A drying waste gas treatment system

Abstract

The present invention relates to the technical field of waste gas treatment systems, and in particular to a waste gas treatment system for drying waste embryos. The waste gas treatment system is connected to the exhaust port of a drying room for drying biological waste embryos, and includes a preheater, an SCR reactor, a spray tower, a primary activated carbon adsorber, a secondary activated carbon adsorber, a fan and an exhaust pipe connected in sequence: the preheater is used to heat the dried waste gas; the SCR reactor is used to denitrate the preheated gas; the spray tower is provided with a spray liquid for removing pollutants in the waste gas, and the primary activated carbon adsorber and the secondary activated carbon adsorber are used to adsorb organic components in the waste gas. The present invention removes nitrogen oxides in the waste gas from the drying of biological waste embryos through an SCR reactor, then removes pollutants in the waste gas through a spray tower, and finally adsorbs organic components in the waste gas through an activated carbon adsorber, so that the waste gas is purified and then discharged, meeting the emission standards.

Description

Technical Field

[0001] The invention relates to the technical field of waste gas treatment, and in particular to a drying waste gas treatment system. Background Art

[0002] In the prior art, the waste gas generated by waste eggs and other biological embryos after drying is generally discharged directly into the air. However, the emission concentration of NOx in the waste gas fluctuates greatly and there is a risk of exceeding the standard. At the same time, the foul odor of the exhaust gas affects the surrounding atmospheric environment. Summary of the invention

[0003] In order to solve the problem in the prior art that waste gas generated by bio-based embryos after drying is directly discharged into the air, resulting in excessive concentration of nitrogen oxides and the risk of generating foul odor, the present invention provides a drying waste gas treatment system.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A drying waste gas treatment system, the waste gas treatment system is connected to the exhaust port of a drying room used for drying bio-based embryos, and comprises a preheater, an SCR reactor, a spray tower, a primary activated carbon adsorber, a secondary activated carbon adsorber, a fan and an exhaust pipe which are connected in sequence: the preheater is used to heat the drying waste gas; the SCR reactor is used to denitrate the preheated gas; the spray tower is provided with a spray liquid for removing pollutants in the waste gas, and the primary activated carbon adsorber and the secondary activated carbon adsorber are used to adsorb organic components in the waste gas.

[0006] Furthermore, the exhaust gas in the spray tower flows from bottom to top.

[0007] Furthermore, the inlet of the spray tower is connected to an induced draft fan.

[0008] Furthermore, an alkali liquid tank is provided below the spray tower, the alkali liquid tank is connected to a circulation pipeline, a circulation pump is provided on the circulation pipeline, the circulation pipeline is provided with several branches, atomizing nozzles are provided on the branches, and a hollow ball filler is provided below the atomizing nozzle in the spray tower.

[0009] Furthermore, the SCR reactor is connected to the spray tower through a long pipeline. The long pipeline connection can, on the one hand, place the subsequent equipment of the SCR reactor in other locations to reduce the occupied area of ​​the equipment, and on the other hand, the gas discharged from the SCR can be fully cooled during the transportation process of the long pipeline to prevent the gas temperature entering the spray tower from being too high.

[0010] Furthermore, the preheater and SCR reactor are arranged next to the drying room, and the spray tower, the first-level activated carbon adsorber, the second-level activated carbon adsorber, the fan and the exhaust pipe are arranged on the roof of the factory building, which does not occupy the ground space and saves space. The exhaust pipe can be arranged along the wall for easy installation.

[0011] Furthermore, the primary activated carbon adsorber and the secondary activated carbon adsorber are made of water-resistant honeycomb carbon.

[0012] Beneficial effects: The present invention removes nitrogen oxides in the drying waste gas of the biological waste substrate through an SCR reactor, then removes pollutants in the waste gas through a spray tower, and finally absorbs odors in the waste gas through an activated carbon adsorber, so that the waste gas is purified and then discharged in compliance with emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0014] Figure 1 It is a processing process flow chart of the drying waste gas treatment system of the present invention;

[0015] Figure 2 It is an overall top view schematic diagram of the drying waste gas treatment system of the present invention;

[0016] Figure 3 It is a top view schematic diagram of the preheater and SCR reactor located on the first floor;

[0017] Figure 4 It is a top view schematic diagram of the spray tower, primary activated carbon adsorber, secondary activated carbon adsorber, fan and exhaust pipe located on the second floor;

[0018] Figure 5 This is a schematic diagram of the structure of the spray tower.

