemical system, or the sewage biological agent can be directly added into the aerobic section where the activated sludge is stored.

[0051] The sedimentation performance of sludge is closely related to the activity of microorganisms, mainly nitrifying bacteria. Activated sludge is an amorphous floc similar to alum flowers with a particle size of 200 to 1000 microns, which has good coagulation and sedimentation performance. The active microorganisms usually exist in the form of bacterial flocs, which are viscous masses formed by the polysaccharide substances secreted by bacteria, so that the bacteria have the ability to resist adverse external factors and facilitate the sedimentation and separation of activated sludge.

[0052] High concentrations of ammonia nitrogen have an inhibitory effect on the activity of nitrifying bacteria, while direct ammonia oxidizing bacteria have a high tolerance to ammonia. Combined with the use of slow-release carbon sources, the competitiveness of direct ammonia oxidizing bacteria in the aerobic stage is guaranteed, and direct ammonia oxidizing bacteria can achieve exclusive growth in high-ammonia nitrogen wastewater. In common technologies, the combination of anaerobic ammonia oxidation and aerobic / anaerobic digestion is considered to be an effective method for simultaneously removing organic matter and ammonia from high-ammonia nitrogen wastewater and recovering resources. However, excessive C / N ratios entering the anaerobic ammonia oxidation system can cause overgrowth of denitrifying bacteria, resulting in inhibition of the anaerobic ammonia oxidation process and failure of denitrification. Direct ammonia oxidation technology provides an alternative to the complex coupling process in the treatment of high-ammonia nitrogen wastewater, replacing it with a one-step aerobic process.

[0053] Based on the overwhelming survival advantage, direct ammonia oxidizing bacteria proliferate rapidly and continuously desorb from sewage biological preparations into activated sludge; and with the metabolic degradation of ammonia nitrogen in sewage by direct ammonia oxidizing bacteria and the targeted adsorption of ammonia nitrogen by zeolite, the ammonia nitrogen concentration in the water body decreases, the living environment of microorganisms in activated sludge is optimized, and the activity is enhanced. Activated sludge evolves into functionally complex nitrification-direct ammonia oxidation activated sludge with dense morphology, good sedimentation performance, excellent stability and impact resistance, which effectively solves the technical problem of the impact of high ammonia nitrogen environment on sludge performance in commonly used technologies.

[0054] And with the modification and evolution of activated sludge, this stable sludge system can maintain high treatment efficiency and stability in the treatment of high ammonia nitrogen and low carbon nitrogen ratio wastewater in the continuous flow reactor, reducing operating fluctuations; and this complex microbial community structure has a strong impact resistance to water quality changes (such as pH value, toxic substances, etc.), and can maintain a stable treatment effect to a certain extent.

[0055] In comparison, direct ammonia oxidizing bacteria in common technologies are heterotrophic bacteria. Current research is mainly focused on laboratory-scale high carbon-nitrogen ratio wastewater treatment. There is no relevant report on how to achieve Dirammox microbial enrichment and application in continuous flow reactors. Inoculating direct ammonia oxidizing bacteria in high carbon-nitrogen ratio wastewater will inevitably face problems such as difficult retention and low abundance. However, the present invention uses the method of preparing immobilized bacterial agents to compound slow-release carbon sources, zeolites and direct ammonia oxidizing bacteria into direct ammonia oxidizing bacteria agents, thereby achieving high abundance, long retention and sludge modification of direct ammonia oxidizing bacteria in continuous flow sewage.

[0056] The present invention simplifies the multi-stage treatment process in the commonly used technology into a single-flow process, and the effluent water quality meets the standards and the effect is stable, successfully realizing the simplification of operation management and the improvement of flexibility.

[0057] In some embodiments, the dosage of the sewage biological agent is 5-50% of the tank capacity.

[0058] For easier understanding, the following examples are given:

[0059] Example 1 Preparation of direct ammonia oxidizing bacteria agent

[0060] Inoculate activated sludge from the biochemical treatment section of coal chemical wastewater containing direct ammonia oxidizing bacteria into a reaction tank, introduce coal gasification wastewater into the reaction tank and adjust the mass fraction of hydroxylamine therein to 0.5%, adjust the COD / ammonia nitrogen to be greater than 10 by adding a carbon source before the wastewater enters the reaction tank, control the dissolved oxygen in the reaction tank to 2-5 mg / L, and the hydraulic retention time of the high-ammonia-nitrogen and low-carbon-nitrogen ratio wastewater is 24 hours;

[0061] When the total nitrogen removal rate of the effluent is higher than 80%, the effluent mixture is centrifuged at a rotation speed of 6000-8000 r / min to obtain a solid product, which is a direct ammonia oxidizing bacteria mixture.

