Method for strengthening rapid biofilm formation of efficient volatile organic compound degrading bacteria in biological device

Abstract

The invention discloses a method for intensifying rapid biofilm formation of high-efficiency volatile organic compound degrading bacteria in a biological device, which adopts a laminated intensifying biofilm formation mode and specifically comprises the following steps: firstly, attaching a signal molecule I solution on the surface of a filler and in internal pores of the biological device in a spraying or dipping mode; spraying and uniformly distributing high-efficiency volatile organic compound degrading bacteria and circulating liquid containing an inorganic salt nutrient solution and a composite trace ion enhancer into the biological device filler, intermittently spraying and uniformly distributing a signal molecule II solution into the biological device, and secondarily uniformly distributing the degrading bacteria and the circulating liquid into the biological filler. Wherein the signal molecule I and the signal molecule II regulate and control the formation of extracellular polymeric substances and accelerate the adhesion and colonization of the efficient volatile organic compound degrading bacterial agent on the biological filler, the compound ion enhancer promotes the growth of microorganisms and the pollutant degradation capability, and the signal molecule I and the signal molecule II synergistically promote the rapid biofilm formation of the bioreactor; and the film hanging starting time of the device is effectively shortened, and the engineering operation effect and stability are improved.

Description

Technical field:

[0001] The invention relates to the technical field of volatile organic matter treatment, and in particular to a method for strengthening the rapid biofilm formation of high-efficiency volatile organic matter degrading bacteria in a biological device. Background technology:

[0002] Volatile organic compounds (VOCs) emissions can cause PM2.5, O 3 VOCs emission reduction is the main task of air pollution prevention and control in my country. Bio-trickling / filtration has become one of the main methods for treating medium and low concentration VOCs due to its economical, effective and environmentally friendly characteristics.

[0003] Microorganisms are the core of biotrickling / filtration technology. Free microorganisms colonize on the surface of the filler by self-adhesion and secretion of extracellular polymers. Then, the microorganisms continue to divide and proliferate to form colony aggregates, and finally form a mature biofilm with a three-dimensional structure. After VOCs pollutants reach the surface of the biofilm through gas-liquid mass transfer, they are captured and absorbed by the surface microorganisms of the biofilm, and then degraded through the metabolic transformation of the microbial specialized degradation flora. The biofilm can provide support and protection for the growth and metabolism of the flora in the membrane. Therefore, the structural characteristics of the biofilm in the reactor of the biotrickling / filtration device and the diversity and stability of its microbial population structure are the key to the efficient degradation of VOCs and stable operation of the system.

[0004] The reactor of the biological trickling filter / filtration device needs to be started by inoculating bacteria to form biofilm. Traditional biofilm formation methods mostly use the original activated sludge from the sewage treatment plant for inoculation. Although the activated sludge contains a large number of microorganisms, the bacterial community structure is unstable and does not have the "target" characteristics. The activated sludge may not contain or contain little effective microorganisms that have the ability to efficiently degrade the VOCs waste gas components to be treated. As a result, the activated sludge inoculated in the reactor is slow to domesticate and proliferate, the biofilm formation cycle is long, and the removal effect is unstable, which makes the device have the disadvantages of long startup time, low removal efficiency during the startup period, and poor stability of the engineering operation effect. Summary of the invention:

