CN114053863A

CN114053863A - Method for constructing and quickly starting fungus-bacterium mixed biological filter bed

Info

Publication number: CN114053863A
Application number: CN202111458791.9A
Authority: CN
Inventors: 翟建; 姜春华; 芦洪涛; 赵广银; 赵晨曦; 包菁尧
Original assignee: Shanghai Urban Construction Vocational College
Current assignee: Shanghai Urban Construction Vocational College
Priority date: 2021-12-02
Filing date: 2021-12-02
Publication date: 2022-02-18

Abstract

The invention discloses a method for constructing and quickly starting a fungus-bacterium mixed biological filter bed, and belongs to the technical field of VOCs treatment. The method adopts a two-step method to realize the construction and the quick start of the fungus-bacterium mixed biological filter bed, and specifically comprises the following steps: (1) inoculating activated sludge in a filter bed, and simultaneously adding an external carbon source I into a nutrient solution of the filter bed to finish the quick start of the bacterial filter bed; (2) on the basis of the bacterial filter bed, the pH value of the nutrient solution is adjusted, meanwhile, antibiotics and an external carbon source II are added, and when the copy number ratio F/B of fungi to bacteria in a reactor is more than 0.27, the construction and the starting of the fungal-bacterial mixed biological filter bed are completed. The invention adopts a two-step method to construct and quickly start the fungus-bacterium mixed biological filter bed, does not need to change the structure of the traditional biological filter bed, does not need to add fungus strains and chemical reagents additionally, and has convenient operation and low cost.

Description

Method for constructing and quickly starting fungus-bacterium mixed biological filter bed

Technical Field

The invention relates to the technical field of VOCs treatment, in particular to a method for constructing and quickly starting a fungus-bacterium mixed biological filter bed.

Background

Volatile Organic Compounds (VOCs) can react photochemically with nitrogen oxides to form photochemical smog; can also react with oxidants such as OH, NO, O and the like in the atmosphere in multiple ways to generate secondary organic aerosol which becomes an important precursor and participant for influencing regional composite atmospheric pollution. Complicated and large-flow VOCs (volatile organic compounds) discharged in the production process of industries such as petroleum, chemical engineering, printing, coating, electroplating, textile and the like>1000m³H) low concentration of (<10g/m³) The concentration fluctuation is strong, the device has the characteristic of periodic discharge, has no recovery value, is harmful to the health and ecological environment of people, and plays a key role in improving the quality of atmospheric environment by effectively treating the device. At present, the treatment of large-air-volume and low-concentration VOCs gas becomes an urgent problem to be solved in the control of atmospheric pollution, and is also a research hotspot and difficulty in the field of domestic and foreign waste gas treatment.

Compared with the traditional physical-chemical method, the biological filtration technology has the characteristics of low investment and operation cost, high performance, environmental friendliness and the like, and is one of the best end treatment technologies for industrial source VOCs with characteristics of large air volume and low concentration. Ottengraf, Baltzis, Alonson et al believe that a complete water film exists on the surface of the traditional filter bed biofilm, gaseous VOCs firstly pass through the water film through diffusion and then enter the surface and the interior of the biofilm to be degraded by microorganisms, and therefore, the theory of phase III (gas, water and biofilm), namely absorption-biofilm, is proposed. The "absorption-biofilm" theory essentially involves two processes, namely the mass transfer process and the metabolic process of VOCs. Firstly, VOCs contact with nutrient solution or a biological membrane, and enter a biological phase from a gas phase through a liquid phase; then, VOCs are metabolized as energy and carbon sources by mainly utilizing the degradation capability of different microorganisms in the biological phase to generate carbon dioxide and water, and a small part of the carbon dioxide and water is converted into biomass, so that the aim of purification is fulfilled. According to the theory, the hydrophilicity and hydrophobicity of VOCs determine whether the VOCs can realize mass transfer from a gas phase to a biological membrane phase through a liquid phase, and the removal performance of the reactor is influenced. The hydropathic and hydrophobic properties of VOCs can be roughly classified according to henry constants: hydrophilic VOCs with a Henry constant of less than 0.1, such as dichloroethane, ethyl acetate; VOCs with a Henry constant of 0.1-0.99 and can be classified as moderate hydrophobicity, such as benzene series, dichloromethane and the like; a henry coefficient greater than 1 may be considered hydrophobic VOCs such as ethylene, methane, etc. For the traditional biotechnology, the higher the henry coefficient of the VOCs, the stronger the hydrophobicity and the poorer the mass transfer effect, so that the bioavailability and the degradation rate of the reactor are lower and the treatment effect is less desirable.