[0062] A direct ammonia oxidizing bacteria mixture, zeolite and peat are mixed, wherein the mass proportions of the three are 25%, 35% and 40% respectively, mixed with a binder such as gelatin and sodium alginate, extruded into granules of 2 to 3 mm, and low-temperature dried to obtain a direct ammonia oxidizing bacteria agent.

[0063] Example 2 Continuous Flow Test

[0064] The influent water in this embodiment is taken from the gasification effluent of a coal chemical industry. The influent ammonia nitrogen concentration is 390.4-559 mg / L, the influent COD is 400-941.9 mg / L, and the COD / ammonia nitrogen is 1.87, which is a typical high ammonia nitrogen and low carbon nitrogen ratio influent water.

[0065] The inoculated sludge was taken from the aerobic end of the biochemical reaction pool of Tongmei Chemical Plant, and the inoculated sludge concentration of the SBR reactor was 4000 mg / L. The SBR reactor achieves biochemical treatment of wastewater by completing the basic processes of water inlet, aeration, sedimentation, drainage and standby in a single reaction pool in chronological order. The operation cycle of the SBR process includes water inlet process, aeration process, sedimentation process, drainage process and standby time. According to the denitrification characteristics of direct ammonia oxidizing bacteria, the multi-stage treatment process is simplified to a single-process process, retaining only the aerobic stage, and the DO of the aerobic stage is controlled at 2-3 mg / L. The specific operating parameters are shown in Table 1.

[0066] Table 1 Reactor initial operating parameters

[0067]

[0068] Comparative Example 1: Other parameters are consistent with those of Example 2, except that the zeolite in the direct ammonia oxidizer is replaced by sepiolite.

[0069] Comparative Example 2: Other parameters were consistent with those of Example 2, except that no direct ammonia oxidizing bacteria agent was added.

[0070] After stable operation, continuous sampling and tracking of ammonia nitrogen and total nitrogen in the inlet and outlet water were performed, and sludge samples of Example 2 and Comparative Example 2 were simultaneously obtained for microscopic morphology detection. The results are shown in Table 1. Figure 1 and Figure 2 shown.

[0071] Table 2 Ammonia nitrogen and total nitrogen removal rate results of Example 2 and Comparative Examples 1 to 2

[0072] Ammonia nitrogen removal rate (%) Total nitrogen removal rate (%) Example 2 97.13％ 80.15％ Comparative Example 1 86.35％ 71.42％ Comparative Example 2 60.23％ 2.35％

[0073] As can be seen from Table 1, the direct ammonia oxidizing bacteria agent prepared by in-situ enrichment of the direct ammonia oxidizing bacteria mixture in the activated sludge of the biochemical pool in the plant area and combining it with a slow-release carbon source and zeolite directly oxidizes ammonia into dinitro gas or nitrogen in the aerobic section. The selective adsorption of ammonia nitrogen by zeolite makes its ammonia nitrogen removal efficiency better than that of the direct ammonia oxidizing bacteria agent prepared by sepiolite, and increases the collision probability between the substrate ammonia nitrogen and the direct ammonia oxidizing bacteria. In Comparative Example 2, no direct ammonia oxidizing bacteria agent was added, and direct ammonia oxidizing bacteria could not be enriched in the conventional activated sludge system. Nitrate nitrogen was only converted from ammonia nitrogen by nitrifying bacteria, and nitrogen removal from the system was not achieved. Figure 1 and Figure 2 It can be seen that the sludge flocs in Comparative Example 2 are loose, and a large number of filamentous bacteria are exposed outside the flocs, while the sludge flocs in Example 2 are compact, with better flocculation and sedimentation performance, and can achieve efficient treatment of high ammonia nitrogen and low carbon nitrogen ratio sewage.

[0074] Analysis Example 1: Dosage of Hydroxylamine Compounds

[0075] In this embodiment, the inoculated sludge is taken to the aerobic end of a biochemical reaction tank of a sewage plant, and the inoculated sludge concentration of the SBR reactor is 500 mg / L, and the MLVSS / MLSS of the sludge is 0.49. The SBR reactor completes the basic processes of water intake, aeration, sedimentation, drainage and standby in a single reaction tank in chronological order to achieve biochemical treatment of wastewater. The operation cycle of the SBR process includes water intake process, aeration process, sedimentation process, drainage process and standby time.