[0005] The purpose of the present invention is to provide a method for strengthening the rapid biofilm formation of high-efficiency volatile organic compound (VOCs) degrading bacteria in a biological device, shorten the biofilm formation start-up time of volatile organic compound (VOCs) degrading bacteria in the biological device, improve the stability of engineering operation, and solve the problems of long device startup time, low removal efficiency during the startup period, and poor stability of engineering operation effect in the biofilm formation start-up process of treating VOCs by biological trickling filtration / filtration in the prior art.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for strengthening the rapid biofilm formation of efficient volatile organic compound degrading bacteria in a biological device, the method comprising the following steps: configuring a signal molecule I with an aqueous solution having a concentration of 1 to 5 μg / L, and attaching it to the surface of the biological device filler and the internal pores by spraying or dipping, then uniformly distributing the efficient volatile organic compound (VOCs) degrading bacteria in the biological device filler, introducing volatile organic compound (VOCs) gas into the biological device, and cyclically spraying a circulating liquid containing an inorganic salt nutrient solution and a composite trace ion enhancer by dripping, spraying for 24 hours, configuring a signal molecule II with a solution having a concentration of 500 to 1000 μmol / L, and using intermittent filtration. The signal molecule I is N-acyl homoserine lactone (AHLs), selected from one of C10-HSL, C12-HSL, oxo-C6-HSL, oxo-C8-HSL, and oxo-C14-HSL; the signal molecule II is furanone acyl boric acid diester; the inorganic salt nutrient solution includes 3.0-4.5 g / L Na 2 HPO 4 12H 2 O, 0.7~1g / LKH 2 PO 4 1.5~2.5g / LNH 4 Cl, 0.015~0.023g / L CaCl 2 ·2H 2 O and 0.1-0.2 g / L MgCl 2 7H 2 O.

[0008] The solution dosage of signal molecule I is 1-2 L / m 3 Filler. The spraying amount of signal molecule II solution is 1-2L / m 3 Filler. The spraying rate of inorganic salt nutrient solution is 10-15L / min.

[0009] Furthermore, the method of evenly distributing the high-efficiency volatile organic compound (VOCs) degrading bacteria in the biological device filler is to use an intermittent spraying mode to spray the high-efficiency volatile organic compound (VOCs) degrading bacteria evenly in the biological device filler through the biological device spraying system, and the high-efficiency volatile organic compound (VOCs) degrading bacteria are sprayed 3 to 5 times, and each spraying is stopped for 10 minutes, and the cycle is repeated until the high-efficiency volatile organic compound (VOCs) degrading bacteria are all sprayed and evenly distributed in the biological filler. The addition ratio of the high-efficiency volatile organic compound (VOCs) degrading bacteria is 1 to 2 L / m 3 filler.

[0010] The composite trace ion enhancer includes a total ion concentration of 4 to 10 mg / L Fe 3+ 、Zn 2+ Mg 2+ At least two of the above are selected from two or more of ferric chloride, ferric sulfate, zinc chloride, zinc sulfate and magnesium chloride.

[0011] Volatile organic compounds (VOCs) gas is introduced into the biological device, and the VOCs intake load is 50% to 100% of the designed intake load.

[0012] The volatile organic compounds include benzene series, methyl mercaptan, and esters, and are preferably selected from at least one of ethylbenzene, xylene, ethyl acetate, toluene, and methyl mercaptan.

[0013] The biofilm formation conditions are: temperature 20-35°C, device residence time>15s, and circulating liquid pH value 6-8.

[0014] Furthermore, the successful biofilm formation of the biofilm device is marked by a VOCs removal rate of more than 70% or a unit filler removal load of more than 2500 mg / (m 3 h).

[0015] The highly efficient volatile organic compound (VOCs) degrading bacteria adopts the method of domestication and expansion culture outside the device, which saves the time of domestication and proliferation of bacteria in engineering applications. It is obtained by the following method:

[0016] (1) The filler in the existing biofiltration device is immersed in water, and the filler is intermittently ultrasonically pretreated in batches using an ultrasonic water bath oscillator to peel off the biofilm. Then, the filler and impurities are filtered using a 20-mesh screen to separate the biofilm suspension for later use. An equal volume of inorganic salt nutrient solution is added to the biofilm suspension, and the bacterial suspension A is obtained after culturing under air immersion for 24 hours;

[0017] (2) The bacterial suspension A is uniformly mixed with aerobic activated sludge from a sewage treatment plant in a chemical park in a volume ratio of (1-2):1 to obtain a bacterial suspension B, which is used as a bacterial source for a VOC-degrading bacterial agent;

[0018] (3) The bacterial suspension B is tamed as follows: first, the bacterial suspension B and the inorganic salt nutrient solution are added to the bacterial fermentation tank, and the volume ratio of the bacterial suspension B to the inorganic salt nutrient solution is 1:(3-5). The liquid level at this time is recorded as the initial liquid level; aeration is started for 34 hours, and the mixture is allowed to settle for 2 hours. 1 / 2-1 / 3 of the supernatant is discharged, and 1 / 2-1 / 3 of the inorganic salt nutrient solution is added to the initial liquid level. Two cycles are run, and then the aeration time is shortened to 23 hours, and the mixture is allowed to settle for 1 hour. Two cycles are run, and after the last cycle of settling, the bacterial suspension C is obtained.

