A biological filter and a method for treating VOCs and malodorous gases

Abstract

The present invention discloses a biofilter and a method for treating VOCs and malodorous gases. The biofilter comprises a second spray chamber, which is arranged from bottom to top in sequence as a second water storage tank, a second air distribution layer, a second filler layer, and a second spray layer. The second filler layer is arranged from top to bottom as first, second, and third movable bacterial species biofilm filler layers, and a plurality of stirring devices are arranged in the first and second movable bacterial species biofilm filler layers. The method is to treat VOCs and malodorous gases by using a biofilter. The biofilter of the present invention has the advantages of high filler utilization rate, stable operation, low energy consumption, low operating cost, high treatment efficiency, good purification effect, and long service life. It can be widely used to treat different components of VOCs and malodorous gases in scenes such as industrial plants, sewage treatment, food processing industry, and garbage removal, and can effectively remove VOCs and malodorous gases in exhaust gas, and improve the air environment of polluted factory areas and living areas.

Description

Technical Field

[0001] The invention belongs to the field of VOCs and malodorous gas treatment, and relates to a biofilter and a method for treating VOCs and malodorous gas. Background Art

[0002] VOCs and malodorous gases come from many sources, and their components are closely related to the process of the source, so their components are quite different, including alcohols, ketones, alkanes, benzene series, eight kinds of malodorous gases and other pollutants. If VOCs and malodorous gases are directly discharged into human living areas, it will cause people to feel unhappy at the least, increase the probability of illness, and even lead to poisoning or serious diseases.

[0003] At present, the methods of treating VOCs and malodorous substances are organized collection and treatment and unorganized treatment. Unorganized treatment mainly includes spraying plant deodorants, hypochlorous acid solutions and other methods. Organized collection and treatment include physical method, chemical method and biological method. Among them, the physical method mainly includes physical adsorption and recovery, and the main representative is the activated carbon adsorption process. However, the maintenance cost of this process is extremely high, and the filler needs to be replaced frequently, and there are many limiting factors. Representative processes of chemical methods include RTO, RCO, chemical scrubbers, photocatalysis and other technologies. Most of these processes have high energy consumption per unit for treating waste gas, or the treatment effect is poor. Representative processes of biological methods include biotrickling filtration, biofilter and other technologies. They degrade pollutants in waste gas and purify waste gas by screening microorganisms in biological fillers and forming biofilms. They have the advantages of good treatment effect, low secondary pollution and low operating cost, which are in line with the concept of environmental protection and sustainable development. However, the existing biofilter still has the following defects: (a) As the equipment runs for a longer time, the microbial biofilm ages and falls off, which reduces the specific surface area of ​​the filler and causes the filler to become compacted; (b) As the filler becomes compacted, the pressure loss of the filler increases, and phenomena such as channeling occur; (c) With the emergence of channeling, the load of the fan increases, the treatment efficiency decreases, and the treatment effect deteriorates, which easily leads to the problem of substandard treatment effect and difficulty in stably treating odor; (d) When the filler is replaced, or after the equipment is shut down, or during intermittent operation, the number of biological strains decreases sharply, and the biofilm easily loses its activity. Furthermore, when the equipment is restarted or operated again, the strains need to be re-cultivated and domesticated, which is time-consuming and labor-intensive, and will also increase the treatment cost and easily cause secondary pollution.

[0004] Therefore, how to improve the utilization rate of fillers and promote the stable operation of biofilters is of great significance for reducing the operating costs of biofilters and improving their treatment efficiency and effect on VOCs and odorous gases. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a biofilter with high filler utilization, stable operation, low energy consumption, low operating cost, high treatment efficiency, good purification effect and long service life. A method for treating VOCs and malodorous gases using a biofilter is also provided.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A biological filter tank comprises a second box body, the second box body comprises a second air inlet chamber and a second spray chamber; the second spray chamber is sequentially arranged as a second water storage tank, a second air distribution layer, a second filler layer and a second spray layer from bottom to top; the second air inlet chamber is connected with the second spray chamber through the second air distribution layer; the second filler layer is sequentially arranged as a first movable bacterial biofilm filler layer, a second movable bacterial biofilm filler layer and a third movable bacterial biofilm filler layer from top to bottom; a plurality of stirring devices are arranged in both the first movable bacterial biofilm filler layer and the second movable bacterial biofilm filler layer.

[0008] As a further improvement of the above technical solution: the first movable bacteria biofilm filling layer, the second movable bacteria biofilm filling layer and the third movable bacteria biofilm filling layer are all formed by stacking single-component filling layers.

[0009] As a further improvement of the above technical solution: a porous partition is provided at the bottom of the single-component filler layer, so that a buffer layer is formed between two adjacent single-component filler layers; the height of the buffer layer is 10cm to 15cm.

[0010] As a further improvement of the above technical solution: the number of layers of the single-component filler layer is 1 to 6 layers.

[0011] As a further improvement of the above technical solution: the single-component filler layers of the first movable bacteria biofilm filler layer and the second movable bacteria biofilm filler layer are both filled with movable fillers, and the single-component filler layer of the third movable bacteria biofilm filler layer is filled with movable or fixed fillers.

[0012] As a further improvement of the above technical solution: the density of the filler in the single-component filler layer under static load is 0.1t / m 3 ~0.9t / m 3 .

[0013] As a further improvement of the above technical solution: the filler is one of polyurethane, volcanic rock, ceramsite, hollow ball and bamboo charcoal.

[0014] As a further improvement of the above technical solution: the particle size of the polyurethane is 10mm-40mm; the particle size of the volcanic rock is 10mm-20mm; the particle size of the ceramsite is 15mm-30mm; the particle size of the hollow ball is 38mm-50mm; the material of the hollow ball is PP; the particle size of the bamboo charcoal is 5mm-15mm.

[0015] As a further improvement of the above technical solution: when the filler is polyurethane, the thickness of the polyurethane in the single-component filler layer (single-layer thickness) is 0.4m-1.0m; the density of the polyurethane in the single-component filler layer under static load is 0.1t / m 3 ~0.15t / m 3 .

[0016] As a further improvement of the above technical solution: when the filler is volcanic rock, the thickness of the volcanic rock in the single-component filler layer is 0.4m-1.0m; the density of the volcanic rock in the single-component filler layer under static load is 0.7t / m 3 ~0.9t / m 3 .

[0017] As a further improvement of the above technical solution: when the filler is ceramsite, the thickness of the ceramsite in the single-component filler layer is 0.3m-0.8m; the density of the ceramsite in the single-component filler layer under static load is 0.4t / m 3 ~0.7t / m 3 .

[0018] As a further improvement of the above technical solution: when the filler is a hollow ball, the thickness of the hollow ball in the single-component filler layer is 0.4m-1.0m; the density of the hollow ball in the single-component filler layer under static load is 0.15t / m 3 ~0.25t / m 3 .

[0019] As a further improvement of the above technical solution: when the filler is bamboo charcoal, the thickness of the bamboo charcoal in the single-component filler layer is 0.2m-0.8m; the density of the bamboo charcoal in the single-component filler layer under static load is 0.2t / m 3 ~0.4t / m 3 .

[0020] As a further improvement of the above technical solution: the stirring device includes a stirring rod, and the stirring rod is installed on the top of the second box; a plurality of hubs are fixed on the stirring rod.

[0021] As a further improvement of the above technical solution: the hub is located in the single-component filling layer of the first movable bacteria biofilm filling layer and the second movable bacteria biofilm filling layer, and when the number of single-component filling layers is ≥2 layers, the hub is not arranged in the bottom single-component filling layer of the second movable bacteria biofilm filling layer.

[0022] As a further improvement of the above technical solution: each of the hubs is equipped with at least one stirring blade, and when in use, the stirring blade is horizontally arranged in the single-component filler layer; the stirring blade consists of a horizontal portion and an inclined portion; the angle between the horizontal portion and the inclined portion is 30° to 75°; the horizontal portion is parallel to the horizontal plane; the length of the stirring blade is 0.25m to 0.75m; the width of the stirring blade is 0.12m to 0.2m; the thickness of the stirring blade is 16mm to 25mm.

