A microbial agent for treating acetate fiber wastewater, and its preparation method and application

Abstract

The present invention relates to the technical field of wastewater treatment, in particular to a microbial agent for treating acetate fiber wastewater, a preparation method and an application thereof, wherein the microbial agent is a salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent, comprising a composite microbial strain and an immobilized carrier material, wherein the composite microbial strain is prepared by mixing the bacterial liquid of Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus and Bacillus subtilis according to a volume ratio of 6:3:5:2:2. The strains of the microbial agent of the present invention are reasonably compatible, symbiotically coordinated, and non-antagonistic, and can grow in an acidic, high-salt acetate fiber wastewater environment and maintain strong biological activity, and are added to an acetate fiber wastewater biochemical treatment system, and have a good degradation effect on organic pollutants in wastewater under aerobic conditions, effectively solving the problem of low COD and ammonia nitrogen removal rates in the existing acetate fiber wastewater biochemical treatment system, improving effluent water quality, and promoting standard discharge.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and specifically relates to a salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent for treating acetate fiber wastewater, a preparation method and use thereof. Background Art

[0002] Acetate fiber is an important synthetic fiber, widely used in textiles, filter materials, cigarette filters and other fields. Acetate fiber wastewater (hereinafter referred to as acetate fiber wastewater) refers to industrial wastewater containing various organic and inorganic pollutants generated in the process of producing cellulose diacetate (hereinafter referred to as vinegar sheets) and its tow products. Acetate fiber wastewater has a high concentration of organic pollutants (COD, ammonia nitrogen, phosphorus, etc.), an acidic pH, and contains a certain concentration of difficult-to-degrade organic matter and heavy metals. At the same time, there are also high concentrations of inorganic salt ions, such as Cl - 、SO4 2- 、Na + , Ca 2+ Plasma. The water quality of acetate fiber wastewater is complex, and after being treated by the existing biochemical treatment system, the effluent is often difficult to meet the discharge standards.

[0003] Traditional biological denitrification is accomplished by autotrophic nitrification and denitrification. Nitrification is accomplished by the continuous action of ammonia oxidizing bacteria and nitrite oxidizing bacteria, and denitrification is composed of the continuous reaction of converting nitrate or nitrite into gaseous products, namely nitrogen or nitrous oxide. However, traditional nitrification and denitrification reactions require strict aerobic and anoxic conditions, which makes the operation more complicated and reduces the efficiency of the reaction.

[0004] With the continuous deepening of biological denitrification research, a type of bacteria with heterotrophic nitrification-aerobic denitrification function has been discovered. This type of bacteria has the characteristics of simultaneous nitrification and denitrification, can convert ammonia nitrogen into gaseous nitrogen, has unique advantages such as short generation time, fast denitrification rate, high activity and persistence, and has shown great denitrification potential, which provides a new way for biological denitrification of wastewater. In particular, the discovery of some strains that also have the ability to remove phosphorus can achieve the simultaneous and efficient removal of nitrogen, phosphorus and other pollutants in water under aerobic conditions.

[0005] Compared with traditional denitrification technology, heterotrophic nitrification-aerobic denitrification process is a new type of sewage biological treatment process with the characteristics of low carbon, high efficiency and economy. This process is more in line with the process improvement of sewage treatment plants, and heterotrophic nitrification-aerobic denitrification bacteria with the ability to remove nitrogen and phosphorus greatly improve the possibility of realizing this process. However, the heterotrophic nitrification-aerobic denitrification strains found so far are limited, and most of them are difficult to tolerate high-salinity, acidic acetate wastewater containing some difficult-to-degrade organic matter and heavy metals, and cannot achieve the improvement of wastewater treatment efficiency and treatment capacity.