[0019] (4) The bacterial suspension C is expanded and cultured as follows: the bacterial suspension C is added with an inorganic salt nutrient solution at a volume ratio of 1:9, aeration is started, and expanded culture is performed for 36 to 48 hours to obtain highly efficient volatile organic compound (VOCs) degrading bacteria.

[0020] The existing biological filtration device described in step (1) is a small-scale, pilot or engineering biological filtration device with similar intake VOCs components, and its intake load is 80% to 150% of the designed intake load value of the biological device of this application, its VOCs removal rate is more than 60%, and the operating time should be greater than 1 year to ensure the maturity of its biofilm and the stability of its bacterial community structure.

[0021] The intermittent ultrasonic pretreatment in step (1) is carried out in batches, each batch of filler is not more than 5L, each batch of ultrasound has a total of 10 cycles, each cycle includes ultrasound for 20 to 50 seconds, and standing for 10 to 40 seconds. The total time of ultrasound and standing time in each cycle is 60 seconds, the ultrasonic power is 1000W / 40%, the temperature is 20°C, and the oscillation speed is 120r / min.

[0022] The strain fermentation tank has the functions of replenishing liquid, discharging supernatant, discharging sludge and aeration. During the acclimation period, the VOCs target pollutants are introduced into the air with a gradient concentration. The first air intake load shall not be lower than the minimum design air intake load of the subsequent biological device, and the final air intake load shall not be lower than the maximum design air intake load of the subsequent biological device. During the expansion culture period, the VOCs target pollutant intake load shall not be lower than the maximum design air intake load of the subsequent biological device.

[0023] The beneficial effects of the present invention are:

[0024] 1) The present invention adopts a stacking enhanced biofilm formation method. First, the signal molecule I impregnated with the filler is an N-acyl homoserine lactone (AHLs) signal molecule, which is a quorum sensing signal molecule of most Gram-negative bacteria. The signal molecule I is impregnated to adhere to the surface and internal pores of part of the inorganic filler, which is beneficial to enhancing the colonization of VOCs degrading bacteria on the filler and facilitating the formation of a monolayer biofilm of the bacterial agent. The signal molecule II furanone acyl boric acid diester used in the secondary spraying is an AI-2 type quorum sensing signal molecule for interspecies communication, which can promote communication between bacteria, promote the colonization, growth and enrichment of different species of microorganisms in VOCs degrading bacteria, promote the dynamic development of the population, and is beneficial to constructing a complementary multi-niche and multifunctional co-metabolism microbial flora, thereby enhancing the degradation of pollutants in the biological device.

[0025] 2) The present invention adds a composite trace ion enhancer, wherein the metal cation Fe 3+ 、Zn 2+ Through the ion bridging effect, a three-dimensional matrix is ​​formed on the surface of the bacteria, which promotes microbial adsorption and colony aggregation, and is also beneficial to the capture of pollutants by microorganisms, and promotes the mass transfer and degradation of VOCs between membranes.2+ It interacts with the active groups in the extracellular polymers and increases the protein / polysaccharide ratio of the extracellular polymers by promoting protein secretion, thereby enhancing the mass transfer capacity and biodegradation capacity of the VOCs-degrading bacteria for hydrophobic VOCs. Compared with single ions, the interaction between complex trace ions can promote the growth and proliferation of VOCs-degrading bacteria faster, enhance the metabolic capacity of strains, and contribute to the aggregation of VOCs-degrading bacteria, the increase of extracellular polymers, and the formation and maturation of biofilms.