[0023] As a further improvement of the above technical solution: the material of the stirring blade is one of 304 stainless steel, galvanized steel, and fiberglass;

[0024] As a further improvement of the above technical solution: the stirring rod is also connected to a driving mechanism; the driving mechanism includes a motor, and the motor is installed on the top of the second box; the output end of the motor is connected to the stirring rod.

[0025] As a further improvement of the above technical solution: when the filler is polyurethane, the corresponding thickness of the stirring blade is 16mm to 18mm. When the filler is volcanic rock, the corresponding thickness of the stirring blade is 22mm to 25mm. When the filler is ceramsite, the corresponding thickness of the stirring blade is 18mm to 22mm. When the filler is hollow ball, the corresponding thickness of the stirring blade is 18mm to 20mm. When the filler is bamboo charcoal, the corresponding thickness of the stirring blade is 16mm to 20mm.

[0026] As a further improvement of the above technical solution: a movable scraper is also provided above the first movable bacterial biofilm filling layer; the length of the scraper is 1m to 3m; the height between the bottom and the top of the scraper is 15cm to 25cm; the angle between the scraper and the horizontal plane is 60° to 90°.

[0027] As a further improvement of the above technical solution: the scraper is made of one of 304 stainless steel, galvanized steel and fiberglass.

[0028] As a further improvement of the above technical solution: a waste gas outlet is also provided on the top of the second box body; the waste gas outlet is communicated with the second spray layer; and a second gas differential pressure gauge is connected to the waste gas outlet.

[0029] As a further improvement of the above technical solution: a second spray assembly is provided in the second spray layer; the second spray assembly includes a second spray pipe, and the second spray pipe is fixed on the top of the second box; a plurality of second spray ports are also provided below the second spray pipe; and a temperature sensor is also connected in the second spray layer.

[0030] As a further improvement of the above technical solution: the inlet end of the second spray pipe is connected to a second spray liquid storage tank; the second spray liquid storage tank is connected to the second water storage tank; a second spray liquid delivery pump is provided on the pipeline between the second spray pipe and the second spray liquid storage tank; the second spray liquid storage tank is also connected to a strain storage box and a liquid level meter.

[0031] As a further improvement of the above technical solution: it also includes a first box body and an intelligent control box.

[0032] As a further improvement of the above technical solution: the first box body includes a first air inlet cavity and a first spray cavity; the first spray cavity is configured from bottom to top as a first water storage tank, a first air distribution layer, a first filler layer, and a first spray layer.

[0033] As a further improvement of the above technical solution: an exhaust gas inlet is provided on the top of the first box body; the exhaust gas inlet is communicated with the first air inlet cavity; and a first gas differential pressure gauge is connected to the exhaust gas inlet.

[0034] As a further improvement of the above technical solution: the first air inlet cavity is connected to the first spray cavity through the first air distribution layer; the first spray cavity is connected to the second air inlet cavity through the first spray layer.

[0035] As a further improvement of the above technical solution: the first filler layer includes at least two layers of grid plates, the grid plates are provided with fillers, the fillers are hollow balls; the material of the hollow balls is PP; the thickness of the fillers on the grid plates is 0.5m~1.0m; there are gaps between the grid plates; the height of the gaps is 10cm~15cm.

[0036] As a further improvement of the above technical solution: a first spray assembly is provided in the first spray layer; the first spray assembly includes a first spray pipe, and the first spray pipe is fixed on the top of the first box; and a plurality of first spray ports are provided below the first spray pipe.

[0037] As a further improvement of the above technical solution: the inlet end of the first spray pipe is connected to the first spray liquid storage tank; the first spray liquid storage tank is connected to the first water storage tank; a first spray liquid delivery pump is provided on the pipeline between the first spray pipe and the first spray liquid storage tank; the first spray liquid storage tank is also connected to a micro-nano bubble generator.

[0038] As a further improvement of the above technical solution: the intelligent control box is electrically connected to the first gas differential pressure gauge, the first spray liquid delivery pump, the second gas differential pressure gauge, the second spray liquid delivery pump, and the motor respectively; the intelligent control box is a PLC control device or a DCS control device.

[0039] As a general technical concept, the present invention also provides a method for treating VOCs and malodorous gases, using the above-mentioned biological filter to treat VOCs and malodorous gases.

[0040] As a further improvement of the above technical solution: when using a biological filter to treat VOCs and malodorous gases, the following steps are included:

[0041] S1, introducing VOCs and malodorous gases into the first box from the exhaust gas inlet, turning on the first spray liquid delivery pump and the micro-nano bubble generator, and spraying the micro-nano bubble water in the first spray liquid storage pool (15) onto the first filler layer to wash the VOCs and malodorous gases;

[0042] S2, the VOCs and malodorous gases washed in step S1 are introduced into the second box through the second air inlet cavity, the second spray liquid delivery pump is turned on, and the mixed bacterial liquid in the second spray liquid storage tank (25) is sprayed onto the second packing layer to wash the VOCs and malodorous gases, thereby completing the purification treatment of the VOCs and malodorous gases.

[0043] As a further improvement of the above technical solution: in step S2, during the elution process, the residence time of the VOCs and malodorous gases in the second packing layer is 10s to 60s.

[0044] As a further improvement of the above technical solution: the elution process also includes the following processing: using the first gas differential pressure gauge and the second gas differential pressure gauge to detect the pressure loss at both ends of the waste gas inlet and outlet of the biological filter, and obtaining the pressure loss value during the operation process. When the pressure loss value during the operation exceeds 15% to 30% of the initial design pressure loss value, stop the air intake and elution, start the stirring device to stir the filler in the second filler layer, start the air intake and elution, until the measured pressure difference value of the first gas differential pressure gauge and the second gas differential pressure gauge is 60% to 100% of the design pressure difference value, and remains stable for 0.05h to 1h, otherwise, stop the air intake and elution, and continue to stir the filler in the second filler layer.

[0045] As a further improvement of the above technical solution: the time of a single stirring treatment is 5 minutes to 25 minutes; during the stirring treatment, the rotation speed of the stirring device is controlled to be 15 rpm to 30 rpm.

[0046] As a further improvement of the above technical solution: after the stirring treatment is completed, the following treatment is also included: adding spray liquid (the spray liquid contains nutrients required for microbial growth) to the second water storage tank and the second spray liquid storage tank, adding solid bacterial agent in the bacterial strain storage box, mixing with the spray liquid to form a mixed bacterial liquid, starting the second spray liquid delivery pump, spraying the mixed bacterial liquid onto the second filler layer to acclimate the bacterial strain until a biofilm is formed in the filler; during the acclimatization process, spraying is performed for 2 to 6 hours every day.

[0047] As a further improvement of the above technical solution: in step S2, before starting the elution, the following treatment is also included: adding spray liquid (the spray liquid contains nutrients required for microbial growth) to the second water storage tank and the second spray liquid storage tank, adding the solid bacterial agent in the bacterial strain storage box, mixing with the spray liquid to form a mixed bacterial liquid, starting the second spray liquid delivery pump, spraying the mixed bacterial liquid onto the second filler layer to activate the bacterial strain until a biofilm is formed in the filler, and using intermittent air intake to introduce VOCs and malodorous gases into the second box to cultivate the biofilm.

[0048] As a further improvement of the above technical solution: during the activation treatment process, spraying is performed for 20 minutes to 40 minutes every day for 2 to 4 days.

