Process and application of a tandem biological trickling filter tower with a combined bacteria solution of Aquabacterium sp. SW9 and Chryseobacterium sp. MTW1 produced from water

Abstract

The present invention provides a process and its application of a tandem biological trickling filter tower with a combined bacterial solution of Alkaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, comprising the following steps: S1: Inoculate the fermented bacterial solutions of the two strains in series into the packing of the biological trickling filter tower. The packing of the biological trickling filter tower consists of two biological trickling filter towers in series. The first biological trickling filter tower is inoculated with Alkaligenes aquatilis SW9 for film formation, and the second biological trickling filter tower is inoculated with Chryseobacterium MTW1 for film formation. The film formation time is 24 hours; S2: Ensure that the total concentration of viable bacteria attached to the packing of the biological trickling filter tower is 1×10 8 CFU / mL, and the residence time of the malodorous gas in the biological trickling filter tower is 45 s. By combining highly efficient deodorizing strains with the biological trickling filter tower technology, the present invention purifies malodorous waste gas, can remove hydrogen sulfide, methanethiol and a composite gas of hydrogen sulfide and methanethiol at a relatively high concentration, and has the characteristics of high deodorization efficiency and high deodorization concentration compared with the existing deodorization technologies.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental microorganisms, and relates to a process and application of a biological trickling filter tower connected in series with a bacterial liquid of a water-producing alkaline bacterium SW9 and a Chryseobacterium MTW1. Background Art

[0002] With the continuous development of the economy and the advancement of urbanization, factories and municipal treatment facilities such as livestock farms, organic fertilizer processing plants, sewage treatment plants and landfills are increasing. The malodorous waste gas generated by these factories and facilities during the production and operation process has become one of the important factors that seriously affect people's daily life. The malodorous waste gas mainly includes sulfur-containing compounds such as hydrogen sulfide, methyl mercaptan and methyl sulfide, nitrogen-containing compounds such as ammonia, halogens and their derivatives, organic acids and oxygen-containing organic matter.

[0003] Malodorous waste gas has the characteristics of low content and low olfactory threshold. It not only pollutes the environment around the factory, but also harms people's health and affects the normal production and life. The treatment of malodorous waste gas is urgent. At present, the main methods for the treatment of malodorous gases at home and abroad are adsorption, chemical dosing, oxidation and incineration, but these traditional chemical and physical methods have problems such as high cost, complex equipment, high energy consumption and easy to cause secondary pollution. In contrast, biological deodorization methods such as biofilter method, biotrickling method and soil treatment method have attracted attention due to their advantages such as simple equipment, low operating costs and high efficiency, and have been widely used in the treatment of malodorous waste gas. Among them, the biotrickling method has attracted widespread attention due to its easy control of reaction conditions during operation, the filler is not easy to be blocked, the footprint is small, the deodorization efficiency is high, and it has a good removal effect on malodorous gases such as ammonia, hydrogen sulfide and methyl mercaptan.

[0004] Most of the current deodorization methods only target a single malodorous gas. There are few biological removal technologies for complex odors, and even fewer studies on the removal technology of typical sulfur-containing malodorous gases such as methyl mercaptan. These studies are often conducted when the methyl mercaptan content is low.

[0005] For example, the prior art CN202010035554.0 describes a combined process of biotrickling filtration + ultraviolet / catalytic oxidation, with removal rates of 91.40% and 53.10% for 30mg / m3 hydrogen sulfide and 10mg / m3 (about 5ppm) methyl mercaptan, respectively; the prior art CN201310206408.X describes a process of adding microbial active fillers of Ochrobacterium anthropogenum, with a removal rate of more than 90% for malodorous gases with a hydrogen sulfide concentration of 0.1-80mg / m3 and a methyl mercaptan concentration of 0.1-10mg / m3. At present, most of these published deodorization technologies deal with low concentrations of methyl mercaptan, and the treatment efficiency still needs to be improved. Summary of the Invention

[0006] The object of the present invention is to provide a process and its application of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, so as to solve the problems put forward in the above-mentioned background technology.

