Active self-sustaining liquid denitrifying bacteria-containing material, its preparation and application

Abstract

The application discloses an active self-sustaining liquid denitrification bacteria-containing material and belongs to the technical field of wastewater biological denitrification. The bacteria-containing material comprises mixed bacteria liquid, sulfur-containing material, iron-containing material, colloidal material, plant fiber powder and trace elements, and the mixed bacteria liquid contains Halomonas titanicae LH-B.0026. The material can quickly remove nitrate and nitrite in low-alkalinity salt-free or high-salt nitrogen-containing wastewater, realizes self-balancing of multi-element electron cooperation, removes total nitrogen without supplement of any carbon source, has high denitrification efficiency, strong salt tolerance, low application cost, and is not affected by the carbon source content of an original system, can be added into any denitrification system, is simple to use, has wide application process range, can realize extreme denitrification, and is suitable for treatment of various salt-free or high-salt nitrogen-containing wastewater.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater biological denitrification, and particularly relates to a kind of active self-sustaining liquid denitrification bacteria-containing material, a preparation method and application thereof. BACKGROUND

[0002] The total nitrogen pollution problem caused by nitrate is a worldwide environmental problem. Various legislative organizations have introduced corresponding legal provisions to strictly limit the content of nitrate in water bodies. China has also continuously improved the total nitrogen emission standards for urban sewage and industrial wastewater treatment. Under the trend of low-carbon emission reduction, "carbon peak" and "carbon neutrality", most wastewater treatment plants with low C / N still mainly rely on adding a large amount of carbon source to achieve TN removal, which not only does not meet the green and environmentally friendly development concept, but also leads to a series of negative effects, such as a large amount of sludge disposal cost and secondary pollution risk, and tail water carbon exceeding standard. At the same time, there is a problem of tail water total nitrogen not meeting the standard in wastewater treatment plants. Research and development of autotrophic denitrification deep denitrification technology with low carbon or even no carbon is a hot spot for the above problems.

[0003] Denitrification technology with carbon source is a commonly used technology, but autotrophic denitrification or autotrophic-heterotrophic collaborative denitrification technology has not been widely applied due to the limitations of the application materials. However, existing autotrophic denitrification technologies at home and abroad are mainly focused on various filter materials, supporting filter equipment and fillers. The denitrification filter material is usually melted into a liquid state by high-temperature means, and then mixed with other materials at high temperature to form granules. A large number of studies have shown that the denitrification rate and load of sulfur-based autotrophic denitrification composite filter material are positively correlated with its contact surface area. In order to improve the reaction efficiency, researchers have done a lot of work on the size and pore forming process of the filter material to improve the surface area. For example, CN114644397A discloses a porous and high-strength autotrophic-heterotrophic collaborative denitrification composite denitrification filter material and its preparation method; and CN110104760B discloses a method of foaming and forming pores on the surface and inside of the filter material by foaming the hot melt of sulfur and carbonate.

[0004] Common autotrophic denitrification fillers are foaming fillers and filler balls. For example, CN112499759B discloses a denitrification and phosphorus removal foaming filler and its preparation method, which is prepared by high-temperature high-pressure supercritical foaming process to have developed pore structure and can deeply remove nitrogen and phosphorus in wastewater. CN111137973A discloses a centimeter-sized iron-based and sulfur-based denitrification functional non-woven fabric filler ball.

[0005] The filter material or filler has the problems of complex manufacturing process, high temperature and high pressure, limited contact surface area, and low utilization rate of filter pool, high equipment requirement, high investment cost, large one-time filter material addition, easy scaling on the surface of filter material during long-term operation, and narrow application range. Therefore, developing a self-sustaining autotrophic denitrification technology material with simple addition, wide application, no equipment limitation, and direct application in existing denitrification systems is an effective means to fundamentally solve the technical drawbacks.

