Efficient and low-energy-consumption waste gas treatment method

Abstract

The invention discloses a high-efficiency and low-energy-consumption waste gas treatment method, which comprises the processes of waste gas collection, pretreatment, waste gas oxidation and waste gas washing treatment, and is characterized in that an electrodeless ultraviolet technology and a supergravity dust removal technology are combined, water is used as a washing medium, and waste gas oxidized by microwave electrodeless ultraviolet equipment is washed and absorbed; various waste gases can be effectively treated with lower cost and operation cost, and pollution components in the waste gases are transferred into sewage.

Description

Technical Field

[0001] The invention relates to the field of waste treatment, and in particular to a high-efficiency, low-energy consumption waste gas treatment method. Background Art

[0002] Waste gas pollution components include inorganic waste gas, organic waste gas and particulate matter. Inorganic waste gas includes: sulfur oxides, nitrogen oxides, ammonia, hydrogen sulfide, ozone, etc.; organic waste gas mainly includes VOCs. In traditional processes, there are also processes that use water absorption to absorb VOCs, such as water curtain method, cyclone tower, spray tower. The problem is that the contact area between water and waste gas is small, and the mass transfer is insufficient, resulting in poor treatment effect. Although the ultra-gravity method has a good mass transfer effect and can remove dust and soluble components in water, it usually requires a special absorbent to absorb components that are difficult to dissolve in water. The contaminated absorbent produced in the end is very difficult to handle. Summary of the invention

[0003] The purpose of the present invention is to provide a high-efficiency, low-energy consumption waste gas treatment method in view of the shortcomings of the above-mentioned prior art when using water absorption method and super gravity method to treat waste gas, so as to solve the problems of insufficient mass transfer in the prior art when using water absorption alone and the difficulty of treating contaminated absorbent by super gravity method.

[0004] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0005] The present invention provides a high-efficiency, low-energy consumption exhaust gas treatment method, which includes exhaust gas collection, pretreatment, exhaust gas oxidation, and exhaust gas washing links, wherein the exhaust gas collection unit has an outlet connected to an exhaust gas inlet of a pretreatment device, the pretreatment unit is respectively connected to an exhaust gas collection unit and an exhaust gas oxidation unit, and the exhaust gas oxidation unit has an outlet connected to the exhaust gas washing unit.

[0006] Furthermore, the exhaust gas collection process should minimize the collected air volume while meeting environmental protection standards.

[0007] Furthermore, the dirt removal equipment in the pretreatment step may be a bag dust collector or an electrostatic dust collector, and the dehumidification equipment may be a metal mesh dehumidifier or a membrane dehumidifier.

[0008] Furthermore, the waste gas oxidation step uses the MW-LEP microwave ultraviolet waste gas oxidation equipment of Shaanxi Qinglang Wancheng Environmental Protection Technology Co., Ltd.

[0009] Furthermore, the waste gas oxidation step may also use plasma waste gas oxidation equipment.

[0010] Furthermore, the waste gas washing step may use the ultra-gravity dust removal and washing equipment of the School of Engineering of Anhui University of Science and Technology.

[0011] Furthermore, the microwave ultraviolet waste gas oxidation equipment comprises a microwave source and an electrodeless ultraviolet lamp tube, the microwave source is arranged on the top of the microwave electrodeless ultraviolet waste gas oxidation equipment, and the electrodeless ultraviolet lamp tube is fixed in the microwave electrodeless ultraviolet oxidation treatment chamber through a lamp tube bracket.

[0012] Beneficial effects of the present invention: The present invention provides a high-efficiency, low-energy consumption waste gas treatment method, characterized in that: the method includes waste gas collection, pretreatment, waste gas oxidation, and waste gas washing links, wherein the gas outlet of the waste gas collection unit is connected to the gas inlet of the pretreatment equipment, the pretreatment unit is respectively connected to the waste gas collection unit and the waste gas oxidation unit, and the gas outlet of the waste gas oxidation unit is connected to the waste gas washing unit. The method first collects and pretreats the waste gas, mainly removing particulate matter and liquid water therein; then oxidizes the waste gas, oxidizing the water-insoluble components therein into components that are easily soluble in water and easily soluble in water; finally, the waste gas is washed with a high-performance gas washing device to transfer the water-soluble components and solid particulate matter into water. The process can effectively remove pollutants in the waste gas, including organic components, non-polar components and particulate matter, and can be widely used in the field of waste gas treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings in the specification without paying creative work.