[0007] The object of the present invention can be achieved by the following technical solutions: A process of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, comprising the following steps:

[0008] S1: Inoculate the fermented bacterial solutions of the two strains in series into the packing of the biological trickling filter tower. The packing of the biological trickling filter tower consists of two biological trickling filter towers in series. The first biological trickling filter tower is inoculated with Alcaligenes aquatilis SW9 for film formation, and the second biological trickling filter tower is inoculated with Chryseobacterium MTW1 for film formation; the film formation time is 24 hours;

[0009] S2: Ensure that the total concentration of viable bacteria attached to the packing of the biological trickling filter tower is 1×10 8 CFU / mL, and the residence time of the malodorous gas in the biological trickling filter tower is 45 s.

[0010] In the above-mentioned process of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, in the fermentation broth, the total concentration of viable bacteria of strain SW9 is 1×10 9 CFU / mL, and the total concentration of viable bacteria of strain MTW1 is 1×10 9 CFU / mL.

[0011] In the above-mentioned process of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, the Alcaligenes aquatilis strain SW9 is classified and named as: Alcaligenes aquatilis, and the preservation number is CGMCC NO25252; a Chryseobacterium strain MTW1 is classified and named as: Chryseobacterium sp., and the preservation number is CGMCC NO25251.

[0012] In the above-mentioned application of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1, the application of the combined bacterial solution in a single malodorous gas containing hydrogen sulfide; the application in a single malodorous gas containing methanethiol, and the application in a composite gas containing hydrogen sulfide and methanethiol.

[0013] Compared with the prior art, the advantages of the process and its application of a tandem biological trickling filter tower with a combined bacterial solution of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 of the present invention are:

[0014] Strains capable of efficiently removing hydrogen sulfide and methanethiol were isolated and screened from different samples, namely Aquabacterium SW9 and Chryseobacterium MTW1. Both strains can grow in the environment of 10 - 30°C and pH 5 - 9, indicating that the two strains provided by the present invention have strong adaptability and can be widely applied to various waste gas treatments;

[0015] The two highly efficient deodorizing strains screened were respectively biofilm - formed on the packing of the biotrickling filter tower. Combining with the biotrickling filter tower technology, through pilot - scale tests, the removal rates of hydrogen sulfide with a concentration of 60 - 180 ppm, methanethiol with a concentration of 70 - 90 ppm, and the composite gas of methanethiol and hydrogen sulfide with a concentration of 100 - 180 ppm introduced into the process can all reach over 80%, showing high - efficiency removal effects on higher - concentration methanethiol and its composite gas;

[0016] It has a small floor area and low energy consumption. Moreover, the packing gaps in the biotrickling filter tower are moderate, which is conducive to the circulation of air and the absorption and decomposition of malodorous gases by the strain biofilms attached to the packing. It can enable the strains to grow well and is not likely to cause blockage of the packing, allowing the biotrickling filter tower system to play its role to a greater extent and having a high deodorization efficiency. Brief Description of the Drawings

[0017] Figure 1 Colony morphology of Aquabacterium SW9 and Chryseobacterium MTW1 provided by the present invention;

[0018] Figure 2 Growth curves of Aquabacterium SW9 and Chryseobacterium MTW1 provided by the present invention;

[0019] Figure 3 Optimal pH of Aquabacterium SW9 and Chryseobacterium MTW1 provided by the present invention;

[0020] Figure 4 Optimal temperature of Aquabacterium SW9 and Chryseobacterium MTW1 provided by the present invention;

[0021] Figure 5 Schematic diagram of the biotrickling device;

[0022] Figure 6 Removal rate of hydrogen sulfide single gas by strains SW9 and MTW1 combined with the biotrickling device;

[0023] Figure 7 Removal rate of methanethiol single gas by strains SW9 and MTW1 combined with the biotrickling device;

[0024] Figure 8 Removal rate of hydrogen sulfide - methanethiol composite gas by strains SW9 and MTW1 combined with the biotrickling device;

[0025] Figure 9 The viable cell count of the film-forming strain after treating gas with strain SW9 and strain MTW1. Specific embodiments

[0026] The following are specific embodiments of the present invention in combination with the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0027] A process for a tandem biological trickling filter tower with a combined bacterial liquid of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water and its application according to the present invention

[0028] The bacterial liquid of Alcaligenes aquatilis SW9 and the bacterial liquid of Chryseobacterium MTW1 are respectively coated on the packing of the biological trickling filter tower, and then the biological trickling filter towers filled with the packing attached with the strain biofilm are connected in series.