[0076] In order to systematically evaluate the enrichment effect of hydroxylamine compounds on direct ammonia oxidizing bacteria, 4 sets of SBR reactors were set up to simulate enrichment tanks for testing, of which A0 was the blank group without hydroxylamine; the control group A1 had a hydroxylamine dosage of 0.002%; the experimental group A2 had a hydroxylamine dosage of 0.1%; and the control group A3 had a hydroxylamine dosage of 5%. The influent of this experiment was simulated wastewater. The water quality index range is approximately: NH4 + -N: 50~70mg / L, COD: 400~600mg / L.

[0077] The initial operating parameter settings of the reactor are shown in Table 3, where a peristaltic pump is used for water inlet during the water inlet stage, and the water inlet time is 10 minutes. During the aerobic stage, a stirrer is used to drive the stirring paddle for stirring, and the stirring speed is 120rpm. The dissolved oxygen in the process is controlled at 2-5mg / L. During the sedimentation stage, this stage is a static stage, and the stirrer and aeration pump do not work during the process. During the decanting stage, a peristaltic pump is used to discharge water. The decanter is lowered to the set height of the reactor to pump the clear liquid out of the reactor through the pump tube to complete the water discharge. After 7 cycles of stable operation, samples were sent for testing of NH4 + -Microbial diversity in N, TN and mixed solutions.

[0078] Table 3 Reactor initial operating parameters

[0079]

[0080] From Table 4, we can see that the experimental group A2 has a strong effect on NH4 + -N removal rates were 99.45%, higher than 96.08%, 13.08% and 95.82% of control group A1, A3 and blank group A0; the removal rate of TN in experimental group A2 was 92.83%, and that in control group A1 was 10.67%, while there was basically no TN removal in control group A3 and blank group A0. TN usually needs to be removed by denitrification under anoxic conditions, while A2 can achieve efficient removal of TN under aerobic conditions, which indirectly indicates that microbial flora with direct ammonia oxidation function are enriched in the system; while A1 failed to inhibit other types of microorganisms due to too low hydroxylamine concentration; A3 caused the death of microorganisms in the system due to too high hydroxylamine concentration.

[0081] Microbial diversity analysis was performed on samples from each group. Figure 3 , the circled mark is the abundance value of direct ammonia nitrogen bacteria Alcaligenes. Figure 3 It can be seen that the abundance of direct ammonia oxidizing bacteria Alcaligenes in the experimental group A2 increased from 0.023% in the blank group A0 to 60.307%, which was much higher than 0.191% in the control groups A1 and 0.076% in A3.

[0082] Table 4 NH4 in water under different dosage of hydroxylamine compounds + -N and TN

[0083] A0 A1 A2 A3 <![CDATA[Effluent NH4 + N (mg / L)]]> 2.51 2.35 0.45 39.68 Outlet TN (mg / L) 58.8 53.6 4.6 59.13

[0084] Analysis Example 2: Hydroxylamine Compound Types

[0085] In order to systematically evaluate the enrichment effect of hydroxylamine compound types on direct ammonia oxidizing bacteria, two sets of SBR reactors were set up to simulate enrichment tanks for testing, in which hydroxylamine sulfate was added to B1 and diethylhydroxylamine was added to B2. Except for the type of hydroxylamine compound, the operating parameters in this example were consistent with those of the test group A2 in Example 1.

[0086] Microbial diversity analysis was performed on samples from each group. Figure 3 .Depend on Figure 3 It can be seen that the abundance of direct ammonia oxidizing bacteria Alcaligenes in the B1 and B2 reactors increased from 0.023% of the blank group A0 to 53.819% and 78.963%, respectively, both achieving efficient enrichment of direct ammonia oxidizing bacteria.

[0087] Analysis Example 3: Influent COD / NH4+ -N

[0088] Evaluate influent COD / NH4 for the system + -N enrichment effect on direct ammonia oxidizing bacteria, two sets of SBR reactors were set up to simulate enrichment tanks for testing, and different ratios of COD / NH4 were configured by adjusting the COD content in the simulated wastewater. + -N influent, COD / NH4 of C1 influent + -N is 5; COD / NH4 of C2 influent + -N is 20. In this embodiment, the operating parameters are COD / NH4 + -N is inconsistent, and the other operating parameters are consistent with those of test group A2 in Example 1.