[0026] In summary, the present invention uses signal molecules I and signal molecules II to regulate the formation of extracellular polymers, accelerates the adhesion and colonization of VOC-degrading bacterial agents on biological fillers, and uses composite ion enhancers to promote the growth and metabolism of microorganisms and enhance the ability of microorganisms to degrade pollutants. The two synergistically promote the rapid biofilm formation of the bioreactor, effectively shorten the biofilm formation start-up time of the device, increase the removal rate of pollutants, and improve the engineering operation effect and stability. Description of the drawings:

[0027] Figure 1 This is a schematic diagram of the fast film-forming method of the present invention;

[0028] Among them, (1) is the period of rapid biofilm formation of single-layer bacteria, and the gray hexagon indicates signal molecule I; (2) is the completion of rapid biofilm formation of single-layer bacteria, forming the first layer of biofilm; (3) is the period of rapid biofilm formation of multi-layer bacteria, and the gray 3 / 4 circle indicates signal molecule II; (4) is the completion of rapid biofilm formation, forming a mature biofilm.

[0029] Figure 2 is a schematic diagram of the biological device of the present invention;

[0030] Among them, 1. circulating water tank; 2. circulating spray system; 3. biological filler; 4. biological trickling filter / filtration reactor; 5. centrifugal fan.

[0031] Figure 3 It is a comparison diagram of the methyl mercaptan effects of the experimental group and the blank control group in Example 1.

[0032] Figure 4 This is a comparison chart of toluene removal effects between the experimental group and the blank control group in Example 2. Specific implementation method:

[0033] The following is a further description of the present invention, rather than a limitation of the present invention.

[0034] Example 1: A method for enhancing the rapid biofilm formation of efficient methyl mercaptan-degrading bacteria in a biological device

[0035] (1) Take an appropriate amount of an existing biofiltration pilot plant (the methyl mercaptan inlet load of the plant is 4500 mg / (m 3h), the residence time is 10-20s, and the average removal rate of methyl mercaptan is 95%. It has been running stably for 1 year, its biofilm is mature, and the flora structure is stable) The filler in the water is immersed, and the filler is subjected to intermittent ultrasonic pretreatment in batches by ultrasonic water bath oscillator to peel off the biofilm. Each batch of fillers is 5L, and each batch of ultrasound has a total of 10 cycles, each cycle includes ultrasound 20s, standing 40s, and each cycle ultrasound and standing time total time is 60s, ultrasonic power 1000W / 40%, temperature 20°C, and oscillation speed 120r / min. Then, a 20-mesh screen is used to filter the filler and impurities, and the biofilm suspension is separated for standby use. An equal volume of inorganic salt nutrient solution is added to the biofilm suspension, and after 24h of suffocation and cultivation, a bacterial suspension A is obtained.

[0036] (2) The bacterial suspension A was evenly mixed with the aerobic activated sludge from the chemical park sewage treatment plant at a ratio of 2:1 (V / V) to obtain the bacterial suspension B, which was used as the bacterial source of the VOC-degrading bacterial agent.

[0037] (3) The bacterial suspension B was domesticated as follows: First, the bacterial suspension B and the inorganic salt nutrient solution were added to the bacterial fermentation tank. The volume ratio of bacterial suspension B to inorganic salt nutrient solution was 1:3. The liquid level at this time was recorded as the initial liquid level. Aeration was started for 34 hours, and the solution was allowed to settle for 2 hours. 1 / 2 to 1 / 3 of the supernatant was drained, and 1 / 2 to 1 / 3 of the inorganic salt nutrient solution was added to the initial liquid level. Two cycles were run. Then, the aeration time was shortened to 23 hours, and the solution was allowed to settle for 1 hour. Two cycles were run. The bacterial suspension C was obtained after the last cycle of settling. During the domestication period, the VOCs target pollutants were sulfur-containing organic matter, and the gradient air intake load was 500, 1000, 2000, and 3000 mg / (m 3 h) Air intake, residence time is 20s.