[0029] The process of the present invention has a purification effect on malodorous gases.

[0030] The process provided by the present invention contains the fermentation broth of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 of the present invention.

[0031] In the process of the present invention, the total viable cell concentration in the packing of the biological trickling filter tower is 1×10 7 -1 ×10 9 CFU / mL, preferably 1×10 8 CFU / mL.

[0032] The application of the process provided by the present invention to malodorous gases under pilot-scale tests, especially to malodorous gases containing methanethiol or / and hydrogen sulfide.

[0033] The application of the fermentation broth of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 in a biological trickling filter tower is also provided.

[0034] Furthermore, the application is to coat the fermentation broth of the fermented Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 on the packing filled in 2 biological trickling filter towers respectively to form a biofilm, and connect the 2 biological trickling filter towers in series (the first biological trickling filter tower is coated with SW9, and the second biological trickling filter tower is coated with MTW1).

[0035] Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 of the present invention are aerobic bacteria. Therefore, the biological trickling filter tower technology of the present invention needs to be carried out under aerobic conditions, and nutrient solution needs to be added regularly to maintain the normal growth and metabolism of the strains.

[0036] In the present invention, the method of immobilizing the fermentation broths of Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 on the packing can be carried out according to the conventional methods in the art. Alcaligenes aquatilis SW9 and Chryseobacterium MTW1 are respectively cultured by shaking for 48 h to obtain the fermentation broths. The fermentation broths of the two strains are respectively poured into the biotrickling filter tower to immerse the packing, and left standing for 24 h until the strains are immobilized on the packing to form a biofilm.

[0037] Example 1 Screening and Identification of High-Efficiency Odor-Decomposing Strains SW9 and MTW1

[0038] Luria-Bertani (LB) medium: Tryptone 10 g, Yeast extract 5 g, NaCl 10 g, Agar 12 g, made up to 1000 mL with distilled water, natural pH, sterilized at 121 °C for 20 min.

[0039] Sulfur-enriched medium: ammonium chloride (NH4Cl) 2.0 g, magnesium chloride (MgCl2) 0.5 g, dipotassium hydrogen phosphate (K2HPO4) 3.0 g, sodium sulfide nonahydrate (Na2S·9H2O) 10.0 g (filtered and sterilized, added after sterilization), calcium chloride (CaCl2·6H2O) 0.2 g, made up to 1000 mL with distilled water, pH = 6.1 ± 0.1, sterilized at 121 °C for 20 min.

[0040] Sulfide-degrading medium: sodium sulfide nonahydrate (Na2S·9H2O) 0.1 g, ammonium chloride (NH4Cl) 0.4 g, magnesium chloride (MgCl2) 0.2 g, dipotassium hydrogen phosphate (K2HPO4) 2.0 g, sodium carbonate (Na2CO3) 0.4 g, made up to 1000 mL with distilled water, pH = 6.1 ± 0.1, sterilized at 121 °C for 20 min.

[0041] Methyl mercaptan-containing medium: sodium chloride (NaCl) 2 g, ammonium chloride (NH4Cl) 1 g, dipotassium hydrogen phosphate (K2HPO4) 0.5 g, magnesium sulfate (MgSO4) 0.3 g, calcium chloride (CaCl2) 0.02 g, made up to 1000 mL with distilled water, methyl mercaptan added in proportion (added after filtration and sterilization), sterilized at 121 °C for 20 min.

[0042] Inorganic salt medium: dipotassium hydrogen phosphate (K2HPO4) 2 g, magnesium sulfate (MgSO4) 0.5 g, ferric sulfate (Fe2(SO4)3) 0.04 g, calcium chloride (CaCl2) 0.02 g, sodium chloride (NaCl) 2 g, made up to 1000 mL with distilled water, sterilized at 121 °C for 20 min.