[0019] 1. Drying room, 2. Preheater, 3. SCR reactor, 4. Spray tower, 41. Alkali liquid tank, 42. Circulation pump, 43. Atomizing nozzle, 44. Hollow ball filler, 5. Primary activated carbon adsorber, 6. Secondary activated carbon adsorber, 7. Fan, 8. Exhaust pipe, 9. Draft fan, DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. 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.

[0021] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0022] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0023] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0024] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0025] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0026] like Figures 1 to 5 The present invention provides a drying waste gas treatment system, which is connected to the exhaust port of a drying room 1 for drying bio-based embryos, and includes a preheater 2, an SCR reactor 3, a spray tower 4, a primary activated carbon adsorber 5, a secondary activated carbon adsorber 6, a fan 7 and an exhaust pipe 8 connected in sequence: the preheater 2 is used to heat the drying waste gas; the SCR reactor 3 is used to denitrify the preheated gas; the spray tower 4 is provided with a spray liquid for removing pollutants in the waste gas, and the primary activated carbon adsorber 5 and the secondary activated carbon adsorber 6 are used to adsorb organic components in the waste gas.

[0027] The reducing agent used in the SCR denitration process is ammonia, and the most commonly used are ammonia water and urea solution. This project uses 32.5% urea, which is the SCR denitration liquid for diesel vehicles. It is cold-resistant and does not freeze at minus 11 degrees. It is easy to replenish and can be used directly without compounding. A dual-fluid spray gun is used, and the urea atomization particle size is less than 30μm SMD, ensuring that the urea aqueous solution is fully hydrolyzed and pyrolyzed at a flue gas temperature below 200℃, improving the utilization rate of urea and avoiding crystallization. The spray gun atomization diffusion angle is only 15°. Through a long fog distance, full evaporation is achieved, avoiding the phenomenon of crystallization caused by local flue gas cooling caused by spraying within a short fog distance.

[0028] The waste gas in the spray tower 4 flows from bottom to top. The inlet of the spray tower 4 is connected to an induced draft fan 9. An alkali liquid tank 41 is provided below the spray tower 4, and the alkali liquid tank 41 is connected to a circulation pipeline, and a circulation pump 42 is provided on the circulation pipeline, and a plurality of branches are provided on the circulation pipeline, and atomizing nozzles 43 are provided on the branches. A hollow ball filler 44 is provided below the atomizing nozzle 43 in the spray tower 4. The pollutants are sucked into the suction pipe by the suction force of the induced draft fan 9 and enter the lower part of the spray tower 4; the airflow in the tower flows tangentially along the spray tower 4 from bottom to top, and is sprayed by the first-stage absorption liquid in a mist state, at which time a part of the pollutants is absorbed; the pollutants that are not absorbed are dispersed and condensed upward by the hollow ball filler 44, and then sprayed and absorbed by the second-stage absorption liquid, and the tail gas is discharged after passing through the wind shielding and demisting device. The absorption liquid is recycled and enters the umbrella-shaped valve atomizing nozzle 43 with high pressure from the circulation pump 42 to spray downwards. The pollutants are moved upwards, and the gas and liquid phases fully collide and contact. The pollutants are absorbed by the absorption liquid to achieve the purpose of removing the pollutants.

[0029] The SCR reactor 3 is connected to the spray tower 4 through a long pipeline. The preheater 2 and the SCR reactor 3 are arranged next to the drying room 1, and the spray tower 4, the primary activated carbon adsorber 5, the secondary activated carbon adsorber 6, the fan 7 and the exhaust pipe 8 are arranged on the roof of the plant building.

