Denitrifying and alkali-removing liquid autotrophic denitrification bacteria-containing material, its preparation method and use

Abstract

The present invention discloses a denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material and its preparation method and application, the material contains a bacterial liquid including LH-B.0040 alkaliphilic halomonas with a deposit number of CGMCC NO: 16324, etc.; further comprising a sulfur-containing material, an iron-containing material, a colloidal material and trace elements. The material can quickly remove nitrates and nitrites and alkalinity in high-alkalinity salt-free or high-salt nitrogen-containing wastewater, without adding any carbon source, that is, to achieve the removal of total nitrogen, with high denitrification efficiency, strong salt tolerance, and alkali removal, low application cost, and application is not affected by the original system's own carbon source content. It can be added to any denitrification system, is simple to use, has a wide range of application processes, and can achieve extreme denitrification. It is suitable for the treatment of various high-alkalinity salt-free or high-salt nitrogen-containing wastewaters and has broad application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of biological denitrification of wastewater, in particular to a liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal and an application thereof. Background Art

[0002] Total nitrogen pollution caused by nitrates is a global environmental concern. Legislative bodies across the country have enacted laws and regulations to strictly limit nitrate levels in water bodies. my country is also continuously raising total nitrogen emission standards for urban and industrial wastewater treatment. Most sewage treatment plants with low C / N ratios still rely primarily on adding large amounts of carbon sources to remove nitrate. This not only aligns with the concept of green and environmentally friendly development, but also leads to a series of negative effects, such as significant sludge disposal costs, the risk of secondary pollution, and excessive carbon content in tailwater. Furthermore, sewage treatment plants generally suffer from substandard total nitrogen in tailwater. Research and development of low-carbon, or even carbon-free, autotrophic denitrification technologies for deep nitrogen removal is a hot topic in addressing this issue.

[0003] Autotrophic denitrification technologies already exist at home and abroad, and are mostly concentrated on various filter media, supporting filter equipment and fillers. Denitrification filter media mostly use high-temperature means to melt sulfur into a liquid state, and then mix it with other materials at high temperature to granulate into filter media particles. A large number of studies have shown that the denitrification rate and load of sulfur-based autotrophic denitrification composite filter media are positively correlated with their contact surface area. In order to improve the reaction efficiency, researchers have done a lot of work in terms of increasing the surface area by adjusting the size of the filter media and the pore-forming process. For example, publication number CN114644397A discloses a porous and high-strength autotrophic heterotrophic synergistic denitrification composite denitrification filter media and its preparation method; for example, publication number CN110104760B discloses a method of foaming and pore-forming a hot melt of sulfur and carbonate using a chemical or physical foaming method, and forming a large number of pores on the surface and inside of the filter media after cooling.

[0004] Common autotrophic denitrification fillers include foamed fillers and filler balls. For example, CN112499759B discloses a denitrification and dephosphorization foamed filler and its preparation method. This filler is produced through a high-temperature, high-pressure, supercritical foaming process. The foamed filler has a well-developed pore structure and can deeply remove nitrogen and phosphorus from wastewater. CN111137973A discloses centimeter-sized iron- and sulfur-based non-woven filler balls with denitrification properties.

[0005] Filter media or fillers are both complex to manufacture, and most utilize high-temperature, high-pressure, and hazardous processes. The material's contact surface area is limited, and while many methods for changing particle size or porosity can increase the contact area to a certain extent, these methods also present problems such as insufficient strength, small particles that are easily lost, and filter pool clogging. Furthermore, the filter pool itself has a low reuse rate, requires high equipment, and requires high investment costs, requiring large amounts of filter media to be added at once. These factors, along with the tendency for scaling on the filter media surface during long-term operation, hinder long-term use in many projects and limit their scope of engineering application. Therefore, developing an autotrophic denitrification technology material that is simple to add, has a wide range of applications, is not restricted by equipment, and can be directly applied to existing denitrification systems is an effective way to fundamentally address these technical shortcomings.

[0006] CN111056633A discloses a method for autotrophic denitrification using liquid and solid sulfur sources, as well as an autotrophic denitrification tank. This method provides more efficient mass transfer between liquid sulfur ions and solid sulfur, resolving traditional mass transfer issues and the potential for heterotrophic autotrophic denitrification, where the autotrophic bacteria may be replaced due to slow growth, leading to the system's inability to maintain long-term sustainability. However, the application of this patented technology requires certain equipment modifications, and the solid sulfur source bed component is a lossy component, fixedly installed in the tank body, making replenishment and replacement difficult. The sulfur source in solution also presents a risk of loss and requires additional alkalinity, making its applicability in high-salinity environments unknown. Summary of the Invention

[0007] In order to solve the above-mentioned problems in the prior art, the present invention provides a liquid autotrophic denitrification bacteria-containing material for denitrification and alkali removal. The material can be widely used in high-alkalinity, salt-containing, low-carbon or even carbon-free biochemical systems with a concentration of 0-15%. It can efficiently remove total nitrogen represented by nitrate nitrogen and nitrite nitrogen, and at the same time, it can reduce alkalinity without the need for additional carbon sources or additional structures. The addition is simple, and the material can quickly supplement and enrich the indigenous autotrophic denitrifying bacteria community, thereby achieving complete replacement or synergistic coexistence of heterotrophic and autotrophic denitrification, so that the total nitrogen in wastewater can be discharged in compliance with the standards at a low cost.