[0049] As a further improvement of the above technical solution: VOCs and malodorous gases are introduced into the second box from 7:00 to 19:00 every day during the cultivation process.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] (1) In the biofilter of the present invention, a second water storage tank, a second air distribution layer, a second filler layer, and a second spray layer are arranged from bottom to top in the spray chamber of the box body, and the second filler layer is sequentially composed of a first movable bacterial species biofilm filler layer, a second movable bacterial species biofilm filler layer, and a third movable bacterial species biofilm filler layer from top to bottom. When VOCs and malodorous gases enter the air distribution layer through the air inlet chamber, they pass through the third movable bacterial species biofilm filler layer, the second movable bacterial species biofilm filler layer, the first movable bacterial species biofilm filler layer, and the spray layer in turn, and the VOCs and malodorous gases are effectively removed under the joint action of the spray liquid and the microorganisms. At the same time, a plurality of stirring devices are arranged in the first movable bacterial species biofilm filler layer and the second movable bacterial species biofilm filler layer. By utilizing the stirring device, the VOCs and malodorous gases are effectively removed. The device stirs the filler. On the one hand, it can make the filler return to its original loose state and remove a part of the biofilm attached to the surface of the filler that has lost its activity, which is beneficial to restore the specific surface area of ​​the filler. It can not only promote the contact between VOCs and malodorous gases and the spray liquid, but also promote the contact between VOCs and malodorous gases and the biofilm, thereby improving the treatment efficiency of the spray liquid and microorganisms to VOCs and malodorous gases. On the other hand, it can also restore the pressure of the biofilter to the original design level, which is beneficial to improving the utilization rate of the filler and the biofilm, while reducing the treatment energy consumption, it can also increase the treatment amount of VOCs and malodorous gases, thereby reducing the treatment cost, and ultimately conducive to the stable operation of the biofilter, and prolonging the service life of the biofilter, and expanding the use prospects of the biofilter. The biofilter of the present invention has the advantages of high filler utilization, stable operation, low energy consumption, low operating cost, high treatment efficiency, good purification effect, long service life, etc. It can be used to treat VOCs and malodorous gases of different components, and can effectively remove VOCs and malodorous gases in exhaust gas, which is of great significance for improving the air environment of polluted factory areas and living areas.

[0052] (2) In the biofilter of the present invention, by optimizing the filling method, filling density, particle size and thickness of the filler in the second filler layer, it is not only conducive to the formation of a biofilm with high biological activity on the filler surface, but also conducive to the formation of a filler layer with rich pore structure and appropriate thickness, thereby facilitating the improvement of the treatment capacity and treatment efficiency of VOCs and malodorous gases by the spray liquid and microorganisms.

[0053] (3) In the biofilter of the present invention, a plurality of groups of stirring blades are respectively arranged in the first movable bacterial biofilm filling layer and the second movable bacterial biofilm filling layer, and by optimizing the structure, number, length and thickness of the stirring blades, it is possible to avoid destroying the original biofilm structure as much as possible while restoring the original loose structure of the filler, thereby enabling the biofilter to quickly restore its original purification effect.

[0054] (4) In the biofilter of the present invention, a movable scraper is provided above the first movable bacterial biofilm filler layer, and the scraper is used to level the uneven surface of the filler, which is helpful to avoid the formation of channel flow and to restore the original function of the filler layer.

[0055] (5) The biofilter of the present invention also includes a first box and an intelligent control box, wherein the VOCs and malodorous gases are pre-treated by the air inlet chamber and the spray chamber in the first box, which can effectively remove the particulate matter and soluble gas in the VOCs and malodorous gases, which is beneficial to improving the purification effect of the second box. At the same time, in the first box, the micro-nano bubble liquid produced by the micro-nano bubble generator is used to spray the VOCs and malodorous gases, and the micro-nano bubbles can be used to decompose the pollutants in the VOCs and malodorous gases, which is beneficial to reduce the concentration of pollutants in the circulating water, and can also reduce the water consumption and drainage volume. In addition, under the regulation of the intelligent control box, the automatic control of the biological pool can also be achieved.

[0056] (6) The method for treating VOCs and malodorous gases of the present invention adopts the biofilter of the present invention to treat VOCs and malodorous gases, which can effectively remove various VOCs and malodorous gases in the waste gas, has the advantages of simple process, convenient operation, low cost, high treatment efficiency, good removal effect, etc., and can be widely used for purifying VOCs and malodorous gases from industrial plants, sewage treatment, food processing industry, garbage collection and other scenes. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0058] Figure 1 This is a schematic diagram of the structure of the biofilter in Example 1 of the present invention.

[0059] Figure 2 This is a top view of the biofilter in Example 1 of the present invention.

[0060] Figure 3 for Figure 2 Cross-section view at AA in the middle.

[0061] Figure 4 for Figure 2 Cross-section view at the middle BB.

[0062] Figure 5 This is a flow diagram of gas in the biofilter of Example 1 of the present invention.

[0063] Figure 6 1 is a top view of the stirring device in Example 1 of the present invention.

[0064] Figure 7 This is a side view of the stirring device in Example 1 of the present invention.

[0065] Figure 8 This is a front view of the stirring device in Example 1 of the present invention.

[0066] Fig. 9 This is a line graph of operating parameters of the biofilter in Example 1 of the present invention.

[0067] Fig.10 This is a line graph of operating parameters of the biofilter in Example 2 of the present invention.

[0068] Legend:

[0069] 1. First housing; 11. First air inlet cavity; 12. First spray cavity; 121. First water storage tank; 122. First air distribution layer; 123. First filler layer; 124. First spray layer; 1241. First spray pipe; 1242. First spray port; 13. Waste gas inlet; 14. First gas differential pressure gauge; 15. First spray liquid storage tank; 16. First spray liquid delivery pump; 17. Micro-nano bubble generator; 2. Second housing; 21. Second air inlet cavity; 22. Second spray cavity; 221. Second water storage tank; 222. Second air distribution layer; 223. Second filler layer; 2231. First movable bacterial biofilm filler layer; 223 2. Second movable bacterial biofilm filling layer; 2233. Third movable bacterial biofilm filling layer; 2234. Scraper; 2235. Porous partition; 224. Second spray layer; 2241. Second spray pipe; 2242. Second spray port; 2243. Temperature sensor; 23. Exhaust gas outlet; 24. Second gas differential pressure gauge; 25. Second spray liquid storage tank; 26. Second spray liquid delivery pump; 27. Bacteria storage box; 28. Liquid level gauge; 29. ​​Stirring device; 291. Stirring rod; 292. Wheel hub; 294. Stirring blade; 2941. Horizontal part; 2942. Inclined part; 295. Motor; 3. Intelligent control box. DETAILED DESCRIPTION

[0070] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] In the description of the present invention, it should be noted that the terms "center", "up", "down", "front", "back", "left", "right", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0072] Example 1

[0073] like Figure 1 , Figure 2 and Figure 4 As shown, the biological filter tank of this embodiment includes a second box body 2, and the second box body 2 includes a second air inlet chamber 21 and a second spray chamber 22; the second spray chamber 22 is sequentially configured as a second water storage tank 221, a second air distribution layer 222, a second filler layer 223, and a second spray layer 224 from bottom to top; the second air inlet chamber 21 is connected to the second spray chamber 22 through the second air distribution layer 222; the second filler layer 223 is sequentially configured as a first movable bacteria biofilm filler layer 2231, a second movable bacteria biofilm filler layer 2232, and a third movable bacteria biofilm filler layer 2233 from top to bottom; a plurality of stirring devices 29 are provided in both the first movable bacteria biofilm filler layer 2231 and the second movable bacteria biofilm filler layer 2232.

[0074] In this embodiment, the first movable bacterial biofilm filling layer 2231, the second movable bacterial biofilm filling layer 2232 and the third movable bacterial biofilm filling layer 2233 are all formed by stacking single-component filling layers; a porous partition 2235 is provided at the bottom of the single-component filling layer, so that a buffer layer is formed between two adjacent single-component filling layers, and the height of the buffer layer is 10 cm; the number of layers of the single-component filling layer is 1.

[0075] In this embodiment, the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is filled with movable fillers, wherein the filler is ceramsite, and the particle size of the ceramsite is 15mm-30mm; the thickness of the ceramsite in the single-component filler layer is 0.5m, and the density of the ceramsite under static load is 0.4t / m 3 .