[0006] Therefore, the art urgently needs to develop a heterotrophic nitrification-aerobic denitrification microbial agent with low investment, high purification efficiency, low energy consumption, low operation and management costs, and the ability to be used in acetate wastewater with high salt, acidity, high COD, and high ammonia nitrogen, so as to enhance the treatment capacity of the existing acetate wastewater biochemical system, improve the effluent quality, and promote compliance with emission standards. Summary of the invention

[0007] The purpose of the present invention is to provide a microbial agent for treating acetate fiber wastewater, a preparation method and an application thereof. The microbial agent has stable properties, high activity, can coexist with each other, does not antagonize each other, and synergistically degrades organic pollutants in acetate fiber wastewater efficiently, is easy to use and has good effects.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A microbial agent for treating acetate fiber wastewater is a salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent, comprising a composite microbial strain and an immobilized carrier material, wherein the composite microbial strain is prepared by mixing bacterial liquids of Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus holophaga and Bacillus subtilis.

[0010] Furthermore, the composite microbial strain is prepared by mixing bacterial liquids of Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus holophaga, and Bacillus subtilis in a volume ratio of 6:3:5:2:2.

[0011] The above strains of the present invention can be purchased from strain collection centers such as the China General Microbiology Center (CGMCC), the China Center for Type Culture Collection (CCTCC) and the American Type Culture Collection (ATCC).

[0012] Preferably,

[0013] The Pseudomonas stutzeri is Pseudomonas stutzeri CGMCC 1.10279;

[0014] The Pseudomonas aeruginosa is Pseudomonas aeruginosa CGMCC 1.10274;

[0015] The alcaligenes faecalis is Alcaligenes faecalis CGMCC 1.924;

[0016] The Paracoccus pantotrophus CGMCC 1.8851;

[0017] The Bacillus subtilis CGMCC 1.9083.

[0018] Wherein, the composite microbial strains and the immobilized carrier material are mixed in a weight ratio of 2:8.

[0019] Wherein, the immobilized carrier material is a composite material, and its preparation method comprises the following steps:

[0020] ① Take 20-30 parts of diatomaceous earth and pass it through a 200-mesh sieve, then add 5 mol / L hydrochloric acid solution to it and completely soak it, treat it at a constant temperature of 80-85°C for 85-90 minutes, and constantly stir, filter, wash it several times until it is neutral, and dry the filtered diatomaceous earth at 105°C to obtain dry diatomaceous earth;

[0021] ② Take 2 to 3 parts of crystalline aluminum chloride, add a sodium hydroxide solution with a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stir to make it uniform, and let it stand for 24 hours to obtain a mixed solution;

[0022] ③ Add the dried diatomaceous earth obtained in step ① to the mixed solution obtained in step ②, and add 18-22 parts of polyvinyl alcohol, 3-6 parts of calcium alginate, and 4-6 parts of maleic anhydride at the same time. Mix and stir evenly, let stand for 3-5 hours, and then dry and crush at 105°C to obtain the immobilized carrier material.

[0023] The method for preparing a microbial agent for treating acetate fiber wastewater of the present invention comprises the following steps:

[0024] (1) Preparation of composite microbial strains

[0025] Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis were cultured to a concentration of 1×10 8 ~1×10 9 The bacterial solution was prepared by mixing the mixture in a volume ratio of 6:3:5:2:2.

[0026] The preparation steps are as follows: inoculating each strain into a culture medium, respectively, expanding and culturing at 15-35° C. for 48-96 hours, and mixing the obtained microbial fermentation broths according to a ratio to obtain the microbial agent composite microbial strain; wherein the composition of the culture medium is 6-10 g / L glucose, 2-2.2 g / L urea, 0.8-1.0 g / L potassium dihydrogen phosphate, 0.1-0.2 g / L magnesium sulfate, and 8-12 g / L sodium chloride;

[0027] (2) Preparation of immobilized carrier material

[0028] ① Take 20-30 parts of diatomaceous earth and pass it through a 200-mesh sieve, then add 5 mol / L hydrochloric acid solution to it and completely soak it, treat it at a constant temperature of 80-85°C for 85-90 minutes, and constantly stir, filter, wash it several times until it is neutral, and dry the filtered diatomaceous earth at 105°C to obtain dry diatomaceous earth;