[0008] Another object of the present invention is to provide a preparation method and use of the aforementioned nitrogen dealkali liquid autotrophic denitrification bacteria-containing material.

[0009] The technical problem to be solved by the present invention is achieved by the following technical solution. The present invention is a liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal, which is characterized in that the material is composed of the following raw materials in the following weight ratios:

[0010] 100-200 parts of mixed bacterial liquid; 100-500 parts of sulfur-containing material;

[0011] 10-100 parts of iron-containing material; 15-30 parts of colloidal material;

[0012] 0.6-6 parts of trace elements;

[0013] The mixed bacterial solution is composed of the following raw materials in the following weight ratios:

[0014] LH-B.0040 alkaliphilic halomonas (CGMCC NO: 16324) Halomonas alkaliphila ) 50-100 copies of bacterial solution;

[0015] Paracoccus denitrificans ( Paracoccus denitrificans ) 30-80 parts of bacterial solution;

[0016] Thiobacillus denitrificans ( Thiobacillus denitrificans ) 30-80 parts of bacterial solution;

[0017] Brown hair fungus ( Leptothrix ) 10-50 copies of bacterial liquid.

[0018] The above-mentioned denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material has a further preferred technical solution: in the mixed bacterial liquid, the number of viable bacteria in each bacterial liquid is greater than 1×10 9 cfu / ml, and the OD600 value was greater than 2.

[0019] A further preferred technical solution of the above-mentioned liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal is that the sulfur-containing material is composed of the following raw materials in the following weight ratios:

[0020] Contains 50-100 parts of polysulfide;

[0021] 50-100 parts of micron or nanometer pyrite powder;

[0022] 40-80 parts of thiosulfate;

[0023] 10-20 parts of calcium polysulfide.

[0024] A further preferred technical solution of the above-mentioned liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal is that the iron-containing material is composed of the following raw materials in the following weight ratios:

[0025] 2-10 parts of micron or nanometer siderite powder;

[0026] 2-10 parts of iron powder;

[0027] 5-50 parts of ferrous sulfate.

[0028] A further preferred technical solution of the above-mentioned liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal is that the colloidal substance is composed of the following raw materials in the following weight ratios:

[0029] 5-10 parts of soy protein colloid;

[0030] 5-10 parts of starch liquid sol;

[0031] 5-10 parts of xanthan gum.

[0032] A further preferred technical solution of the above-mentioned liquid autotrophic denitrification bacteria-containing material for denitrification and alkali removal is that the trace elements are composed of the following raw materials in the following weight ratios:

[0033] MnCl2·7H2O 0.1-1 part;

[0034] H3BO3 0.1-1 part;

[0035] CoCl2·6H2O 0.1-1 part;

[0036] CuCl2·6H2O 0.1-1 part;

[0037] NiCl2·6H2O 0.1-1 part;

[0038] Na2Mo4·2H2O 0.1-1 parts.

[0039] The present invention also discloses a method for preparing a liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal as described in any one of the above technical solutions, which is characterized in that: a sulfur-containing material, an iron-containing material, a colloidal material, and trace elements are mixed and dispersed at high speed according to a mass ratio, and then mixed with a bacterial liquid according to a mass ratio to prepare the liquid denitrification bacteria-containing material.

[0040] The present invention also discloses a use of a liquid autotrophic denitrification bacteria-containing material for denitrification and alkali removal as described in any one of the above technical solutions, which is characterized in that: the denitrification bacteria-containing material is used to remove nitrate, nitrite and alkalinity in high-alkalinity wastewater; the high-alkalinity wastewater is high-alkalinity salt-free nitrogen-containing wastewater or high-alkalinity high-salt nitrogen-containing wastewater; the alkalinity of the high-alkalinity wastewater is greater than 400 mg / L; and the salinity of the wastewater is not more than 15% in terms of NaCl.

[0041] A further preferred technical solution of the above-mentioned use is that the dosage of the denitrifying bacteria-containing material is: material: total nitrogen = 3-20:1.

[0042] In the present invention, the alkaliphilic halomonas ( Halomonas alkaliphil a) The 16S rRNA sequence of LH-B.0040 is 1400 bp long. This strain has been deposited with the China General Microbiological Culture Collection, with the accession number CGMCC NO: 16324. The deposit address is the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, on August 20, 2018.

[0043] The liquid autotrophic denitrification bacteria-containing material for denitrification and alkali removal of the present invention has a simple addition method and can be directly added to activated sludge systems, biological filler systems, biological filter systems and other systems for biological denitrification. It has a wide range of applications, such as A / O, oxidation ditch, A2 / O, contact oxidation, hydrolysis+A / O, multi-stage anaerobic / anoxic, biological filter, BAF and other processes, and is applicable to activated sludge systems, biological filler systems, biological filter systems, high-density pool systems, etc.

[0044] Compared with the prior art, the present invention has the following beneficial technical effects:

[0045] (1) The material of the present invention can quickly remove nitrate, nitrite and alkalinity from high-alkalinity salt-free or salt-containing nitrogen-containing wastewater, and can achieve total nitrogen removal without adding any carbon source. It has high mass transfer efficiency and can achieve extreme denitrification. Its application is not affected by the carbon source content of the original system itself.

