A biochemical filtration tank and its deodorization method

Abstract

This invention relates to a biochemical filtration tank, comprising a tank body, a first spray pipe, and a second spray pipe. An internal partition extending along the height of the tank body divides the tank body into a pre-washing chamber, a biofiltration chamber, and an exhaust chamber. The pre-washing chamber is filled with a first chemical packing material. The biofiltration chamber is filled with a second chemical packing material, the surface of which is covered with a large number of microbial communities. Multiple first and second support piers are located at the bottom of the exhaust chamber, with a grid mesh installed on the first support piers. In this invention, odorous gas first enters the pre-washing chamber through an inlet pipe, is humidified by the first spray pipe, and undergoes pretreatment of absorption, dust removal, and humidification of the odorous gas within the first chemical packing area. The odorous gas then enters the biofiltration chamber, where, upon passing through the second chemical packing material, pollutants are transferred from the gas phase to the biofilm surface. The odorous components entering the biofilm are removed through oxidative decomposition by microorganisms, thereby achieving deodorization.

Description

Technical Field

[0001] This invention relates to a biochemical filtration tank and its deodorization method. Background Technology

[0002] The odor of garbage is produced by the decomposition of organic components by bacteria. Household waste consists of 75-80% organic matter, mainly including fruit peels, vegetable leaves and stalks, leftover food, poultry, animal and fish skin, fur, viscera, fat, feces, scraps / blood, leaves, waste paper, flowers, and animal carcasses, as well as a certain amount of moisture. During natural digestion, through aerobic / anaerobic fermentation, foul odors are produced, especially in hot weather when fermentation accelerates and the odor becomes more severe. The odor of household waste includes ammonia, hydrogen sulfide, organic amines, organic sulfur compounds, and volatile fatty acids.

[0003] Currently, methods for treating odorous gases generated by wastewater treatment plants mainly include biological methods, activated carbon adsorption, chemical scrubbing, and plasma methods. Existing biological deodorization devices typically include biological scrubbing towers, biological filter towers, and biological trickling filters; however, they generally have the following drawbacks:

[0004] 1) Uneven air distribution can easily lead to short-flow dead zones;

[0005] 2) The pollutant removal load varies greatly along the packing layer, making it prone to caking;

[0006] 3) Poor gas-liquid mass transfer effect.

[0007] In summary, existing biological deodorization devices suffer from drawbacks such as uneven gas distribution, significant differences in pollutant removal load among the packing layers, susceptibility to caking, and low gas-liquid mass transfer efficiency. These limitations result in reduced effective volume, lower processing load, and poor treatment performance, making it difficult to meet increasingly stringent deodorization requirements. Therefore, this paper proposes a biochemical filtration tank and its deodorization method to address these issues. Summary of the Invention

[0008] This invention provides a biochemical filtration tank and its deodorization method to solve the technical problems of existing biological deodorization devices, namely: 1. uneven gas distribution, which easily leads to short-flow dead zones; 2. large differences in pollutant removal load along the packing layer, which easily leads to caking; and 3. poor gas-liquid mass transfer effect.

[0009] To solve the above problems, the biochemical filtration tank and its deodorization method provided by the present invention adopt the following technical solution: including:

[0010] The pool body has internal partitions extending along its height, which divide the pool body into a pre-washing chamber, a biological filter chamber, and a discharge chamber. The pre-washing chamber and the biological filter chamber are interconnected through the discharge chamber.

[0011] The pre-washing chamber is filled with a first chemical filler;

[0012] The biofilter chamber is filled with a second chemical packing material, and a large number of microbial communities are provided on the surface of the second chemical packing material.

[0013] The bottom of the discharge chamber is provided with a plurality of first support blocks and second support blocks, and the first support blocks are equipped with grid mesh for supporting the first chemical packing and the second chemical packing.

[0014] The first spray pipe is installed in the pre-washing chamber. An air inlet pipe is installed on the first spray pipe so that the negative pressure generated by the first spray pipe during the liquid inlet process drives the odor in the air inlet pipe to move simultaneously. A mixing unit is installed inside the first spray pipe so that the liquid and gas are fully mixed.