[0076] In another embodiment, according to different scenes, different components of VOCs and malodorous gases, the type, thickness and density of the filler in the single-component filler layer of the first movable bacterial strain biofilm filler layer 2231 can also be adjusted. For example, the filler filled in the single-component filler layer of the first movable bacterial strain biofilm filler layer 2231 can be one of polyurethane, volcanic rock, hollow balls and bamboo charcoal, and the particle size of polyurethane is 10mm to 40mm. For example, the particle size of polyurethane is 10mm, 20mm, 30mm, 40mm, and the particle size of volcanic rock ... The particle size of the rock is 10mm-20mm, the particle size of the hollow ball (made of PP) is 38mm-50mm, for example, the particle size of the hollow ball is 38mm, 40mm, 45mm, 50mm, and the particle size of the bamboo charcoal is 5mm-15mm; at the same time, when the filler is polyurethane, the thickness of the polyurethane in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is 0.4m-1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the polyurethane under static load is 0.1t / m 3 ~0.15t / m 3 For example, the density under static load is 0.1t / m 3 , 0.12t / m 3 、0.13t / m 3 , 0.15t / m 3 When the filler is volcanic rock, the thickness of the volcanic rock in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is 0.4m to 1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the volcanic rock under static load is 0.7t / m 3 ~0.9t / m 3 For example, the density at static load is 0.7t / m 3 , 0.75t / m 3 , 0.8t / m 3 、0.9t / m 3 When the filler is a hollow ball, the thickness of the hollow ball in the first movable bacterial biofilm filler layer 2231 is 0.4m to 1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the hollow ball under static load is 0.15t / m 3 ~0.25t / m 3 For example, the density at static load is 0.15t / m 3 , 0.2t / m 3 , 0.23t / m 3 , 0.25t / m 3When the filler is bamboo charcoal, the thickness of the bamboo charcoal in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is 0.2m to 0.8m, for example, the thickness is 0.2m, 0.4m, 0.6m, 0.8m, and the density of the bamboo charcoal under static load is 0.2t / m 3 ~0.4t / m 3 For example, the density under static load is 0.2t / m 3 , 0.22t / m 3 , 0. 3t / m 3 , 0.4t / m 3 .

[0077] In this embodiment, the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is filled with a movable filler, wherein the filler is polyurethane, and the particle size of the polyurethane is 15 mm; the thickness of the polyurethane in the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is 0.8 m, and the density of the polyurethane under static load is 0.15 t / m 3 .

[0078] In another embodiment, according to different scenarios, different components of VOCs and malodorous gases, the type, thickness and density of the filler in the single-component filler layer of the second movable bacterial strain biofilm filler layer 2232 can also be adjusted. For example, the filler filled in the single-component filler layer of the second movable bacterial strain biofilm filler layer 2232 can be one of ceramsite, volcanic rock, hollow ball and bamboo charcoal. The particle size of the ceramsite is 15mm~30mm, the particle size of the volcanic rock is 10mm~20mm, the particle size of the hollow ball is 38mm~50mm, and the particle size of the bamboo charcoal is 5mm~15mm; at the same time, when the filler is polyurethane, the thickness of the ceramsite in the single-component filler layer of the second movable bacterial strain biofilm filler layer 2232 is 0.3m~0.8m, for example, the thickness is 0.3m, 0.4m, 0.6m, 0.8m, and the density of the ceramsite under static load is 0.1t / m 3 ~0.15t / m 3 For example, the density under static load is 0.1t / m 3 , 0.12t / m 3 、0.13t / m 3 , 0.15t / m 3 When the filler is volcanic rock, the thickness of the volcanic rock in the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is 0.4m to 1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the volcanic rock under static load is 0.7t / m 3 ~0.9t / m 3 For example, the density at static load is 0.7t / m 3 、0.72t / m 3, 0.8t / m 3 、0.9t / m 3 When the filler is a hollow ball, the thickness of the hollow ball in the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is 0.4m to 1.0m, and the density of the hollow ball under static load is 0.15t / m 3 ~0.25t / m 3 For example, the density at static load is 0.15t / m 3 、0.18t / m 3 , 0.23t / m 3 , 0.25t / m 3 When the filler is bamboo charcoal, the thickness of the bamboo charcoal in the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is 0.2m to 0.8m, for example, the thickness is 0.2m, 0.4m, 0.6m, 0.8m, and the density of the bamboo charcoal under static load is 0.2t / m 3 ~0.4t / m 3 For example, the density under static load is 0.2t / m 3 , 0.22t / m 3 , 0.3t / m 3 , 0.4t / m 3 .

[0079] In this embodiment, the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is filled with a movable filler, wherein the filler is bamboo charcoal, and the particle size of the bamboo charcoal is 5mm to 15mm; the thickness of the bamboo charcoal in the third movable bacterial biofilm filler layer 2233 is 0.4m, and the density of the bamboo charcoal under static load is 0.25t / m 3 .

[0080] In another embodiment, according to different scenarios, different components of VOCs and malodorous gases, the type, thickness and density of the filler in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 can also be adjusted. For example, the filler filled in the third movable bacterial biofilm filler layer 2233 can be one of polyurethane, volcanic rock, hollow ball and bamboo charcoal. The particle size of polyurethane is 10mm~40mm, the particle size of volcanic rock is 10mm~20mm, the particle size of hollow ball is 38mm~50mm, and the particle size of ceramsite is 15mm~30mm. At the same time, when the filler is polyurethane, the thickness of polyurethane in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is 0.4m~1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of polyurethane under static load is 0.1t / m 3 ~0.15t / m 3 For example, the density under static load is 0.1t / m 3 , 0.12t / m3 、0.13t / m 3 , 0.15t / m 3 When the filler is volcanic rock, the thickness of the volcanic rock in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is 0.4m to 1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the volcanic rock under static load is 0.7t / m 3 ~0.9t / m 3 For example, the density at static load is 0.7t / m 3 、0.72t / m 3 , 0.8t / m 3 、0.9t / m 3 When the filler is a hollow ball, the thickness of the hollow ball in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is 0.4m to 1.0m, for example, the thickness is 0.4m, 0.6m, 0.8m, 1m, and the density of the hollow ball under static load is 0.15t / m 3 ~0.25t / m 3 For example, the density at static load is 0.15t / m 3 、0.18t / m 3 , 0.23t / m 3 , 0.25t / m 3 When the filler is ceramsite, the thickness of the ceramsite in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is 0.3m to 0.8m, for example, the thickness is 0.3m, 0.4m, 0.6m, 0.8m, and the density of the ceramsite under static load is 0.4t / m 3 ~0.7t / m 3 For example, the density under static load is 0.4t / m 3 , 0.5t / m 3 , 0.6t / m 3 、0.7t / m 3 .

[0081] In another embodiment, the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is filled with fixed fillers.

[0082] In this embodiment, a movable scraper 2234 is also provided above the first movable bacterial biofilm filling layer 2231; the length of the scraper 2234 is 1m to 3m, specifically, the length is 1m; the height between the bottom and the top of the scraper 2234 is 15cm to 25cm, specifically, the height is 20cm; the angle between the scraper 2234 and the horizontal plane is 60° to 90°, specifically, the angle is 60°.

[0083] In this embodiment, the scraper 2234 is made of 304 stainless steel. In other embodiments, the scraper 2234 may be made of galvanized steel or fiberglass.

[0084] In this embodiment, a waste gas outlet 23 is further provided on the top of the second box body 2 ; the waste gas outlet 23 is communicated with the second spray layer 224 ; and a second gas differential pressure gauge 24 is connected to the waste gas outlet 23 .

[0085] In this embodiment, a second spray assembly is provided in the second spray layer 224; the second spray assembly includes a second spray pipe 2241, and the second spray pipe 2241 is fixed on the top of the second box 2; a plurality of second spray ports 2242 are provided below the second spray pipe 2241; and a temperature sensor 2243 is also connected to the second spray layer 224.

[0086] In this embodiment, the inlet end of the second spray pipe 2241 is connected to the second spray liquid storage tank 25; the second spray liquid storage tank 25 is connected to the second water storage tank 221; a second spray liquid delivery pump 26 is provided on the pipeline between the second spray pipe 2241 and the second spray liquid storage tank 25; the second spray liquid storage tank 25 is also connected to a strain storage box 27 and a liquid level meter 28.

[0087] like Figure 1 , Figure 2 and Figure 3 As shown, in this embodiment, a first box body 1 and an intelligent control box 3 are also included.

[0088] In this embodiment, the first box body 1 includes a first air inlet cavity 11 and a first spray cavity 12; the first spray cavity 12 is sequentially configured from bottom to top as a first water storage tank 121, a first air distribution layer 122, a first filler layer 123, and a first spray layer 124.

[0089] In this embodiment, an exhaust gas inlet 13 is provided on the top of the first box body 1 ; the exhaust gas inlet 13 is communicated with the first air inlet chamber 11 ; and a first gas differential pressure gauge 14 is connected to the exhaust gas inlet 13 .