In order to improve the removal performance of the biological filter bed on hydrophobic VOCs, researchers have conducted related researches in five aspects of increasing pretreatment, introducing hydrophilic VOCs for co-metabolism, adding a surfactant, improving the structure of the biological filter bed, introducing fungi and the like in recent years. Compared with other four technologies, the fungal biological filter bed can directly capture hydrophobic VOCs from a gas phase due to the huge specific surface area of hypha, directly transfer mass from the gas phase to a biological phase without passing through a liquid phase, can better solve the problem of poor mass transfer of the hydrophobic VOCs, does not need to add chemical agents or modify the structure of the filter bed, and can also play a role in removing the hydrophobic VOCs even under adverse environmental conditions (such as low moisture content, low pH value and impact load). The inlet load of n-hexane is 140g/m³Under the condition of h, the removal capacities of the fungus filter bed and the bacteria filter bed are respectively 100 g/m and 60g/m³h. The maximum capacity of the fungus filter bed for removing toluene is 258-270 g/m³h (the removal rate is 95%) is 2-7 times of that of the bacterial filter bed. However, fungi have a slow growth rate compared to bacteria, are not sufficiently abundant in degrading strains, and often have filamentous structures which cause an increase in pressure drop in the reactor, eventually leading to channeling and clogging problems, and also produce spores which are harmful to human health. Liu et al first proposed the concept of a "fungus-bacteria coupled biofiltration system" and used this process for malodor control. The research result shows that under the condition that the EBRT is 20s,H₂the removal rate of S was 95%, and the removal ability was 60g H₂S m³The maximum removal capacity reaches 170g H₂S m³The pressure drop is 5-15 mm H₂And O. Cheng et al compared the performance of bacterial, fungal, and fungal-bacterial hybrid biofilters in treating toluene off-gas. The research result shows that the removal rates of the fungi filter, the bacteria filter bed and the fungi-bacteria mixed biological filter bed to the toluene are respectively as follows under the same condition<20％、>60％、>90 percent, the mineralization rate of the fungus filter bed to toluene is 2/3 of the bacteria filter bed and 1/2 of the fungus-bacteria mixed biological filter bed respectively. Compared with a bacterial and fungal filter bed, the fungus-bacteria mixed biological filter bed has higher removal rate and mineralization rate of the toluene. In the existing literature reports, the starting and the construction of the fungus-bacterium mixed biological filter bed are usually completed by a method for inoculating target pollutant special degradation fungi into the traditional biological filter bed. Compared with the special degradation fungi and bacteria of the inoculated target pollutants, the capacity of acquiring a carbon source and the growth rate are both low, and if the operation parameters are improperly controlled, the growth and the propagation of the carbon source are inhibited, so that the performance failure of the reactor is easily caused. Furthermore, the literature reports that the start-up method requires the inoculation of different species of fungi depending on the different target degradants. Meanwhile, the slow growth speed of the fungi also causes the start-up period of the fungus-bacteria mixed biological filter bed to be overlong. Therefore, it is highly desirable to construct a fungal-bacterial mixed biofilter bed with the characteristics of simple operation, short start-up period, high removal efficiency, etc. for use in the treatment of VOCs.

Disclosure of Invention

The invention aims to provide a method for constructing and quickly starting a fungus-bacterium mixed biological filter bed, which aims to solve the problems in the prior art.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a method for constructing and quickly starting a fungus-bacterium mixed biological filter bed, which realizes the construction and quick start of the fungus-bacterium mixed biological filter bed by adopting a two-step method and specifically comprises the following steps:

(1) inoculating activated sludge in a filter bed, and simultaneously adding an external carbon source I into a nutrient solution of the filter bed to finish the quick start of the bacterial filter bed;

(2) on the basis of the bacterial filter bed, the pH value of the nutrient solution is adjusted, meanwhile, antibiotics and an external carbon source II are added, and when the copy number ratio F/B of fungi to bacteria in a reactor is more than 0.27, the construction and the starting of the fungal-bacterial mixed biological filter bed are completed.