[0015] The second spray pipe extends along the length of the pool body and is installed inside the biological filter chamber, and is located above the second chemical packing material.

[0016] Furthermore, the pool body is made of 50mm fiberglass composite panel, and the interior of the pool body is filled with rock wool insulation material.

[0017] Furthermore, a pool cover is provided on the top of the pool body.

[0018] Furthermore, the first chemical packing material is a multi-faceted hollow sphere packing material with a height of 1.6m and a volumetric surface area of ​​not less than 380m². 2 / m 3 .

[0019] Furthermore, the mixing unit includes a fixed tube, inside which are arranged two perforated plates, and between the two perforated plates is a rotating shaft. The upper end of the rotating shaft passes through the perforated plates and is provided with a first fan, and between the two perforated plates is a second fan connected to the rotating shaft.

[0020] Furthermore, the blades of the second fan are oriented in the opposite direction to the blades of the first fan.

[0021] Furthermore, the second chemical packing material is bamboo charcoal packing material.

[0022] Furthermore, the second support pier is longer than the first support pier, and the second support pier extends into the biofilter cavity.

[0023] A method for deodorizing a biological filtration tank includes the following steps:

[0024] Step A: Pretreatment: The odorous gas enters the pre-washing chamber through the inlet pipe, and at the same time, it comes into contact with and merges with the odorous gas through the first spray pipe, and then enters the first chemical packing to remove the liquid in the odorous gas and carry out oxidation treatment.

[0025] Step B: Purification treatment: The gas in the pre-treated odorous gas moves downward through the pre-wash chamber and enters the biofilter chamber through the grid in the discharge chamber, while the odorous liquid enters the discharge chamber through the grid.

[0026] Step C: Microbial treatment: The odorous gas reacts with the microorganisms in the second chemical packing material, allowing the microorganisms to reach a suitable survival temperature. The odorous gas stays in the biofilter chamber for a period of time from the pre-wash chamber. At the same time, different microorganisms are used to target different types of odors according to their different components.

[0027] Step F: The odorous gas treated in the biological filter chamber meets the emission standards and is discharged through the exhaust pipe.

[0028] The beneficial effects are as follows: The odorous gas first enters the pre-washing chamber through the inlet pipe, is humidified by the first spray pipe, and undergoes pre-treatment of absorption, dust removal, and humidification within the first chemical packing layer. The remaining odorous gas then enters the biofilter zone. As it passes through the second chemical packing layer, pollutants are transferred from the gas phase to the biofilm surface. The odorous components entering the biofilm are removed through oxidative decomposition by microorganisms. The microorganisms use the absorbed odorous components as an energy source for further reproduction, thereby achieving the purpose of deodorization. Attached Figure Description

[0029] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the invention are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts, wherein:

[0030] Figure 1 This is an internal schematic diagram of the pool structure of the present invention;

[0031] Figure 2 This is a three-dimensional schematic diagram of the pool structure of the present invention;

[0032] Figure 3 This is a cross-sectional schematic diagram of the first spray pipe structure of the present invention;

[0033] Figure 4 This is a cross-sectional schematic diagram of the hybrid unit structure of the present invention.

[0034] In the diagram: 1. Pool body; 2. Baffle plate; 3. First spray pipe; 4. Air inlet pipe; 5. Second spray pipe; 6. Exhaust pipe; 7. Drain pipe; 8. Pool cover; 11. Pre-wash chamber; 12. Biological filter chamber; 13. Discharge chamber; 111. First chemical packing material; 121. Second chemical packing material; 131. First support pier; 132. Second support pier; 133. Grille; 31. Mixing unit; 301. Fixed pipe; 302. Perforated plate; 304. Rotating shaft; 305. First fan; 306. Second fan. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Those skilled in the art should understand that the embodiments described below are only some, not all, of the embodiments disclosed. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] Various non-limiting embodiments of the present invention are described in detail below. Any number of elements in the accompanying drawings is for illustrative purposes only and not for limitation, and any naming is for distinction only and has no limiting meaning.