[0006] CN111056633A discloses a liquid sulfur source and solid sulfur source autotrophic denitrification method and autotrophic denitrification pool. The liquid sulfur ion-solid sulfur element mass transfer is more sufficient, solving the traditional mass transfer problem and the problem that the slow reproduction of autotrophic bacteria group may be replaced to cause the system to be unable to be maintained for a long time. However, the application of the technology requires certain equipment modification, and the composition of the solid sulfur source bed is a loss part, which is fixedly installed in the pool body and is not easy to operate. The solution state part of the sulfur source also has the risk of loss, and the alkalinity needs to be supplemented. The applicability in high-salt environment is unknown. SUMMARY

[0007] To solve the above technical problems, the present application provides an active self-sustaining liquid denitrification bacteria-containing material, which can be widely applied to a biochemical system with 0-15% low alkalinity, low carbon, or even no carbon, and can efficiently remove total nitrogen represented by nitrate nitrogen and nitrite nitrogen, without additional carbon source, alkalinity, or additional structure. The material has simple addition, can quickly supplement and enrich indigenous autotrophic denitrification bacteria group, realizes the coexistence of heterotrophic and autotrophic denitrification, and enables the total nitrogen in wastewater to be discharged at a low cost.

[0008] The technical problem to be solved by the present application is solved by the following technical scheme. The present application is an active self-sustaining liquid denitrification bacteria-containing material, which is characterized in that the denitrification bacteria-containing material comprises the following components in mass ratio:

[0009] 100-200 parts of mixed bacteria solution; 150-300 parts of sulfur-containing material;

[0010] 10-100 parts of iron-containing material; 15-30 parts of colloidal material;

[0011] 30-150 parts of plant fiber powder; 0.6-6 parts of trace elements;

[0012] The mixed bacteria liquid comprises: 50-100 parts of fermentation liquid of Halomonas titanicae LH-B.0026 with the preservation number of CGMCC NO:22565, 30-80 parts of Paracoccus denitrificans bacteria liquid, 30-80 parts of Thiobacillus denitrificans bacteria liquid, and 10-50 parts of Leptothrix bacteria liquid. The viable bacterial count of each bacteria liquid is >1x10 9 cfu / ml, and the OD600 value is >2.

[0013] In the bacteria liquid of the application, the further preferred technical solution is:

[0014] The sulfur-containing material comprises 50-100 parts of sodium polysulfide, 50-100 parts of micron or nanometer grade pyrite powder, 40-80 parts of thiosulfate, and 10-20 parts of calcium polysulfide; the iron-containing material comprises 2-10 parts of micron or nanometer grade siderite stone powder, 2-10 parts of iron powder, and 5-50 parts of ferrous sulfate; the colloidal material comprises 5-10 parts of soybean protein colloid, 5-10 parts of starch liquid sol, and 5-10 parts of xanthan gum; the plant fiber powder comprises 10-50 parts of corn powder, 10-50 parts of yeast extract, and 10-50 parts of potassium humate; and the trace elements comprise 0.1-1 parts of MnCl2·7H2O, 0.1-1 parts of H3BO3, 0.1-1 parts of CoCl2·6H2O, 0.1-1 parts of CuCl2·6H2O, and 0.1-1 parts of Na2Mo4·2H2O.

[0015] The application further discloses a preparation method of the active self-sustaining liquid denitrification bacteria-containing material.

[0016] The application further discloses application of the active self-sustaining liquid denitrification bacteria-containing material or the active self-sustaining liquid denitrification bacteria-containing material prepared by the method.

[0017] In the above application, the wastewater alkalinity is less than 400 mg / L, and the salinity is less than or equal to 15% (calculated by NaCl); the denitrification bacteria-containing material is directly added into an activated sludge system, a biological filler system, a biological filter system or other systems for biological denitrification; the addition amount is that the ratio of the denitrification bacteria-containing material to total nitrogen is 3-20:1. The denitrification system is suitable for A / O, oxidation ditch, A2 / O, hydrolysis acidification, multi-stage anaerobic / anoxic or denitrification biological filter.

[0018] In the present application, the 16S rRNA sequence of Halomonas titanicae LH-B.0026 is 1359 bp in length, and the gene sequence and phylogenetic analysis tree are shown in Figures 1 and 2. Figure 1 The strain is preserved in the China General Microbiological Culture Collection Center, and the preservation number is CGMCC NO:22565.

