Microbial composite material and preparation method and application thereof

Abstract

The present application relates to a kind of microbial composite material and its preparation method and application, belong to composite material technical field.The microbial composite material provided by the present application includes the following preparation raw materials: microorganism and carrier material;The microorganism is the microorganism of degradable pollutant;The specific surface area of the carrier material is 2~200m 2 / g;The porosity of the carrier material is 30~95%.The microbial composite material of the present application mainly utilizes the metabolic capacity of microorganism to degrade pollutants, and the carrier material used has a certain specific surface area and porosity, which can provide a suitable growth environment and medium for microorganisms, while expanding the contact area of pollutant-containing gas and microorganisms, adsorbing and concentrating pollutant-containing gas to supply microorganisms for degradation, achieving the effect of air purification, forming a composite material with good mechanical properties, not easy to collapse and good purification effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite materials, in particular to a microbial composite material and a preparation method and application thereof. BACKGROUND

[0002] There are pollutants in the form of gas in the atmospheric environment, and how to remove this part of pollutants is an important problem to be solved at present. For example, volatile organic compounds (VOCs) are one of the main pollutants in the atmosphere, and controlling the content of VOCs in the atmosphere is of great significance to achieve pollution reduction and carbon reduction synergies and promote the sustainable improvement of ecological environment quality. Existing VOCs removal technologies include physical adsorption of activated carbon and other materials, chemical adsorption of chemical reagents, and catalytic degradation of noble metals or metal oxides. However, these methods have some disadvantages, such as: physical adsorption of activated carbon and other materials has the problem of adsorption saturation leading to reduced efficiency, adsorption performance decreases in high temperature and high humidity environment, and needs to be replaced or regenerated after adsorption saturation, otherwise it will cause secondary pollution; chemical adsorption also has performance decline with the consumption of chemical reagents until no adsorption capacity, which needs to be replaced; the cost of catalytic degradation of VOCs by noble metal is high, and certain reaction conditions are required, and different catalysts have different catalytic effects on different types of VOCs, and the catalytic degradation effect is not ideal for some difficult-to-treat VOCs. In addition, the service life of the catalyst is affected by factors such as reaction conditions, VOCs composition and reactant concentration, and has a limited service life.

[0003] Therefore, it is necessary to find a material or method that can simply and effectively remove VOCs. SUMMARY

[0004] In order to overcome the problems existing in the prior art, one of the purposes of the present application is to provide a microbial composite material, which can efficiently degrade pollutants such as VOCs to obtain purified gas, and the preparation process of the composite material is simple and has a long service life.

[0005] The second purpose of the present application is to provide a preparation method of the above-mentioned microbial composite material.

[0006] The third purpose of the present application is to provide a microbial filter screen comprising the above-mentioned microbial composite material.

[0007] The fourth purpose of the present application is to provide a gas purification assembly comprising the above-mentioned microbial filter screen.

[0008] The fifth purpose of the present application is to provide a purification method for VOCs-containing gas.

[0009] In order to achieve the above-mentioned purposes, the technical solution adopted by the present application is:

[0010] The first aspect of the present application provides a microbial composite material, comprising the following raw materials: microorganisms and carrier materials; the microorganisms are microorganisms capable of degrading pollutants; the specific surface area of the carrier materials is 2-200 m 2 / g; and the porosity of the carrier materials is 30-95%.

[0011] The microbial composite material provided by the first aspect of the present application has at least the following beneficial effects:

[0012] The microbial composite material of the present application mainly utilizes the metabolic capacity of microorganisms to degrade pollutants, and the carrier materials used have a certain specific surface area and porosity, which can provide a suitable growth environment and medium for microorganisms, and at the same time, can expand the contact area of the gas containing pollutants and the microorganisms, adsorb and concentrate the gas containing pollutants to supply the microorganisms for degradation, achieve the effect of purifying the gas, and form a composite material with good mechanical properties, which is not easy to collapse and has good purification effect. The microbial composite material of the present application has good mechanical stability, long service life, good effect of degrading pollutants, and high purification efficiency.

[0013] In some embodiments of the present application, the carrier materials include at least one of porous carbon materials, mineral materials or organic materials.

[0014] The porous carbon materials, mineral materials or organic materials as carrier materials can provide nutrients for the growth and reproduction of microorganisms, thereby maintaining the amount of microorganisms contained in the composite material, realizing the recycling of the composite material, maintaining the stability of the purification effect, having long service life and low purification cost. Since the carrier materials can be consumed and utilized by microorganisms, the composite material will not cause secondary pollution after use, and is harmless to the environment and human health, and is green and environmentally friendly.

[0015] In some embodiments of the present application, the carrier materials include at least one of activated carbon, activated carbon fiber, carbon molecular sieve, expanded graphite, porous graphite, carbon nanotube, carbon aerogel, crushed stone, volcanic rock, zeolite, ceramic ball, sawdust, bark, hay, peat, sponge, diatomite, polyethylene fiber or polyurethane.