[0029] ② Take 2 to 3 parts of crystalline aluminum chloride, add a sodium hydroxide solution with a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stir to make it uniform, and let it stand for 24 hours to obtain a mixed solution;

[0030] ③ Add the clean diatomaceous earth in step ① to the mixed solution in step ②, and add 18-22 parts of polyvinyl alcohol, 3-6 parts of calcium alginate, and 4-6 parts of maleic anhydride at the same time, mix and stir evenly, let stand for 3-5 hours, and then dry and crush at 105°C to obtain the immobilized carrier material powder;

[0031] (3) The composite microbial strain and the immobilized carrier material are mixed in a weight ratio of 2:8 to obtain a microbial agent for treating acetate fiber wastewater.

[0032] The salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent of the present invention can be used in the treatment of cellulose acetate wastewater. When used, the microbial agent is placed in the biochemical treatment system of cellulose acetate wastewater.

[0033] Furthermore, the pH value of the microbial agent is 4 to 8 when used, and the optimal pH value is 5.5 to 7.5. The salinity when used is ≤ 7% (70000 mg / L). The use temperature is 10 to 50°C, and the optimal use temperature is 30°C.

[0034] When used, the microbial agent is directly added to the aeration tank of the acetate fiber wastewater biochemical treatment system. Before adding and using, the aeration tank needs to be aerated for 2 hours in advance, and the dissolved oxygen is controlled between 2mg / L and 4mg / L. The usage of the microbial agent is 1000ppm~5000ppm (1000g / m 3 ~5000g / m 3 ).

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The microbial agent used in the present invention for treating acetate fiber wastewater is prepared by compounding various heterotrophic nitrification-aerobic denitrification bacteria that are tolerant to high-salt and acidic environments to form a dominant bacterial community, and preparing a high-efficiency microbial preparation. A certain amount of the microbial preparation is added to the aerobic aeration section of the biochemical treatment system for high-salt and acidic acetate fiber wastewater, which can accelerate the degradation of pollutants by microorganisms, improve the biological treatment efficiency of the system, and ensure the stable operation of the system.

[0037] (2) The various strains of the microbial agent of the present invention are reasonably compatible, symbiotic and synergistic, and non-antagonistic. They can grow in an acidic, high-salt acetate wastewater environment and maintain strong biological activity. The operation is simple and can be directly added to the acetate wastewater biochemical treatment system. Under aerobic conditions, it has a good degradation effect on organic pollutants in the wastewater, effectively solving the problem of low removal rate of pollutants such as COD and ammonia nitrogen in the existing acetate wastewater biochemical treatment system, improving the effluent quality, and promoting compliance with discharge standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The following is a scanning electron microscope photograph of the finished microbial agent of the present invention (magnification: 5000 times).

[0039] Figure 2 The following is a scanning electron microscope photograph of the finished microbial agent of the present invention (magnification: 10,000 times). DETAILED DESCRIPTION

[0040] 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.

[0041] Example 1 Preparation of composite microbial strains

[0042] Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis were cultured to a concentration of 1×10 8 ~1×10 9 / mL of bacterial solution, and then mix them in a volume ratio of 6:3:5:2:2.

[0043] Among them, Pseudomonas stutzeri is Pseudomonas stutzeri CGMCC 1.10279; Pseudomonas aeruginosa is Pseudomonas aeruginosa CGMCC 1.10274; Alcaligenes faecalis is Alcaligenes faecalis CGMCC 1.924; Paracoccus pantotrophus CGMCC 1.8851; Bacillus subtilis CGMCC 1.9083.

[0044] The specific preparation steps are: inoculate each strain into the culture medium respectively, expand the culture at 35°C for 48 hours, and mix the obtained microbial fermentation broth according to a ratio to obtain the main material of the microbial agent; wherein the components of the culture medium are 10 g / L glucose, 2.0 g / L urea, 1.0 g / L potassium dihydrogen phosphate, 0.2 g / L magnesium sulfate, and 8 g / L sodium chloride.