[0030] The primary activated carbon adsorber 5 and the secondary activated carbon adsorber 6 are made of water-resistant honeycomb carbon. Activated carbon is a highly efficient adsorption material, which has a high adsorption effect on toxic and harmful gases, fast adsorption and desorption speed, and is resistant to acid and alkali corrosion. It has a significant purification effect on organic waste gases containing benzene, sulfur dioxide, carbon monoxide, nitrogen oxides, hydrogen sulfide, petroleum gas, odor, etc., and its purification efficiency reaches more than 95%. This project conservatively estimates its adsorption efficiency to be 80%. The activated carbon adsorber is divided into an air inlet section, a carbon filter section, and an air outlet section, and the filter section is filled with honeycomb activated carbon. The organic waste gas enters the box from the air inlet, and the adsorption capacity of the honeycomb activated carbon is used to adsorb and remove pollutants in the waste gas, and the purified exhaust gas is discharged into the atmosphere by the ventilator.

[0031] Working principle:

[0032] The drying waste gas is first heated to about 160°C by a preheater, and then introduced to the SCR reactor 3 (SCR denitration system). Before entering the SCR reactor 3, a urea solution atomization injection system is set up, and a mixing device is arranged to ensure that the flue gas and the atomized urea are fully mixed before entering the SCR reactor 3. Under the action of the catalyst, a selective catalytic reduction reaction occurs, and NOx is reduced to N2 and H2O before entering the spray tower 4. The waste gas from the spray tower 4 flows tangentially from bottom to top along the waste gas purification tower, collides with and fully contacts the spray liquid from top to bottom, and the gas and liquid react and absorb fully, and the pollutants in the waste gas are removed before entering the primary activated carbon adsorber 5. The waste gas is reasonably distributed so that it evenly passes through the flow section of the activated carbon layer in the fixed adsorption bed. During a certain residence time, physical adsorption (also known as van der Waals adsorption) occurs due to the mutual attraction between the surface of the activated carbon and the organic waste gas molecules. Its characteristics are: the adsorbate (organic waste gas) and the adsorbent (activated carbon) do not react with each other, the process is fast, the properties of the adsorbent itself do not change during the adsorption process, and the adsorption process is reversible; the organic components in the waste gas are adsorbed on the surface of the activated carbon, so that the waste gas is purified. The purified waste gas is further adsorbed by the secondary activated carbon adsorber 6 and discharged through the exhaust pipe 8.

[0033] The drying waste gas treatment system of the present invention can be used not only for the treatment of drying waste gas from waste egg and chicken embryos, but also for the treatment of drying waste gas from other bio-based embryos.

[0034] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A drying waste gas treatment system, characterized in that: The waste gas treatment system is connected to the exhaust port of a drying room (1) for drying bio-based embryos, and comprises a preheater (2), an SCR reactor (3), a spray tower (4), a primary activated carbon adsorber (5), a secondary activated carbon adsorber (6), a fan (7) and an exhaust pipe (8) which are connected in sequence: the preheater (2) is used to heat the dried waste gas; the SCR reactor (3) is used to denitrate the preheated gas; the spray tower (4) is provided with a spray liquid for removing pollutants in the waste gas; the primary activated carbon adsorber (5) and the secondary activated carbon adsorber (6) are used to adsorb organic components in the waste gas.

2. A drying waste gas treatment system according to claim 1, characterized in that: The waste gas in the spray tower (4) flows from bottom to top.

3. A drying waste gas treatment system according to claim 2, characterized in that: The inlet of the spray tower (4) is connected to an induced draft fan (9).

4. A drying waste gas treatment system according to claim 2, characterized in that: An alkali liquid tank (41) is provided below the spray tower (4), the alkali liquid tank (41) is connected to a circulation pipeline, a circulation pump (42) is provided on the circulation pipeline, the circulation pipeline is provided with a plurality of branches, atomizing nozzles (43) are provided on the branches, and a hollow ball filler (44) is provided below the atomizing nozzle (43) in the spray tower (4).

5. A drying waste gas treatment system according to claim 1, characterized in that: The SCR reactor (3) is connected to the spray tower (4) via a long pipeline.

6. A drying waste gas treatment system according to claim 1, characterized in that: The preheater (2) and the SCR reactor (3) are arranged next to the drying room (1), and the spray tower (4), the primary activated carbon adsorber (5), the secondary activated carbon adsorber (6), the fan (7) and the exhaust pipe (8) are arranged on the roof of the factory building.

7. A drying waste gas treatment system according to claim 1, characterized in that: The primary activated carbon adsorber (5) and the secondary activated carbon adsorber (6) are made of water-resistant honeycomb carbon.

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