[0046] (2) The bacterial material of the present invention has a strong salt tolerance. When added to a non-salt-tolerant activated sludge system, it can enable the system to autotrophically denitrify and remove total nitrogen in a salinity range of 0%-15%, and has an alkali removal effect. The material contains a denitrifying bacterial community. After being added to the system, it can quickly start and transition the system, realize self-activation of the denitrification reaction process, and accelerate the denitrification reaction process; the material has a high mass transfer capacity and a high total nitrogen treatment load;

[0047] (3) The material of the present invention contains alkaliphilic Halomonas, which has a very good effect on alkalinity removal. At the same time, when combined with other materials, the denitrification effect is further improved.

[0048] (4) The material production process does not involve high temperature and high pressure, is less dangerous and easy to operate, and can be prepared into a homogeneous fluid liquid material that can be directly added and used in a variety of engineering scenarios without the need for structure modification, saving investment costs;

[0049] (5) Liquid autotrophic denitrification bacteria-containing materials carry their own charges and can couple with multiple biological electron carriers, quickly combining with carrier materials such as activated sludge, various biological fillers, and porous filter carriers, effectively preventing loss. At the same time, they can be used for bacterial attachment, effectively avoiding the phenomenon that when autotrophic and heterotrophic coexist, the autotrophic bacteria are difficult to compete with the heterotrophic bacteria, resulting in the weakening of the autotrophic bacteria flow performance.

[0050] (6) The denitrification and alkali removal liquid autotrophic denitrification bacteria-containing material of the present invention is added to any high alkalinity denitrification system with insufficient carbon source and salinity ≤15%, and can remove total nitrogen represented by nitrate nitrogen and nitrite nitrogen. It can remove total nitrogen to 1 mg / L by limiting denitrification. Compared with heterotrophic denitrification using glucose as the carbon source, the TN treatment load of autotrophic denitrification is increased by more than 25% at the same cost. When applied to the removal of total nitrogen from municipal wastewater, the cost is saved by more than 20% compared with the use of sodium acetate as an external carbon source.

[0051] (7) The present invention can be used for deep denitrification of tail water, which can effectively avoid secondary pollution of organic matter during tail water denitrification. It has low sludge production rate, cheap materials and is environmentally friendly, thus breaking through the technical bottlenecks and engineering difficulties of high-efficiency and low-cost deep denitrification. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is the total nitrogen removal effect diagram of the autotrophic denitrification bacteria-containing material;

[0053] Figure 2 This is a comparison chart of the biofilm formation effect of MBBR fillers. DETAILED DESCRIPTION

[0054] For a better understanding of the content of the present invention, the above description is further illustrated in conjunction with specific embodiments with reference to the accompanying drawings, but the present invention is not limited to the following embodiments.

[0055] Example 1: Liquid autotrophic denitrification bacteria-containing materials for denitrification and alkali removal and related experiments

[0056] 1. Screening of alkaliphilic Halomonas LH-B.0040

[0057] 1. Bacteria enrichment: The collected samples were washed repeatedly with 1% saline for 5 times to remove residual COD. The COD of the supernatant was determined to be less than 10 mg / L.

[0058] Prepare the following autotrophic denitrification culture medium: per liter: 0.4 g / L KNO₃, 1.5 g / L pyrite powder, 0.2 g / L sodium thiosulfate, 0.2 g / L calcium polysulfide, 1 g / L siderite powder, 0.5 g / L iron powder, 0.3 g / L ferrous sulfate, 0.5 g / L Na₂CO₃, 1% NaCl, 10 mL of trace element solution, pH 8-9. Trace element solution (1000 mL): 0.05 g / L MnCl₂·7H₂O, 0.05 g / L H₃BO₃, 0.2 g / L CoCl₂·6H₂O, 0.05 g / L CuCl₂·6H₂O, 0.05 g / L NiCl₂·6H₂O, 0.05 g / L Na₂Mo₄·2H₂O, 1 L water.

[0059] Add half the volume of denitrification culture medium to the anoxic reactor, connect the cleaned and standby salt-tolerant denitrification concentrated sludge to the reactor, add clean water to the system MLSS concentration of 3000-5000 mg / L, start the equipment stirring, control the dissolved oxygen to <0.5 mg / L, and culture at 25℃ for 24 hours. When the nitrate nitrogen and nitrite nitrogen contents are both <1 mg / L, it indicates that denitrification is complete. Stop stirring, let it settle for 2 hours, discard half of the supernatant, continue to add half of the denitrification culture medium, and start the stirring reaction. Repeat this for more than 10 times without adding any additional carbon source. The reaction time is gradually shortened to within 8 hours. The nitrate nitrogen and nitrite nitrogen contents in the effluent are both 1 mg / L, indicating that the denitrifying bacteria are successfully enriched.

[0060] 2. Isolation and identification of bacterial strains

[0061] The enriched autotrophic denitrifying bacteria solution is diluted in a gradient manner and then separated by streaking or smearing;

[0062] Autotrophic denitrification solid separation medium: each liter contains 0.4 g / L KNO3, 2 g / L pyrite powder, 0.3 g / L sodium thiosulfate, 0.2 g / L calcium polysulfide, 0.5 g / L siderite ore powder, 0.5 g / L iron powder, 0.5 g / L ferrous sulfate, 0.5 g / L Na2CO3, 10 g / L NaCl, 10 mL trace element solution, pH 8-9, and 20 g agar powder. Trace element solution (1000mL): MnCl2·7H2O 0.05 g / L, H3BO3 0.05 g / L, CoCl2·6H2O 0.2 g / L, CuCl2·6H2O 0.05 g / L, NiCl2·6H2O 0.05 g / L, Na2Mo4·2H2O 0.05 g / L. Boil to fully dissolve agar and pour into plate culture medium for later use.