[0045] Example 2 Synthesis of immobilized carrier material

[0046] The immobilized carrier material is a composite material, and the specific preparation steps are as follows:

[0047] (1) 40-50 g of diatomaceous earth was sieved through 200 mesh to obtain 30 g of diatomaceous earth, and then 200 mL of 5 mol / L hydrochloric acid solution was added to the diatomaceous earth to completely soak it, stirred at 85° C. for 90 min, and then filtered, washed with clean water until neutral, and the filtered diatomaceous earth was dried at 105° C. for 8 h to obtain dry diatomaceous earth;

[0048] (2) taking 2 g of crystalline aluminum chloride, adding a sodium hydroxide solution having a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stirring to make it uniform, and standing for 24 hours to obtain a mixed solution;

[0049] (3) Add the clean diatomaceous earth in step (1) to the mixed solution in step (2), and add 200 mg of polyvinyl alcohol, 45 mg of calcium alginate, and 50 mg of maleic anhydride at the same time. After mixing and stirring evenly, let stand for 3 hours, dry at 105° C., and grind to obtain an immobilized carrier material powder.

[0050] The composite material can fix microorganisms on its surface through adsorption. Unlike existing materials for immobilizing bacteria, the composite material has special biocompatibility and can highly support the continued growth and division of fixed bacteria on the material. Therefore, the bacteria that eventually grow on the material together with the material form an organic, complete micrometer-scale biochemical treatment unit that can quickly decompose pollutants in water through biodegradation and conversion. This organic biochemical treatment unit is significantly different from the usual activated sludge bacterial flocs in appearance, structure and performance.

[0051] The composite material carrier supports the growth of microorganisms on its surface. The sewage treatment unit formed is extremely small in size and has a huge specific surface area. It can not only ensure that the individual microorganisms in the bacterial group are in full contact with the water body, but the material itself also has a strong adsorption effect on pollutants in the water, forming an environment with relatively rich nutrients (pollutants) on the surface of the material, thereby greatly improving the microorganism's treatment efficiency of pollutants. Under the action of this material, biochemical treatment can efficiently remove pollutants such as organic matter, ammonia nitrogen, total nitrogen and phosphorus in sewage. Compared with the prior art, under the action of the composite material, microorganisms can more fully contact the water body, thereby greatly improving the efficiency of biochemical treatment.

[0052] Example 3 Preparation Example 1 of Salt-tolerant / Acid-tolerant Heterotrophic Nitrification-Aerobic Denitrification Microbial Agent

[0053] A salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent for treating acetate fiber wastewater, comprising a composite microbial strain and an immobilized carrier material. The composite microbial strain prepared in Example 1 and the immobilized carrier material prepared in Example 2 are mixed in a weight ratio of 2:8. The scanning electron microscope photograph of the prepared microbial agent is as follows: Figure 1 and Figure 2 shown.

[0054] Example 4 Preparation Example 2 of Salt-Tolerant / Acid-Tolerant Heterotrophic Nitrification-Aerobic Denitrification Microbial Agent

[0055] As in Example 1, Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis were cultured to a concentration of 1×10 8 ~1×10 9 The bacterial strains were prepared by mixing the bacterial liquid of 100 μg / mL in a volume ratio of 6:3:5:2:2. The bacterial strains were obtained by the same method as in Example 1.

[0056] The specific preparation steps are: inoculate each strain into the culture medium respectively, expand the culture at 25°C for 72 hours, and mix the obtained microbial fermentation broth according to a ratio to obtain the main material of the microbial agent; wherein the components of the culture medium are 8g / L glucose, 2.1g / L urea, 0.9g / L potassium dihydrogen phosphate, 0.15g / L magnesium sulfate, and 10g / L sodium chloride.