[0019] The active self-sustaining liquid denitrification bacteria-containing material of the present application can be applied to the removal of nitrate and nitrite in low-alkalinity salt-free or high-salt nitrogen-containing wastewater with wastewater alkalinity less than 400 mg / L and wastewater salinity less than or equal to 15% (calculated by NaCl), without adding carbon source and alkalinity. The nitrate and nitrite removal process is realized by multi-electron cooperative self-balanced microbial low-carbon or carbon-free metabolism coupling.

[0020] The active self-sustaining liquid denitrification bacteria-containing material of the present application has an addition amount of material:total nitrogen = 3-20:1, and is added into any low-alkalinity carbon-deficient or carbon-free denitrification denitrification system with salinity less than or equal to 15% to remove total nitrogen represented by nitrate nitrogen and nitrite nitrogen, and can remove total nitrogen to 1 mg / L by extreme denitrification. Compared with heterotrophic denitrification using glucose as a carbon source, the autotrophic denitrification TN treatment load is increased by more than 25% at the same cost. When applied to municipal wastewater total nitrogen removal, the cost is saved by more than 20% compared with the use of sodium acetate as an external carbon source.

[0021] Compared with the prior art, the present application has the beneficial technical effects including:

[0022] (1) The material of the present application can quickly remove nitrate and nitrite in low-alkalinity salt-free or salt-containing nitrogen-containing wastewater and alkalinity, and can realize total nitrogen removal without adding any carbon source, has high mass transfer efficiency, can realize extreme denitrification, and the application is not affected by the carbon content of the original system itself.

[0023] (2) The active self-sustaining liquid denitrification bacteria-containing material of the present application introduces multi-electron donors to effectively balance the acid and alkalinity of the denitrification process, and effectively promotes the metabolic coupling of multi-microorganisms;

[0024] (3) The material of the present application contains a denitrification bacterial community, which can quickly realize the start-up and transition of the system after being added into the system, realize the self-activation of the denitrification reaction process, and accelerate the denitrification reaction process;

[0025] (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;

[0026] (5) The active self-sustaining liquid denitrification bacteria-containing material carries its own charge 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, it can provide a carrier for bacteria, effectively avoiding the coexistence of autotrophic and heterotrophic bacteria, where the autotrophic bacteria are difficult to compete with the heterotrophic bacteria, resulting in the weakening of the autotrophic bacteria flow performance.

[0027] (6) The present invention couples halophilic and salt-tolerant denitrifying bacteria with salt-tolerant materials, and can perform deep denitrification by autotrophic denitrification at a salinity of 0-15%. Currently, there is no report on such salt-tolerant performance in the field of autotrophic denitrification technology, and compared with the existing technology, it is at the leading level both domestically and internationally.

[0028] (7) The present invention can be used for deep denitrification of tail water, which can effectively avoid secondary pollution of organic matter during denitrification of tail water, has low sludge production rate, and uses cheap and environmentally friendly materials, thus breaking through the technical bottlenecks and engineering difficulties of high-efficiency and low-cost deep denitrification. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a phylogenetic tree diagram of Halomonas titanicae LH-B.0026 and known model bacteria constructed based on the maximum parsimony method of 16SrRNA. DETAILED DESCRIPTION

[0030] In order to better understand the content of the present invention, it is further illustrated in conjunction with specific examples, but the present invention is not limited to the following examples.

[0031] Example 1, denitrifying bacteria enrichment

[0032] The bacterial source sample, marine sludge, was washed repeatedly 5 times with 1% salt water to remove residual COD. The COD of the supernatant was measured to be less than 10 mg / L.

[0033] Autotrophic denitrification culture solution: 0.5 g / L KNO3, 0.5 g / L sodium polysulfide, 0.2 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 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 Na2Mo4·2H2O, 1 L water.

[0034] Heterotrophic denitrification culture solution: 10% NaCl, 0.25 mL / L glycerol, 0.25 g / L glucose, 0.05 mL / L methanol, 0.25 g / L proteose peptone, 0.15 g / L beef extract, 0.5 g / L KNO3, pH 7.0-8.0.