Preferably, the inoculation concentration of the activated sludge is 2500-3500mg VSS/L.

Preferably, in the step (1), the concentration of the exogenous carbon source I in the nutrient solution is 0-500 mg/m³And the exogenous carbon source I is benzyl alcohol.

Preferably, the concentration of benzyl alcohol in the nutrient solution is 300mg/m³。

Preferably, in the step (2), the concentration of the external carbon source II in the nutrient solution is 0-500 mg/m³And the exogenous carbon source II is wheat bran.

Preferably, the concentration of wheat bran in the nutrient solution is 100mg/m³。

Preferably, in the step (2), the concentration of the antibiotics in the nutrient solution is 20-50 g/m³And the antibiotic is chloramphenicol.

Preferably, the concentration of chloramphenicol in the nutrient solution is 20g/m³。

Preferably, the pH is 5.9.

The invention also provides the application of the method in the treatment of toluene.

The invention discloses the following technical effects:

fungi in the reported fungi-bacteria biofilter bed play a role in capturing and degrading hydrophobic VOCs, and the degrading effect of the fungi-bacteria biofilter bed does not have broad spectrum, namely different types of fungi need to be inoculated aiming at different hydrophobic VOCs. The fungus-bacterium mixed biological filter bed fully exerts the advantages of strong fungus adsorption capacity and high bacterium biological diversity, the fungus is mainly responsible for adsorbing various VOCs and conveying the VOCs from a gas phase to a biological phase, and the bacterium in the biological phase mainly plays a role in degradation.

Compared with the starting mode of the biological filter bed in the prior art, the method has the advantage that the phenomenon that the performance of the reactor is reduced due to the weak carbon source competition ability caused by fungus inoculation does not exist.

Compared with the fungus-bacterium mixed biological filter bed and the traditional biological filter bed in the prior art, the invention has stronger VOCs load fluctuation resistance, the starting period of the invention is only 15 days, the toluene removal rate is 93.0 percent, the mineralization rate is 77.6 percent, and meanwhile, the delta P/H is stabilized at 5.0cm H₂And O/m. Therefore, the method has the advantages of short toluene removal period, high removal efficiency and wide application value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a graph showing the effect of an inoculated bacterial source on the start-up period of a bacterial filter bed and the removal rate of toluene; ". tangle-solidup" toluene inlet concentration; "Δ" toluene exit concentration; "●" toluene removal;

FIG. 2 is an analysis of the inoculum source at the phylum and genus level; (a) analyzing the level of a bacterial phylum; (b) analyzing the level of the bacterial genus;

FIG. 3 is a thermograph of the prediction of the contaminant degradation function of four inoculated activated sludge from PICRUSt;

FIG. 4 is a graph showing the effect of inoculum source on toluene removal capacity in a bacterial filter bed; "■" toluene removal capability; "●" carbon dioxide generation; ". tangle-solidup" mineralization rate;

FIG. 5 is a graph showing the effect of YZ-inoculated activated sludge concentration on the start-up period of the bacterial filter bed and the removal rate of toluene; ". tangle-solidup" toluene inlet concentration; "Δ" toluene exit concentration; "●" toluene removal;

FIG. 6 is a graph showing the effect of the type and concentration of an exogenous carbon source on the start-up period of a bacterial filter bed and the removal rate of toluene;

FIG. 7 is a graph of the effect of pH on fungal-bacterial mixed biofilter start-up period, toluene removal rate, mineralization rate, log absolute copy number of fungi and bacteria in the biofilm, pressure drop, and fungal community structure at the genus level; (a) a start cycle; (b) the toluene removal rate; (c) the mineralization rate; (d) log absolute copy number of fungi and bacteria in the biofilm; (e) pressure drop; (f) fungal community structure at the genus level;

