Microorganism-based waste gas treatment method and system

Abstract

The invention relates to the technical field of environmental engineering, in particular to a waste gas treatment method and system based on microorganisms. The system integrates a fungus biofilter, a bacteria bio-trickling filter and an intelligent fuzzy control system. Hydrophobic composite filler and fungal communities are adopted in the first-stage treatment, hydrophobic VOCs are directly captured through aerial hyphae, and the bottleneck of gas-liquid mass transfer is broken through; in the secondary treatment, bacterial communities are adopted, a nonionic surfactant with critical micelle concentration is added into the circulating liquid, and mass transfer is enhanced and pollutants are deeply degraded by utilizing a micelle solubilizing mechanism. The system is provided with a self-adaptive controller based on fuzzy logic, operation parameters are adjusted in real time to cope with impact loads, and filler blockage is prevented. According to the invention, the removal efficiency of refractory hydrophobic VOCs (Volatile Organic Chemicals) such as benzene series and alkane is obviously improved, and the device has the advantages of strong impact resistance, stable operation, low energy consumption and the like, and is suitable for treating complex industrial organic waste gas.

Description

Technical Field

[0001] This invention relates to the field of environmental engineering technology, specifically to a waste gas treatment method and system based on microorganisms. Background Technology

[0002] With the deepening of global industrialization, volatile organic compounds (VOCs) and odorous gases emitted during industrial production have become one of the major sources of air pollution. VOCs are not only key precursors to photochemical smog and surface ozone formation, but also promote the formation of secondary organic aerosols, profoundly impacting atmospheric visibility and climate change. Furthermore, many VOCs (such as benzene, toluene, ethylbenzene, xylene and other benzene series compounds, as well as chlorinated hydrocarbons) exhibit significant biotoxicity, teratogenicity, carcinogenicity, and mutagenicity, seriously threatening human health and ecological security.

[0003] Currently, developing efficient, economical, and environmentally friendly waste gas treatment technologies has become an urgent priority. Traditional waste gas treatment technologies are mainly divided into two categories: physicochemical methods and biological methods. Physicochemical methods include adsorption, absorption, condensation, membrane separation, thermal oxidation (incineration), and catalytic oxidation. Although these methods are highly efficient in treating high-concentration waste gases, they often face problems such as huge energy consumption, easy generation of secondary pollution, and high equipment investment and operating costs. For example, although activated carbon adsorption is widely used, its adsorption effect on high-humidity waste gases is poor, and the regeneration process is complex; scrubbing methods usually require the consumption of large amounts of chemical reagents and generate difficult-to-treat wastewater.

[0004] In contrast, biological treatment technology utilizes the physiological metabolic activities of microorganisms to absorb organic pollutants and inorganic odorous substances in waste gas as carbon, nitrogen, or energy sources, ultimately converting them into harmless or low-toxic substances such as carbon dioxide, water, sulfates, and nitrates, as well as microbial cell matter (biomass). Biological methods offer significant advantages such as low operating costs, no secondary pollution, mild operating conditions (normal temperature and pressure), and high safety, making them particularly suitable for treating large volumes of low-concentration organic waste gas and odorous gases.

[0005] Despite significant progress in biological treatment technology over the past few decades, the following key technological bottlenecks still exist in practical industrial applications and urgently need to be addressed: First, the mass transfer and degradation limitations of hydrophobic VOCs. Industrial waste gases often contain large amounts of hydrophobic VOCs (such as benzene, toluene, xylene, hexane, etc.). These substances have high Henry's constants and extremely low solubility in water. In traditional biofilters and bioscrubbers, microorganisms mainly live in biofilms or suspensions with water as the medium. According to the two-film theory, hydrophobic VOCs must cross the gas-liquid interface and the liquid film to enter the biological phase from the gas phase. The liquid film resistance becomes the rate-limiting step in the entire degradation process. In addition, the surface of traditional bacterial biofilms is highly hydrophilic, making it difficult to effectively adsorb and capture hydrophobic molecules, resulting in low removal efficiency.