[0016] In some embodiments of the present application, the microorganisms are obtained by domesticating and screening the microorganisms according to the types of pollutants to be degraded.

[0017] In some embodiments of the present application, the microbial load is calculated based on the total protein content of the microorganisms, and the microbial load is 8-50 mg / g per g of carrier materials.

[0018] With a proper microbial loading, the microbial composite material can not collapse and has good mechanical stability, and can also have good degradation and purification effect.

[0019] In some embodiments of the present application, the microbial composite material has a granular shape, and the particle size of the microbial composite material is 0.5-5 mm.

[0020] The granular composite material has good processing performance, filling performance and stability.

[0021] The second aspect of the present application provides a preparation method of the microbial composite material of the first aspect of the present application, comprising the following steps: mixing and forming the microorganism and the carrier material to obtain the microbial composite material.

[0022] The preparation method of the microbial composite material provided by the second aspect of the present application has at least the following beneficial effects:

[0023] The preparation method of the microbial composite material of the present application has simple process, low equipment requirement and low preparation cost.

[0024] The microorganism and the carrier material are fully mixed to uniformly load the microorganism on the carrier material, and then formed to form the composite material.

[0025] The third aspect of the present application provides a microbial filter screen, comprising a fixing structure and a filtering structure, the filtering structure is arranged in the fixing structure; the filtering structure contains the microbial composite material of the first aspect of the present application.

[0026] The microbial filter screen provided by the third aspect of the present application has at least the following beneficial effects:

[0027] The microbial filter screen of the present application has simple structure, good formability of the filtering structure, low running cost, long service life, low wind resistance, high degradation and purification efficiency, good degradation stability, and is suitable for treating various types of pollutant-containing gas, especially suitable for treating various VOCs-containing gas, including low-concentration organic waste gas and high-concentration volatile organic compounds.

[0028] In some embodiments of the present application, the fixing structure is a double-layer fixing layer, and the filtering structure is arranged between the fixing layers to form a filtering layer.

[0029] In some embodiments of the present application, the fixing layer comprises a planar structure, a continuous bending structure or a combination thereof.

[0030] The plane structure has simple processing technology, and the continuous bending structure can reduce wind resistance compared with the plane structure, and can be selected according to actual needs.

[0031] In some embodiments of the present application, the thickness of the filter layer is 0.1-2 mm.

[0032] In some embodiments of the present application, the fixing structure comprises a fixing outer frame and a plurality of honeycomb grids, the honeycomb grids are arranged inside the fixing outer frame, and the filter structure is arranged inside the honeycomb grids.

[0033] The filter structure in the above structure can be arranged according to actual needs, if it is arranged densely, the wind resistance of the filter screen is large, if it is arranged sparsely, the wind resistance of the filter screen is small.

[0034] The fourth aspect of the present application provides a gas purification assembly comprising the microbial composite material of the first aspect of the present application or the microbial filter screen of the third aspect of the present application.

[0035] The gas purification assembly provided by the fourth aspect of the present application has at least the following beneficial effects:

[0036] The gas purification assembly of the present application has the advantages of low operating cost, long service life, high degradation and purification efficiency, and good degradation stability, and can effectively degrade pollutants in the gas, especially VOCs, to obtain purified gas.

[0037] The fifth aspect of the present application provides a purification method of VOCs-containing gas, which is realized by using the gas purification assembly of the fourth aspect of the present application.

[0038] The purification method of VOCs-containing gas provided by the fifth aspect of the present application has at least the following beneficial effects:

[0039] The purification method of the present application can effectively degrade various types of VOCs, and realize effective purification of VOCs-containing gas.

[0040] In some embodiments of the present application, the purification method comprises the following steps: making the VOCs-containing gas pass through the gas purification assembly, and the included angle between the flow direction of the VOCs-containing gas and the plane in which the microbial filter screen in the air purification assembly is located is greater than 0°.

[0041] Making the VOCs-containing gas pass through the microbial filter screen at a certain angle can realize sufficient contact between VOCs and microbial fillers, and effectively degrade VOCs.

[0042] In some embodiments of the present application, the angle between the direction of the gas flow containing VOCs and the plane in which the microorganism filter screen in the air purification assembly is located is 30-90°.

[0043] In some embodiments of the present application, the VOCs include at least one of alkanes, alkenes, alkynes, arenes, halogenated hydrocarbons, alcohols, aldehydes, ethers, ketones, acids or esters.

[0044] The method of the present application is suitable for removal of various types of VOCs, and the microorganisms obtained by domestication and screening according to the types of VOCs in the gas to be purified can be used in the present application to achieve effective removal of VOCs. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 Structure diagram of the microorganism filter screen (A) and the direction of the gas flow (B) in some embodiments of the present application.

[0046] Figure 2 Structure diagram of the microorganism filter screen (A) and the direction of the gas flow (B) in some embodiments of the present application.

[0047] Figure 3 Structure diagram of the microorganism filter screen (A) and the direction of the gas flow (B) in some embodiments of the present application.