[0090] In this embodiment, the first air inlet cavity 11 is connected to the first spray cavity 12 through the first air distribution layer 122 ; the first spray cavity 12 is connected to the second air inlet cavity 21 through the first spray layer 124 .

[0091] In this embodiment, the first filler layer 123 includes two layers of grid plates, and fillers are provided on the grid plates. The fillers are hollow balls, and the material of the hollow balls is PP. The thickness of the fillers on the grid plates is 0.5m~1.0m. Specifically, the thickness of the fillers is 0.5m. There are gaps between the grid plates, and the height of the gaps is 10cm.

[0092] In this embodiment, a first spray assembly is provided in the first spray layer 124 ; the first spray assembly includes a first spray pipe 1241 , and the first spray pipe 1241 is fixed on the top of the first box body 1 ; a plurality of first spray ports 1242 are further provided below the first spray pipe 1241 .

[0093] In this embodiment, the inlet end of the first spray pipe 1241 is connected to the first spray liquid storage tank 15; the first spray liquid storage tank 15 is connected to the first water storage tank 121; a first spray liquid delivery pump 16 is provided on the pipeline between the first spray pipe 1241 and the first spray liquid storage tank 15; and the first spray liquid storage tank 15 is also connected to a micro-nano bubble generator 17.

[0094] In this embodiment, the intelligent control box 3 is electrically connected to the first gas differential pressure gauge 14 , the first spray liquid delivery pump 16 , the second gas differential pressure gauge 24 , the second spray liquid delivery pump 26 , and the motor 295 , respectively.

[0095] In this embodiment, a through-beam photoelectric sensor is provided in the bacterial strain storage box 27 , and the through-beam photoelectric sensor is electrically connected to the intelligent control box 3 .

[0096] In this embodiment, the intelligent control box 3 is a PLC control device. In another embodiment, the intelligent control box 3 is a DCS control device.

[0097] Figure 5 FIG. 1 is a flow diagram of gas in the biofilter of Example 1 of the present invention. Figure 5 It can be seen that VOCs and malodorous gases enter the first air inlet cavity through the exhaust gas inlet. In the first air inlet cavity, the particulate pollutants in the VOCs and malodorous gases are separated from the gas under the action of gravity, and then enter the first air distribution layer from the bottom of the first air inlet cavity, and pass through the first packing layer from bottom to top. In this process, the VOCs and malodorous gases in the first packing layer are eluted with spray water in the spray component to remove water-soluble gases (such as ammonia, hydrogen sulfide, etc.), and then the VOCs and malodorous gases eluted by the first packing layer enter the first spray layer through the first spray layer. In the second air inlet cavity, the gas turns and enters the second air distribution layer of the second spray cavity from top to bottom. In the second air distribution layer, VOCs and malodorous gases are evenly dispersed and pass through the third movable bacteria biofilm filling layer, the second movable bacteria biofilm filling layer, and the first movable bacteria biofilm filling layer from bottom to top. The spray liquid and the microorganisms in the biofilm are used to adsorb, decompose and remove VOCs and malodorous gases, and finally they are discharged from the exhaust gas outlet through the second spray layer, thereby achieving effective treatment of VOCs and malodorous gases.

[0098] like Figure 1 , Figure 6 , Figure 7 and Figure 8As shown, in this embodiment, the stirring device 29 includes a stirring rod 291, which is installed on the top of the second box body 2. One end of the stirring rod 291 passes through the top of the second box body 2 and is movably installed on the second box body 2, and the other end penetrates into the single-component filler layer of the first movable bacterial strain biofilm filler layer 2231 and the second movable bacterial strain biofilm filler layer 2232; a plurality of hubs 292 are fixed on the stirring rod 291, and the number of hubs 292 is determined according to the number of layers of the single-component filler layer. Specifically, the number of hubs 292 on a single stirring rod 291 is the number of layers of the single-component filler layer-1. In this embodiment, two hubs 292 are provided on a single stirring rod 291, and the two hubs 292 are respectively located in the single-component filler layers of the first movable bacterial strain biofilm filler layer 2231 and the second movable bacterial strain biofilm filler layer 2232. In another embodiment, when the number of single-component filler layers is ≥2, the hub 292 is not provided in the bottommost single-component filler layer of the second movable bacterial biofilm filler layer 2232 .

[0099] In this embodiment, at least one stirring blade 294 is installed on each hub 292. Specifically, three stirring blades 294 are installed on each hub 292. When in use, the stirring blades 294 are horizontally arranged in the single-component filler layer.

[0100] In this embodiment, the stirring blade 294 is composed of a horizontal portion 2941 and an inclined portion 2942. The angle between the horizontal portion 2941 and the inclined portion 2942 is 30° to 75°, specifically, the angle is 60°, and the horizontal portion 2941 is parallel to the horizontal plane.

[0101] In this embodiment, the length of the stirring blade 294 is 0.25m to 0.75m, specifically, 0.5m, and at this time, the impeller diameter of the stirring device 29 is 1m. The width of the stirring blade 294 is 0.12m to 0.2m, specifically, 0.15m.

[0102] In this embodiment, the stirring blade 294 is made of 304 stainless steel. In another embodiment, the stirring blade 294 may be made of galvanized steel or fiberglass.

[0103] In this embodiment, the thickness of the stirring blade 294 is 16 mm to 25 mm. Specifically, the filler in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is expanded clay, that is, the corresponding thickness of the stirring blade 294 in the expanded clay is 18 mm, and the filler in the single-component filler layer of the second movable bacterial biofilm filler layer 2232 is polyurethane, that is, the corresponding thickness of the stirring blade 294 in the polyurethane is 16 mm.

[0104] In another embodiment, when the filler is volcanic rock, the thickness of the corresponding stirring blade 294 in the volcanic rock is 22mm~25mm, such as 22mm, 23mm, 24mm, and 25mm; when the filler is hollow spheres, the thickness of the corresponding stirring blade 294 in the hollow spheres is 18mm~20mm, such as 18mm, 19mm, and 20mm; when the filler is bamboo charcoal, the thickness of the corresponding stirring blade 294 in the bamboo charcoal is 16mm~20mm, such as 16mm, 17mm, 18mm, and 20mm.

[0105] In this embodiment, a driving mechanism is also connected to the stirring rod 291 ; the driving mechanism includes a motor 295 , which is installed on the top of the second box body 2 and is located outside the second box body; the output end of the motor 295 is connected to the stirring rod 291 .

[0106] In the biofilter of the present invention, when VOCs and malodorous gases enter the air distribution layer through the air inlet cavity, they pass through the third movable bacteria biofilm filling layer, the second movable bacteria biofilm filling layer, the first movable bacteria biofilm filling layer and the spray layer in sequence, and the VOCs and malodorous gases are effectively removed under the joint action of the spray liquid and the microorganisms. At the same time, a plurality of stirring devices are provided in the first movable bacteria biofilm filling layer and the second movable bacteria biofilm filling layer. By stirring the filler with the stirring device, on the one hand, the filler can be returned to its original loose state, and a part of the inactive biofilm attached to the surface of the filler can be removed. The biofilm is beneficial to restore the specific surface area of ​​the filler, which can not only promote the contact between VOCs and malodorous gases and the spray liquid, but also promote the contact between VOCs and malodorous gases and the biofilm, thereby improving the treatment efficiency of the spray liquid and microorganisms to VOCs and malodorous gases. On the other hand, it can also restore the pressure of the biofilter to the original design level, which is beneficial to improve the utilization rate of the filler and the biofilm, while reducing the treatment energy consumption, it can also increase the treatment amount of VOCs and malodorous gases, thereby reducing the treatment cost, and ultimately conducive to the stable operation of the biofilter, and extend the service life of the biofilter, and expand the use prospects of the biofilter. The biofilter of the present invention has the advantages of high filler utilization, stable operation, low energy consumption, low operating cost, high treatment efficiency, good purification effect, long service life, etc. It can be applied to VOCs and malodorous gases of different components, and can effectively remove VOCs and malodorous gases in exhaust gas, which is of great significance for improving the air environment of polluted factory areas and living areas.