[0006] Second, the control strategies suffer from lag and lack of intelligence. Most current biological waste gas treatment systems employ open-loop control or simple PID control, adjusting only the fan frequency or pump start / stop. However, biological reactions are highly nonlinear, time-varying, and lag-prone complex processes, influenced by a combination of factors such as pH, temperature, humidity, nutrient status, and the type and concentration of pollutants. Simple control strategies struggle to cope with complex dynamic changes. For example, traditional timed spraying often results in either overly wet packing material (increasing mass transfer resistance and creating an anaerobic zone) or overly dry material (microbial inactivation), failing to provide precise control based on real-time biological metabolic needs.

[0007] Third, the functional limitations of a single microbial community. Traditional biological filters typically rely on natural inoculation or a single type of activated sludge, lacking highly efficient degradative bacterial communities for specific pollutants. While bacteria have a fast metabolic rate, they are not as efficient as fungi in degrading complex aromatic hydrocarbons and in terms of acid and dryness resistance; although fungi can directly capture gaseous pollutants through aerial hyphae, their growth rate is slow and they are prone to spore dispersal. A single bacterial community is difficult to simultaneously cope with complex mixed waste gases (such as those containing both hydrophilic alcohols and ketones and hydrophobic benzene compounds).

[0008] In summary, existing biological waste gas treatment technologies have significant shortcomings in treating hydrophobic VOCs and in intelligent control. Summary of the Invention

[0009] This invention provides a microbial-based waste gas treatment method and system. Through the deep integration of an innovative fungal-bacterial two-level synergistic architecture, a surfactant-enhanced mass transfer mechanism, a modified composite biological packing material, and an adaptive fuzzy logic control system, this invention achieves efficient and stable purification of complex industrial waste gases.

[0010] A microbial-based waste gas treatment system includes a gas pretreatment module, a first-stage fungal biofilter, a second-stage bacterial biotrickling filter, and a control module. The gas pretreatment module is used to pretreat the industrial waste gas entering the system. It is configured to remove particulate matter from the waste gas and adjust the waste gas temperature to 15-35℃ and the relative humidity to above 90%, thereby providing a suitable microbial growth environment for subsequent biological treatment. The first-stage fungal biofilter is configured as an upflow reactor, filled with hydrophobic composite packing material, inoculated with a degradation community mainly composed of filamentous fungi, and operates under continuous gas phase and intermittent liquid phase spraying conditions. It is used to directly capture and degrade hydrophobic volatile organic compounds in the gas phase through the aerial hyphae of fungi. The second-stage bacterial bio-trickling filter is configured as a counter-current reactor, filled with inert porous packing material, inoculated with a mixed bacterial community mainly composed of bacteria, and equipped with a circulating nutrient solution spraying system containing a surfactant dosing device. This system uses surfactant solubilization and bacterial bio-oxidation to remove residual hydrophobic volatile organic compounds, hydrophilic volatile organic compounds, and malodorous gases. The control module is used to automatically adjust the spraying frequency, nutrient solution dosage and surfactant concentration based on real-time monitored gas concentration, pressure drop and circulating liquid parameters. This includes: a sensor array collecting gas concentration, pressure drop and circulating liquid parameters, and a controller using a built-in fuzzy inference engine to control the system based on the data collected by the sensor array.

[0011] Preferably, the hydrophobic composite filler is prepared by mixing and curing the following raw materials in volume percentages: 30%-40% compost or humus, 20%-30% perlite or vermiculite, 10%-15% cement or sodium silicate binder, 15%-25% biochar or hydrophobically modified zeolite, and 1%-5% calcium carbonate buffer; The preparation process of the filler includes adding aluminum powder foaming agent to the mixed raw materials so that the cured filler has a multi-level pore structure, wherein the porosity is greater than 60% and the specific surface area is greater than 400m² / m. The surface of the filler has hydrophobic properties and a slightly acidic environment suitable for the attachment and growth of fungal aerial hyphae.

[0012] Preferably, the filamentous fungal community inoculated in the first-stage fungal biofilter is composed of the following parts by weight of fungal strains: 30-50 parts of Fusarium solanum, 20-40 parts of Hydnocarpus syringae, and 10-30 parts of Hydnocarpus spp. The microbial community was obtained by domestication in an acidic culture medium containing a hydrophobic carbon source, enabling it to produce a large number of aerial mycelia in an environment with a relative humidity of 40%-60%.