[0037] The principles and spirit of the present invention will be explained in detail below with reference to several representative embodiments.

[0038] like Figure 1 and Figure 2 As shown, the biochemical filtration tank provided by the present invention includes a tank body 1, which is a 50mm fiberglass composite panel. The tank body 1 is filled with rock wool insulation material, which can give the tank body 1 a good heat preservation effect and maintain the stability of the internal temperature of the biofiltration tank in winter. The top of the tank body 1 is provided with a tank cover 8, which can keep the temperature of the exhaust gas inside the structure and the heat generated by the metabolism of microorganisms above 15°C, so as to maintain the normal operation of microorganisms in winter. The tank body 1 is connected to a partition 2 extending along the height direction of the tank body 1, so that the top and sides of the partition 2 are connected to the corresponding inner walls of the tank body 1. The tank body 1 is divided into a pre-washing chamber 11, a biofiltration chamber 12 and an exhaust chamber 13 through the partition 2. The pre-washing chamber 11 and the biofiltration chamber 12 are interconnected through the exhaust chamber 13.

[0039] like Figure 1 and Figure 2 As shown, the top of the pre-washing chamber 11 is connected to the first spray pipe 3 and the air inlet pipe 4. The pre-washing chamber 11 is filled with a first chemical packing material 111, which is a multi-faceted hollow spherical packing material with a height of 1.6m. The volumetric surface area (i.e., the surface area to volume ratio) of the packing material is not less than 380m³. 2 / m 3With appropriate porosity and low pressure loss, the odor enters the pre-washing chamber 11 and passes through the first chemical packing 111, which can complete the absorption of odor water, dust removal and humidification pretreatment.

[0040] like Figure 3 and Figure 4 As shown, the air inlet pipe 4 is connected to and communicates with the first spray pipe 3, so that the negative pressure generated by the first spray pipe 3 during the liquid inlet process drives the odor in the air inlet pipe 4 to move simultaneously. The first spray pipe 3 is provided with a mixing unit 31, so that the liquid and gas are stirred and mixed when passing through the mixing unit 31 at the same time. The mixing unit 31 includes a fixed pipe 301, and two sluice plates 302 are provided inside the fixed pipe 301. A rotating shaft 304 is provided between the two sluice plates 302. The upper end of the rotating shaft 304 passes through the sluice plates 302 and is provided with a first fan 305. A second fan 306 is provided between the two sluice plates 302 and connected to the rotating shaft 304. Specifically, the first fan 305 rotates under the impact of the liquid, causing the liquid to flow downward. At the same time, the first fan 305 drives the second fan 306 through the rotating shaft 304. Since the blades of the second fan 306 are in the opposite direction to the blades of the first fan 305, the speed of the liquid and gas flowing downward is slowed down by the action of the second fan 306 and the baffle plate 302. Then, the first fan 305 and the second fan 306 make the liquid and gas fully mixed.

[0041] like Figure 1 and Figure 2 As shown, the top of the biological filter chamber 12 is connected to an exhaust pipe 6. A second spray pipe 5 extending along the length of the tank body 1 is provided on the side of the biological filter chamber 12 away from the partition 2. To prevent the moisture of the packing material from decreasing due to continuous operation at a high temperature of 35-40℃, multiple nozzles are provided below the second spray pipe 5. The biological filter chamber 12 is filled with a second chemical packing material 121, which is located below the second spray pipe 5. The second chemical packing material 121 is bamboo charcoal packing material, which has a large specific surface area and is resistant to acid and alkali corrosion. The second chemical packing material 121 has been strictly screened and rationally distributed. A large number of microbial communities are provided on the surface of the second chemical packing material 121. These communities are the dominant species. After domestication, they are better at removing odorous substances than general biological deodorizing bacteria. After the waste gas is treated by the microorganisms on the second chemical packing material 121, the final emitted gas meets the emission standards and does not affect the surrounding environment. The second chemical packing material 121 has the characteristics of being suitable for microbial growth, good water retention, not easy to rot, and easy to form biofilms. No nutrients for the growth and reproduction of microorganisms need to be added to the biological filter during normal operation.