[0048] Figure 4 Structure diagram of the microorganism filter screen (A) and the direction of the gas flow (B) in some embodiments of the present application. -1 Average purification rate of acetic acid per day in Example 4 of the present application. DETAILED DESCRIPTION

[0049] The present application will be further described in detail by specific examples. It should be understood that the following examples are only used to further illustrate the present application, and cannot be understood as a limitation on the scope of protection of the present application. Some non-essential improvements and adjustments made by those skilled in the art according to the principles set forth in the present application are within the scope of protection of the present application. The following examples are only one example in the appropriate range, i.e. those skilled in the art can make appropriate selection within the scope of the present application, and are not limited to the specific data in the following examples. The raw materials, reagents or devices used in the following examples and comparative examples are commercially available or can be obtained by known methods unless otherwise specified.

[0050] The first aspect of the embodiment of the present application provides a microorganism composite material comprising the following raw materials: microorganisms and carrier materials; the microorganisms are microorganisms capable of degrading pollutants; the specific surface area of the carrier materials is 2-200 m 2 / g; the porosity of the carrier material is 30-95%.

[0051] The microbial composite material in the embodiments of the present application mainly utilizes the metabolic capacity of the microorganisms to degrade pollutants, and the carrier material used has a certain specific surface area and porosity, which can provide a suitable growth environment and medium for the microorganisms, and at the same time, can expand the contact area of the gas containing pollutants and the microorganisms, adsorb and concentrate the gas containing pollutants to supply the microorganisms for degradation, achieve the effect of purifying the gas, and form a composite material which has good mechanical properties, is not easy to collapse, and has good purification effect. The microbial composite material of the present application has good mechanical stability, long service life, good effect of degrading pollutants, and high purification efficiency.

[0052] In some embodiments of the present application, the specific surface area of the carrier material is 5-180 m 2 / g; in some specific embodiments of the present application, the specific surface area of the carrier material is 7-110 m 2 / g; in some examples of the present application, the specific surface area of the carrier material is 9-60 m 2 / g; non-limiting specific examples are 10 m 2 / g, 15 m 2 / g, 20 m 2 / g, 30 m 2 / g, 40 m 2 / g, or 50 m 2 / g.

[0053] In some embodiments of the present application, the porosity of the carrier material is 35-90%; in some specific embodiments of the present application, the porosity of the carrier material is 38-85%; in some examples of the present application, the porosity of the carrier material is 40-80%; non-limiting specific examples are 45%, 50%, 55%, 60%, 65%, 70%, or 75%.

[0054] In some embodiments of the present application, the carrier material includes at least one of a porous carbon material, a mineral material, or an organic material.

[0055] The carrier material used in the embodiments of the present application can provide nutrients for the growth and reproduction of microorganisms, thereby maintaining the amount of microorganisms contained in the composite material, realizing the recycling of the composite material, maintaining the stability of the purification effect, having a long service life and low purification cost, and since the carrier material can be consumed and utilized by the microorganisms, the composite material will not cause secondary pollution after use, is harmless to the environment and human health, and is green and environmentally friendly.

[0056] The porous carbon material has a porous structure, which can provide growth space for the microorganism and promote the growth of the microorganism, and can also provide a carbon source for the microorganism, further promoting the growth and reproduction of the microorganism. Non-limiting examples of the porous carbon material include activated carbon, activated carbon fiber, carbon molecular sieve, expanded graphite, porous graphite, carbon nanotube, or carbon aerogel.

[0057] The mineral material can provide growth space for the microorganism, and in particular, contains a large amount of mineral elements, which can also be used as nutrients for the microorganism. Non-limiting examples of the mineral material include crushed stone, volcanic rock, zeolite, or ceramic ball.

[0058] The organic material includes natural organic material and synthetic organic material, which is a kind of macromolecule formed by one or more molecules or molecular groups combined by covalent bond to have multiple repeating monomer units. The organic material can provide a carbon source for the microorganism for the growth of the microorganism. The natural organic material includes wood material, fiber, protein, and natural rubber, etc. The synthetic material includes synthetic rubber, synthetic resin, synthetic fiber, etc. Non-limiting examples of the organic material include sawdust, bark, hay, peat, sponge, diatomite, polyethylene fiber, or polyurethane, etc.

[0059] In some embodiments of the present application, the carrier material includes at least one of activated carbon, activated carbon fiber, carbon molecular sieve, expanded graphite, porous graphite, carbon nanotube, carbon aerogel, crushed stone, volcanic rock, zeolite, ceramic ball, sawdust, bark, hay, peat, sponge, diatomite, polyethylene fiber, or polyurethane. In some specific embodiments of the present application, the carrier material includes at least one of activated carbon, crushed stone, volcanic rock, zeolite, ceramic ball, sawdust, bark, hay, peat, sponge, diatomite, polyethylene fiber, or polyurethane.

[0060] In some examples of the present application, the carrier material is selected from ceramic ball, and further, the porosity of the ceramic ball is 31-55%.