FIG. 8 is a graph of the effect of antibiotic type and concentration on the start-up period, toluene removal rate, and mineralization rate of a fungal-bacterial mixed biofilter bed; (a) adding 50g m^-3Influence of chloramphenicol, gentamicin sulfate and no antibiotics on the start-up period and the toluene removal rate of the fungus-bacterium mixed biological filter bed; (b) adding 50g m^-3Influence of chloramphenicol, gentamicin sulfate and no antibiotics on the start-up period of the fungus-bacterium mixed biological filter bed and the mineralization rate of toluene; (c) adding 50g m^-3Chloramphenicol, 20g m^-3Influence of chloramphenicol and no antibiotics on start-up period and toluene removal rate of the fungus-bacterium mixed biological filter bed; (d) adding 50g m^-3Chloramphenicol, 20g m^-3The effect of chloramphenicol and no added antibiotics on the start-up period of the fungal-bacterial mixed biofilter and the rate of toluene mineralization.

FIG. 9 is a graph of the effect of exogenous carbon source type and concentration on the start-up period and toluene removal rate of a fungal-bacterial mixed biofilter; (a) adding different external carbon sources (TOC 300mg m)^-3Wheat bran and benzyl alcohol) and no external carbon source are added to influence the start cycle and the toluene removal rate of the fungus-bacterium mixed biological filter bed; (b) adding different amounts of wheat bran (

TOC

0, 100, 300 and 500mg m)^-3) Influence on start-up period and toluene removal rate of the fungus-bacteria mixed biofilter.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The specification and examples are exemplary only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The design idea of the invention is as follows: the fungus-bacterium mixed biological filter bed is quickly started by adopting a two-step method, namely, the bacterium filter bed is quickly started firstly, and the construction and the starting of the fungus-bacterium mixed biological filter bed are carried out on the basis. The filler is polyurethane foam block with side length of 4-6mm and bulk density of 0.015g cm^-3Water holding capacity 55g-H₂O g^-1Porosity of 95%, average pore diameter of 0.8mm, surface area of 73.65m² g^-1. The nutrient solution contains 0.5g K per liter₂HPO₄、0.1g MgSO₄·7H₂O、4.5g KH₂PO₄、2g NH₄Cl and 2mL vitamins and trace elements. Firstly, a gas-liquid circulation dynamic membrane hanging method is adopted to start the bacterial filter bed. Under the same experimental conditions, different activated sludge with the same VSS/L and the same activated sludge with different VSS/L are uniformly sprayed to a filler layer from top to bottom at a flow rate of 0.5L/min by a peristaltic pump, and biofilm formation is carried out on a biological filter bed. The toluene waste gas passes through the packing layer from bottom to top and then undergoes the acclimation stage (the toluene concentration is 300 +/-10 mg/m)³) Growth phase (toluene concentration 500 + -15 mg/m)³) And a steady-state operation phase (toluene concentration 1000. + -. 112 mg/m)³). In the acclimatization stage, when the biofilm can be obviously seen on the surface of the filler, the biofilm formation is determined to be finished; when the toluene removal rate reaches 85%, the acclimatization and the start-up are determined to be completed. Under the same experiment conditions, activated sludge with short starting period and high toluene removal performance is selected as the optimal inoculation strain and concentration. Then, a method of coupling low pH value with antibiotics is adopted to construct a fungus-bacterium mixed biological filter bed on the basis of the bacterial filter bed. The low pH value and the addition of antibiotics can inhibit the growth of bacteria and promote the propagation of fungi. When the ratio of the fungal/bacterial copy number is greater than 0.27, the fungal-bacterial mixed biofilter bed construction is deemed complete. The method of adding an external carbon source is adopted to accelerate the start of the fungus-bacterium mixed biological filter bed. The optimum pH value, the type and concentration of antibiotics and the type and concentration of an external carbon source are determined by taking the start-up time and the toluene removal performance of the fungus-bacterium mixed biological filter bed as evaluation standards.

Example 1

After inoculation of 2500mg of VSS/L of activated sludge from four different sources, the start-up period of the bacterial filter bed and the removal rate of toluene in the acclimation, growth and stabilization stages were determined.