[0035] The half volume of denitrification culture solution was added to the anoxic reactor, and the standby salt-tolerant denitrification concentrated sludge was inoculated into the reactor. The system was supplemented with water to a MLSS concentration of 3000-5000 mg / L, the equipment was started to stir, the dissolved oxygen was controlled to be less than 0.5 mg / L, and the culture was carried out at 15-37°C for 8-48 h. When the nitrate nitrogen and nitrite nitrogen contents were both less than 1 mg / L, it was determined that the denitrification was complete, the stirring was stopped, the supernatant was discarded after 2 h of sedimentation, and the stirring reaction was started after the half volume of denitrification culture solution was added. Under such conditions, the reaction time was gradually shortened to 8 h, the nitrate nitrogen and nitrite nitrogen contents in the effluent were both 1 mg / L, and it was indicated that the enrichment of the denitrification bacterial flora was successful.

[0036] Example 2, strain isolation and identification

[0037] The two kinds of denitrification bacterial enrichment liquid enriched in Example 1 were gradient diluted, and then streaked or spread to separate;

[0038] Autotrophic denitrification solid separation medium: 0.4 g / L of KNO3, 2 g / L of sodium polysulfide, 0.5 g / L of pyrite powder, 0.3 g / L of sodium thiosulfate, 0.2 g / L of calcium polysulfide, 0.5 g / L of siderite stone powder, 0.5 g / L of iron powder, 0.5 g / L of ferrous sulfate, 0.5 g / L of Na2CO3, 20 g / L of NaCl, 10 mL of trace element solution, pH 8-9, 20 g of agar powder per liter. Trace element solution (1000 mL): 0.05 g / L of MnCl2·7H2O, 0.05 g / L of H3BO3, 0.2 g / L of CoCl2·6H2O, 0.05 g / L of CuCl2·6H2O, 0.05 g / L of Na2Mo4·2H2O, boil to dissolve the agar, pour the flat plate medium for standby.

[0039] Heterotrophic denitrification solid separation medium: glycerol 0.25 mL / L; glucose 0.25 g / L; methanol 0.5 mL / L; methylamine 0.2 mL / L; phenol 0.1 g / L; sodium acetate 0.25 mL / L; trisodium citrate 0.25 g / L; yeast powder 0.8 g / L; peptone 1.6 g / L; beef extract 1.6 g / L; K2HPO4·3H2O 1.0 g / L; KH2PO4 0.1 g / L; KNO3 0.4 g / L; NaCl 20 g / L; Na2SO4 20 g / L, 10 ml / L of trace elements, pH 7.5-8.0, 20 g / L of agar.

[0040] The two denitrifying bacteria solutions after gradient dilution were coated on the solid flat plate in the biological safety cabinet, and placed in the incubator at 37°C for 2-5 days. After the colonies grew, single colonies were picked and streaked for isolation and purification until the bacteria in the plate were single species.

[0041] The isolated single strain was sent to China Agricultural Microbial Culture Collection Center for strain identification. The single strain isolated from the heterotrophic denitrification enrichment liquid was identified as Halomonas titanicae LH-B.0026.

[0042] Example 3, preparation of mixed bacteria solution

[0043] (1) Halomonas titanicae LH-B.0026 bacteria liquid fermentation culture solution: glycerol 0.25 mL / L; glucose 0.25 g / L; methanol 0.5 mL / L; methylamine 0.2 mL / L; phenol 0.1 g / L; sodium acetate 0.25 mL / L; trisodium citrate 0.25 g / L; yeast powder 0.8 g / L; peptone 1.6 g / L; beef extract 1.6 g / L; K2HPO4·3H2O 0.5 g / L; KNO3 0.4 g / L; NaCl 20 g / L; Na2SO4 20 g / L, trace elements 10 ml / L, trace elements 10 ml / L, pH 7.5-8.0.

[0044] (2) Thiobacillus denitrificans bacteria liquid fermentation culture solution: KNO3 0.4 g / L, sodium polysulfide 1.5 g / L, pyrite powder 0.5 g / L, sodium thiosulfate 0.3 / L, calcium polysulfide 0.2 g / L, ferrous sulfate 0.3 / L, Na2CO3 0.5 g / L, NaCl 20 g / L, trace elements 10 ml / L, pH 7.5-8.5.