[0061] In some examples of the present application, the carrier material is selected from sawdust, bark, and other wood material, and further, the porosity of the wood material is 50-75%, and further, the specific surface area of the wood material is 2-43 m 2 / g.

[0062] In some examples of the present application, the carrier material is a mixture of ceramic ball and activated carbon.

[0063] The microorganism in the present application is selected according to actual needs.

[0064] In some embodiments of the present application, the microorganism is obtained by domesticating and screening the microorganism according to the type of pollutants to be degraded.

[0065] In some embodiments of the present application, the microorganism is obtained by a method comprising the following steps: domesticating and screening the microorganism extract containing pollutants to obtain the microorganism. The microorganism extract contains mixed microorganisms, which can be extracted from sludge, sewage, etc. In some examples of the present application, the pollutants are VOCs, and the microorganism is obtained by a method comprising the following steps: domesticating and screening the microorganism extract containing VOCs to obtain the microorganism.

[0066] In some embodiments of the present application, the microorganism loading is calculated based on the total protein content of the microorganism, and the microorganism loading is 8-50 mg·g -1 ; in some embodiments of the present application, the microorganism loading is 15-45 mg·g -1 ; in some embodiments of the present application, the microorganism loading is 25-40 mg·g -1 ; non-limiting specific examples are 28 mg·g -1 , 30 mg·g -1 , 32 mg·g -1 , 35 mg·g -1 or 38 mg·g -1 .

[0067] The microorganism and the carrier material of the present application are mixed at a suitable ratio to obtain a microorganism composite material with better pollutant degradation effect and smaller wind resistance. If the microorganism is too much, it will cause less filler to affect molding, and the medium for microorganism reproduction is too little to affect the contact area of the microorganism with the pollutant-containing gas, thereby affecting the purification effect; if the microorganism is too little, it will affect the purification efficiency.

[0068] In some embodiments of the present application, the shape of the microorganism composite material is granular, and the particle size of the microorganism composite material is 0.5-5 mm; in some embodiments of the present application, the particle size of the microorganism composite material is 1-3 mm; non-limiting specific examples are 1.5 mm, 2 mm or 2.5 mm. The use of granular composite material has good processing performance, filling performance and stability.

[0069] The second aspect of the embodiments of the present application provides a preparation method of the microorganism composite material of the first aspect of the present application, comprising the following steps: mixing and molding the microorganism and the carrier material to obtain the microorganism composite material.

[0070] The preparation method of the microorganism composite material in the embodiments of the present application is simple in process, low in equipment requirement and low in preparation cost.

[0071] The microorganism and the carrier material are mixed sufficiently to allow the microorganism to be uniformly loaded on the carrier material, and then molded to form the composite material.

[0072] In some embodiments of the present application, the method of forming includes at least one of a granulation process, an extrusion process, an injection process, or a compression process; in some specific embodiments of the present application, the method of forming is selected from a granulation process.

[0073] In some embodiments of the present application, the granulation process includes at least one of a general granulation method, a spray granulation method, or a briquetting granulation method; in some specific embodiments of the present application, the granulation process is selected from a general granulation method.

[0074] The general granulation method refers to mixing the preparation raw materials and then performing granulation on a dedicated granulator, such as a cylinder granulator and a disc granulator. The spray granulation method refers to mixing the preparation raw materials to form a slurry, and then spraying the slurry into a granulation tower through a sprayer for atomization and drying to obtain spherical granules with good flowability. The briquetting granulation method refers to pre-pressing the preparation raw materials with a binder into briquettes at a low pressure, and then crushing and sieving the briquettes to form granules with a large bulk density.

[0075] The third aspect of the embodiments of the present application provides a microbial filter screen, which includes a fixing structure and a filtering structure, and the filtering structure is arranged inside the fixing structure; the filtering structure contains the microbial composite material of the first aspect of the present application.

[0076] The microbial filter screen in the embodiments of the present application has a simple structure, the filtering structure has good formability and is not easy to collapse, the filter screen has low operating cost, long service life, low wind resistance, high degradation and purification efficiency, and good degradation stability, and is suitable for treating various types of pollutants, and is especially suitable for treating various VOCs, including low-concentration organic waste gas and high-concentration volatile organic compounds.

[0077] In the microbial filter screen in the embodiments of the present application, the fixing structure is used to fix the filtering structure to avoid the collapse of the filtering structure, and the fixing structure used will affect the wind resistance but will not affect the degradation effect, and the material and thickness of the fixing structure can be adjusted according to the actual application requirements.

[0078] In some embodiments of the present application, the material of the fixing structure is a fiber textile material.

[0079] In some embodiments of the present application, the fixing structure is a double-layer fixing layer, and the filtering structure is arranged between the fixing layers to form a filtering layer.

[0080] In some embodiments of the present application, the fixing layer includes a planar structure, a continuous bending structure, or a combination thereof.