[0043] 1. Isolation and Primary Screening of Hydrogen Sulfide Odor-Decomposing Bacteria

[0044] Weigh 10 g of each of the 3 soil samples taken from the vicinity of a chemical plant into 90 mL of sterilized deionized water in a 250 mL conical flask. At the same time, add 10 - 15 sterilized glass beads and shake and mix evenly for 2 - 4 h in a constant temperature shaker at 30 °C and 180 r / min to evenly disperse the bacteria in the deionized water. Transfer 5 mL of the bacterial suspension to a sulfur-enriched medium containing 100 mL, and culture it in a constant temperature shaker at 30 °C and 180 r / min. After observing uniform turbidity in the medium, transfer it again to a new sulfur-enriched medium at an inoculation amount of 5% and transfer it three times, and then separate the deodorizing strains by the dilution coating method. Take 1 mL of the transferred bacterial liquid into a sterilized 2 mL centrifuge tube, dilute it using a vortex shaker and sterile deionized water. Take 100 μL of the bacterial liquid and add it to a 2 mL sterile centrifuge tube containing 900 μL of sterile deionized water, that is, dilute it 10 times, and dilute it successively to a 10-6 gradient. Take 100 μL of the dilution solutions at three gradients of 10-4, 10-5, and 10-6 and evenly coat them on a sterilized glass Petri dish containing LB medium. Invert the Petri dish and culture it in a constant temperature incubator at 30 °C. After colonies grow on the Petri dish, pick single colonies with different colony morphological characteristics onto the LB medium and streak them in three zones for purification. After streaking at least three times, obtain the preliminarily purified deodorizing strains.

[0045] 2. Isolation and primary screening of methanethiol deodorizing bacteria

[0046] Weigh 10 g of each of the 3 soil samples taken from the vicinity of a chemical plant into a 250 mL conical flask containing 90 mL of sterilized deionized water. At the same time, add 10 - 15 sterilized glass beads and shake and mix evenly for 2 - 4 h in a constant temperature shaker at 30 °C and 180 r / min to evenly disperse the bacteria in the deionized water. Transfer 5 mL of the bacterial suspension to a methanethiol-containing medium with a methanethiol content of 200 mg / L, and culture it in a constant temperature shaker at 30 °C and 180 r / min. After observing uniform turbidity in the medium, transfer it to a methanethiol-containing medium with a methanethiol content of 500 mg / L at an inoculation amount of 5%, and transfer it successively to methanethiol-containing media with methanethiol contents of 800, 1000, and 1200 mg / L. After transferring five times, separate and purify the deodorizing strains by the dilution coating method.

[0047] 3. Screening of strains with high efficiency in removing hydrogen sulfide using methylene blue colorimetry

[0048] Pick and transfer the purified strain to LB liquid medium, and culture it in a constant temperature shaker at 30 °C and 180 r / min for 12 h to obtain a fresh seed solution for standby. Take the seed solution according to an inoculation amount of 5% and inoculate it into 100 mL of the sulfide-degrading medium, and culture it in a constant temperature shaker for 48 h. Then add a sodium sulfide solution to make the initial concentration of sulfide ions in the medium 500 mg / L. At the same time, use the medium without bacteria as a blank control. After adding the hydrogen sulfide solution, take 2 mL of the bacterial liquid every 3 h, centrifuge it at 12,000 r / min for 2 min, take 1 mL of the supernatant and put it into a 15 mL centrifuge tube, add carbon dioxide-free water to 8 mL, then add 1 mL of p-aminodimethylaniline solution, mix well, and then add 200 μL of ammonium ferric sulfate solution, mix well, and let it stand for 10 min. Take the mixed solution and use a glass colorimetric cell with an optical path of 10 mm at a wavelength of 665 nm, and use carbon dioxide-free water as a reference to measure the absorbance value. Calculate the content of sulfide ions in the solution through the standard curve, compare the test strain samples with CK, and calculate the removal rate of sulfide ions in the solution by each strain, so as to compare and re-screen the strains with high efficiency in removing hydrogen sulfide.