[0045] (3) Paracoccus denitrificans bacteria liquid fermentation culture solution: KNO3 0.4 g / L, sodium polysulfide 0.5 g / L, pyrite powder 0.3 g / L, sodium thiosulfate 0.3 / L, ferrous sulfate 0.3 / L, Na2CO3 1 g / L, NaCl 20 g / L, trace elements 10 ml / L, pH 8.0-8.5.

[0046] (4) Gallionella ferruginea bacteria liquid fermentation culture solution: KNO3 0.4 g / L, calcium polysulfide 0.2 g / L, pyrite powder 0.2 g / L, siderite stone powder 1.5 g / L, iron powder 1 g / L, ferrous sulfate 0.5 / L, Na2CO3 1 g / L, NaCl 20 g / L, trace elements 10 ml / L, pH 8.0-8.5.

[0047] (5) The above-mentioned culture medium was respectively filled into 500 ml of a triangular flask, and Halomonas titanicae LH-B.0026, Thiobacillus denitrificans, Paracoccus denitrificans and Gallionella ferruginea were respectively inoculated and cultured at 35 °C. After 48 h of culture, the culture was transferred into a 1 L culture bottle, and after 48 h of culture, the culture was again transferred into a 5 L culture container, and the culture was continued until the OD600 reached > 2.

[0048] In this embodiment, Thiobacillus denitrificans, Paracoccus denitrificans and Gallionella ferruginea were purchased from the China Agricultural Microbial Culture Collection Center.

[0049] (6) The seed liquid was further scaled up to 100 L of a fermentation tank for 24-48 h of culture, the culture temperature was 35 °C, the stirring speed was 100 rpm, and the dissolved oxygen was 2.0-4.0 mg / L. The preparation was completed when the OD600 of the bacterial liquid in the fermentation tank reached 2 or more.

[0050] (7) 80 parts of the bacterial liquid of Halomonas titanicae LH-B.0026, 50 parts of the bacterial liquid of Paracoccus denitrificans, 50 parts of the bacterial liquid of Thiobacillus denitrificans and 20 parts of the bacterial liquid of Leptothrix were mixed to obtain a mixed bacterial liquid.

[0051] Example 4, preparation of liquid autotrophic denitrification bacteria-containing material

[0052] 100 parts of sodium polysulfide, 100 parts of pyrite powder, 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 liquid sol, 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, and 0.1 part of Na2Mo4·2H2O are added into a wet grinding device according to a mass ratio, 50% of water is added, the mixture is stirred evenly, and the mixture is ground for 30-60 minutes. The material is 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 liquid prepared in Example 3 was added to the stirring tank and stirred for 60 minutes to disperse and mix evenly. Then, 10 parts of corn extract, 20 parts of yeast extract, 20 parts of molasses, 20 parts of potassium humate, 20 parts of potassium fulvic acid, and 50 parts of corn cob powder were added to the stirring tank and stirred to disperse and mix evenly. The active self-sustaining liquid denitrification bacterial material was prepared.

[0053] Example 5: Denitrification capacity test of liquid autotrophic denitrification bacteria-containing material

[0054] Prepare a 75mg / L nitrate-nitrogen base solution. Wash ordinary activated sludge at least five 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, and the pH is 7.5.

[0055] The experiment set up 1# as the control group, adding a carbon source for denitrification, and 2# as the experimental group, adding liquid autotrophic denitrification materials for denitrification, and no additional carbon source was added. The ratio of carbon source and liquid denitrification bacteria-containing materials to nitrate nitrogen was 8:1. The speed of both devices was set at 200r / min and the constant temperature was 28±0.5℃. The water was changed daily and the pH was not adjusted during the process.

[0056] The test results are shown in Table 1 (TN value is nitrate nitrogen + nitrite nitrogen value): The denitrification effect of the control group gradually decreased with the increase in the number of tests, mainly because the added carbon source was gradually used for bacterial growth, while the carbon source for heterotrophic denitrification gradually decreased. In the experimental group, the denitrification efficiency gradually increased with the addition of active self-sustaining liquid denitrification bacterial material, and the pH of the water did not change significantly, indicating that the liquid denitrification bacterial material has a good denitrification effect and can balance the pH.