[0063] The gradient diluted autotrophic denitrifying bacteria solution was spread onto a solid plate in a biosafety cabinet and cultured in an incubator at 37°C for 4 days. After colonies grew, single colonies were picked and streaked for isolation and purification until the bacteria on the plate were a single species.

[0064] The isolated single strain was sent to the China Agricultural Microbial Culture Collection Center for strain identification, and the single strain was identified as alkaliphilic Halomonas ( Halomonas alkaliphila ), named as alkaliphilic Halomonas LH-B.0040, and the preservation number is CGMCC NO:16324.

[0065] The alkaliphilic Halomonas LH-B.0040 strain of Example 1 and Thiobacillus denitrificans purchased from the Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences ( Thiobacillus denitrificans ), Paracoccus denitrificans ( Paracoccus denitrificans ) and iron-containing bacteria ( Gallionella ferruginea).

[0066] (1) Prepare the bacterial fermentation broth as follows:

[0067] Halomonas alkaliphila ( Halomonas alkaliphila ) Bacterial fermentation culture medium: KNO3 0.4g / L, pyrite powder 1g / L, sodium thiosulfate 0.3 / L, ferrous sulfate 0.5 / L, Na2CO3 1.5g / L, NaCl 10g / L, trace elements 10ml / L, pH 9.

[0068] Thiobacillus denitrificans ( Thiobacillus denitrificans ) Bacterial fermentation culture medium: KNO3 0.4g / L, pyrite powder 1.5g / L, sodium thiosulfate 0.3 / L, calcium polysulfide 0.2g / L, ferrous sulfate 0.3 / L, Na2CO3 0.5g / L, NaCl 20g / L, trace elements 10ml / L, pH 8.

[0069] Paracoccus denitrificans ( Paracoccus denitrificans ) Bacterial fermentation culture medium: KNO3 0.4g / L, pyrite powder 0.5g / L, sodium thiosulfate 0.3 / L, ferrous sulfate 0.3 / L, Na2CO3 1g / L, NaCl 20g / L, trace elements 10ml / L, pH 8.5.

[0070] Iron-containing bacteria ( Gallionella ferruginea) Bacterial fermentation culture medium: KNO3 0.4g / L, calcium polysulfide 0.2g / L, siderite powder 1.5g / L, iron powder 1g / L, ferrous sulfate 0.5 / L, Na2CO3 1g / L, NaCl 20g / L, trace elements 10ml / L, pH 8.5.

[0071] The composition of the above trace element solution (1000 mL) is: MnCl2·7H2O 0.03 g, H3BO3 0.03 g, CoCl2·6H2O 0.20 g, CuCl2·6H2O, NiCl2·6H2O 0.02 g, and Na2Mo4·2H2O 0.03 g.

[0072] (2) The above bacterial fermentation culture was placed in 500 ml triangular flasks and inoculated with LH-B.0040 alkaliphilic halomonas ( Halomonas alkaliphila )、Thiobacillus denitrificans( Thiobacillus denitrificans ), Paracoccus denitrificans ( Paracoccus denitrificans )、Iron-containing bacteria ( Gallionella ferruginea) Then culture at 35°C. After 48 hours of culture, transfer to a 1L culture flask, and after 48 hours of culture, transfer to a 5L culture container again and culture until OD600 reaches >2.

[0073] (3) The seed solution was further expanded to a 100 L fermenter and cultured for 24 h at a temperature of 35°C, a stirring speed of 100 rpm, and a dissolved oxygen concentration of 3.0 mg / L. Preparation was completed when the OD600 of the bacterial solution in the fermenter reached 2 or higher.

[0074] (4) Alkaliphilic Halomonas ( Halomonas alkaliphila ) 80 parts of bacterial solution, Paracoccus denitrificans ( Paracoccus denitrificans ) 50 parts of bacterial solution, Thiobacillus denitrificans ( Thiobacillus denitrificans ) 50 parts of bacterial liquid, brown fibrous fungus ( Leptothrix ) 20 parts of bacterial solution were mixed to obtain a mixed bacterial solution.

[0075] 100 parts of pyrite powder, 100 parts of polysulfide, 50 parts of thiosulfate, 10 parts of calcium polysulfide, 5 parts of siderite powder, 5 parts of iron powder, 5 parts of ferrous sulfate, 8 parts of soy protein colloid, 8 parts of starch lyosol, 8 parts of xanthan gum, 0.1 part of MnCl2·7H2O, 0.1 part of H3BO3, 0.1 part of CoCl2·6H2O, 0.1 part of CuCl2·6H2O, 0.1 part of NiCl2·6H2O, and 0.1 part of Na2Mo4·2H2O were added to a wet grinding device according to the mass ratio, 50% of water was added, stirred evenly, and ground for 45 minutes. The material passed through a 1000 mesh sieve with a pass rate of more than 95% and a particle size of less than 15 microns. The ground material was pumped into a stirring tank, and the mixed bacterial solution prepared in Example 3 was added to the stirring tank and stirred for 60 minutes to disperse and mix evenly, thereby obtaining a liquid autotrophic denitrification bacterial material.