[0042] like Figure 1 and Figure 2As shown, the bottom of the discharge chamber 13 is provided with multiple first support blocks 131 and second support blocks 132. The length of the second support blocks 132 is greater than that of the first support blocks 131. The second support blocks 132 extend into the biological filter chamber 12. A grid 133 for supporting the first chemical packing 111 and the second chemical packing 121 is installed on the first support blocks 131. The grid 133 is in contact with the partition 2. The first support blocks 131 enable the discharge chamber 13 to have a drainage space. The arrangement between the first support blocks 131 and the second chemical packing 121 can support and fix the grid 133. A drain pipe 7 connected to the pool body 1 is provided at one end of the discharge chamber 13.

[0043] A method for deodorizing a biological filtration tank includes the following steps:

[0044] Step A: Pretreatment: The odorous gas enters the pre-washing chamber 11 through the air inlet pipe 4, and at the same time, it comes into contact with and merges with the odorous gas through the first spray pipe 3, and enters the first chemical packing 111 to remove the liquid in the odorous gas and carry out oxidation treatment at the same time.

[0045] Step B: Purification treatment: The gas in the pre-treated odorous gas moves downward through the pre-wash chamber 11 and enters the biofilter chamber 12 through the grid 133 in the discharge chamber 13. The odorous liquid enters the discharge chamber 13 through the grid 133.

[0046] Step C: Microbial treatment: The odorous gas reacts with the microorganisms in the second chemical packing 121. The survival temperature of the microorganisms is about 25℃. The odorous gas stays in the pre-wash chamber 11 and the biofilter chamber 12 for 15 seconds. The odorous gas is a sulfur-containing series that is oxidized and decomposed into S, SO32-, and SO42-. The microorganisms are sulfur oxidizing bacteria. The role of sulfur oxidizing bacteria is to remove sulfur compounds such as hydrogen sulfide, methanethiol, and methyl sulfur.

[0047] If the odor is nitrogen-containing, it will be oxidized and decomposed into NH4+, NO2-, and NO3-. The bacteria are either digestive bacteria or nitrogen-oxidizing bacteria. The role of digestive bacteria or nitrogen-oxidizing bacteria is to remove ammonia from the odor components.

[0048] When the odorous gas is H2S, the bacteria are autotrophic sulfur oxidizing bacteria. Under certain conditions, autotrophic sulfur oxidizing bacteria will oxidize H2S into sulfate.

[0049] When the odorous gas is organic sulfur such as methanethiol, the bacteria are heterotrophic microorganisms. The heterotrophic microorganisms need to convert the organic sulfur into H2S, and then the H2S is oxidized into sulfate by autotrophic microorganisms.

[0050] H₂S + O₂ + autotrophic sulfur-oxidizing bacteria + CO₂ → synthesis of cellular material + SO₄²⁻ + H₂O

[0051] CH3SH→CH4+H2S→CO2+H2O+SO42-

[0052] When the malodorous gas is NH3, ammonia first reacts with water to form ammonia water. The bacteria are nitrite bacteria and nitrate bacteria. Nitrification by nitrite bacteria and nitrate bacteria converts nitrate into nitrate. Under facultative anaerobic conditions, nitrate-reducing bacteria reduce nitrate into nitrogen gas.

[0053] Nitrification: NH3 + O2 → HNO2 + H2O

[0054] HNO₂ + O₂ → HNO₃ + H₂O

[0055] Denitrification: HNO3 → HNO2 → HNO → N2O → N2

[0056] The pH of the entire system should be maintained between 5 and 8. If the pH value drops, it indicates that the normal flora has been destroyed and the pH needs to be adjusted to neutral.

[0057] Step D: Spray treatment: After the odor components are oxidized and decomposed, H2SO4 (weak sulfuric acid) and HNO3 (weak nitric acid) are generated. These acids are washed away by spraying water through the second spray pipe 5, and the sloughed biofilm is discharged in time to maintain a good environment suitable for microbial growth.