[0089] Microbial diversity analysis was performed on samples from each group. Figure 3 .Depend on Figure 3 It can be seen that the abundance of direct ammonia oxidizing bacteria Alcaligenes in the C1 reactor increased from 0.023% in the blank group A0 to 9.75%, which is much lower than 83.493% in C2. + -N can quickly increase the enrichment of direct ammonia oxidizing bacteria in the enrichment tank, thereby achieving stable supplementation of mainstream bacteria and realizing stable aerobic ammonia oxidation denitrification of the mainstream system.

[0090] The above technical solutions of the present invention are only preferred embodiments of the present invention, and the patent scope of the present invention is not limited thereto. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A sewage biological agent, characterized in that: It is used for the treatment of high ammonia nitrogen and low carbon nitrogen ratio sewage. Its composition, calculated by weight, includes: 10 to 20 parts of direct ammonia oxidizing bacteria mixture, 25 to 50 parts of zeolite, and 40 to 50 parts of slow-release carbon source.

2. The sewage biological preparation according to claim 1, characterized in that: The direct ammonia oxidizing bacteria mixture comprises direct ammonia oxidizing bacteria, extracellular polymers, inert inorganic substances and a small amount of miscellaneous bacteria.

3. The sewage biological preparation according to claim 2, characterized in that: The high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage includes fertilizer production wastewater, monosodium glutamate manufacturing wastewater, coking industry wastewater, garbage leachate, gas production wastewater and livestock and poultry breeding wastewater. The ammonia nitrogen content in the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage is 300-2000 mg / L, and the carbon-nitrogen ratio is less than 2.

86.

4. The sewage biological preparation according to claim 2, characterized in that: The preparation of the direct ammonia oxidizing bacteria mixture comprises the steps of: Inoculating activated sludge containing direct ammonia oxidizing bacteria into a reaction tank, introducing the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage into the reaction tank and adjusting the mass fraction of hydroxylamine therein to 0.005% to 1%, controlling the dissolved oxygen in the reaction tank to 2 to 5 mg / L, and the hydraulic retention time of the high-ammonia-nitrogen and low-carbon-nitrogen ratio sewage to 12 to 48 hours; When the total nitrogen removal rate of the effluent is higher than 80%, the effluent mixture is centrifuged at a rotation speed of 6000-8000 r / min to obtain a solid product, which is the direct ammonia oxidizing bacteria mixture.

5. The sewage biological preparation according to claim 4, characterized in that: The direct ammonia oxidizing bacteria include one or more of Alcaligenes, Bacillus, Acinetobacter, Klebsiella, Pseudomonas and Rhodococcus.

6. The sewage biological preparation according to claim 1, characterized in that: The particle size of the zeolite is 50-100 μm, the slow-release carbon source includes one or more of peat, rice husk, straw, and degradable plastic, and the particle size of the slow-release carbon source is no more than 200 μm.

7. The sewage biological preparation according to claim 6, characterized in that: The sewage biological preparation also includes a binder, which includes one or more of gelatin, polyvinyl alcohol and / or sodium alginate. The amount of the binder added is 2-5% of the total mass of the direct ammonia oxidizing bacteria mixture, the zeolite and the slow-release carbon source.

8. The sewage biological preparation according to claim 7, characterized in that: The preparation of the sewage biological preparation comprises the steps of: The direct ammonia oxidizing bacteria mixture, the slow-release carbon source, the zeolite and the binder are mixed in proportion, extruded and granulated, and then subjected to low-temperature drying to obtain the sewage biological preparation, wherein the particle size of the sewage biological preparation is 0.5 to 3 mm.

9. Use of the sewage biological preparation according to any one of claims 1 to 8 in a continuous flow reactor, characterized in that: The method comprises the following steps: putting sewage biological preparation into an aerobic section for treating sewage with high ammonia nitrogen and low carbon nitrogen ratio, controlling the dissolved oxygen content in the sewage with high ammonia nitrogen and low carbon nitrogen ratio at 1-3 mg / L, and obtaining treated sewage after hydraulic retention for 18-36 hours.

10. The use of the sewage biological preparation in a continuous flow reactor according to claim 9, characterized in that: The dosage of the sewage biological agent is 5-50% of the pool capacity.

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