[0076] Prepare a 75mg / L nitrate-nitrogen base solution. Take ordinary activated sludge and wash it repeatedly five or more times to remove residual COD, nitrogen, and other elements. Prepare three 1L stirring apparatuses, each containing 200ml of cleaned activated sludge and 400ml of nitrate-nitrogen base solution, for a total effective volume of 600ml. The system sludge concentration is approximately 3000mg / L, the nitrate-nitrogen concentration is 50mg / L, the pH is 9.0, and the alkalinity is 550mg / L.

[0077] The experiment involved setting up a control group (1#) with denitrification using a carbon source, and a test group (2#) with denitrification using a liquid autotrophic denitrification agent without any additional carbon source. The ratio of carbon source and liquid autotrophic denitrification agent to nitrate nitrogen was 8:1. Both units were set at a speed of 200 rpm and a constant temperature of 28 ± 0.5°C. Water was changed daily, and pH was not adjusted during the process.

[0078] The test results are shown in Table 1 (TN represents nitrate nitrogen + nitrite nitrogen): The denitrification efficiency of the control group gradually decreased with the number of trials. This was mainly because the added carbon source was gradually used for bacterial growth, while the carbon source used for heterotrophic denitrification gradually decreased. At the same time, heterotrophic denitrification produces alkalinity, which increases the alkalinity of the wastewater. High alkalinity has an inhibitory effect on heterotrophic denitrifying bacteria to a certain extent. In the experimental group, however, with the addition of liquid autotrophic denitrification bacteria-containing materials, the denitrification efficiency gradually increased, and the alkalinity in the water gradually decreased, indicating that the liquid autotrophic denitrification materials have a good denitrification effect and can remove alkali.

[0079] Table 1: Test data of denitrification and dealkali removal function of liquid denitrification bacteria-containing materials

[0080]

[0081] 5. Salt tolerance and denitrification performance test

[0082] The experiment not only examined the salt tolerance of the liquid autotrophic denitrification bacteria-containing material, but also examined the salt tolerance and simultaneous denitrification and denitrification performance.

[0083] Prepare a 75mg / L nitrate nitrogen basic solution. Take ordinary non-salt-tolerant heterotrophic denitrification activated sludge (sludge from the anoxic tank of a municipal sewage treatment plant, with a salinity tolerance of <2%), and wash it repeatedly with tap water for more than 5 times to remove the COD and nitrogen residues in the sludge before use. Prepare two 1L devices, each containing 200ml of activated sludge and 400ml of nitrate nitrogen basic solution, with a total effective volume of 600ml. The sludge concentration of the system is about 3000mg / L, and the nitrate nitrogen concentration is 50mg / L. pH 9.0, alkalinity 550mg / L. Add sodium chloride to supplement the salinity, starting from 1% salinity, and gradually increase to 15% and above according to a 1% salinity gradient.

[0084] The experiment was set up in parallel, and the liquid autotrophic denitrification bacteria-containing material was added at a ratio of 10:1 to total nitrogen, and no additional carbon source was added.

[0085] The device is set to a speed of 200 r / min and a constant temperature of 28±0.5℃. After the nitrate nitrogen is completely removed, 400 ml of the nitrate nitrogen basic solution with sodium chloride is added. The salt concentration is increased by 1% compared with the previous gradient. The above steps are repeated until the denitrification efficiency is reduced.

[0086] The test results are shown in Table 2 (TN value is nitrate nitrogen + nitrite nitrogen value): As the salinity increases, the addition of liquid autotrophic denitrification materials can remove total nitrogen. When the salinity is increased to 16%, a large amount of nitrite still accumulates after 95 hours of reaction, indicating that the salinity inhibits the continued conversion of nitrite into nitrogen gas. Therefore, the liquid autotrophic denitrification bacteria-containing material can completely complete the denitrification reaction at a sodium chloride salinity of ≤15%.

[0087] Table 2: Test data of salt-tolerance denitrification performance of liquid denitrification bacteria-containing materials

[0088]

[0089] 6. Comparison of the efficiency of liquid autotrophic denitrification bacteria-containing materials with other materials

[0090] The test involved collecting commercially available autotrophic denitrification granules, grinding them into micron-level powders, and sieving them for comparison with the denitrification performance of the present invention's product. The materials were numbered 0-GP, 1-YS (the present invention's material), 2-LC, and 3-ZC, respectively. The test method was the same as in Example 5.

[0091] The test results are shown in Table 3. Starting with a low feed rate, the startup speed was very slow at low feed rates. However, increasing the feed ratio showed faster startup for both 0-GP and 1-YS (the material of the present invention). 1-YS achieved a TN removal rate of 94% upon startup, gradually increasing to over 99%. 3-ZC was subsequently started, but 2-LC showed no clear signs of startup. As the feed ratio decreased, the denitrification efficiency of the 0-GP system gradually decreased to zero. 1-YS (the material of the present invention) maintained good performance even at a feed ratio of 5:1, while the denitrification efficiency of 3-ZC decreased somewhat when the feed ratio was optimized to 5:1. Overall, comparing the four materials, the 1-YS material of the present invention showed a faster startup speed, achieved extreme nitrogen removal, and exhibited more stable TN removal.

[0092] Table 3

[0093]

[0094] 7. Deep denitrification of landfill leachate wastewater

[0095] Leachate comes from landfill storage areas, garbage storage pits of garbage incineration plants, and garbage compression and transfer stations. It has common characteristics such as complex and changeable water quality composition, high organic matter concentration, high ammonia nitrogen concentration, high color, high conductivity, high alkalinity, and contains toxic substances such as polycyclic aromatic hydrocarbons (PAHs), adsorbable organic halides (AOXs), and polychlorinated biphenyls (PCBs).