[0107] A method for treating VOCs and malodorous gases, using the biofilter in the above embodiment to treat VOCs and malodorous gases from a wastewater treatment station of a food processing plant, comprises the following steps:

[0108] S1. Collect the odor generated by the sewage treatment process front-end regulating tank, hydrolysis acidification tank, sludge concentration tank of the sludge system, and sludge dewatering room. The air volume of the odor is 20,000m 3 / h, NH3 concentration is 42mg / m 3 , H2S concentration is 31mg / m 3 , the concentration of non-methane total hydrocarbons is 55mg / m 3 , the odor concentration is 17000. The collected odor (VOCs and malodorous gases) is introduced into the first box body 1 from the waste gas inlet 13, the first spray liquid delivery pump 16 and the micro-nano bubble generator 17 are turned on, and the micro-nano bubble water in the first spray liquid storage tank 15 is sprayed onto the first filler layer 123 to wash the VOCs and malodorous gases. During the washing process, the passing waste gas is offset by the pre-treatment spray liquid to reduce the concentration of particulate matter and soluble pollutants in the waste gas entering the biological section. The pre-washing section waste gas passes through the biofilm filler section from the top of the biological section to the bottom, and different pollutants in the waste gas are captured by fillers of different components, and then degraded into harmless substances by biological bacteria.

[0109] S2. The VOCs and malodorous gases after elution in step S1 enter the second box body 2 through the second air inlet cavity 21, and the second spray liquid delivery pump 26 is turned on to spray the mixed bacterial liquid in the second spray liquid storage tank 25 (according to actual conditions, nutrients for microbial growth and additional bacteria are added to the mixed bacterial liquid) onto the second filler layer 223 to elute the VOCs and malodorous gases, thereby completing the purification of the VOCs and malodorous gases.

[0110] In this embodiment, in step S2, during the elution process, the residence time of VOCs and malodorous gases in the second filler layer 223 is 25 seconds; the mixed bacterial solution contains nutrient solution and bacterial strains; the spraying amount and spraying rate of the mixed bacterial solution are adjusted according to actual conditions.

[0111] In this embodiment, the elution process also includes the following processing: using the first gas differential pressure gauge 14 and the second gas differential pressure gauge 24 to detect the pressure loss at both ends of the waste gas inlet and outlet of the biological filter, and obtaining the pressure loss value during the operation. When the pressure loss value during the operation exceeds 20% of the initial design pressure loss value, stop the air intake and elution, start the stirring device 29 to stir the filler in the second filler layer 223, and start the air intake and elution until the measured pressure difference value of the first gas differential pressure gauge 14 and the second gas differential pressure gauge 24 is 90% of the design pressure difference value and remains stable for 0.6 hours. Otherwise, stop the air intake and elution, and continue to stir the filler in the second filler layer 223, wherein the single stirring time is 20 minutes; during the stirring process, the speed of the stirring device 29 is controlled to be 20rpm.

[0112] In this embodiment, after the stirring treatment is completed, the following treatment is also included: adding spray liquid to the second water storage tank 221 and the second spray liquid storage tank 25, adding the solid bacterial agent in the bacterial strain storage box 27, mixing with the spray liquid to form a mixed bacterial liquid, turning on the second spray liquid delivery pump 26, spraying the mixed bacterial liquid onto the second filler layer 223 to acclimate the bacterial strain until a biofilm is formed in the filler; during the acclimatization process, spraying is performed for 2.5 hours every day, and the spraying amount is adjusted according to actual conditions.

[0113] In this embodiment, in step S2, before starting the elution, the following processing is also included: adding spray liquid to the second water storage tank 221 and the second spray liquid storage tank 25, adding the solid bacterial agent in the bacterial storage box 27, mixing with the spray liquid to form a mixed bacterial liquid, turning on the second spray liquid delivery pump 26, spraying the mixed bacterial liquid onto the second filler layer 223 to activate the bacterial strains. During the activation process, spraying is performed for 40 minutes every day for 4 days until a biofilm is formed in the filler. VOCs and malodorous gases are introduced into the second box body 2 in an intermittent air intake manner to cultivate the biofilm. During the cultivation process, VOCs and malodorous gases are intermittently introduced into the second box body 2 from 7:00 to 19:00 every day, and the biofilm is left to stand at other times to allow the biofilm to adapt to the environment and reach equilibrium, and a biofilm is formed on the filler. After the bacterial strains adapt to the intermittent operation stage, the fan and related equipment begin to operate at full load, and after a certain period of time, the bacterial strain cultivation training mode ends.

[0114] After treatment in the biofilter, the NH3 concentration is less than 3.2 mg / m 3 , treatment efficiency>92.5%; H2S concentration<1.6mg / m 3 , treatment efficiency>95%; non-methane total hydrocarbon concentration<2.8mg / m 3 , treatment efficiency 95%; odor concentration <1600, treatment efficiency >91%, the purified gas meets the relevant emission standards.

[0115] Although the treatment effect of the biofilter equipment can achieve this treatment effect in the early stage of equipment operation, as the equipment operation time increases, after 3 months of continuous operation (by adding nutrient solution and bacteria to accelerate the metabolism of the biofilm and the degree of packing compaction, it actually takes 2 to 5 years to achieve this effect), its pressure loss increases by 30% of the design value, and the air volume decreases by 20% of the design value, and its treatment effect decreases to 70%. The biofilter in this embodiment collects relevant information through the intelligent control box to determine the operating status of the device, reorganizes the compacted packing through the packing stirring system, restores it to the initial state of the device, reduces packing compaction and channeling, and the pressure loss and air volume are basically the same as the initial device. After the bacteria are biofilmed, the treatment effect can still reach more than 90%.

[0116] The biofilter operation parameter data in this embodiment are shown in Table 1, and the corresponding operation parameter diagram, as shown in Table 1. Fig. 9 As shown in the figure, the filler of the biofilter was reorganized and the bacteria were cultured during the period of 85d-93d.

[0117] Table 1 Operation parameters of the biofilter in Example 1

[0118]

[0119] Example 2

[0120] A biological filter tank is basically the same as Example 1, except that: the filler in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is volcanic rock, the particle size of the volcanic rock is 10 mm to 20 mm, the thickness of the volcanic rock in the single-component filler layer of the first movable bacterial biofilm filler layer 2231 is 0.8 m, and the density of the volcanic rock under static load is 0.7 t / m 3 The number of layers of the single-component filler layer in the second movable bacterial biofilm filler layer 2232 is 3, the thickness of the polyurethane in the single-component filler layer is 0.5m, and the density of the polyurethane under static load is 0.15t / m 3 At this time, three hubs 292 are provided on a single stirring rod 291, which are located in the single-component filler layers of the first movable bacterial biofilm filler layer 2231 and the second movable bacterial biofilm filler layer 2232, respectively, and no hub 292 is provided in the bottom single-component filler layer of the second movable bacterial biofilm filler layer 2232. The filler in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is a hollow ball with a particle size of 40 mm. The thickness of the hollow ball in the single-component filler layer of the third movable bacterial biofilm filler layer 2233 is 0.8 m, and the density of the hollow ball under static load is 0.15 t / m 3 .

[0121] A method for treating VOCs and malodorous gases, using the biofilter in the above embodiment to treat VOCs and malodorous gases generated from sewage treatment plants and workshops of pharmaceutical factories, comprises the following steps:

[0122] S1. Collect waste gas from sewage treatment stations and workshops of pharmaceutical factories. The main components of the waste gas are NH3, H2S, toluene, ethyl acetate, n-heptane, ethanol, n-propylamine, glacial acetic acid, isopropanol, and dichloromethane. The air volume of the waste gas is 2000m 3 / h, ammonia concentration is 34mg / m 3 , the hydrogen sulfide concentration is 16mg / m 3 The concentration of non-methane total hydrocarbons is 282 mg / m 3, the odor concentration is 20000. The collected waste gas (VOCs and malodorous gases) is introduced into the first box body 1 from the waste gas inlet 13, the first spray liquid delivery pump 16 and the micro-nano bubble generator 17 are turned on, and the micro-nano bubble water in the first spray liquid storage tank 15 is sprayed onto the first filler layer 123 to wash the VOCs and malodorous gases. During the washing process, the passing waste gas is offset by the pre-treatment spray liquid to reduce the concentration of particulate matter and soluble pollutants in the waste gas entering the biological section. The pre-washing section waste gas passes through the biofilm filler section from the top of the biological section to the bottom, and different pollutants in the waste gas are captured by fillers of different components, and then degraded into harmless substances by biological bacteria.