[0013] Preferably, the second-stage bacterial bio-trickling filter tower is filled with an inert porous packing material, which is selected from one or more combinations of polyurethane foam cubes, polypropylene multifaceted hollow spheres or volcanic rock, and has a specific surface area of ​​greater than 500 m / m and a porosity of greater than 90%. The mixed bacterial flora inoculated in the second-stage bacterial bio-trickling filter includes: *Pseudomonas putida*, used to degrade benzene compounds; *Thiobacillus denitrificationus*, used to oxidize hydrogen sulfide; and *Rhodococcus*, used to assist in the adsorption and degradation of hydrophobic alkanes. The trickling filter is configured for gas-liquid countercurrent operation, with the pH value of the circulating spray liquid controlled at 6.5-7.5 and the liquid spray density controlled at 2-10 m / mh.

[0014] Preferably, the surfactant dosing device is used to add a nonionic surfactant, preferably polysorbate 80, to the circulating nutrient solution of the second-stage bacterial biofilter; and the control system is configured to maintain the concentration of the surfactant in the circulating solution between 15 mg / L and 65 mg / L, i.e., near the critical micelle concentration of the surfactant, so as to utilize the micelle solubilization effect to promote the transfer of hydrophobic pollutants from the gas phase to the liquid phase biofilm.

[0015] Preferably, the control module includes an anti-impact load adaptive control logic, specifically: when the rate of change of the inlet exhaust gas load exceeds a preset threshold, it automatically switches to impact mode, controls the circulation pump to increase the spray flow rate, and controls the dosing pump to increase the dosage of surfactant and nutrient solution until the outlet removal rate recovers to the steady-state target value.

[0016] A microbial-based waste gas treatment method includes the following steps: The industrial waste gas to be treated is passed through a heat exchanger or humidification chamber to adjust the temperature to 15-35°C and the relative humidity to above 90%, and to remove particulate matter. The pretreated waste gas is passed into the first-stage fungal biological filter, and the pH of the packing layer is controlled at 4.0-5.5. The aerial mycelium of fungi directly adsorbs and degrades the hydrophobic organic compounds in the waste gas. The exhaust gas treated by the first-stage fungal biofilter is passed into the second-stage bacterial bio-trickling filter tower. The pH of the circulating liquid is controlled at 6.5-7.5, and the concentration of polysorbate 80 in the circulating liquid is maintained near the critical micelle concentration. The remaining hydrophobic organic compounds, hydrophilic organic compounds and malodorous gases are removed by the solubilization of surfactants and the biological oxidation of bacteria. The controller in the control module monitors the system pressure drop, pH value, and organic compound removal rate in real time; when the pressure drop is too high, backwashing or biomass reduction strategies are executed; when the pH deviates, acid or alkali is added automatically; and when there is a load shock, spraying and solubilization are automatically enhanced.

[0017] Compared with the prior art, the advantages of this invention are: By employing a dual mechanism of direct gas-phase uptake by fungal aerial hyphae and liquid-phase solubilization by surfactant micelles, the problem of limited gas-liquid mass transfer was solved, thereby improving the removal efficiency of hydrophobic volatile organic compounds such as hexane and toluene.

[0018] In the first-stage fungal biofilter, the biochar component in the composite packing provides physical adsorption buffering capacity, enabling adsorption peak reduction under high load and desorption regeneration under low load. Combined with the rapid response mechanism of the control module, the system can still maintain a high and stable removal rate under load fluctuations and intermittent operation conditions.

[0019] By combining fungal biofilters and bacterial biotrickling filters, fungi degrade difficult-to-treat substances, bacteria deeply mineralize and maintain environmental pH stability, significantly reducing the risk of secondary pollution. Attached Figure Description

[0020] Figure 1 This is a flowchart of a microbial-based waste gas treatment method proposed in this invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] The present invention discloses a microbial-based waste gas treatment system, which includes, in sequence along the waste gas flow direction: a pretreatment adjustment module, a first-stage fungal biofilter, a second-stage bacterial bio-trickling filter, an exhaust stack, and a control module running through the entire system.

[0023] The pretreatment and regulation module is used to pretreat the industrial waste gas entering the system, including particulate matter removal and temperature and humidity regulation, specifically: Dust removal and temperature control: The exhaust gas first enters a spray scrubbing tower or cyclone dust collector to remove particulate matter (PM) and oil mist, preventing clogging of the biological packing material. For exhaust gas with a temperature exceeding 4°C, it is cooled to the suitable range of 15-35°C for microorganisms by a shell-and-tube heat exchanger or spray cooling.