[0096] The treatment process is "primary A / O + secondary A / O + MBR + filter + ozone micro-nano flotation + O3 / H2O2 micro-nano catalytic oxidation + contact oxidation." Both A / O processes are operated using a mud membrane method. The liquid autotrophic denitrification bacteria-containing material of the present invention is added to the primary A and secondary A tanks instead of a carbon source. Compared with the traditional heterotrophic denitrification of two-stage A / O at an on-site sewage station, when the influent TN is 1500-1800 mg / L, the TN of the sewage station MBR effluent is 150-270 mg / L, while the TN of the pilot MBR effluent is reduced to below 50 mg / L. This indicates that the autotrophic denitrification material of the present invention and the wastewater's own COD form a heterotrophic and autotrophic synergistic enhanced denitrification system, reducing the amount of added carbon source and increasing the denitrification load. No alkalinity is added during the process, and the biochemical denitrification removal rate is increased from 84-88% at the original sewage station to 94-99%.

[0097] At present, the most common denitrification process is the A / O process. TN is basically denitrification with a carbon source added to the A pool, which requires the consumption of a large amount of carbon source. Improper control of the carbon source will also cause the COD effluent to exceed the standard and may inhibit the nitrification of the O pool.

[0098] Two A / O groups were set up in the experiment. The experimental group added a carbon source to pool A, and the control group added the liquid autotrophic denitrification bacteria-containing material of the present invention to pool A. The startup speed, operation effect and long-term operation stability of the material replacing the external carbon source in removing total nitrogen were investigated.

[0099] The test employed continuous operation, with an influent TN of ammonia nitrogen, a 2% sodium chloride salinity, and an ammonia nitrogen concentration of 50-100 mg / L. Tank A was dosed with cultured autotrophic denitrifying bacteria, with dissolved oxygen controlled at ≤0.5 mg / L. Biofilms were cultured on the ropes for 1-2 days. Tank O was dosed with salt-tolerant nitrifying bacteria, and aeration was used to control dissolved oxygen at 2-6 mg / L. After 1-2 days of biofilm culture, continuous water inflow began. The system started at a low load and then gradually increased the load, achieving a nitrification solution reflow ratio of 300-600%.

[0100] Both groups of materials were added at a ratio of 6:1 to total nitrogen, and the control group was added with glucose as the carbon source. Maintaining 0.2kgTN / m 3 Start and operate at around d load, maintaining the same nitrification solution reflux ratio. Compare the total nitrogen removal loads of the two systems at the same cost and dosage.

[0101] (1) Comparison of startup, operation effect and operation stability between the experimental group and the control group

[0102] The experimental group used liquid autotrophic denitrification bacteria-containing materials as a carbon source. The denitrification system operated for over three months from startup. The combination of the materials and the bio-rope filler was effective, with no material residue detected in the effluent. The experimental group system started up quickly and operated stably for about a week. During normal operation, total nitrogen levels in the denitrification section remained at a low level of ≤5. When the total nitrogen concentration in the influent increased, stability was quickly restored. Ammonia nitrogen removal in the control group started up faster, but nitrate accumulated initially. Total nitrogen removal remained stable for about a week, but after one month of operation, nitrate and nitrite began to accumulate, indicating poor operational stability.

[0103] (2) Comparison of total nitrogen load between the experimental group and the control group at the same cost

[0104] The influent ammonia nitrogen was 60-68 mg / L, which was converted into nitrate nitrogen and nitrite nitrogen after nitrification and returned to pool A for denitrification after 3-6 times. The TN removal load of pool A was investigated. The data of 15 days of operation are shown in Table 4: The data show that the control group had a slow startup speed and a low total nitrogen removal load under the set carbon source dosage. After startup, the operation was unstable, and nitrite nitrogen gradually accumulated, resulting in a gradual decrease in TN removal load to 0.05 kgTN / m 3 .d, the effluent ammonia nitrogen fluctuated within the range of ≤8 mg / L; while the TN removal load of the experimental group was stable at 0.18 kgTN / m 3 .d, the total nitrogen in the effluent of pool A was always ≤5mg / L, and the ammonia nitrogen in the effluent was stable at <1mg / L, indicating stable operation.

[0105] Table 4: Comparison of total nitrogen removal load between the experimental group and the control group

[0106]

[0107] IX. Application of Liquid Autotrophic Denitrification Bacteria-Containing Materials in High-Alkalinity Petrochemical Tail Water Containing PTA

[0108] RO concentrate produced by PTA petrochemical tail water has almost no biodegradable COD, making it difficult for MBBR fillers to form biofilms and causing severe sludge loss. At the same time, the alkalinity is as high as about 6000 mg / L. After aerobic aeration, the pH can rise to above 9.5. Under this pH condition, heterotrophic denitrification is difficult to operate. The high pH will inhibit heterotrophic denitrifying bacteria. Even if a carbon source with a high carbon-nitrogen ratio is added, there is still no obvious denitrification effect, resulting in excessive total nitrogen in the effluent, and even carbon source penetration, resulting in excessive effluent COD.