As shown in fig. 1, when the nail is wornThe benzene concentration is 500 +/-15 mg/m³Bacterial filter beds inoculated with YZ (Yangzi petrochemical), NG (Nanjing Steel works), HY (North China pharmaceutical) and HH (Huaihe chemical) activated sludge respectively had average toluene removal rates of 91.2%, 91.7%, 83.3% and 91.1%, respectively. When the concentration of the toluene is 500 +/-15 mg/m³Increased to 1000 + -112 mg/m³The average removal rate of toluene by the biological filter bed is 85.6%, 85.2%, 80.3% and 85.4%, and the corresponding start-up periods are 15, 20, 24 and 15 days. From this, it can be seen that the start-up period of the bacterial filter bed inoculated with YZ and HH activated sludge was 15 days at the shortest.

Example 2

The colony structures of YZ (Yangzhi petrochemical industry), NG (Nanjing Steel works), HY (North China pharmaceutical industry) and HH (Huaihe chemical industry) activated sludge on phyla and genus levels of bacteria and fungi are analyzed and compared by an Illumina Miseq high-throughput sequencing method.

As shown in fig. 2: the bacteria in YZ activated sludge are mainly distributed in Proteobacteria (Proteobacteria), Bacteroidetes (Bacteroides) and Acidobacterium (Acidobacterium), and the relative abundance is 47.96%, 28.02% and 9.24% respectively; the relative abundances of Proteobacteria, Acidobacter and deinococcus-Thermus in NG activated sludge are 44.90%, 33.27% and 11.18% respectively; relative abundances of Chlorobia, Proteobactera and Bacteroides in HY activated sludge are 37.37%, 25.41% and 22.78%, respectively; while the relative abundances of Proteobacteria, Candidate _ division _ TM7 and bacteroides in HH-activated sludge were 25.73%, 16.21% and 15.86%, respectively. The four inoculated activated sludge have the function of degrading toluene. The most abundant genera among YZ, NG, HY and HH activated sludge were Thauera (18.1%), blatocatela (33.2%), Thauera (4.1%) and Nitrospira (12.6%), respectively. Of these, Thauera is a recognized toluene-degrading bacterium with relative abundances of 1.08%, 2.71% in NG and HH activated sludge, respectively. Nitrospira can degrade the mixed waste gas of toluene, methyl mercaptan and alpha-pinene, and the proportion of the methyl mercaptan in NG activated sludge is 4.76%. From this, it can be explained that bacteria belonging to Thauera in YZ activated sludge, bacteria belonging to Nitrospira and Thauera in NG activated sludge, bacteria belonging to Thauera in HY activated sludge, and bacteria belonging to Nitrospira and Thauera in HH activated sludge play a key role in the process of degrading toluene off-gas, and the relative abundances of bacteria having toluene degradation function are YZ (18.1%), HH (15.31%), NG (5.84%) and HY (4.1%), respectively.

Example 3

Based on the results of high throughput sequencing of the 16S rRNA gene, picrast predicted the metabolic function of bacteria in different inoculated sludges.

As shown in fig. 3, the analysis found that the toluene degradation functions of the four seeded activated sludge were very similar. The relative abundance of YZ activated sludge is higher for the benzoic acid degradation function than the other three. This indicates that the higher the relative abundance of the benzoic acid degrading function in the activated sludge, the shorter the start-up period of the bacterial filter bed, and the shortest the start-up period of the bacterial filter bed inoculated with YZ activated sludge.

Example 4

The toluene removal capacity was 70.5. + -. 2.3g/m³And h, respectively inoculating YZ, NG, HY and HH activated sludge to the bacterial filter bed, and analyzing the carbon dioxide yield and the mineralization rate of the methylbenzene of the bacterial filter bed.

As shown in FIG. 4, the carbon dioxide productivity of the bacterial filter bed was 198.4. + -. 8.9, 167.8. + -. 6.6, 147.0. + -. 9.0 and 188.1. + -. 8.6g/m, respectively³h, the mineralization rates of the p-toluene are 72.1, 61.3, 53.0 and 68.8 percent respectively. The indexes of the start-up period of the bacterial filter bed, the toluene removal performance, the mineralization rate and the like are comprehensively compared, and YZ activated sludge as an inoculation bacteria source shows good performance.