[0038] (4) The bacterial suspension C was expanded and cultured as follows: the bacterial suspension C was added with inorganic salt nutrient solution at a volume ratio of 1:9, aeration was started, and expanded culture was carried out for 36 to 48 hours to obtain VOC-degrading bacteria. During the expanded culture period, the VOCs target pollutant intake load was 3000 mg / (m 3 h), the dwell time is 20s.

[0039] (5) The signal molecule I (oxo-C6-HSL) was dissolved in water at a concentration of 5 μg / L and impregnated into the filler for 12 h, so that it adhered to the surface of the filler and the internal pores.

[0040] (6) The VOC degrading bacteria obtained in step (4) are sprayed at 2 L / m through the circulating water tank spray system (2). 3The filler ratio is evenly distributed in the biological filler (3) by using an intermittent spraying mode. The intermittent spraying mode is that the VOCs degrading bacteria are sprayed three times, and a 10-minute pause is made after each spraying, and the cycle is repeated until all the VOCs degrading bacteria are sprayed evenly in the biological filler.

[0041] (7) Biological device (4) starts to feed methyl mercaptan gas. The average concentration of methyl mercaptan in the gas is 20 mg / m 3 , residence time 15s.

[0042] (8) The circulating water tank (1) is 2L / m 3 Filler volume ratio: add inorganic salt nutrient solution, 2mg / L Mg 2+ and 2mg / LFe 3+ The composite trace ion enhancer is dissolved and mixed evenly, and then sprayed in a drip filtration cycle for 24 hours.

[0043] (9) Dissolve the signal molecule II (furanone acyl boric acid diester) in water to a final concentration of 1000 μmol / L. The solution spraying amount is 2 L / m 3 Filler. The signal molecule is evenly distributed in the biological device (4) by intermittent spraying. The signal molecule II is sprayed three times, and a 5-minute pause is made after each spraying, and the cycle is repeated until all the signal molecules II are sprayed and evenly distributed in the biological device (4).

[0044] (10) VOC degrading bacteria are sprayed at a rate of 1 L / m through the circulating water tank spray system (2). 3 The filler ratio is evenly distributed in the biological filler (3) twice by using an intermittent spraying mode.

[0045] (11) Add inorganic salt nutrient solution, 2mg / LMg into the circulating water tank (1) 2+ and 2mg / LFe 3+ The composite trace ion enhancer is dissolved and mixed evenly, and then circulated and sprayed in a drip filtration manner for 48 hours.

[0046] Among them, the inorganic salt nutrient solution composition is 4.5g / LNa 2 HPO 4 12H 2 O, 1g / LKH 2 PO 4 、2.5g / LNH 4 Cl, 0.023 g / L CaCl 2 ·2H 2 O and 0.2 g / LMgCl 2 7H 2 O, the spraying rate of inorganic salt nutrient solution is 10L / min. The biofilm formation environmental conditions of the biological device are: temperature 20-35℃, device residence time>15s, and circulating liquid pH value 6-8.

[0047] Blank control group:

[0048] Reference Example 1, except that signal molecule I (oxo-C6-HSL) and signal molecule II (furanone acyl boric acid diester) were not added, and 2 mg / LMg 2+ and 2mg / LFe 3+ A complex trace ion enhancer.

[0049] Control group 1:

[0050] Refer to Example 1, except that signal molecule I (oxo-C6-HSL) and signal molecule II (furanone acyl boric acid diester) were not added.

[0051] Control group 2:

[0052] Reference Example 1, except that 2 mg / L Mg was not added 2+ and 2mg / LFe 3+ A complex trace ion enhancer.