[0109] The autotrophic denitrification bacteria-containing material of the present invention is added to the anoxic tank, and the denitrification effect is as follows: Figure 1As shown: the total nitrogen removal rate is above 96.5%, and the effluent TN is ≤2mg / L. When TN=10-15mg / L, HRT≤2.0h; when TN=35-40mg / L, HRT=3.5-5.5h; when TN=50mg / L, HRT≤12h, and under different total nitrogen environments, the alkalinity reduction rate is more than 10%. This shows that the liquid autotrophic denitrification bacteria-containing material can operate normally under high alkalinity conditions above pH 9.5, the effect is stable, and the alkalinity can be removed; there is no need to add a carbon source, and there is no risk of carbon source penetration. The application of the material of the present invention also improves the biofilm effect of the system MBBR. Figure 2 : a is the MBBR filler biofilm formation situation of the material application system of the present invention, b is the MBBR filler biofilm formation situation of the original system.

[0110] Example 2, a liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal, the material is composed of the following raw materials in the following weight ratios:

[0111] 100 parts of mixed bacterial liquid; 100 parts of sulfur-containing material;

[0112] 10 parts of iron-containing material; 15 parts of colloidal material;

[0113] 0.6 parts of trace elements;

[0114] The mixed bacterial solution is composed of the following raw materials in the following weight ratios:

[0115] LH-B.0040 alkaliphilic halomonas (CGMCC NO: 16324) Halomonas alkaliphila ) 50 copies of bacterial solution;

[0116] Paracoccus denitrificans ( Paracoccus denitrificans ) 30 portions of bacterial suspension;

[0117] Thiobacillus denitrificans ( Thiobacillus denitrificans ) 30 portions of bacterial suspension;

[0118] Brown hair fungus ( Leptothrix ) 10 portions of bacterial liquid.

[0119] In the mixed bacterial solution, the number of viable bacteria in each bacterial solution is greater than 1×10 9 cfu / ml, and the OD600 value was greater than 2.

[0120] The sulfur-containing material is composed of the following raw materials in the following weight ratios:

[0121] Contains 50 parts of polysulfide;

[0122] 50 parts of micron or nanometer pyrite powder;

[0123] 40 parts of thiosulfate;

[0124] 10 parts of calcium polysulfide.

[0125] The iron-containing material is composed of the following raw materials in the following weight ratios:

[0126] 2 parts of micron or nanometer siderite powder;

[0127] 2 parts iron powder;

[0128] 5 parts of ferrous sulfate.

[0129] The colloidal substance is composed of the following raw materials in the following weight ratios:

[0130] 5 parts of soy protein colloid;

[0131] 5 parts of starch liquid sol;

[0132] 5 parts xanthan gum.

[0133] The trace elements are composed of the following raw materials in the following weight ratios:

[0134] MnCl2·7H2O 0.1 part;

[0135] 0.5 parts of H3BO3;

[0136] 0.5 parts of CoCl2·6H2O;

[0137] 0.5 parts of CuCl2·6H2O;

[0138] NiCl2·6H2O 0.5 parts;

[0139] 1 part of Na2Mo4·2H2O.

[0140] The preparation method of the denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material is as follows: sulfur-containing material, iron-containing material, colloidal material and trace elements are mixed at a high speed according to a mass ratio and then mixed with bacterial liquid according to a mass ratio to prepare the liquid denitrification bacteria-containing material.

[0141] The purpose of the denitrification and alkali removal liquid autotrophic denitrification bacteria-containing material is to apply the denitrification bacteria-containing material to remove nitrate, nitrite and alkalinity in high-alkalinity wastewater; the high-alkalinity wastewater is high-alkalinity salt-free nitrogen-containing wastewater or high-alkalinity high-salt nitrogen-containing wastewater; the alkalinity of the high-alkalinity wastewater is greater than 400 mg / L; and the salinity of the wastewater is not more than 15% in terms of NaCl.

[0142] The dosage of the denitrifying bacteria-containing material is: material: total nitrogen = 3:1; when used, the denitrifying bacteria-containing material is directly added to an activated sludge system, a biological filler system, a biological filter system or other systems used for biological denitrification; the applicable process of the denitrification system is selected from A / O, oxidation ditch, A2 / O, hydrolysis acidification, multi-stage anaerobic / anoxic or denitrifying biological filter process.

[0143] Example 3, a liquid autotrophic denitrification bacteria-containing material for denitrification and dealkali removal, the material is composed of the following raw materials in the following weight ratios:

[0144] 200 parts of mixed bacterial liquid; 500 parts of sulfur-containing material;

[0145] 100 parts of iron-containing material; 30 parts of colloidal material;

[0146] 6 parts of trace elements;

[0147] The mixed bacterial solution is composed of the following raw materials in the following weight ratios:

[0148] LH-B.0040 alkaliphilic halomonas (CGMCC NO: 16324) Halomonas alkaliphila ) 100 copies of bacterial solution;

[0149] Paracoccus denitrificans ( Paracoccus denitrificans ) 80 portions of bacterial suspension;

[0150] Thiobacillus denitrificans ( Thiobacillus denitrificans ) 80 portions of bacterial suspension;

[0151] Brown hair fungus ( Leptothrix ) 50 portions of bacterial liquid.

[0152] In the mixed bacterial solution, the number of viable bacteria in each bacterial solution is greater than 1×10 9 cfu / ml, and the OD600 value was greater than 2.

[0153] The sulfur-containing material is composed of the following raw materials in the following weight ratios:

[0154] Contains 100 parts of polysulfide;

[0155] 100 parts of micron or nanometer pyrite powder;

[0156] 80 parts of thiosulfate;

[0157] 20 parts of calcium polysulfide.