[0024] Humidification adjustment: Although the first-stage fungal filter has good dryness resistance, the relative humidity (RH) of the exhaust gas needs to be adjusted to 90%-95% in order to maintain basic physiological activity. This is usually achieved through a humidification chamber equipped with high-pressure micro-mist nozzles.

[0025] The main function of this module is to regulate the state of the exhaust gas to accommodate the growth of microorganisms.

[0026] The first-stage fungal biofilter is used to directly capture and degrade hydrophobic volatile organic compounds in the gas phase through fungal aerial hyphae. In this filter, the reactor body is made of acid-resistant fiberglass (FRP) or stainless steel and is designed as an upflow structure, allowing gas to enter from the bottom and pass through the packing layer.

[0027] The packing layer employs a hydrophobic modified composite packing, designed to address the problems of easy compaction and short lifespan associated with traditional packings, and to provide a hydrophobic surface. Its formulation (by volume ratio) and preparation process are as follows: Components: Compost / humus (30%-40%): Provides natural sources of microorganisms, abundant organic matter and trace elements, serving as a seed bank for microbial initiation.

[0028] Perlite / vermiculite (20%-30%): As an inorganic framework, it provides high porosity and water retention, prevents bed collapse, and reduces bulk density.

[0029] Cement / sodium silicate binder (10%-15%): binds loose organic and inorganic materials into particles with a certain mechanical strength (particle size 10-20mm) to prevent crushing and loss during long-term operation.

[0030] Biochar / hydrophobically modified zeolite (15%-25%): Provides a large specific surface area and hydrophobic adsorption sites. Biochar can not only adsorb hydrophobic volatile organic compounds, acting as a buffer to smooth load fluctuations, but also promote interspecific electron transfer and improve metabolic efficiency.

[0031] Preparation method: Mix the above raw materials evenly, add appropriate amount of water and foaming agent (such as aluminum powder or hydrogen peroxide) to increase the pore structure, granulate by extrusion or mold forming, and then cure and dry to obtain the filler. This filler has a water holding capacity of >50% and a specific surface area of ​​>400 m² / m.

[0032] The inoculum should be a specially acclimatized fungal community, including but not limited to Fusarium solani, Phialophorasp., Exophialaoligosperma, and Cladosporium sphaerospermum.

[0033] These fungi possess well-developed aerial hyphae and can secrete hydrophobic proteins, significantly reducing gas-liquid interface resistance and directly uptake hydrophobic substrates such as benzene, toluene, and ethylbenzene from the gas phase. Furthermore, fungi exhibit far greater tolerance to low pH (3-5) and dry environments than bacteria, making them suitable for operation under conditions of high initial load and significant environmental fluctuations.

[0034] This filter specifically operates in: Humidity: Control the moisture content of the packing material to 40%-60%. Unlike bacteria, which require a water-soaked environment, fungi prefer a moist but unsaturated environment to facilitate the growth of aerial mycelia.

[0035] Nutrition: Intermittent spraying is used. A mineral salt solution containing nitrogen, phosphorus and trace elements is added to the spray solution, and a small amount of acidic buffer solution can be added to maintain the pH at 4.0-5.5 to inhibit bacterial growth competition at the first stage.

[0036] The second-stage bacterial bio-trickling filter is connected in series after the fungal filter for deep purification, degrading hydrophobic volatile organic compounds, hydrophilic volatile organic compounds, malodorous gases, and intermediate products produced by fungal metabolism that were not completely removed by the first-stage fungal biofilter. It is designed with a gas-liquid countercurrent structure.

[0037] The packing system uses inert, high specific surface area structured or random packing materials, such as polyurethane foam (PUF) cubes, multifaceted hollow spheres, or volcanic rock. PUF has extremely high porosity (>95%) and good biofilm formation performance, making it particularly suitable for bacterial bio-trickling filters.

[0038] The inoculation agent should be a broad-spectrum mixed bacterial group, including but not limited to: Pseudomonas putida (efficiently degrades benzene series compounds), Bacillus subtilis, Thiobacillus sp. (used to remove H2S), and Rhodococcus sp. (with hydrophobic cell walls, which assist in the degradation of alkanes).

[0039] In a preferred embodiment, a nonionic surfactant, Tween 80 (polysorbate 80), is also added to the circulating spray liquid of the trickling filter to enhance proton transfer.