[0053] The results of the comparative test show that (please refer to Figure 3 ), the experimental group successfully formed biofilm on the 8th day by the method of Example 1, and the average removal rate of methyl mercaptan during stable operation was 92.21%. The blank control group successfully formed biofilm on the 22nd day by the method of the blank control group, and the average removal rate of methyl mercaptan during stable operation was 71.81%. The control group 1 successfully formed biofilm on the 18th day by the method of the control group 1, and the average removal rate of methyl mercaptan during stable operation was 81.48%. The control group 2 successfully formed biofilm on the 14th day by the method of the control group, and the average removal rate of methyl mercaptan during stable operation was 79.58%. By comparing Example 1, the blank control group, and the control group 1-2, it can be seen that the addition of signal molecule Ⅰ (oxo-C6-HSL) and signal molecule Ⅱ (furanone acyl boric acid diester) and 2mg / LMg 2+ and 2mg / LFe 3+ The composite trace ion enhancer works synergistically to significantly increase the removal rate of the pollutant methyl mercaptan, while also effectively shortening the biofilm startup time of the device.

[0054] Example 2: A method for enhancing the rapid biofilm formation of efficient toluene-degrading bacteria in a biological device.

[0055] (1) Take an appropriate amount of existing petrochemical industry engineering biofiltration device (the air intake load of the device is 4500mg / (m 3h), the residence time is 20s, and the average VOCs removal rate is 95%. It has been running stably for 2 years, its biofilm is mature, and the bacterial structure is stable) The filler in the water is immersed, and the filler is intermittently ultrasonically pretreated in batches using an ultrasonic water bath oscillator to peel off the biofilm, and intermittent ultrasonic pretreatment is performed in batches. Each batch of filler is 4L, and each batch of ultrasound has a total of 10 cycles, each cycle includes ultrasound for 50s, standing for 10s, and the total time of ultrasound and standing for each cycle is 60s, the ultrasonic power is 1000W / 40%, the temperature is 20℃, and the oscillation speed is 120r / min. Then, a 20-mesh screen is used to filter the filler and impurities, and the biofilm suspension is separated for use. An equal volume of inorganic salt nutrient solution is added to the biofilm suspension, and after 24h of suffocation and cultivation, bacterial suspension A is obtained.

[0056] (2) The bacterial suspension A was evenly mixed with the aerobic activated sludge from the petrochemical park sewage treatment plant in a ratio of 2:1 (V / V) to obtain the bacterial suspension B, which was used as the bacterial source of the VOC-degrading bacterial agent.

[0057] (3) The bacterial suspension B was domesticated as follows: First, the bacterial suspension B and the inorganic salt nutrient solution were added to the bacterial fermentation tank, and the volume ratio of the bacterial suspension B to the inorganic salt nutrient solution was 1:5. The liquid level at this time was recorded as the initial liquid level. Aeration was started for 34 hours, and the solution was allowed to settle for 2 hours. 1 / 2 to 1 / 3 of the supernatant was drained, and 1 / 2 to 1 / 3 of the inorganic salt nutrient solution was added to the initial liquid level. Two cycles were run. Then, the aeration time was shortened to 23 hours, and the solution was allowed to settle for 1 hour. Two cycles were run. After the last cycle of settling, the bacterial suspension C was obtained. During the domestication period, the VOCs target pollutant was toluene, and the gradient air intake load was 3000, 5000, 8000, and 10000 mg / (m 3 h) Air intake, residence time is 36s.

[0058] (4) The bacterial suspension C was expanded and cultured as follows: the bacterial suspension C was added with inorganic salt nutrient solution at a volume ratio of 1:9, aeration was started, and expanded and cultured for 48 hours to obtain VOC-degrading bacteria. During the expanded culture period, the VOCs target pollutant intake load was 10,000 mg / (m 3 ·h), the residence time is 20s.

[0059] (5) The signal molecule I (oxo-C12-HSL) was dissolved in water at a concentration of 5 μg / L and continuously sprayed to make it adhere to the surface of the filler and the internal pores. The spraying amount of the solution was 1.5 L / m 3 filler.

[0060] (6) VOC degrading bacteria are sprayed at 2L / m through the circulating water tank spray system (2). 3The filler ratio is evenly distributed in the biological filler (3) by using an intermittent spraying mode. The intermittent spraying mode is that the VOCs degrading bacteria are sprayed three times, and a 10-minute pause is made after each spraying, and the cycle is repeated until all the VOCs degrading bacteria are sprayed evenly in the biological filler (3).