[0049] 4. Screening strains with high efficiency in removing methanethiol by gas chromatography

[0050] Pick and transfer the purified strain to LB liquid medium, and culture it in a constant temperature shaker at 30 °C and 180 r / min for 12 h to obtain a fresh seed solution for standby. Take the seed solution according to an inoculation amount of 5% and inoculate it into a glass bottle containing 50 mL of 1000 ppm methanethiol medium, and culture it in a constant temperature shaker for 72 h. At the same time, use the medium without bacteria as a blank control. After 72 h, take 2 mL of the medium, centrifuge it at 4 °C and 12,000 r / min for 2 min, take 0.1 - 1 mL of the supernatant and put it into a gas chromatography injection vial, use a gas chromatograph to measure the peak area, and calculate the corresponding methanethiol content through the methanethiol standard curve. Compare the test strain samples with CK, and calculate the removal rate of methanethiol in the solution by each strain, so as to re-screen the strains with high efficiency in removing methanethiol.

[0051] 5. Identification of deodorizing strains

[0052] 5.1 Extraction of total bacterial DNA

[0053] 1) Pick a single colony and inoculate it into 3 ml of LB liquid medium, and culture it in a constant temperature shaker at 28 °C and 180 rpm / min for 12 hours.

[0054] 2) Take 2 mL of each bacterial liquid, centrifuge it at 12,000 rpm / min for 2 min, and discard the supernatant.

[0055] 3) Resuspend the bacterial cells in 1 mL of sterile water, centrifuge it at 12,000 rpm / min for 2 min, and discard the supernatant. Wash it 3 times in this way.

[0056] 4) Add 270 μL of 1×TE buffer, pipette and mix well to fully resuspend the bacteria, then add 15 μL of lysozyme and incubate on ice for 30 min.

[0057] 5) Sequentially add 15 μL of 10% SDS and 10 μL of 100 μg / mL proteinase K, scrape and mix well, then place in a 37°C water bath for 30 min.

[0058] 6) Add 200 μL of 5 mol / L NaCl pre-cooled at 4°C, scrape and mix vigorously.

[0059] 7) Add 500 μL of phenol-chloroform for extraction, scrape and mix vigorously, then centrifuge at 12,000 rpm for 10 min.

[0060] 8) After centrifugation, the mixture separates into three layers. Transfer the topmost supernatant to a new 2 mL centrifuge tube, and repeat the extraction until there is no white flocculent precipitate at the interface.

[0061] 9) Transfer the obtained supernatant to a 1.5 mL EP tube, add 0.8 times the volume of 1×TE buffer (about 400 μL), then add 1 times the volume of isopropanol (about 500 μL), invert and mix well, then place in a -70°C ultra-low temperature freezer for 10 - 15 min.

[0062] 10) Take out the sample, centrifuge at 12,000 rpm for 10 min, discard the upper supernatant, and wash the precipitate 3 times with 70% ethanol pre-cooled at 4°C.

[0063] 11) After natural air drying, add 30 μL of sterilized ddH₂O to dissolve, and store at 4°C for later use.

[0064] 5.2 16S rRNA gene amplification

[0065] Perform PCR amplification using 16S rRNA universal primers. The reaction system is shown in Table 2, and the primer sequences are shown in Table 1:

[0066] Table 1 16S rRNA universal primer sequences

[0067]

[0068] Table 2 PCR reaction system (system volume is 50 μL)

[0069]

[0070] PCR reaction conditions: pre-denaturation at 95°C for 5 min; denaturation at 94°C for 30 s, annealing at 55°C for 30 s, extension at 72°C for 1.5 min (30 cycles); terminal extension at 72°C for 10 min. The PCR product is about 1,500 bp. Take 3 μL of the PCR product for agarose gel electrophoresis detection. If the band is bright and clear, sequence the PCR product, which is completed by Nanjing Qingke Biotechnology Co., Ltd. The obtained sequence is submitted to the NCBI nucleic acid database (http: / / blast.ncbi.nlm.nih.gov) for sequence alignment.