[0040] When the Tween 80 concentration reaches or slightly exceeds its critical micelle concentration (approximately 0.012 mM, or about 15 mg / L), surfactant molecules self-assemble into micelles in water. Micelles possess a hydrophilic outer shell and a hydrophobic core, enabling them to encapsulate sparingly soluble hydrophobic volatile organic compounds within the core, thereby increasing their apparent solubility in the liquid phase by several to tens of times (solubilization). Simultaneously, the surfactant reduces the gas-liquid interfacial tension, increasing the gas-liquid contact area and thus improving the overall volumetric mass transfer coefficient.

[0041] The specific implementation method is as follows: The system is equipped with an automatic dosing pump, which maintains the Tween 80 concentration in the circulating fluid at 15-65 mg / L (approximately 1-5 times the critical micelle concentration) based on the replacement volume of the circulating fluid and online monitoring data. Tween 80 was chosen because of its low biotoxicity and the fact that it can be slowly degraded by microorganisms without causing cumulative toxicity.

[0042] To maintain the survival of fungi and bacteria in the system, the system also includes a nutrient and dosing device, which includes: Nutrient solution storage tank: for preparing concentrated solutions containing macro-elements (N, P, K) and micro-elements (Fe, Mg, Ca, Zn, Co, Mo, etc.).

[0043] pH adjustment unit: Equipped with storage tanks for acidic solutions (such as H2SO4) and alkaline solutions (such as NaOH).

[0044] Automatic replenishment: The feed is delivered via a precision peristaltic pump according to instructions from the control module.

[0045] To address the control challenges posed by nonlinearity, large time lag, and model uncertainty in biological systems, this invention introduces a control module that automatically adjusts the spraying frequency, nutrient solution dosage, and surfactant concentration based on real-time monitoring of gas concentration, pressure drop, and circulating fluid parameters. This module specifically includes: A sensor array is used for real-time monitoring of gas concentration, pressure drop, and circulating fluid parameters. Gas parameters: Photoionization detector or flame ionization detector monitors the total concentration of volatile organic compounds at the inlet and outlet, respectively; electrochemical sensor monitors H2S and NH3 concentrations; oxygen sensor monitors O2 content.

[0046] Environmental parameters: Differential pressure transmitter monitors the pressure drop of the packing layer; temperature and humidity sensors monitor the air intake status.

[0047] Liquid phase parameters: pH meter, conductivity (EC) meter, and dissolved oxygen (DO) meter are installed in the circulating liquid loop.

[0048] The controller, based on data collected by the sensor array, utilizes a built-in fuzzy inference engine for system control. This invention focuses on designing the following two core control loops: Loop 1: Control of circulating fluid pH and nutrient supply.

[0049] Input variables: =Set value (7.0) - Current measurement value.

[0050] = Rate of change of pH.

[0051] EC = Electrical conductivity (reflects ion concentration / nutrient level).

[0052] Blur: It will be defined as {Negative Large (NB), Negative Small (NS), Zero (ZO), Positive Small (PS), Positive Large (PB)}.

[0053] EC is defined as {Low, Normal, High}.

[0054] Fuzzy rules: Rule 1: If it is NB (severely alkaline), then perform a rapid acid addition operation.

[0055] Rule 2: If the value is ZO (normal) and EC is Low (insufficient nutrition), then perform nutrient supplementation.

[0056] Rule 3: If EC is High (salt accumulation), perform a partial discharge of circulating fluid and replenishment of water.

[0057] Defuzzification: The frequency of the metering pump or the opening degree of the valve is calculated using the centroid method.

[0058] Loop 2: Adaptive control against shock loads.

[0059] Input variables: =Inlet volatile organic compound concentration flow rate (current load).

[0060] RE = (Inlet concentration - Outlet concentration) / Inlet concentration (current removal rate).

[0061] Control logic: Normal mode: When the load is stable and RE>90%, maintain low-frequency spraying (e.g., spray for 5 minutes per hour), and keep the surfactant dosage at the baseline to save energy and reduce consumption.

[0062] Impact mode: When a sharp increase or a significant downward trend in RE is detected: Immediately switch to continuous high-flow spraying to increase the gas-liquid contact area and renew the liquid film on the surface of the biofilm.