[0061] (7) Toluene gas is introduced into the biological device (4). The average inlet concentration of toluene in the device is 100 mg / m 3 , residence time 36s.

[0062] (8) The circulating water tank (1) is 2L / m 3 Filler volume ratio: Add inorganic salt nutrient solution, 2mg / L Fe 3+ and 2mg / LZn 2+ The composite trace ion enhancer is dissolved and mixed evenly, and then sprayed in a drip filtration cycle for 24 hours.

[0063] (9) Dissolve the signal molecule II (furanone acyl boric acid diester) in water to a final concentration of 800 μmol / L, and spray the solution at a rate of 2 L / m 3 Filler. The signal molecule is evenly distributed in the biological device (4) by intermittent spraying. The signal molecule II is sprayed three times, and a 5-minute pause is performed after each spraying, and the cycle is repeated until all of the signal molecule is evenly distributed in the biological device (4).

[0064] (10) VOC degrading bacteria agent is sprayed at 1.5 L / m through the circulating water tank spray system (2). 3 The filler is evenly distributed in the biological filler for a second time by using an intermittent spraying mode.

[0065] (11) Add nutrient solution and 2 mg / L Fe into the circulating water tank (1). 3+ and 2mg / L Zn 2+ The composite trace ion enhancer is dissolved and mixed evenly, and then circulated and sprayed for 60 hours in a drip filtration manner.

[0066] Among them, the inorganic salt nutrient solution composition is 4.5g / LNa 2 HPO 4 12H 2 O, 1g / LKH 2 PO 4 、2.5g / LNH 4 Cl, 0.023 g / L CaCl 2 ·2H 2 O and 0.2 g / LMgCl 2 7H 2 O, the nutrient solution spraying rate is 15L / min. The biofilm formation environmental conditions of the biological device are: temperature 20-30℃, device residence time 20s, and circulating liquid pH value 6-8.

[0067] The results of the comparative test show that (please refer to Figure 4 ), the experimental group (using the method of Example 2) successfully formed biofilm on the 10th day, and the average toluene removal rate during stable operation was 91.27% ± 2.11%. The toluene removal rate of the experimental group reactor was 18.10% higher than that of the blank control group, and the biofilm start-up time was shortened by 15 days. The blank control group, referring to Example 2, was different in that signal molecule I (oxo-C6-HSL) and signal molecule II (furanone acyl boric acid diester) and 2 mg / L Fe 3+ and 2mg / LZn 2+ A complex trace ion enhancer.

Claims

1. A method for enhancing the rapid biofilm formation of efficient volatile organic compound degrading bacteria in a biological device, characterized in that: The method comprises the following steps: configuring the signal molecule I into an aqueous solution with a concentration of 1 to 5 μg / L, and using a spraying or dipping method to make it adhere to the surface of the biological device filler and the internal pore size, then evenly distributing high-efficiency volatile organic matter degrading bacteria in the biological device filler, introducing volatile organic matter gas into the biological device, and circulating liquid containing inorganic salt nutrient solution and composite trace ion enhancer in a dripping manner. After spraying for 24 hours, configuring the signal molecule II into a solution with a concentration of 500 to 1000 μmol / L, and using an intermittent spraying method to make it evenly distributed in the biological device, and then introducing high-efficiency volatile organic matter degrading bacteria into the biological device filler. The biodegrading bacteria are evenly distributed in the biological filler for the second time, and the circulating liquid containing the inorganic salt nutrient solution and the composite trace ion enhancer is continuously sprayed in a dripping manner for more than 48 hours until the biofilm is successfully formed; the signal molecule I is N-acylhomoserine lactone, selected from one of C10-HSL, C12-HSL, oxo-C6-HSL, oxo-C8-HSL, and oxo-C14-HSL; the signal molecule II is furanone acyl boric acid diester; the inorganic salt nutrient solution includes 3.0-4.5g / LNa2HPO4·12H2O, 0.7-1g / L KH2PO4, 1.5-2.5g / LNH4Cl, 0.015-0.023g / L CaCl2·2H2O and 0.1-0.2g / L MgCl2·7H2O.