[0123] S2. The VOCs and malodorous gases after elution in step S1 enter the second box body 2 through the second air inlet cavity 21, and the second spray liquid delivery pump 26 is turned on to spray the mixed bacterial liquid in the second spray liquid storage tank 25 onto the second filler layer 223 to elute the VOCs and malodorous gases, thereby completing the purification of the VOCs and malodorous gases.

[0124] In this embodiment, in step S2, during the elution process, the residence time of VOCs and malodorous gases in the second filler layer 223 is 40 seconds; the mixed bacterial solution contains nutrient solution and bacterial strains; the spraying amount and spraying rate of the mixed bacterial solution are adjusted according to actual conditions.

[0125] In this embodiment, the following processing is also included in the elution process: the pressure loss at both ends of the waste gas inlet and outlet of the biological filter is detected by using the first gas differential pressure gauge 14 and the second gas differential pressure gauge 24 to obtain the pressure loss value during operation. When the pressure loss value during operation exceeds 15% of the initial design pressure loss value, the air intake and elution are stopped, and the stirring device 29 is started to stir the filler in the second filler layer 223. The air intake and elution are turned on until the measured pressure difference value of the first gas differential pressure gauge 14 and the second gas differential pressure gauge 24 is 95% of the design pressure difference value and remains stable for 1 hour. Otherwise, the air intake and elution are stopped, and the filler in the second filler layer 223 is continued to be stirred, wherein the time for a single stirring treatment is 25 minutes; during the stirring treatment, the speed of the stirring device 29 is controlled to be 20rpm.

[0126] In this embodiment, after the stirring treatment is completed, the following treatment is also included: adding spray liquid to the second water storage tank 221 and the second spray liquid storage tank 25, adding the solid bacterial agent in the bacterial strain storage box 27, mixing with the spray liquid to form a mixed bacterial liquid, turning on the second spray liquid delivery pump 26, spraying the mixed bacterial liquid onto the second filler layer 223 to acclimate the bacterial strain until a biofilm is formed in the filler; during the acclimatization process, spraying is performed for 2.5 hours every day.

[0127] In this embodiment, in step S2, before starting the elution, the following treatment is also included: adding spray liquid to the second water storage tank 221 and the second spray liquid storage tank 25, adding the solid bacterial agent in the bacterial storage box 27, mixing with the spray liquid to form a mixed bacterial liquid, turning on the second spray liquid delivery pump 26, spraying the mixed bacterial liquid onto the second filler layer 223 to activate the bacterial strains. During the activation process, spraying is performed for 40 minutes every day for 3 days until a biofilm is formed in the filler. VOCs and malodorous gases are introduced into the second box body 2 in an intermittent air intake manner to cultivate the biofilm. During the cultivation process, VOCs and malodorous gases are intermittently introduced into the second box body 2 from 7:00 to 19:00 every day, and the biofilm is left to stand at other times to allow the biofilm to adapt to the environment and reach equilibrium, and a biofilm is formed on the filler. After the bacterial strains adapt to the intermittent operation stage, the fan and related equipment begin to operate at full load, and after a certain period of time, the bacterial strain cultivation training mode ends.

[0128] After treatment, the NH3 concentration is <2.4mg / m 3 , treatment efficiency>92%; H2S concentration<0.8mg / m 3 , treatment efficiency>95%; non-methane total hydrocarbon concentration<17mg / m 3 , treatment efficiency>94%; odor concentration is <1600, treatment efficiency>92%, the purified gas meets the relevant emission standards.

[0129] The pressure loss, treatment efficiency and air volume of the biological section packing were measured at regular intervals and sorted out after treatment. During the first three months of operation of the equipment, the pressure loss of the packing continued to increase, while the treatment efficiency and air volume continued to decrease. The pressure loss of the packing increased by 34.4%, the treatment efficiency dropped to 74%, and the air volume decreased by 15.7%. Then the packing mixing system was started to automatically reorganize the box packing and culture the bacteria. After completion, the air volume parameters of the device were measured again, and the parameters of the device have basically returned to normal values.

[0130] The biofilter operation parameter data in this embodiment are shown in Table 2, and the corresponding operation parameter diagram, as shown in Table 2. Fig.10 As shown in the figure, the filler of the biofilter was reorganized and the bacteria were cultured during the period of 85 days to 93 days.

[0131] Table 2 Operation parameters of the biofilter in Example 2

[0132]

[0133] From the above results, it can be seen that the use of the biofilter of the present invention to treat VOCs and malodorous gases can efficiently remove various VOCs and malodorous gases in the exhaust gas, and has the advantages of simple process, convenient operation, low cost, high treatment efficiency, and good removal effect. It can be widely used to purify VOCs and malodorous gases from industrial plants, sewage treatment, food processing industry, garbage collection and other scenarios.

[0134] The above embodiments are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A biological filter, characterized in that: The invention comprises a second housing (2), wherein the second housing (2) comprises a second air inlet chamber (21) and a second spray chamber (22); the second spray chamber (22) is configured from bottom to top as a second water storage tank (221), a second air distribution layer (222), a second filler layer (223), and a second spray layer (224); the second air inlet chamber (21) is connected to the second spray chamber (22) via the second air distribution layer (222); the second filler layer (223) is configured from top to bottom as a first movable bacterial strain biofilm filler layer (2231), a second movable bacterial strain biofilm filler layer (2232), and a third movable bacterial strain biofilm filler layer (2233); the first movable bacterial strain biofilm filler layer (2231) and the second movable bacterial strain biofilm filler layer (2232) are both provided with a plurality of stirring devices (29); the first movable bacterial strain biofilm filler layer (2231), the second movable bacterial strain biofilm filler layer (2232) and the third movable bacterial strain biofilm filler layer (2233) are each ... The movable bacterial biofilm filling layer (2232) and the third movable bacterial biofilm filling layer (2233) are both formed by stacking single-component filling layers; the number of layers of the single-component filling layer is 1 to 6; the single-component filling layers of the first movable bacterial biofilm filling layer (2231) and the second movable bacterial biofilm filling layer (2232) are both filled with movable fillers, and the single-component filling layer of the third movable bacterial biofilm filling layer (2233) is filled with movable or fixed fillers; the filler is one of polyurethane, volcanic rock, ceramsite, hollow ball and bamboo charcoal; the particle size of the polyurethane is 10 mm to 40 mm; the particle size of the volcanic rock is 10 mm to 20 mm; the particle size of the ceramsite is 15 mm to 30 mm; the particle size of the hollow ball is 38 mm to 50 mm; the material of the hollow ball is PP; the particle size of the bamboo charcoal is 5 mm to 15 mm; When the filler is polyurethane, the thickness of the polyurethane in the single-component filler layer is 0.4m-1.0m; the density of the polyurethane in the single-component filler layer under static load is 0.1t / m 3 ~0.15t / m 3 ; When the filler is volcanic rock, the thickness of the volcanic rock in the single-component filler layer is 0.4m-1.0m; the density of the volcanic rock in the single-component filler layer under static load is 0.7t / m 3 ~0.9t / m 3 ; When the filler is ceramsite, the thickness of the ceramsite in the single-component filler layer is 0.3m-0.8m; the density of the ceramsite in the single-component filler layer under static load is 0.4t / m 3 ~0.7t / m 3 ; When the filler is a hollow ball, the thickness of the hollow ball in the single-component filler layer is 0.4m-1.0m; the density of the hollow ball in the single-component filler layer under static load is 0.15t / m 3 ~0.25t / m 3 ; When the filler is bamboo charcoal, the thickness of the bamboo charcoal in the single-component filler layer is 0.2m-0.8m; the density of the bamboo charcoal in the single-component filler layer under static load is 0.2t / m 3 ~0.4t / m 3 ; The stirring device (29) comprises a stirring rod (291), and the stirring rod (291) is installed on the top of the second box (2); a plurality of hubs (292) are fixed on the stirring rod (291); the hubs (292) are located in the single-component filling layers of the first movable bacterial strain biofilm filling layer (2231) and the second movable bacterial strain biofilm filling layer (2232), and when the number of the single-component filling layers is ≥ 2, the hubs (292) are not provided in the bottom single-component filling layer of the second movable bacterial strain biofilm filling layer (2232); At least one stirring blade (294) is mounted on each of the wheel hubs (292). When in use, the stirring blade (294) is horizontally arranged in the single-component filler layer. The stirring blade (294) consists of a horizontal portion (2941) and an inclined portion (2942). The angle between the horizontal portion (2941) and the inclined portion (2942) is 30° to 75°. The horizontal portion (2941) is parallel to a horizontal plane. The length of the stirring blade (294) is 0.25 m to 0.75 m. The width of the stirring blade (294) is 0.12 m to 0.2 m. The thickness of the stirring blade (294) is 16 mm to 25 mm.