[0081] Figure 1The diagram shows the structure (A) and airflow direction (B) of a microbial filter in some embodiments of the present invention, where 1 represents the filter layer, 2 represents the fixing layer, and surface A represents the plane where the filter is located. The structural diagrams of the microbial filter in some embodiments of the present invention are as follows: Figure 1 As shown in (A), the filter includes a filter layer 1 and two fixing layers 2 on both sides, with the fixing layers 2 having a planar structure. The layers are bonded together with an adhesive. The function of the fixing layers 2 is to fix the microbial composite material and prevent the filter layer containing the microbial composite material from collapsing.

[0082] Figure 2 The diagram shows the structure (A) and airflow direction (B) of a microbial filter in other embodiments of the present invention, where 1 represents the filter layer, 2 represents the fixing layer, and surface A represents the plane where the filter is located. The diagram shows the structure of the microbial filter in other embodiments of the present invention as follows: Figure 2 As shown in (A), the structure includes a filter layer 1 and two fixing layers 2 on both sides, with the fixing layers 2 having a continuously bent structure. The layers are bonded together with an adhesive. The fixing layers 2 also serve to fix the microbial composite material, preventing the filter layer containing the microbial composite material from collapsing. Furthermore, the continuous bending structure reduces wind resistance.

[0083] In some embodiments of the present invention, the thickness of the filter layer is 0.1 to 2 mm; in some specific embodiments of the present invention, the thickness of the filter layer is 0.2 to 1.5 mm; in some examples of the present invention, the thickness of the filter layer is 0.3 to 1 mm; non-limiting specific examples include 0.5 mm, 0.7 mm or 0.9 mm.

[0084] In some embodiments of the present invention, the fixing structure includes a fixing frame and a plurality of honeycomb grids, the honeycomb grids being disposed inside the fixing frame; the filtering structure is disposed inside the honeycomb grids.

[0085] Figure 3 The diagram shows the structure (A) and airflow direction (B) of the microbial filter in other embodiments of the present invention, where 1 represents the fixed outer frame, 2 represents the honeycomb mesh, 3 represents the filter structure, and surface A represents the plane where the filter is located. The diagram shows the structure of the microbial filter in other embodiments of the present invention as follows: Figure 3 As shown in (A), the structure includes a fixed outer frame 1, several honeycomb grids 2, and a filter structure 3. The filter structure 3 is granular and adheres to the wall of the honeycomb grids 2. The granular filter structure in this structure can be filled according to actual needs. If the filling is very dense, the air resistance of the filter is high; if the filling is sparse, the air resistance of the filter is low.

[0086] A fourth aspect of the present invention provides a gas purification assembly, including a microbial filter from the third aspect of the present invention.

[0087] The gas purification assembly in the embodiment of the present application has the advantages of low operation cost, long service life, high degradation and purification efficiency, and good degradation stability, and can effectively degrade the pollutants in the gas, especially VOCs, to obtain purified gas.

[0088] In some embodiments of the present application, the gas purification assembly comprises one or more microbial filter screens. The number of the microbial filter screens is two or more.

[0089] In some embodiments of the present application, when the gas purification assembly comprises a plurality of microbial filter screens, the combination form between the microbial filter screens is planar joint or stacking. If the planar joint combination form is adopted, the degradation efficiency of the gas purification assembly is increased, the wind resistance is unchanged, but the actual required space volume is relatively large; if the stacking combination form is adopted, the degradation efficiency of the gas purification assembly is increased, the actual required space volume is relatively small, but the wind resistance is increased. The specific design needs to be made according to the actual needs.

[0090] The fifth aspect of the embodiment of the present application provides a purification method of VOCs-containing gas, which is realized by using the gas purification assembly of the fourth aspect of the present application.

[0091] The purification method in the embodiment of the present application can effectively degrade various types of VOCs, and realize the effective purification of VOCs-containing gas.

[0092] In some embodiments of the present application, the purification method comprises the following steps: making the VOCs-containing gas pass through the gas purification assembly, and the included angle between the gas flow direction of the VOCs-containing gas and the plane where the microbial filter screen in the gas purification assembly is located is greater than 0°.

[0093] Making the VOCs-containing gas pass through the microbial filter screen at a certain included angle can realize the sufficient contact between the VOCs and the microbial filler, and effectively degrade the VOCs.

[0094] In some embodiments of the present application, the included angle between the gas flow direction of the VOCs-containing gas and the plane where the microbial filter screen in the gas purification assembly is located is 30-90°; in some specific embodiments of the present application, the included angle between the gas flow direction of the VOCs-containing gas and the plane where the microbial filter screen in the gas purification assembly is located is 60-90°; in some specific embodiments of the present application, the included angle between the gas flow direction of the VOCs-containing gas and the plane where the microbial filter screen in the gas purification assembly is located is 80-90°; non-limiting specific examples are 82°, 85° or 90°. The VOCs-containing gas passes through the microbial filter screen in the vertical or nearly vertical direction, which is beneficial to reduce the wind resistance.