[0063] Increase the dosage of Tween80 to a high concentration (e.g., 50-60 mg / L) to maximize its solubilizing ability.

[0064] Increase the supply of nutrient solution to prevent microorganisms from being limited by substrate proliferation but nutrient deficiency.

[0065] By setting this logic, a response can be made before or at the beginning of a load, significantly shortening system recovery time.

[0066] Based on the above-mentioned waste gas treatment system, the specific operating process of the microbial-based waste gas treatment method of the present invention is as follows: S1. Start-up and acclimatization.

[0067] Tiered start-up: Fungal treatment device: Inoculate with fungal spore suspension, control pH to 4.5, spray with nutrient solution containing glucose, keep the packing material moist but not waterlogged. Introduce low-concentration toluene waste gas, gradually increasing the concentration. Visible mycelium will form in approximately 20-30 days.

[0068] Bacterial treatment device: Inoculated with activated sludge, full-volume circulation. No surfactant is added initially. After the biofilm forms (about 10 days), a low concentration of Tween80 (5 mg / L) is added dropwise, and the concentration is doubled every 3 days until the working concentration (20 mg / L) is reached to acclimate the bacteria to the surfactant.

[0069] Overall commissioning: Once the individual removal rates of the treatment units have stabilized, they are connected in series for operation.

[0070] S2, steady-state operation.

[0071] The industrial waste gas to be treated is passed through a heat exchanger or humidification chamber to adjust the temperature to 15-35°C and the relative humidity to over 90%, and to remove particulate matter.

[0072] The pretreated exhaust gas is passed into a fungal filter, with the pH of the filter media controlled at 4.0-5.5 and a residence time of approximately 15-20 seconds. Approximately 60-80% of the hydrophobic volatile organic compounds are removed through direct adsorption and degradation by the aerial mycelia of the fungi.

[0073] The exhaust gas, after being treated by the fungal biofilter, is passed into the bacterial biotrickling filter tower. The pH of the circulating liquid is controlled at 6.5-7.5, and the concentration of polysorbate 80 in the circulating liquid is maintained near the critical micelle concentration, with a residence time of approximately 20-30 seconds. Under the action of the circulating liquid containing Tween 80, the remaining hydrophobic organic compounds, hydrophilic organic compounds, and odorous gases are removed.

[0074] The control module collects data once per second and performs fuzzy inference once per minute to fine-tune the operating parameters.

[0075] S3. Maintenance and troubleshooting.

[0076] Regular salt discharge: Based on the conductivity EC value, a portion of the circulating liquid is automatically discharged (e.g., 5%-10% daily) to prevent the accumulation of salts (sulfates, nitrates) that inhibit microbial activity.

[0077] Dormant protection: During factory shutdowns (such as weekends), the system enters a low-flow circulation mode, intermittently supplementing a small amount of carbon source to maintain minimum microbial activity and ensure rapid recovery upon resumption of production.

[0078] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0079] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A microbial-based waste gas treatment system, characterized in that, It includes a gas pretreatment module, a first-stage fungal biofilter, a second-stage bacterial bio-trickling filter, and a control module; The gas pretreatment module is used to pretreat the industrial waste gas entering the system. It is configured to remove particulate matter from the waste gas and adjust the waste gas temperature to 15-35℃ and the relative humidity to above 90%, thereby providing a suitable microbial growth environment for subsequent biological treatment. The first-stage fungal biofilter is configured as an upflow reactor, filled with hydrophobic composite packing material, inoculated with a degradation community mainly composed of filamentous fungi, and operates under continuous gas phase and intermittent liquid phase spraying conditions. It is used to directly capture and degrade hydrophobic volatile organic compounds in the gas phase through the aerial hyphae of fungi. The second-stage bacterial bio-trickling filter is configured as a counter-current reactor, filled with inert porous packing material, inoculated with a mixed bacterial community mainly composed of bacteria, and equipped with a circulating nutrient solution spraying system containing a surfactant dosing device. This system uses surfactant solubilization and bacterial bio-oxidation to remove residual hydrophobic volatile organic compounds, hydrophilic volatile organic compounds, and malodorous gases. The control module is used to automatically adjust the spraying frequency, nutrient solution dosage and surfactant concentration based on real-time monitored gas concentration, pressure drop and circulating liquid parameters. This includes: a sensor array collecting gas concentration, pressure drop and circulating liquid parameters, and a controller using a built-in fuzzy inference engine to control the system based on the data collected by the sensor array.