[0071] After identification, strain SW9 is Alcaligenes aquatilis and strain MTW1 is Chryseobacterium sp. They were isolated from a landfill in Nanjing in November 2020 and deposited in the General Microbiological Center of the China Committee for Culture Collection of Microorganisms on July 8, 2022. The deposit number of strain SW9 is CGMCC: 25252, and the deposit number of strain MTW1 is CGMCC: 25251. They are respectively classified and named as Alcaligenes aquatilis and Chryseobacterium sp. The address is: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing 100101.

[0072] Example 2 Growth curves of strain SW9 and strain MTW1

[0073] Pick Figure 1 The single colony shown in the figure into LB liquid medium and shake culture at 37°C for 12 hours to obtain a fresh seed solution. Take 9 50-ml Erlenmeyer flasks containing 20 ml of liquid LB medium, labeled 01, 02, 03, SW9-1, SW9-2, SW9-3, MTW1-1, MTW1-2, MTW1-3. SW9-1, SW9-2, SW9-3, MTW1-1, MTW1-2, MTW1-3 are experimental groups. The experimental groups are inoculated with 100 μL of the seed solution into the Erlenmeyer flasks at an inoculation amount of 1%. The blank group is added with the same volume of sterile water, and one group is used as three replicates. Starting from 0 hour, measure the absorbance value A at 600 nm with a spectrophotometer every hour. Use the blank group as the blank control. Obtain the growth curves of strain SW9 and strain MTW1 in LB for 48 hours. As Figure 2 shown, the optimal value has been reached at 24 hours.

[0074] Example 3 Determination of the optimal pH and optimal temperature of strain SW9 and strain MTW1

[0075] Pick Figure 1The single colony shown was cultured in LB liquid medium at 37°C with shaking for 12 hours to obtain a fresh seed solution. 66 test tubes containing 5 ml of liquid LB medium were taken, and their pH was adjusted with a pH meter. Every three test tubes were used as a replicate for a certain pH value, and the pH range was 3 - 13. The medium at normal pH was used as a control. In the experimental groups, 100 μL of the seed solution was inoculated into Erlenmeyer flasks at an inoculation amount of 1%. The blank group was added with the same volume of sterile water. After 12 hours, the number of bacteria of strain SW9 and strain MTW1 was measured, and the blank group was used as a blank control. The optimal pH values of strain SW9 and strain MTW1 between pH = 3 - 13 were obtained. As Figure 3 shown. The optimal pH of strain SW9 was between 5 - 12, and the optimal pH of strain MTW1 was between 5 - 10.

[0076] Pick Figure 1 the single colony shown in LB liquid medium and culture it at 28°C for 12 hours to obtain a fresh seed solution. 30 test tubes containing 5 ml of liquid LB medium were taken, with every three tubes as a group for replication, a total of 5 groups. They were respectively placed in shakers at 10°C, 20°C, 30°C, 40°C, and 50°C for shaking culture. After 12 hours, the number of bacteria was measured, and the blank group was used as a blank control. The optimal temperatures of strain SW9 and strain MTW1 were obtained. As Figure 4 shown. The optimal temperature of strain MTW1 was between 20°C - 40°C, and the optimal pH temperature of strain MTW1 was between 20°C - 30°C.

[0077] Example 4 Film - forming process of strain SW9 and strain MTW1 combined with the packing of a biotrickling filter tower

[0078] Pick the single colony of the deodorizing strain from the plate and transfer it to LB liquid medium. Culture it in a constant - temperature shaker at 30°C and 180 r / min for 12 h to obtain a fresh seed solution for standby. Take the fresh seed solution of the strain at an inoculation amount of 5% and place it in 100 mL of sterilized LB liquid medium, and culture it in a constant - temperature shaker for 12 h. Transfer 100 mL of the cultured bacterial liquid to 500 mL of sterilized LB medium at an inoculation amount of 2% and culture it in a constant - temperature shaker for another 24 h. Finally, load 1.5 L of sterilized ceramsite packing into the biotrickling filter tower, pour the above - cultured bacterial liquid into the filter tower to immerse the packing, and let it stand for 24 h. After 24 h, drain the bacterial liquid, observe the appearance of a biofilm on the surface of the filter material, and wait for aeration operation.