Example 5

The concentration of the toluene at the inlet is 1000 +/-112 mg/m³Under the conditions of (1), inoculating activated sludge with different concentrations of YZ, and analyzing the influence of the inoculation concentration of the YZ activated sludge on the start-up period of a bacterial filter bed and the removal rate of methylbenzene.

As shown in FIG. 5, the YZ activated sludge with the concentration of 2500mg and 3500mg VSS/L is inoculated, the toluene removal rate can reach 85-88% on the 15 th day, and the start of the bacterial filter bed is completed. The removal rate of toluene only reaches 72% at 24 days by adopting 1500mg VSS/L of inoculated sludge. And the inoculation sludge with 500mg VSS/L is adopted, the acclimation period is longer, the toluene removal rate is lower, and the toluene removal rate is only 40% after 35 days of acclimation. This indicates that too low a concentration of inoculated sludge results in sludge loss and a failed start-up of the reactor. Therefore, the optimal inoculation concentration of YZ activated sludge is 2500mg VSS/L.

Example 6

The concentration of the toluene at the inlet is 1000 +/-112 mg m^-3Inoculation of 2500mg of VSS L^-1And analyzing the influence of the type and concentration of an external carbon source on the start-up period of the bacterial filter bed and the removal rate of the toluene under the condition of YZ activated sludge.

As shown in FIG. 6, under the condition of no addition of external carbon source, the toluene removal rate was 85.6. + -. 0.5%, and the start-up period was 15 days. Under the same experimental conditions, the TOC is added to 300mg/m³After the benzyl alcohol, the toluene removal rate increased to 88.0 ± 0.4%, while the start-up period was shortened to 10 days. However, after the xylenol isomer mixture with the same TOC is added, the toluene removal rate of the bacterial filter bed is reduced to 81.0 +/-0.3%, and the starting period is prolonged to 20 days.

With benzyl alcohol (

TOC

0, 100, 300 and 500mg/m³) The addition concentration is increased, the starting period of the bacterial filter bed is continuously shortened, and the removal rate of the methylbenzene is continuously increased. When the added TOC of the benzyl alcohol exceeds 500mg/m³After that, the start-up period of the bacterial filter bed is increased from 10 days to 15 days, and the toluene removal rate is reduced from 88.0 +/-0.4 to 81.9 +/-0.2%.

Example 7

The concentration of the toluene gas is 1000 +/-112 mg m^-3And analyzing the influence of the pH value on the start-up period, the toluene removal rate, the mineralization rate, the absolute copy number logarithm of fungi and bacteria in a biological membrane, the pressure drop and the fungal community structure on the genus level of the fungus-bacteria mixed biological filter bed under the condition of the retention time of 45 s.

As shown in FIG. 7, the pH of the nutrient solution was 5.9, and F/B was 0.89>0.27, and the removal rate of toluene during the stable operation of the biofilter is 92.0 +/-0.3 percent, and the mineralization rate is 79.1 +/-0.2 percent, which are higher than the conditions that the pH value is 7.0 and 4.0. Meanwhile, the delta P/H is stabilized at 5.0cm H₂O/m, lower than 8.3cm H at pH 4.0₂O/m, which is advantageous for the reactorAnd the operation is stable for a long time. In summary, under the condition that the pH value of the nutrient solution is 5.9, the construction and the start of the fungus-bacterium mixed biological filter bed can be determined to be completed after the toluene removal performance and the mineralization rate are stable.

Example 8

The concentration of the toluene gas is 1000 +/-112 mg m^-3And analyzing the influence of the antibiotic type and concentration on the start-up period, the toluene removal rate and the mineralization rate of the fungus-bacterium mixed biological filter bed under the conditions that the retention time is 45s and the pH value of the nutrient solution is 5.9.

As shown in FIG. 8, 50g/m was added³The fungal-bacterial mixed biofilter start-up period for chloramphenicol was 18 days, while 50g/m was added³The start-up period of the fungus-bacteria mixed biological filter bed of gentamicin sulfate is 19 days, which is respectively shortened by 2 days and 1 day compared with a reactor without any antibiotic.