2. The microbial-based waste gas treatment system according to claim 1, characterized in that, The hydrophobic composite filler is made by mixing and curing the following raw materials in volume percentages: 30%-40% compost or humus, 20%-30% perlite or vermiculite, 10%-15% cement or sodium silicate binder, 15%-25% biochar or hydrophobically modified zeolite, and 1%-5% calcium carbonate buffer. The preparation process of the filler includes adding aluminum powder foaming agent to the mixed raw materials so that the cured filler has a multi-level pore structure, wherein the porosity is greater than 60% and the specific surface area is greater than 400m² / m. The surface of the filler has hydrophobic properties and a slightly acidic environment suitable for the attachment and growth of fungal aerial hyphae.

3. The waste gas treatment system based on microorganisms according to claim 1, characterized in that, The filamentous fungal community inoculated in the first-stage fungal biofilter is composed of the following parts by weight: 30-50 parts of Fusarium solanum, 20-40 parts of Hydnocarpus syringae, and 10-30 parts of Exophytum oxysporum. The microbial community was obtained by domestication in an acidic culture medium containing a hydrophobic carbon source, enabling it to produce a large number of aerial mycelia in an environment with a relative humidity of 40%-60%.

4. The microbial-based waste gas treatment system according to claim 1, characterized in that, The second-stage bacterial bio-trickling filter tower is filled with inert porous packing material, which is selected from one or more combinations of polyurethane foam cubes, polypropylene multifaceted hollow spheres or volcanic rock, and has a specific surface area of ​​more than 500 m / m and a porosity of more than 90%. The mixed bacterial flora inoculated in the second-stage bacterial bio-trickling filter includes: *Pseudomonas putida*, used to degrade benzene compounds; *Thiobacillus denitrificationus*, used to oxidize hydrogen sulfide; and *Rhodococcus*, used to assist in the adsorption and degradation of hydrophobic alkanes. The trickling filter is configured for gas-liquid countercurrent operation, with the pH value of the circulating spray liquid controlled at 6.5-7.5 and the liquid spray density controlled at 2-10 m / mh.

5. The microbial-based waste gas treatment system according to claim 1, characterized in that, The surfactant dosing device is used to add a nonionic surfactant, preferably polysorbate 80, to the circulating nutrient solution of the second-stage bacterial bio-trickling filter tower; and the control system is configured to maintain the concentration of the surfactant in the circulating solution between 15 mg / L and 65 mg / L, that is, near the critical micelle concentration of the surfactant, so as to promote the transfer of hydrophobic pollutants from the gas phase to the liquid phase biofilm by utilizing the micelle solubilization effect.

6. The microbial-based waste gas treatment system according to claim 1, characterized in that, The control module includes an anti-impact load adaptive control logic, specifically: when the rate of change of the inlet exhaust gas load exceeds a preset threshold, it automatically switches to impact mode, controls the circulation pump to increase the spray flow rate, and controls the dosing pump to increase the dosage of surfactant and nutrient solution until the outlet removal rate returns to the steady-state target value.

7. A microbial-based waste gas treatment method, characterized in that, Includes the following steps: The industrial waste gas to be treated is passed through a heat exchanger or humidification chamber to adjust the temperature to 15-35°C and the relative humidity to above 90%, and to remove particulate matter. The pretreated waste gas is passed into the first-stage fungal biological filter, and the pH of the packing layer is controlled at 4.0-5.

5. The aerial mycelium of fungi directly adsorbs and degrades the hydrophobic volatile organic compounds in the waste gas. The exhaust gas treated by the first-stage fungal biofilter is passed into the second-stage bacterial bio-trickling filter tower. The pH of the circulating liquid is controlled at 6.5-7.5, and the concentration of polysorbate 80 in the circulating liquid is maintained near the critical micelle concentration. The remaining hydrophobic organic compounds, hydrophilic organic compounds and malodorous gases are removed by the solubilization of surfactants and the biological oxidation of bacteria. The controller in the control module monitors the system pressure drop, pH value, and organic compound removal rate in real time; when the pressure drop is too high, backwashing or biomass reduction strategies are executed; when the pH deviates, acid or alkali is added automatically; and when there is a load shock, spraying and solubilization are automatically enhanced.

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