[0057] The preparation steps of the immobilized carrier material are as follows:

[0058] (1) 25 g of diatomaceous earth was obtained by passing it through a 200-mesh sieve, and then 200 mL of a 5 mol / L hydrochloric acid solution was added thereto to completely immerse the diatomaceous earth, and the diatomaceous earth was treated at a constant temperature of 80° C. for 90 min with continuous stirring, and then filtered and washed with clean water for multiple times until neutral, and the filtered diatomaceous earth was dried at 105° C. for 8 h to obtain dry diatomaceous earth;

[0059] (2) taking 2.5 g of crystalline aluminum chloride, adding a sodium hydroxide solution having a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stirring to make it uniform, and standing for 24 hours to obtain a mixed solution;

[0060] (3) Add the clean diatomaceous earth in step 1 to the mixed solution in step 2, and add 200 mg of polyvinyl alcohol, 40 mg of calcium alginate, and 50 mg of maleic anhydride. After mixing and stirring evenly, let stand for 4 hours, dry at 105° C., and grind to obtain an immobilized carrier material powder.

[0061] The composite microbial strain prepared above and the immobilized carrier material were mixed in a weight ratio of 2:8 to prepare a microbial agent.

[0062] Example 5 Preparation Example 3 of Salt-Tolerant / Acid-Tolerant Heterotrophic Nitrification-Aerobic Denitrification Microbial Agent

[0063] As in Example 1, Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis were cultured to a concentration of 1×10 8 ~1×10 9 The bacterial strains were prepared by mixing the bacterial liquid of 100 μg / mL in a volume ratio of 6:3:5:2:2. The bacterial strains were obtained by the same method as in Example 1.

[0064] The specific preparation steps are: inoculate each strain into the culture medium respectively, expand the culture at 25°C for 72 hours, and mix the obtained microbial fermentation broth according to a ratio to obtain the main material of the microbial agent; wherein the components of the culture medium are 6g / L glucose, 2.2g / L urea, 0.8g / L potassium dihydrogen phosphate, 0.1g / L magnesium sulfate, and 12g / L sodium chloride.

[0065] The preparation steps of the immobilized carrier material are as follows:

[0066] (1) 30 g of diatomaceous earth is obtained by passing it through a 200 mesh sieve, and then 200 mL of a 5 mol / L hydrochloric acid solution is added thereto to completely soak it, and the mixture is treated at a constant temperature of 80° C. for 90 min, and the mixture is continuously stirred, filtered, and washed multiple times until it is neutral, and the filtered diatomaceous earth is dried at 105° C. for 8 h to obtain dry diatomaceous earth;

[0067] (2) taking 3 g of crystalline aluminum chloride, adding a sodium hydroxide solution having a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stirring to make it uniform, and standing for 24 hours to obtain a mixed solution;

[0068] (3) Add the clean diatomaceous earth in step 1 to the mixed solution in step 2, and add 180 mg of polyvinyl alcohol, 60 mg of calcium alginate, and 40 mg of maleic anhydride. Mix and stir evenly, let stand for 5 hours, dry at 105° C. for 8 hours, and grind to obtain an immobilized carrier material powder.

[0069] The composite microbial strain prepared above and the immobilized carrier material were mixed in a weight ratio of 2:8 to prepare a microbial agent.

[0070] In order to highlight the beneficial effects of the present invention, the following comparative example experiments are given.

[0071] Comparative Example 1 Preparation of microbial agent

[0072] A different bacterial strain combination was selected from the present invention, and Pseudomonas, Nitrobacter, Denitrifying Coccus, and Bacillus were mixed and cultured in a volume ratio of 3:2:3:2 to a concentration of 1×10 8 ~1×10 9 / mL of bacterial solution.

[0073] The specific preparation steps are as follows: each strain is inoculated into a conventional culture medium (glucose 5 g / L, urea 1.5 g / L, potassium dihydrogen phosphate 0.6 g / L, magnesium sulfate 0.05 g / L, sodium chloride 5 g / L), and cultured at 25°C for 72 hours. The obtained microbial fermentation broths are mixed according to the ratio to obtain the main material of the comparison microbial agent.