Adding 50g/m of the mixture respectively³The removal rate of the fungus-bacterium mixed biological filter bed of chloramphenicol and gentamicin sulfate on toluene waste gas is hardly changed compared with that of the fungus-bacterium mixed biological filter bed without the addition of chloramphenicol. The mineralization rate sequence of the fungus-bacterium mixed biological filter bed to toluene waste gas is as follows: not added (79.1 +/-0.2%)>Adding 50g/m³Chloramphenicol (75.6 + -0.3%)>Adding 50g/m³Gentamicin sulfate (70.6 + -0.2%).

The adding concentration of the chloramphenicol is 50g/m³Down to 20g/m³The removal rate and the start-up period of the fungus-bacterium mixed biological filter bed to the toluene are not changed remarkably, and the mineralization rate of the toluene is increased from 75.6 +/-0.3 percent to 77.6 +/-0.2 percent. In summary, chloramphenicol is selected as a bacteriostatic agent, and the optimal adding concentration is 20g/m³。

Example 9

The concentration of the toluene gas is 1000 +/-112 mg m^-3The retention time is 45s, the pH value of the nutrient solution is 5.9, and the adding concentration of the chloramphenicol is 20g/m³The influence of the kind and concentration of the added carbon source on the start-up period and the toluene removal rate of the fungus-bacteria mixed biological filter bed is analyzed.

As shown in FIG. 9, the startup period of the reactor for wheat bran addition was shortened to 15 days, and benzyl alcohol was addedThe addition of the carbon source and the addition of the carbon source are kept for 18 days, and the removal rate of the toluene is 94.3 +/-0.2%, 93.9 +/-0.2% and 92.1 +/-0.3% respectively. When the wheat bran is respectively

TOC

0, 100, 300 and 500mg/m³In the method, the start cycle of the fungus-bacterium mixed biological filter bed is respectively 18 days, 15 days and 15 days, and the toluene removal rate is respectively 92.1 +/-0.3%, 93.0 +/-0.3%, 94.3 +/-0.2% and 94.8 +/-0.3%. In conclusion, considering both the performance and the running cost of the reactor, the fungus-bacteria mixed biological filter bed is started to select wheat bran as an external carbon source, and the optimal adding amount is TOC 100mg/m³。

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims

1. A method for constructing and quickly starting a fungus-bacterium mixed biological filter bed is characterized in that the construction and quick start of the fungus-bacterium mixed biological filter bed are realized by adopting a two-step method, and the method specifically comprises the following steps:

2. The method for constructing and rapidly starting a fungus-bacteria mixed biological filter bed as claimed in claim 1, wherein the inoculation concentration of the activated sludge is 2500-3500mg VSS/L.

3. The method for constructing and rapidly starting a fungus-bacteria mixed biological filter bed as claimed in claim 1, wherein in the step (1),the concentration of the exogenous carbon source I in the nutrient solution is 0-500 mg/m³And the exogenous carbon source I is benzyl alcohol.

4. The method of claim 3, wherein the benzyl alcohol concentration in the nutrient solution is 300mg/m³。

5. The method for constructing and rapidly starting the fungus-bacterium mixed biological filter bed as claimed in claim 1, wherein in the step (2), the concentration of the external carbon source II in the nutrient solution is 0-500 mg/m³And the exogenous carbon source II is wheat bran.

6. The method of claim 5, wherein the concentration of wheat bran in the nutrient solution is 100mg/m³。

7. The method for constructing and rapidly starting the fungus-bacterium mixed biological filter bed as claimed in claim 1, wherein in the step (2), the concentration of the antibiotic in the nutrient solution is 20-50 g/m³And the antibiotic is chloramphenicol.

8. The method of claim 7, wherein the concentration of chloramphenicol in the nutrient solution is 20g/m³。

9. The method of fungal-bacterial mixed biofilter construction and rapid start-up according to claim 1, wherein said pH is 5.9.

10. Use of a process according to any one of claims 1 to 9 for the treatment of toluene.