[0079] Example 5 Removal rate of hydrogen sulfide single gas by strain SW9 and strain MTW1 combined with biotrickling filter tower technology

[0080] Use a small - scale biotrickling filter tower device at the pilot - scale to simulate the actual factory environment (such as Figure 5As shown in the figure, by inoculating strain SW9 in biotrickling filter tower 1, strain MTW1 in biotrickling filter tower 2, and connecting the two biotrickling filter towers in series, a single hydrogen sulfide gas with a concentration of 60 - 180 ppm was removed. The concentration of hydrogen sulfide gas was detected using the RAE MiniRAE Lite portable VOC detector from the United States. The hydrogen sulfide gas concentrations at the inlets and outlets of biotrickling filter tower 1 and biotrickling filter tower 2 were measured respectively. By comparing the concentration changes of the gas between the outlet and the inlet, the removal rates of hydrogen sulfide by strain SW9 and strain MTW1 under the pilot test and the removal rate of the single hydrogen sulfide gas by the biotrickling filter system could be calculated. The test lasted for 5 days. The results are as Figure 6 shown:

[0081] (1) Within 5 days, the maximum removal rate of the single hydrogen sulfide gas with a concentration of 60 - 180 ppm by the tandem biotrickling filter tower system of strain SW9 and strain MTW1 could reach 84.27%. The removal rate was between 58.35% and 84.27%, with a relatively high removal rate. The removal rate of hydrogen sulfide by strain SW9 was higher than that of strain MTW1. For the removal of hydrogen sulfide gas, strain SW9 was dominant.

[0082] Example 6 Removal Rate of Methyl Mercaptan Single Gas by the Combination of Strain SW9 and Strain MTW1 with Biotrickling Filter Tower Technology

[0083] Using a small - scale pilot - scale biotrickling filter tower device to simulate the actual factory environment (as Figure 5 shown), strain SW9 was inoculated in biotrickling filter tower 1, strain MTW1 was inoculated in biotrickling filter tower 2, and the two biotrickling filter towers were connected in series. A single methyl mercaptan gas with a concentration of 70 - 90 ppm was introduced from the bottom of biotrickling filter tower 1, and the two strains inoculated in the biotrickling filter tower were used to decompose and remove the methyl mercaptan malodorous gas.

[0084] The concentration of methyl mercaptan gas was detected using the RAE MiniRAE Lite portable VOC detector from the United States. The methyl mercaptan gas concentrations at the inlets and outlets of biotrickling filter tower 1 and biotrickling filter tower 2 were measured respectively. By comparing the concentration changes of the gas between the outlet and the inlet, the removal rates of methyl mercaptan by strain SW9 and strain MTW1 under the pilot test and the removal rate of the single methyl mercaptan gas by the biotrickling filter system could be calculated. The test lasted for 5 days. The results are as Figure 7 shown:

[0085] (1) For a single methyl mercaptan gas with a concentration of 70 - 90 ppm, the removal rate of the tandem biotrickling filter tower system of strain SW9 and strain MTW1 was 60.31% - 100%. It reached the maximum value on the 5th day. The concentration of methyl mercaptan at the outlet was lower than the detection value, and the removal rate reached 100%, with a high removal efficiency. For the single methyl mercaptan gas, the removal rate of strain MTW1 was higher than that of strain SW9.

[0086] Example 5 Removal of a composite gas of methanethiol and hydrogen sulfide by using strain SW9 and strain MTW1 in combination with a biotrickling filter technology

[0087] A pilot-scale small biotrickling filter device was used to simulate the actual factory environment (as Figure 5 shown). Strain SW9 was used to form a biofilm on the packing of biotrickling filter 1, and strain MTW1 was used to form a biofilm on the packing of biotrickling filter 2. The two biotrickling filters were connected in series. A composite gas of methanethiol and hydrogen sulfide with a concentration of 100 - 180 ppm and air were introduced from the bottom of biotrickling filter 1, and the two strains of biofilms attached to the packing of the biotrickling filter were used to decompose and remove the methanethiol and hydrogen sulfide malodorous gases.