[0074] The composite microbial strain prepared above is adsorbed on the activated carbon using conventional immobilized carrier materials, such as activated carbon, to prepare a microbial agent.

[0075] Comparative Example 2 Preparation of microbial agent

[0076] Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis in the present invention were used, but the volume ratio was changed to 3:4:2:1:0, and the culture was carried out to a concentration of 1×10 8 ~1×10 9 / mL of bacterial solution.

[0077] The specific preparation steps are as follows: inoculate each strain into a culture medium (glucose 7 g / L, urea 2 g / L, potassium dihydrogen phosphate 0.9 g / L, magnesium sulfate 0.15 g / L, sodium chloride 9 g / L), expand the culture at 30°C for 60 hours, mix the obtained microbial fermentation broth according to the ratio to obtain the main material of the comparison microbial agent.

[0078] The immobilized carrier material powder was prepared by the same method as in Example 2, and the composite microbial strains and the immobilized carrier material were mixed at a weight ratio of 2:8 to prepare a microbial agent.

[0079] Example 6: Test on salt / acid resistance of microbial agents

[0080] The salt / acid resistance test was performed using the microbial agent prepared in Example 3. 1 g of the microbial agent was inoculated into 100 mL of sterilized nutrient agar liquid culture medium and cultured at 160-180 r / min and 30-35° C. for 72 h. The OD 600 , in order to determine the growth of microorganisms under different salt contents of the microbial agent.

[0081] Different amounts of NaCl are added to the nutrient agar liquid medium in advance to prepare liquid medium with different salt contents, which are sterilized for use. Nutrient agar liquid medium ingredients: 10g peptone, 3g beef extract, pH 4.2-4.5, different amounts of NaCl are added according to the following salt contents, sterilized by high pressure steam at 121°C for 20 minutes, and then cooled for use.

[0082] Table 1 Determination of salt tolerance of microbial agents

[0083]

[0084] It can be seen from Table 1 that the microbial agent can still maintain the growth and reproduction of microorganisms in the nutrient agar liquid culture medium with higher salinity and acidic pH, has good salt / acid resistance, and can be fully applied to the treatment of high-salt and acidic cellulose acetate wastewater.

[0085] Example 7 Treatment of Cellulose Acetate Wastewater by Salt-Tolerant / Acid-Tolerant Heterotrophic Nitrification-Aerobic Denitrification Microbial Agents

[0086] The acetate wastewater in this embodiment is obtained by mixing the vinegar flake wastewater and desulfurization wastewater of a certain acetate fiber company in a ratio of 7:1, which is recorded as influent, and the main pollutants therein are detected.

[0087] Take 250mL of muddy water from the aerobic aeration section of the acetate fiber wastewater biochemical treatment system, centrifuge at 4000r / min for 5 minutes, pour out the supernatant, and retain the activated sludge. Use 250mL of the acetate fiber wastewater in this example to shake all the retained activated sludge and pour it into a 500mL triangular flask, add the microbial agent prepared in Example 3 to the acetate fiber wastewater at an addition amount of 5‰ (W / V), react at 180r / min, 30°C for 24h, and centrifuge the muddy water at 4000r / min for 5 minutes, detect the content of major pollutants in the supernatant, and record it as effluent; at the same time, centrifuge under the same conditions, retain the activated sludge, no longer add the microbial agent, repeat the above steps, run continuously, and investigate the stability of the microbial agent in the process of treating acetate fiber wastewater.

[0088] Table 2 Treatment effect of microbial agents on acetate fiber wastewater

[0089]

[0090] It can be seen from Table 2 that after the microbial agent in this embodiment is added to the acetate wastewater, it quickly takes effect after the initial (1 to 3 times) wastewater environment adaptation. After each batch of treatment, the various indicators of the sewage are significantly reduced, the COD removal rate is stable at more than 95%, the ammonia nitrogen and total nitrogen removal rates are stable at more than 90%, and the effluent pH is neutral. Referring to the relevant national environmental protection regulations, the above indicators of the treated sewage all meet the requirements of the "Comprehensive Wastewater Discharge Standard of the People's Republic of China" (GB8978-2002).