[0057] Table 1: Denitrification function test data of liquid denitrification bacteria-containing materials

[0058]

[0059] Example 6, salt-tolerant denitrification performance test

[0060] The test investigates both the salt-tolerant performance of the liquid autotrophic denitrification bacteria-containing material and the denitrification and nitrogen removal performance under salt tolerance.

[0061] A 75 mg / L nitrate nitrogen base solution was prepared. Ordinary non-salt-tolerant heterotrophic denitrification activated sludge (sludge from an oxygen deficiency tank of a municipal wastewater treatment plant, salt tolerance <2%) was repeatedly washed with tap water for more than 5 times to remove the residual COD and N elements in the sludge and concentrated for standby use. Two 500 ml triangular bottles were prepared, each of which was filled with 200 ml of concentrated activated sludge and 400 ml of nitrate nitrogen base solution, with an effective volume of 600 ml, a sludge concentration of about 3000 mg / L, and a nitrate nitrogen concentration of 50 mg / L. Sodium chloride was added to supplement the salinity, starting from 1% salinity and gradually increasing to 15% and above in 1% salinity increments.

[0062] The test was set up in parallel, and the liquid autotrophic denitrification bacteria-containing material was added according to a total nitrogen ratio of 10:1, without additional carbon source.

[0063] The device was set to rotate at 200 r / min, and the temperature was kept at 28±0.5°C. After complete removal of nitrate nitrogen, 400 ml of nitrate nitrogen base solution supplemented with sodium chloride was added, and the salinity was increased by 1% compared to the previous gradient. The above steps were repeated until the denitrification efficiency decreased.

[0064] The test results are shown in Table 2 (TN value is the value of nitrate nitrogen + nitrite nitrogen): With the increase of salinity, the addition of liquid denitrification bacteria-containing material can remove total nitrogen. When the salinity is increased to 16%, there is still nitrite accumulation after 95 h of reaction, indicating that this salinity inhibits the conversion of nitrite to nitrogen. Therefore, the liquid denitrification bacteria-containing material can completely complete the denitrification reaction under ≤15% sodium chloride salinity.

[0065] Table 2: Liquid denitrification bacteria-containing material salt-tolerant denitrification performance test data

[0066]

[0067]

[0068] Example 7, comparison of liquid autotrophic denitrification bacteria-containing material performance

[0069] The test collected autotrophic denitrification granular products on the market, ground them into powder, and sieved them to micron-level fineness, and compared the denitrification performance with the product of the present application. The material numbers were 0-GP, 1-YS-1 (material of the present application), 2-LC, and 3-ZC. The test method was the same as Example 5.

[0070] The test results are shown in Table 3: from low dosage, the start-up speed is very slow, and after increasing the dosage, the start-up speed of 0-GP and 1-YS-1 (the material of the application) is faster, and the TN removal rate of 1-YS-1 is 95% after starting, and then gradually increases to more than 99%; 3-ZC starts later, but 2-LC has no obvious starting signs. With the gradual reduction of the material dosage, the denitrification effect of 0-GP gradually reduces to no effect, and 1-YS-1 (the material of the application) and 3-ZC are optimized to a dosage ratio of 5:1, and the denitrification is basically stable. Compared with the four materials, the start-up speed of 1-YS-1 material of the application is faster, the denitrification limit is higher, and the TN removal effect is more stable.

[0071]

[0072]

[0073] Example 8, resource utilization of waste salt and denitrification application of high-salinity wastewater with salinity ≥5%

[0074] After the treatment of high-salinity wastewater, waste salt is obtained by crystallization, and the total nitrogen (nitrate nitrogen) content is 1300-1500 mg / g, which is difficult to recycle. After the complete removal of nitrate nitrogen in the waste salt, evaporation and concentration crystallization can be carried out to realize the recycling and utilization of waste salt. The test adopts anoxic-flocculation process, and the anoxic tank is coupled with denitrification biological rope filler. The waste salt is dissolved into 10-15% salinity, and liquid autotrophic denitrification bacteria-containing material is continuously added into the anoxic tank. After anoxic denitrification, 150 mg / L of nitrate nitrogen can be removed to <1 mg / L, and the salt water obtained after flocculation and precipitation is clear and transparent. The salt obtained after evaporation and concentration crystallization meets the industrial salt standard.