[0058] The reaction of microorganisms when they decompose the main malodorous components:

[0059] Hydrogen sulfide: H2S + 2O2 → H2SO4

[0060] Methanethiol: 2CH3SH + 7O2 → 2H2SO4 + 2CO2 + 2H2O

[0061] Methylated sulfur: (CH3)2S + 5O2 → H2SO4 + 2CO2 + 2H2O

[0062] Dimethyl disulfide: 2(CH3)2S + 13O2 → 4H2SO4 + 4CO2 + 2H2O

[0063] Ammonia: NH3 + 2O2 → NHO3 + H2O

[0064] Trimethylamine: 2(CH3)3N+13O2→2HNO3+6CO2+8H2O

[0065] Step F: The odorous gas treated in the biological filter chamber 12 meets the emission standards and is discharged through the exhaust pipe 6.

[0066] Based on the above description in this specification, those skilled in the art will also understand that the following terms, such as "upper," "lower," "front," "rear," "left," "right," "width," "horizontal," "top," "bottom," "inner," and "outer," which indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings of this specification. They are only for the purpose of facilitating the explanation of the present invention and simplifying the description, and do not explicitly or implicitly suggest that the device or element involved must have the specific orientation, or be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms should not be understood or interpreted as limitations on the present invention.

[0067] In addition, in the description of this specification, "multiple" means at least two, such as two, three or more, etc., unless otherwise expressly and specifically defined.

Claims

1. A biochemical filter tank, characterized by, Include: The pool body (1), the inside of the pool body (1) is connected with the partition (2) extending along the height direction of the pool body (1), the pool body (1) is divided into pre-washing cavity (11), biological filter cavity (12) and discharge cavity (13) through the partition (2), the pre-washing cavity (11) and biological filter cavity (12) are communicated with each other through the discharge cavity (13); The first chemical filler (111) is filled in the pre-washing cavity (11); The second chemical filler (121) is filled in the biological filter cavity (12), and a large number of microbial flora are arranged on the second chemical filler (121); The bottom of the discharge cavity (13) is provided with a plurality of first support piers (131) and second support piers (132), the first support piers (131) are provided with a grid net (133) for bearing the first chemical filler (111) and the second chemical filler (121); The first spray pipe (3) is arranged in the pre-washing cavity (11), the air inlet pipe (4) is arranged on the first spray pipe (3), so that the negative pressure generated by the first spray pipe (3) during liquid inlet drives the odor in the air inlet pipe (4) to move, and the mixing unit (31) is arranged in the first spray pipe (3), so that the liquid and the gas are fully mixed; The second spray pipe (5) is arranged in the biological filter cavity (12) along the length direction of the pool body (1) and above the second chemical filler (121); The mixing unit (31) comprises a fixed pipe (301), two leakage plates (302) are arranged in the fixed pipe (301), a rotating shaft (304) is arranged between the two leakage plates (302), the upper end of the rotating shaft (304) penetrates through the leakage plate (302) and is provided with a first fan (305), and a second fan (306) connected to the rotating shaft (304) is arranged between the two leakage plates (302).

2. The biochemical filter tank according to claim 1, characterized in that: The pool body (1) is a 50mm glass steel composite plate, and the inside of the pool body (1) is filled with rock wool thermal insulation material.

3. The biochemical filter tank according to claim 1, characterized in that: The top of the pool body (1) is provided with a pool cover (8).

4. The biochemical filter tank according to claim 1, characterized in that: The first chemical packing (111) is a multi-faceted hollow sphere packing, the packing height is 1.6m, the volume specific surface area of the packing is not less than 380m 2 / m 3 .

5. The biochemical filter tank according to claim 1, characterized in that: The blades of the second fan (306) are opposite to the blades of the first fan (305).

6. The biochemical filter tank according to claim 1, characterized in that: The second chemical filler (121) is a bamboo charcoal filler.

7. The biochemical filter tank according to claim 1, characterized in that: The length of the second support pier (132) is greater than that of the first support pier (131), and the second support pier (132) extends into the biological filter cavity (12).

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