[0091] Example 8 Comparison of the effects of the microbial agent prepared by the present invention and other microbial agents on treating cellulose acetate wastewater

[0092] Take the microbial agents prepared in Example 4, Example 5, Comparative Example 1 and Comparative Example 2 respectively, and carry out the acetate wastewater treatment experiment according to the method of Example 7, that is, in the same acetate wastewater (vinegar wastewater and desulfurization wastewater of a certain acetate fiber Co., Ltd. are mixed in a ratio of 7:1), the same reaction conditions (take 250mL of mud water from the aerobic aeration section of the acetate wastewater biochemical treatment system, centrifuge at 4000r / min for 5 minutes, pour out the supernatant, and retain the activated sludge. Use this 250mL of acetate wastewater to shake all the retained activated sludge and pour it into a 500mL triangular flask, add the microbial agent to the acetate wastewater at an addition amount of 5‰ (W / V), react at 180r / min, 30°C for 24h, and centrifuge the mud water at 4000r / min for 5 minutes. The main pollutant content in the supernatant is detected) The test is carried out, and the removal rates of COD, ammonia nitrogen, total nitrogen and total phosphorus in the sewage after different treatments are recorded. The comparison results are shown in Table 3.

[0093] Table 3 Treatment effect of different microbial agents on acetate fiber wastewater

[0094]

[0095] It can be clearly seen from the above experimental comparison data that the microbial agents prepared in Examples 4 and 5 of the present invention have stable removal rates of various pollutants at a high level when treating acetate fiber wastewater, COD removal rate is stable at more than 95%, ammonia nitrogen and total nitrogen removal rates are stable at more than 95%, and total phosphorus removal rate is also more than 93%. However, due to the use of different bacterial strain combinations, bacterial strain ratios or immobilized carrier material formulations in Comparative Examples 1 and 2, the treatment effects are obviously poor, and the removal rates of various pollutants are lower than those in the embodiments of the present invention, which fully proves that only the specific bacterial strains selected by the present invention, compounded in a specific ratio, and combined with a specific immobilized carrier material formulation, can achieve the best effect in the treatment of acetate fiber wastewater.

[0096] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A microbial agent for treating acetate fiber wastewater, characterized in that: The invention is a salt-tolerant / acid-tolerant heterotrophic nitrification-aerobic denitrification microbial agent, comprising a composite microbial strain and an immobilized carrier material, wherein the composite microbial strain is prepared by mixing bacterial liquids of Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus holophaga and Bacillus subtilis in a volume ratio of 6:3:5:2:2; The immobilized carrier material is a composite material, and its preparation method comprises the following steps: ① Take 20-30 parts of diatomaceous earth and sieve it, then add hydrochloric acid solution to it and soak it completely, treat it at a constant temperature of 80-85°C, stir, filter, wash until neutral, and dry the filtered diatomaceous earth to obtain dry diatomaceous earth; ② Take 2 to 3 parts of crystalline aluminum chloride, add sodium hydroxide solution so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stir evenly, and let stand to obtain a mixed solution; ③ Add the dried diatomaceous earth obtained in step ① to the mixed solution obtained in step ②, and add 18-22 parts of polyvinyl alcohol, 3-6 parts of calcium alginate, and 4-6 parts of maleic anhydride at the same time. Mix and stir evenly, let stand, dry, and crush to obtain the immobilized carrier material.

2. The microbial agent for treating acetate fiber wastewater according to claim 1, characterized in that: The composite microbial strain and the immobilized carrier material are mixed in a weight ratio of 2:

8.