[0075] Example 9, application in municipal nitrogen-containing wastewater in industrial park

[0076] The second-phase treatment scale of a sewage treatment plant in an industrial park in Jiangsu is about 50000 m3 / d, and the wastewater is composed of domestic wastewater and industrial wastewater. The water quality is greatly affected by the upstream enterprise water, and the COD fluctuates from dozens to hundreds of mg / L, and the TN fluctuates from dozens to 50 mg / L. The C:N of the raw water cannot stably meet the TN removal demand, and a large amount of carbon source needs to be additionally supplemented to ensure that the TN meets the first-level A discharge standard, and the treatment cost is high.

[0077] The "hydrolysis acidification-A / O-small A / O-magnetic coagulation-disinfection" process is used on site, and a large amount of carbon source is continuously added to maintain the total nitrogen in the effluent to meet the standard. The active self-maintaining liquid denitrification bacteria-containing material of the application is added to the A tank to replace the original system sodium acetate carbon source, the anaerobic retention time is 10 h, the A tank retention time is 6.5 h, the O tank retention time is 12.5 h, the raw water COD is 180 mg / L, the TN concentration is 50 mg / L, the TN in the A / O effluent is less than 15 mg / L, the ammonia nitrogen is less than 1 mg / L, the TOC in the effluent is less than or equal to 12 mg / L, and the COD is less than or equal to 35 mg / L, which meets the first level A discharge standard; under the test water quality conditions, the material and the total nitrogen removal ratio are 3-4, the treatment effect is stable, and the cost is saved by more than 20% compared with the sodium acetate carbon source; the data are shown in Table 4:

[0078] Table 4: Test data of municipal nitrogen-containing wastewater in an industrial area

[0079]

[0080] Example 10, application of material-coupled biological filler in A / O process

[0081] At present, the A / O process is mostly used for denitrification, and the TN is basically removed by adding carbon source for denitrification outside the A tank, which consumes a large amount of carbon source, and improper control of the carbon source will also cause COD burden and inhibition of the O tank nitrification. The liquid denitrification bacteria-containing material of the application is added to the A tank, and the material-coupled denitrification filler is used to investigate the starting speed, running effect and long-term running stability of the material for replacing the added carbon source for removing TN, and a heterotrophic denitrification process with the same process is set as a comparison.

[0082] The test is continuously run, the influent TN is ammonia nitrogen, the sodium chloride salinity is 2%, the ammonia nitrogen concentration is 50-100 mg / L, the autotrophic denitrification bacteria agent is added to the A tank, the stirring is controlled to be less than or equal to 0.5 mg / L, the biological rope is hung for 1-2 days for culture, the salt-tolerant nitrifying bacteria agent is added to the O tank, the aeration is controlled to be 2-6 mg / L, the biological rope is hung for 1-2 days for culture, the continuous influent is started, the load is gradually increased after low-load starting, and the nitrification liquid reflux ratio is 300-600%.

[0083] The two groups of materials are added according to the ratio of 6:1 to total nitrogen, and the carbon source for the control group is glucose. The load is started and run at about 0.2 kgTN / m 3 .d, the same nitrification liquid reflux ratio is maintained, and the total nitrogen removal load of the two is compared under the same cost addition amount.

[0084] (1) Comparison of starting, running effect and running stability of the experimental group and the control group

[0085] The experimental group used liquid denitrification bacteria-containing material to replace the carbon source. The denitrification system was started and maintained for more than three months. The material and biological rope filling combination worked well, and no material residue was detected in the effluent. The experimental group system can be quickly started and stabilized in about a week. The total nitrogen in the denitrification section can be maintained at a relatively low level of ≤5 during normal operation. When the influent total nitrogen concentration is increased, it can quickly recover to stability. The ammonia nitrogen removal in the control group starts quickly, but there is nitrate accumulation in the early stage. The total nitrogen removal is stable in about a week, but after running for a month, nitrate and nitrite start to accumulate, and the running stability is poor.