[0095] In some embodiments of the present application, when the microbial filter screen in the structure shown in formula (A) is adopted, the gas flow direction is as shown in formula (B). Figure 1 Figure 1 ​(B) shows that the airflow direction is perpendicular to the plane of the filter screen, and the angle between the airflow direction and the plane of the filter screen is 90°, the plane of the filter screen is the central plane of the filter screen, as shown in Figure 2 (B) shows the plane A.

[0096] In some embodiments of the present application, when the microbial filter screen with the structure shown in Figure 2 (A) is used, the airflow direction is as shown in Figure 2 (B), that is, the airflow direction is perpendicular to the plane of the filter screen, and the angle between the airflow direction and the plane of the filter screen is 90°, the plane of the filter screen is the central plane of the filter screen, as shown in Figure 2 (B) shows the plane A.

[0097] In some embodiments of the present application, when the microbial filter screen with the structure shown in Figure 3 (A) is used, the airflow direction is as shown in Figure 3 (B), that is, the airflow direction is perpendicular to the plane of the filter screen, and the angle between the airflow direction and the plane of the filter screen is 90°, the plane of the filter screen is the central plane of the filter screen, as shown in Figure 3 (A), that is Figure 3 (B) shows the plane A.

[0098] In some embodiments of the present application, the VOCs include at least one of alkanes, alkenes, alkynes, arenes, halogenated hydrocarbons, alcohols, aldehydes, ethers, ketones, acids or esters; in some specific embodiments of the present application, the VOCs include at least one of methane, ethane, ethylene, acetylene, benzene, toluene, xylene, styrene, trichloroethylene, trichloromethane, trichloroethane, chloroethylene, chlorobenzene, ethanol, formaldehyde, diethyl ether, acetone, acetic acid, diisocyanate or diisocyanatetoluene; in some examples of the present application, the VOCs include at least one of benzene, toluene, xylene, styrene, ethanol, formaldehyde, diethyl ether, acetone or acetic acid; in some specific examples of the present application, the VOCs are selected from toluene or acetic acid.

[0099] The method in the embodiments of the present application is suitable for the removal of various types of VOCs, and the microorganisms are domesticated and screened according to the types of VOCs in the gas to be purified, and the obtained microorganisms are applied in the present application to achieve effective removal of VOCs.

[0100] In some embodiments of the present application, the types of microorganisms need to be domesticated and screened according to the types of VOCs in the gas to be purified. In some specific embodiments of the present application, the specific process of domestication and screening is to use a gas containing a specific type of VOCs to domesticate the sludge extract to obtain microorganisms that can purify the specific type of VOCs. After a long period of domestication, the obtained microorganisms are a mixed microbial population, which has good degradation effect on the specific type of VOCs, and the microorganisms are used to treat the specific VOCs, and the degradation and purification effect is good.

[0101] The following is further illustrated in conjunction with specific examples.

[0102] Example 1

[0103] A microbial composite material, the raw materials for preparation including microorganisms and carriers, wherein the carrier material is a mixture of ceramsite and activated carbon, forming a carrier material with different specific surface areas, and the specific surface areas are shown in Table 1, and the microbial loading is 27-28 mg·g -1 The microorganisms are a mixed microbial population extracted from sludge and then subjected to long-term acclimation treatment of acetic acid.

[0104] The specific preparation process of the microbial composite material is as follows: the carrier material and the microorganisms are thoroughly mixed to uniformly disperse and load the microorganisms on the carrier material, and then a granulator is used for granulation to obtain the microbial composite material.

[0105] Application Example 1

[0106] A microbial filter screen, the structure of which is as shown in Figure 1 (A), wherein the filter layer 1 is filled with the microbial composite material of Example 1, and the thickness is 0.5 mm; the fixed layer 2 is a fiber textile material; and the size of the filter screen is 10 mm x 10 mm.

[0107] The acetic acid gas is passed through the microbial filter screen in this example in the manner of Figure 1 (B), and the average degradation rate and the wind resistance of acetic acid are measured, which is measured according to GB / T18801-2022, and the results are shown in Table 1.

[0108] Table 1 Acetic acid degradation effect and wind resistance under different specific surface area carrier materials

[0109]

[0110]

[0111] As can be seen from Table 1, with the increase of the specific surface area, the average degradation rate of the filter screen to the pollutants first increases and then decreases, and the reason for the decrease of the average degradation rate is that the larger specific surface area will cause the microorganisms to grow excessively and form a dense biofilm on the surface of the filler, resulting in an increase in the wind resistance of the filter screen and a decrease in the average degradation rate.

[0112] Application Example 2

[0113] A microbial filter screen, the structure of which is as shown in Figure 2 (A), wherein the filter layer 1 is filled with the microbial composite material of Example 1, and the thickness is 0.5 mm; the fixed layer 2 is a fiber textile material; and the size of the filter screen is 10 mm x 10 mm.

[0114] Acetic acid gas as Figure 2 (B) The average degradation rate and air resistance of acetic acid were measured using the microbial filter in this example, according to GB / T18801-2022. Compared with Application Example 1, under the same microbial load, the average degradation rate of acetic acid in this example is basically the same as that in Application Example 1, while the air resistance is reduced.