3. The method for preparing the microbial agent for treating acetate fiber wastewater according to claim 1 or 2, characterized in that: The following steps are involved: (1) Preparation of composite microbial strains Pseudomonas stutzeri, Pseudomonas aeruginosa, Alcaligenes faecalis, Paracoccus omnivorus, and Bacillus subtilis were inoculated into the culture medium respectively and cultured at 15-35°C and 180 r / min for 48-96 hours until the concentration reached 1×10 8 ~1×10 9 The obtained bacterial broths of the microorganisms are mixed in a volume ratio of 6:3:5:2:2 to obtain the composite microbial strain; (2) Preparation of immobilized carrier material ① Take diatomaceous earth and sieve it, then add hydrochloric acid solution to it and soak it completely, treat it at a constant temperature of 80-85°C, stir, filter, wash until it is neutral, and dry the filtered diatomaceous earth to obtain dry diatomaceous earth; ② Take crystalline aluminum chloride, add sodium hydroxide solution so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stir evenly, and let stand to obtain a mixed solution; ③ Add the dried diatomaceous earth obtained in step ① to the mixed solution obtained in step ②, and simultaneously add polyvinyl alcohol, calcium alginate and maleic anhydride, mix and stir evenly, let stand, dry and crush to obtain the immobilized carrier material; (3) The composite microbial strain and the immobilized carrier material are mixed in a weight ratio of 2:8 to obtain a microbial agent for treating acetate fiber wastewater.

4. The method for preparing the microbial agent for treating acetate fiber wastewater according to claim 3, characterized in that: In step (1), the components of the culture medium are 6-10 g / L glucose, 2-2.2 g / L urea, 0.8-1.0 g / L potassium dihydrogen phosphate, 0.1-0.2 g / L magnesium sulfate, and 8-12 g / L sodium chloride.

5. The method for preparing the microbial agent for treating acetate fiber wastewater according to claim 3, characterized in that: The specific method for treating diatomaceous earth in step (2) is to take 20 to 30 parts of diatomaceous earth and pass it through a 200-mesh sieve, then add 5 mol / L hydrochloric acid solution to completely soak it, treat it at a constant temperature of 80 to 85° C. for 85 to 90 minutes, and constantly stir, filter, wash it multiple times until it is neutral, and dry the filtered diatomaceous earth at 105° C. to obtain dry diatomaceous earth.

6. The method for preparing the microbial agent for treating acetate fiber wastewater according to claim 3, characterized in that: The preparation method of the mixed solution in step (2) is specifically as follows: take 2 to 3 parts of crystalline aluminum chloride, add a sodium hydroxide solution with a mass concentration of 15% so that the final molar ratio of aluminum chloride to aluminum hydroxide is 2:1, stir to make it uniform, and let it stand for 24 hours to obtain a mixed solution.

7. The method for preparing the microbial agent for treating acetate fiber wastewater according to claim 3, characterized in that: In the step (2), the dried diatomaceous earth obtained in step ① is added to the mixed solution obtained in step ②, and 18 to 22 parts of polyvinyl alcohol, 3 to 6 parts of calcium alginate, and 4 to 6 parts of maleic anhydride are added at the same time. The mixture is stirred evenly, and then allowed to stand for 3 to 5 hours, and then dried and crushed at 105° C. to obtain an immobilized carrier material.

8. Use of the microbial agent according to claim 1 or 2 in treating acetate fiber wastewater.

9. The use of the microbial agent according to claim 8 in treating acetate fiber wastewater, characterized in that: When using microbial agents, the pH is 4-8, the salinity is ≤7%, and the operating temperature is 10-50℃; When in use, the microbial agent is directly added to the aeration tank of the acetate fiber wastewater biochemical treatment system; before addition and use, the aeration tank needs to be pre-aerated for 2 hours, and the dissolved oxygen is controlled between 2mg / L and 4mg / L.

10. The use of the microbial agent according to claim 8 in treating acetate fiber wastewater, characterized in that: The usage of microbial agents is 1000ppm to 5000ppm.

Images