[0088] The concentration of the composite gas of methanethiol and hydrogen sulfide was detected by a MiniRAELite portable VOC detector. The concentrations of the composite gas at the inlet and outlet of biotrickling filter 1 and biotrickling filter 2 were measured respectively, and the concentration changes of the gas between the outlet and the inlet were compared, so as to calculate the removal rates of the composite gas by strain SW9 and MTW1 under the pilot test respectively and the removal rate of the composite gas of methanethiol and hydrogen sulfide by the whole biotrickling system. The test lasted for 5 days. The results are as Figure 8 shown: In the 5-day test, the removal rate of the composite gas of methanethiol and hydrogen sulfide with a concentration of 100 - 180 ppm by the series biotrickling filter system of strain SW9 and strain MTW1 was in the range of 66.03% - 92.64%, reaching the maximum value on the 4th day and then decreasing to 88.72%, with a high removal efficiency.

[0089] Example 6 Detection of the microbial content on the packing after the operation of the biotrickling filter process

[0090] 10 g of the packing in the biotrickling filter system after operation was taken and added to 90 mL of sterile deionized water, and an appropriate amount of sterilized glass beads were added. The mixture was shaken on a constant temperature shaker at 30 °C and 180 r / min for 2 - 4 h to free the microorganisms attached to the packing into the sterile deionized water. The above bacterial solution was diluted to 10-7 in sequence, and the bacterial solutions with dilution gradients of 10-5, 10-6, and 10-7 were spread on an LB medium. The culture dishes were inverted and placed in a constant temperature incubator for static culture until colonies grew, and the colonies on the plates were counted. Figure 9 The number of viable bacteria attached to the packing is shown. After the 5-day malodorous gas test, the number of viable bacteria on the packing can still reach more than 1×108, indicating that both strains can tolerate a high concentration of hydrogen sulfide and methanethiol and can survive stably in the biotrickling filter.

[0091] The content not detailedly described in this specification belongs to the prior art well-known to those skilled in the art. The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains may make various modifications or supplements to the described specific embodiments or use similar means for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A process of a tandem biological trickling filter tower with a combined bacterial liquid of Alcaligenes aquatilis SW9 and Chryseobacterium sp. MTW1 for producing alkali from water, characterized in that, It includes the following steps: S1: Inoculate the fermented bacterial solutions of two strains in series in the packing of the biotrickling filter tower. The packing of the biotrickling filter tower consists of two biotrickling filter towers connected in series. The first biotrickling filter tower is inoculated with the film-forming inoculation water of Alcaligenes aquatilis SW9, and the second biotrickling filter tower is inoculated with the film-forming Chryseobacterium MTW1. The film-forming time is 24 hours; S2: Ensure that the total concentration of viable bacteria attached to the packing in the biotrickling filter tower is 1×10 8 CFU / mL, and the residence time of the malodorous gas in the biotrickling filter tower is 45 s; The Alcaligenes aquatilis strain SW9 is classified and named as Alcaligenes aquatilis, and its preservation number is CGMCC NO25252; a Chryseobacterium strain MTW1 is classified and named as Chryseobacterium sp., and its preservation number is CGMCC NO25251.

2. The process of the combined bacterial liquid series biological trickling filter tower according to claim 1, characterized in that In the fermentation broth, the total viable concentration of strain SW9 is 1×10 9 CFU / mL, and the total viable concentration of strain MTW1 is 1×10 9 CFU / mL.

3. Application of the combined bacterial liquid series biological trickling filter tower process according to claim 1, characterized in that, The application of the combined bacterial solution in a single malodorous gas containing hydrogen sulfide, or in a single malodorous gas containing methanethiol, or in a composite gas containing hydrogen sulfide and methanethiol.

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