2. The method according to claim 1, characterized in that The dosage of signal molecule I solution is 1-2 L / m 3 filler.

3. The method according to claim 1, characterized in that The spraying amount of signal molecule II solution is 1-2 L / m 3 filler.

4. The method according to claim 1, characterized in that The spraying rate of inorganic salt nutrient solution is 10-15L / min.

5. The method according to claim 1, characterized in that The method of uniformly distributing the high-efficiency volatile organic compound degrading bacteria in the biological device filler is to use an intermittent spraying mode to spray the high-efficiency volatile organic compound degrading bacteria in the biological device filler through the biological device spraying system. The high-efficiency volatile organic compound degrading bacteria is sprayed 3 to 5 times, and a 10-minute break is made after each spraying. The cycle is repeated until all the volatile organic compound degrading bacteria are sprayed uniformly in the biological filler. The addition ratio of the volatile organic compound degrading bacteria is 1 to 2 L / m 3 filler.

6. The method according to claim 1, characterized in that The composite trace ion enhancer includes a total ion concentration of 4 to 10 mg / L Fe 3+ 、Zn 2+ Mg 2+ At least two of the above are selected from two or more of ferric chloride, ferric sulfate, zinc chloride, zinc sulfate and magnesium chloride.

7. The method according to claim 1, characterized in that Volatile organic matter gas is introduced into the biological device, and the air intake load is 50% to 100% of the designed air intake load; the volatile organic matter includes benzene series, methyl mercaptan, and esters.

8. The method according to claim 1, characterized in that The biofilm formation conditions are: temperature 20-35°C, device residence time>15s, and circulating liquid pH value 6-8.

9. The method according to claim 1, characterized in that: The highly efficient volatile organic compound degrading bacteria are obtained by the following method: (1) The filler in the existing biofiltration device is immersed in water, and the filler is intermittently ultrasonically pretreated in batches using an ultrasonic water bath oscillator to peel off the biofilm. Then, the filler and impurities are filtered using a 20-mesh screen to separate the biofilm suspension for later use. An equal volume of inorganic salt nutrient solution is added to the biofilm suspension, and the bacterial suspension A is obtained after culturing under air immersion for 24 hours; (2) The bacterial suspension A is uniformly mixed with the aerobic activated sludge of the chemical park sewage plant in a volume ratio of (1-2):1 to obtain the bacterial suspension B, which is used as the bacterial source of the VOC degrading bacterial agent; (3) domesticating the bacterial suspension B in the following manner: first, adding the bacterial suspension B and the inorganic salt nutrient solution into the bacterial fermentation tank, the volume ratio of the bacterial suspension B to the inorganic salt nutrient solution being 1:(3-5), and the liquid level at this time is recorded as the initial liquid level; Start aeration for 34 hours, let it stand and settle for 2 hours, drain 1 / 2 to 1 / 3 of the supernatant, add 1 / 2 to 1 / 3 of the inorganic salt nutrient solution to the initial liquid level, run for 2 cycles, then shorten the aeration time to 23 hours, let it stand and settle for 1 hour, run for 2 cycles, and after the last cycle of standing and settling, obtain bacterial suspension C. (4) The bacterial suspension C is expanded and cultured as follows: the bacterial suspension C is added with an inorganic salt nutrient solution at a volume ratio of 1:9, aeration is started, and the expanded culture is carried out for 36 to 48 hours to obtain highly efficient volatile organic compound degrading bacteria.

10. The method according to claim 1, characterized in that The intermittent ultrasonic pretreatment in step (1) is carried out in batches, each batch of filler is not more than 5L, each batch of ultrasound has a total of 10 cycles, each cycle includes ultrasound for 20 to 50 seconds, and standing for 10 to 40 seconds. The total time of ultrasound and standing time in each cycle is 60 seconds, the ultrasonic power is 1000W / 40%, the temperature is 20°C, and the oscillation speed is 120r / min.

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