2. The biofilter according to claim 1, characterized in that: A porous partition (2235) is provided at the bottom of the single-component filler layer, so that a buffer layer is formed between two adjacent single-component filler layers; the height of the buffer layer is 10 cm to 15 cm.

3. The biofilter according to claim 2, characterized in that: The material of the stirring blade (294) is one of 304 stainless steel, galvanized steel, and glass fiber reinforced plastic; The stirring rod (291) is also connected to a driving mechanism; the driving mechanism comprises a motor (295), and the motor (295) is installed on the top of the second box (2); the output end of the motor (295) is connected to the stirring rod (291).

4. The biofilter according to claim 3, characterized in that: When the filler is polyurethane, the corresponding thickness of the stirring blade (294) is 16 mm to 18 mm; When the filler is volcanic rock, the corresponding thickness of the stirring blade (294) is 22 mm to 25 mm; When the filler is ceramsite, the corresponding thickness of the stirring blade (294) is 18 mm to 22 mm; When the filler is a hollow ball, the corresponding thickness of the stirring blade (294) is 18 mm to 20 mm; When the filler is bamboo charcoal, the corresponding thickness of the stirring blade (294) is 16 mm to 20 mm.

5. The biofilter according to claim 4, characterized in that: A movable scraper (2234) is also provided above the first movable bacterial biofilm filling layer (2231); the length of the scraper (2234) is 1m to 3m; the height between the bottom and the top of the scraper (2234) is 15cm to 25cm; the angle between the scraper (2234) and the horizontal plane is 60° to 90°; the material of the scraper (2234) is one of 304 stainless steel, galvanized steel, and fiberglass; The top of the second box body (2) is also provided with an exhaust gas outlet (23); the exhaust gas outlet (23) is in communication with the second spray layer (224); the exhaust gas outlet (23) is connected to a second gas differential pressure gauge (24); A second spray assembly is provided in the second spray layer (224); the second spray assembly comprises a second spray pipe (2241), and the second spray pipe (2241) is fixed to the top of the second box (2); a plurality of second spray ports (2242) are also provided below the second spray pipe (2241); a temperature sensor (2243) is also connected to the second spray layer (224); The inlet end of the second spray pipe (2241) is connected to a second spray liquid storage tank (25); the second spray liquid storage tank (25) is in communication with the second water storage tank (221); a second spray liquid delivery pump (26) is provided on the pipeline between the second spray pipe (2241) and the second spray liquid storage tank (25); and the second spray liquid storage tank (25) is also connected to a strain storage box (27) and a liquid level meter (28).

6. The biofilter according to claim 5, characterized in that: It also includes a first box (1) and an intelligent control box (3); the first box (1) includes a first air inlet chamber (11) and a first spray chamber (12); the first spray chamber (12) is configured from bottom to top as a first water storage tank (121), a first air distribution layer (122), a first filler layer (123), and a first spray layer (124); An exhaust gas inlet (13) is provided at the top of the first box body (1); the exhaust gas inlet (13) is in communication with the first air inlet chamber (11); and a first gas differential pressure gauge (14) is connected to the exhaust gas inlet (13); The first air inlet cavity (11) is in communication with the first spray cavity (12) via the first air distribution layer (122); the first spray cavity (12) is in communication with the second air inlet cavity (21) via the first spray layer (124); The first filler layer (123) comprises at least two layers of grid plates, the grid plates are provided with fillers, the fillers are hollow balls; the material of the hollow balls is PP; the thickness of the fillers on the grid plates is 0.5m to 1.0m; gaps are provided between the grid plates; the height of the gaps is 10cm to 15cm; A first spray assembly is provided in the first spray layer (124); the first spray assembly comprises a first spray pipe (1241), the first spray pipe (1241) is fixed to the top of the first box (1); a plurality of first spray ports (1242) are further provided below the first spray pipe (1241); The inlet end of the first spray pipe (1241) is connected to a first spray liquid storage pool (15); the first spray liquid storage pool (15) is in communication with the first water storage pool (121); a first spray liquid delivery pump (16) is provided on the pipeline between the first spray pipe (1241) and the first spray liquid storage pool (15); the first spray liquid storage pool (15) is also connected to a micro-nano bubble generator (17); The intelligent control box (3) is electrically connected to the first gas differential pressure gauge (14), the first spray liquid delivery pump (16), the second gas differential pressure gauge (24), the second spray liquid delivery pump (26), and the motor (295), respectively; the intelligent control box (3) is a PLC control device or a DCS control device.

7. A method for treating VOCs and malodorous gases, characterized in that: The biofilter described in claim 6 is used to treat VOCs and malodorous gases.

8. The method according to claim 7, characterized in that When using a biofilter to treat VOCs and malodorous gases, the following steps are included: S1, introducing VOCs and malodorous gases into the first housing (1) from the exhaust gas inlet (13), turning on the first spray liquid delivery pump (16) and the micro-nano bubble generator (17), and spraying micro-nano bubble water onto the first filler layer (123) to wash the VOCs and malodorous gases; S2, the VOCs and malodorous gases washed in step S1 are introduced into the second box (2) through the second air inlet cavity (21), the second spray liquid delivery pump (26) is turned on, and the mixed bacterial liquid is sprayed onto the second filler layer (223) to wash the VOCs and malodorous gases, thereby completing the purification treatment of the VOCs and malodorous gases.

9. The method according to claim 8, characterized in that In step S2, during the leaching process, the residence time of the VOCs and malodorous gases in the second packing layer (223) is 10s to 60s; the leaching process also includes the following processing: using the first gas differential pressure gauge (14) and the second gas differential pressure gauge (24) to detect the pressure loss at both ends of the exhaust gas inlet and outlet of the biofilter, and obtaining the pressure loss value during the operation process; when the pressure loss value during the operation process exceeds 15% to 30% of the initial design pressure loss value, stop the air intake and leaching, start the stirring device (29) to stir the packing in the second packing layer (223), and start The process includes: inletting air and eluting until the pressure difference measured by the first gas differential pressure gauge (14) and the second gas differential pressure gauge (24) is 60% to 100% of the designed pressure difference and remains stable for 0.05 h to 1 h. Otherwise, the inletting air and eluting are stopped, and the filler in the second filler layer (223) is continuously stirred. The stirring time for a single stirring process is 5 min to 25 min. During the stirring process, the speed of the stirring device (29) is controlled to be 15 rpm to 30 rpm. After the stirring process is completed, the following process is further included: adding water to the second water storage tank (22 1) adding spray liquid to the second spray liquid storage tank (25), adding solid bacterial agent in the bacterial strain storage box (27), mixing with the spray liquid to form a mixed bacterial liquid, starting the second spray liquid delivery pump (26), spraying the mixed bacterial liquid onto the second filler layer (223) to perform a taming treatment on the bacterial strain until a biofilm is formed in the filler; during the taming treatment, spraying is performed for 2 to 6 hours every day; before starting the rinsing, the following treatment is also included: adding spray liquid to the second water storage tank (221) and the second spray liquid storage tank (25), adding solid bacterial agent in the bacterial strain storage box (27), The solid bacterial agent is mixed with the spray liquid to form a mixed bacterial liquid, and the second spray liquid delivery pump (26) is turned on to spray the mixed bacterial liquid onto the second filler layer (223) to activate the bacteria until a biofilm is formed in the filler. VOCs and malodorous gases are introduced into the second box (2) by intermittent air intake to cultivate the biofilm. During the activation process, spraying is performed for 20 minutes to 40 minutes every day for 2 to 4 days. During the cultivation process, VOCs and malodorous gases are introduced into the second box (2) from 7:00 to 19:00 every day.

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