[0115] Example 2

[0116] A microbial composite material is obtained by mixing and granulating a carrier material and microorganisms. The carrier material is a mixture of ceramsite and activated carbon to form carrier materials with different porosities. The content of microorganisms in carrier materials with different porosities was measured at the initial stage (when just loaded) and after 5 days to determine their growth. The details are shown in Table 2.

[0117] The specific preparation process of the microbial composite material is as follows: the carrier material and microorganisms are thoroughly mixed so that the microorganisms are uniformly dispersed and loaded on the carrier material, and then granulated using a granulator to obtain the microbial composite material.

[0118] Table 2 Microbial growth under carrier materials with different porosities

[0119]

[0120]

[0121] As shown in Table 2, microorganisms need sufficient space to grow and reproduce, so the porosity should not be too low to avoid restricting the activity of microorganisms. At the same time, the porosity should not be too high either, otherwise it will sacrifice the mechanical stability of the packing, making the packing easy to break and collapse, and will also affect the lifespan of microorganisms, thus affecting the lifespan of the filter screen. A porosity of 30% to 95% is preferred.

[0122] Example 3

[0123] A microbial composite material is obtained by mixing and granulating a carrier material and microorganisms. The carrier material is a wood-based material with a porosity of 50-75% and a specific surface area of ​​2-43 m². 2 / g, the microbial load is shown in Table 3. The microorganisms are a mixed microbial population extracted from sludge and then subjected to long-term domestication treatment with toluene.

[0124] The specific preparation process of the microbial composite material is as follows: the carrier material and microorganisms are thoroughly mixed so that the microorganisms are uniformly dispersed and loaded on the carrier material, and then granulated using a granulator to obtain the microbial composite material.

[0125] Application Example 3

[0126] A microbial filter, as shown in Figure 1 (A), wherein the filter layer 1 is filled with the microbial composite material of Example 3, with a thickness of 0.5 mm; the fixed layer 2 is a fiber textile material; the size of the filter is 10 mm x 10 mm.

[0127] Toluene gas is passed through the microbial filter in this example in the manner of Figure 1 (B), and the average degradation rate of toluene and the wind resistance are measured, which are measured according to GB / T18801-2022, and the results are shown in Table 3.

[0128] Table 3 Toluene degradation effect and wind resistance under different microbial loadings

[0129] Microbial load (protein / carrier material) / mg g -1 ]] Average degradation rate of toluene / mg · (m 3 ·d) -1 ]]> Wind resistance / Pa 7.62 4.12 13 15.51 4.98 46 26.37 6.65 75 40.53 6.32 145 48.75 5.90 226 55.57 5.41 309

[0130] As can be seen from Table 3, with appropriate microbial loading, the toluene degradation effect is higher. If the microbial loading is too small, the degradation rate is low; if the microbial loading is too large, a microbial film is easily formed, which causes the wind resistance of the filter to increase and the average degradation rate to decrease.

[0131] Example 4

[0132] A microbial composite material is obtained by mixing and granulating a carrier material and microorganisms, wherein the carrier material is ceramsite, with a porosity of 44.12%, a specific surface area of 2.4 m 2 / g, and a particle diameter of 1-3 mm, and the microbial loading is shown in Table 4. The microorganisms are a mixed microbial population extracted from sludge, which is then treated by long-term acclimation of acetic acid to obtain a mixed microbial population.

[0133] The specific preparation process of the microbial composite material is as follows: the carrier material and the microorganisms are thoroughly mixed to uniformly disperse the microorganisms on the carrier material, and then a granulator is used to granulate to obtain the microbial composite material.

[0134] Application Example 4

[0135] A microbial filter, as shown in Figure 3 (A), includes a fixed outer frame 1, a plurality of honeycomb grids 2, and a filter structure 3, and the filter structure 3 is a granular microbial composite material adhered to the walls of the honeycomb grid 2. The size of the filter is 10 mm x 10 mm, and the filling amount of the microbial composite material in the filter is 100 g.

[0136] Acetic acid gas is passed through the microbial filter in this example in the manner of Figure 3 (B), and the average degradation rate of acetic acid is measured, which is measured according to GB / T18801-2022, and the results are shown in Table 4.

[0137] Table 4 acetic acid degradation effect under different microbial load

[0138] Microbial load (protein / carrier material) / mg g -1 ]] Average degradation rate of acetic acid / mg · (m 3 ·d) -1 ]]> 5.3 2.23 27.1 6.70 48.5 9.44 54.3 -

[0139] In Table 4, when the microbial load is greater than 50 mg·g -1 , the ceramsite filler cannot be successfully formed and is prone to collapse.

[0140] In this example, when the microbial load is 27.1 mg·g -1 , the average acetic acid degradation rate changes with days as shown in Table 4. Figure 4 It can be seen that the average acetic acid degradation rate is basically stable when the microbial filter screen is used to purify acetic acid, and has a long service life.