[0086] (2) Comparison of total nitrogen load between the experimental group and the control group

[0087] The influent ammonia nitrogen is 60-68 mg / L, which is converted to nitrate nitrogen and nitrite nitrogen after nitrification. After 3-6 times reflux to the A pool for denitrification, the TN removal load of the A pool is investigated. The running data for 15 days are shown in Table 5: The data show that under the set carbon source dosage, the control group has slow start-up speed, low total nitrogen removal load, and unstable operation after start-up. Nitrite nitrogen gradually accumulates, leading to a gradual decrease in TN removal load to 0.05 kgTN / m 3 .d, and the effluent ammonia nitrogen fluctuates in the range of ≤8 mg / L; while the TN removal load of the experimental group is stable at about 0.18 kgTN / m 3 .d, the total nitrogen in the A pool effluent is always ≤4 mg / L, the effluent ammonia nitrogen is stable <1 mg / L, and the operation is stable.

[0088] Table 5: Comparison of total nitrogen removal load between the experimental group and the control group

[0089]

[0090]

Claims

1. An active self-sustaining liquid denitrification bacteria-containing material, characterized in that: The denitrification bacteria-containing material contains the following components in mass ratio: 100-200 parts of mixed bacterial liquid; 150-300 parts of sulfur-containing materials; 10-100 parts of iron-containing materials; 15-30 parts of colloidal materials; 30-150 parts of plant fiber powder; 0.6-6 parts of trace elements; The mixed bacterial solution comprises: 50-100 parts of fermentation liquid of Halomonas titanicae LH-B.0026 with a deposit number of CGMCC NO: 22565, 30-80 parts of bacterial liquid of Paracoccus denitrificans, 30-80 parts of bacterial liquid of Thiobacillus denitrificans, and 10-50 parts of bacterial liquid of Leptothrix; the viable cell count of each bacterial liquid is greater than 1×10 9 cfu / ml, and OD 600 Value > 2; The sulfur-containing material comprises 50-100 parts of sodium polysulfide, 50-100 parts of micron or nanometer-sized pyrite powder, 40-80 parts of thiosulfate and 10-20 parts of calcium polysulfide; The iron-containing material comprises 2-10 parts of micron or nanometer siderite powder, 2-10 parts of iron powder and 5-50 parts of ferrous sulfate.

2. The active self-sustaining liquid denitrifying bacteria-containing material according to claim 1, characterized in that: The colloid material comprises 5-10 parts of soybean protein colloid, 5-10 parts of starch liquid sol and 5-10 parts of xanthan gum.

3. The active self-sustaining liquid denitrifying bacteria-containing material according to claim 1, characterized in that: The plant fiber powder contains 10-50 parts of corn flour, 10-50 parts of yeast extract and 10-50 parts of potassium humate.

4. The active self-sustaining liquid denitrifying bacteria-containing material according to claim 1, characterized in that: Trace elements include MnCl2·7H2 O 0.1-1 part, H3 BO3 0.1-1 part, CoCl2·6H2 O 0.1-1 part, CuCl2·6H2 O 0.1-1 part and Na2 Mo4·2H2 O 0.1-1 part.

5. The use of the active self-sustaining liquid denitrification bacteria-containing material according to any one of claims 1 to 4, characterized in that: The application uses the active self-sustaining liquid denitrifying bacteria-containing material to remove nitrate and nitrite in low-alkalinity salt-free or high-salinity nitrogen-containing wastewater.

6. The use according to claim 5, characterized in that The alkalinity of the wastewater is less than 400 mg / L, and the salinity is ≤15% in terms of NaCl. The denitrifying bacteria-containing material is directly added to an activated sludge system, a biological filler system or other systems used for biological denitrification, and the addition amount is denitrifying bacteria-containing material: total nitrogen = 3-20:

1.

7. The use according to claim 6, characterized in that The applicable processes for denitrification system are A / O, oxidation ditch, A 2 / O, hydrolysis acidification, multi-stage anaerobic / anoxic or denitrifying biological filter.

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