[0158] The iron-containing material is composed of the following raw materials in the following weight ratios:

[0159] 10 parts of micron or nanometer siderite powder;

[0160] 10 parts of iron powder;

[0161] 50 parts of ferrous sulfate.

[0162] The colloidal substance is composed of the following raw materials in the following weight ratios:

[0163] 10 parts of soy protein colloid;

[0164] 10 parts of starch liquid sol;

[0165] 10 parts of xanthan gum.

[0166] The trace elements are composed of the following raw materials in the following weight ratios:

[0167] 1 part of MnCl2·7H2O;

[0168] 1 part H3BO3;

[0169] CoCl2·6H2O 0.1 part;

[0170] 0.5 parts of CuCl2·6H2O;

[0171] 1 part NiCl2·6H2O;

[0172] 0.5 parts of Na2Mo4·2H2O.

[0173] The preparation method of the denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material is as follows: sulfur-containing material, iron-containing material, colloidal material and trace elements are mixed at a high speed according to a mass ratio and then mixed with bacterial liquid according to a mass ratio to prepare the liquid denitrification bacteria-containing material.

[0174] The purpose of the denitrification and alkali removal liquid autotrophic denitrification bacteria-containing material is to apply the denitrification bacteria-containing material to remove nitrate, nitrite and alkalinity in high-alkalinity wastewater; the high-alkalinity wastewater is high-alkalinity salt-free nitrogen-containing wastewater or high-alkalinity high-salt nitrogen-containing wastewater; the alkalinity of the high-alkalinity wastewater is greater than 400 mg / L; and the salinity of the wastewater is not more than 15% in terms of NaCl.

[0175] The dosage of the denitrifying bacteria-containing material is: material: total nitrogen = 20:1; when used, the denitrifying bacteria-containing material is directly added to an activated sludge system, a biological filler system, a biological filter system or other systems used for biological denitrification; the applicable process of the denitrification system is selected from A / O, oxidation ditch, A2 / O, hydrolysis acidification, multi-stage anaerobic / anoxic or denitrifying biological filter process.

Claims

1. A denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material, characterized in that: The material is composed of the following raw materials in the following weight ratios: 100-200 parts of mixed bacterial liquid; 100-500 parts of sulfur-containing material; 10-100 parts of iron-containing material; 15-30 parts of colloidal material; 0.6-6 parts of trace elements; The mixed bacterial solution is composed of the following raw materials in the following weight ratios: LH-B.0040 alkaliphilic halomonas (CGMCC NO: 16324) Halomonas alkaliphila ) 50-100 copies of bacterial solution; Paracoccus denitrificans ( Paracoccus denitrificans ) 30-80 parts of bacterial solution; Thiobacillus denitrificans ( Thiobacillus denitrificans ) 30-80 parts of bacterial solution; Brown hair fungus ( Leptothrix ) 10-50 parts of bacterial solution; The iron-containing material is composed of the following raw materials in the following weight ratios: 2-10 parts of micron or nanometer siderite powder; 2-10 parts of iron powder; 5-50 parts of ferrous sulfate; The colloidal material is composed of the following raw materials in the following weight ratios: 5-10 parts of soy protein colloid; 5-10 parts of starch liquid sol; 5-10 parts of xanthan gum.

2. The denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material according to claim 1, characterized in that: In the mixed bacterial solution, the number of viable bacteria in each bacterial solution is greater than 1×10 9 cfu / ml, and OD 600 The value is greater than 2.

3. The denitrification and alkali-removing liquid autotrophic denitrification bacteria-containing material according to claim 1, characterized in that: The trace elements are composed of the following raw materials in the following weight ratios: MnCl2·7H2O 0.1-1 part; H3BO3 0.1-1 part; CoCl2·6H2O 0.1-1 part; CuCl2·6H2O 0.1-1 part; NiCl2·6H2O 0.1-1 part; Na2Mo4·2H2O 0.1-1 parts.

4. A method for preparing a denitrification and dealkali-removing liquid autotrophic denitrification bacteria-containing material according to any one of claims 1 to 3, characterized in that: The sulfur-containing material, the iron-containing material, the colloidal material and the trace elements are mixed and dispersed at high speed according to the mass ratio, and then mixed with the bacterial liquid according to the mass ratio to prepare the liquid denitrification bacteria-containing material.

5. Use of the liquid autotrophic denitrification bacteria-containing material for denitrification and alkali removal according to any one of claims 1 to 3, characterized in that: Denitrifying bacteria-containing materials are applied to remove nitrate, nitrite and alkalinity in high-alkalinity wastewater; the high-alkalinity wastewater is high-alkalinity salt-free nitrogen-containing wastewater or high-alkalinity high-salt nitrogen-containing wastewater; The alkalinity of high-alkalinity wastewater is greater than 400 mg / L; the salinity of the wastewater is not more than 15% in terms of NaCl.

6. The use according to claim 5, characterized in that The dosage of denitrifying bacteria-containing materials is: material: total nitrogen = 3-20:

1.

7. The use according to claim 5 or 6, characterized in that: When in use, the denitrifying bacteria-containing material is directly added to an activated sludge system, a biological filler system, a biological filter system or other systems used for biological denitrification; the applicable process for the denitrification system is selected from A / O, oxidation ditch, A2 / O, hydrolysis acidification, multi-stage anaerobic / anoxic or denitrifying biological filter process.

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