[0141] The microbial composite material in the embodiment of the present application mainly uses the metabolic capacity of microorganisms to degrade pollutants, and the carrier material used has a certain specific surface area and porosity, which can provide a suitable growth environment and medium for microorganisms, and at the same time, expand the contact area of the pollutant-containing gas and the microorganisms, adsorb and concentrate the pollutant-containing gas to supply the microorganisms for degradation, achieve the effect of purifying the gas, and form a composite material with good mechanical properties, not easy to collapse, and good purification effect. The microbial composite material of the present application has good mechanical stability, long service life, good effect of degrading pollutants, and high purification efficiency.

[0142] Further, the microbial composite material obtained by mixing the microorganisms and the carrier material at a suitable ratio has better pollutant degradation effect and smaller wind resistance. If the microorganisms are too much, the filler will be less, which will affect the formation, the medium for the reproduction of microorganisms will be less, which will affect the contact area of the pollutant-containing gas and the microorganisms, and further affect the purification effect; if the microorganisms are too few, the purification efficiency will be affected. In addition, the carrier material used in the embodiment of the present application can also provide nutrients for the growth and reproduction of microorganisms, so as to maintain the amount of microorganisms contained in the composite material, realize the recycling of the composite material, maintain the stability of the purification effect, have a long service life, low purification cost, and because the carrier material can be consumed and utilized by microorganisms, the composite material will not cause secondary pollution after use, harmless to the environment and human health, green and environmentally friendly.

[0143] The microbial filter screen structure obtained by using the microbial composite material in the embodiment of the present application has the advantages of simple structure, good formability of the filtering structure, low operation cost, long service life, low wind resistance, high degradation and purification efficiency, and good degradation stability, and is suitable for treating various types of pollutants, especially for treating various VOCs, including low-concentration organic waste gas and high-concentration volatile organic compounds, etc. In the microbial filter screen in the embodiment of the present application, the filtering structure is fixed by using a fixing structure, so as to avoid the collapse of the filtering structure, and the fixing structure used will affect the wind resistance, but will not affect the degradation effect, and the material and thickness of the fixing structure can be adjusted according to the actual application requirements.

[0144] In addition, the microbial filter screen in the embodiment of the present application is made into a gas purification assembly, which has the advantages of low operation cost, long service life, high degradation and purification efficiency, and good degradation stability, and can effectively degrade the pollutants in the gas, especially VOCs, to obtain purified gas. The gas purification assembly is used for purifying VOC-containing gas, and the formed purification method can effectively degrade various types of VOCs, so as to realize the effective purification of VOC-containing gas.

Claims

1. A microbial filter, characterized in that, It includes a fixed structure and a filtration structure, wherein the filtration structure is disposed inside the fixed structure; the filtration structure contains a microbial composite material; The fixing structure is a double-layer fixing layer, and the filtering structure is disposed between the layers of the fixing layer to form a filtering layer; the fixing layer is a continuous bending structure; the thickness of the filtering layer is 0.1~2mm; Alternatively, the fixing structure includes a fixing frame and a plurality of honeycomb grids, wherein the honeycomb grids are disposed inside the fixing frame; and the filtering structure is disposed inside the honeycomb grids. The microbial composite material comprises the following raw materials: microorganisms and a carrier material; the microorganisms are microorganisms capable of degrading pollutants; the specific surface area of ​​the carrier material is 9-60 m². 2 / g; the porosity of the carrier material is 40~80%; the microbial load is calculated based on the total protein content of the microorganisms, and the microbial load is 25~40mg / g per gram of carrier material; the carrier material includes at least one of activated carbon, activated carbon fiber, carbon molecular sieve, expanded graphite, porous graphite, carbon nanotubes, carbon aerogel, crushed stone, volcanic rock, zeolite, ceramsite, sawdust, bark, hay, peat moss, sponge, diatomaceous earth, polyethylene fiber or polyurethane; the microbial composite material is granular, and the particle size of the microbial composite material is 0.5~5mm.

2. The microbial filter according to claim 1, characterized in that, The microorganisms are obtained by domestication and screening based on the types of pollutants to be degraded.

3. The microbial filter according to claim 1, characterized in that, The microbial composite material is prepared by a method including the following steps: mixing microorganisms and carrier materials to form the microbial composite material.

4. A gas purification component, characterized in that, Includes the microbial filter as described in any one of claims 1 to 3.

5. A method for purifying VOCs-containing gases, characterized in that, This is achieved using the gas purification component described in claim 4.

6. The purification method according to claim 5, characterized in that, Includes the following steps: The gas containing VOCs is passed through the gas purification component, and the angle between the airflow direction of the VOCs-containing gas and the plane where the microbial filter in the gas purification component is located is greater than 0°.

7. The purification method according to claim 6, characterized in that, The angle between the airflow direction of the VOCs-containing gas and the plane where the microbial filter in the gas purification component is located is 30~90°.

8. The purification method according to claim 5, characterized in that, The VOCs include at least one of the following: alkanes, alkenes, alkynes, aromatics, halogenated hydrocarbons, alcohols, aldehydes, ethers, ketones, acids, or esters.

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