[0014] Figure 1 A schematic diagram of a high-efficiency, low-energy consumption waste gas treatment method according to an embodiment of the present invention DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiment of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, rather than all the embodiments. The components of the embodiment of the present invention described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but only represents the selected embodiment of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0016] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the products of the invention in this specification are usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limitations on the present invention. In addition, the terms "first", "second", "third" and the like are only used to distinguish descriptions, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0017] Figure 1 A schematic diagram of a high-efficiency, low-energy consumption waste gas treatment method provided by an embodiment of the present invention; Figure 1 The present application is described in detail with reference to the embodiments.

[0018] The present invention provides a high-efficiency, low-energy consumption exhaust gas treatment method, characterized in that: the method includes exhaust gas collection, pretreatment, exhaust gas oxidation, and exhaust gas washing links, wherein the exhaust gas collection unit's air outlet is connected to the pretreatment equipment's air inlet, the pretreatment unit is respectively connected to the exhaust gas collection unit and the exhaust gas oxidation unit, and the exhaust gas oxidation unit's air outlet is connected to the exhaust gas washing unit.

[0019] It should be noted that in the embodiments described in this application, the waste gas oxidation treatment unit uses the MW-LEP microwave ultraviolet waste gas oxidation equipment of Shaanxi Qinglang Wancheng Environmental Protection Technology Co., Ltd. The waste gas washing link can use the ultra-gravity dust removal and washing equipment of the School of Engineering of Anhui University of Science and Technology.

[0020] Example 1

[0021] A new material technology company, the waste gas components are: benzene, toluene, xylene, the VOCs concentration before treatment is 190mg / m3-310mg / m3, after MW-LEP oxidation, the waste gas components before washing are formaldehyde, formic acid, acetaldehyde, acetic acid, propionaldehyde, propionic acid and solid hydrocarbons, after sufficient water washing treatment, the VOCs concentration in the waste gas is 2.5mg / m3. Analysis of the reasons: the solubility of benzene in water is 0.15g / 100mL, the solubility of toluene in water is 0.053g / 100mL, and the solubility of xylene in water is 0.3mg / L, all of which are substances that are not easily soluble in water. The solubility of formic acid generated after oxidation in water is 70g / 100mL, the solubility of acetic acid in water is 8.2g / 100mL, the solubility of acetic acid in water is 56g / 100mL, and the solubility of acetic acid in water is 12g / 100mL, which is 200-300 times higher than before oxidation. After sufficient water washing and mass transfer, most of the pollutants are transferred to the water, and the waste gas is effectively treated.

[0022] Example 2

[0023] The baking soda production line of the Chemical Group Company has waste gas components including ammonia, hydrogen sulfide, and VOCs. Before treatment, the ammonia concentration is 890-1130 mg / m3, the hydrogen sulfide concentration is 33 mg / m3, and the VOCs concentration is 132 mg / m3-156 mg / m3. After MW-LEP oxidation, the waste gas components before washing are nitrogen, water, sulfur, acetaldehyde, acetic acid, propionaldehyde, etc. After sufficient water washing treatment, the ammonia concentration in the waste gas is 0.04 mg / m3, the hydrogen sulfide concentration is 0.01 mg / m3, and the VOCs concentration is 0.5 mg / m3. Analysis of the reasons: Ammonia is oxidized into nitrogen and water in the MW-LEP equipment. The remaining ammonia has a solubility of 32.5g / 100mL in water. Hydrogen sulfide is oxidized into elemental sulfur, sulfur dioxide and sulfuric acid in the MW-LEP equipment, which are all absorbed by the scrubbing equipment. There is very little residual hydrogen sulfide. VOCs are oxidized into acetaldehyde, acetic acid, propionaldehyde, etc., which have high solubility and are easily absorbed and carried away by the water in the water washing equipment.

[0024] Example 3

[0025] The exhaust gas from the heating furnace in the rolling workshop of a steel plant has the following components: sulfur dioxide, nitrogen monoxide, and carbon monoxide. Before treatment, the concentration of sulfur dioxide was 200-400mg / m3, the concentration of nitrogen monoxide was 40-60mg / m3, and the concentration of carbon monoxide was 4000mg / m3-7000mg / m3. After MW-LEP oxidation, the exhaust gas components before washing were sulfur dioxide, sulfur trioxide, nitrogen dioxide, nitrogen monoxide, carbon dioxide and carbon monoxide. After sufficient water washing treatment, the sulfur dioxide concentration in the exhaust gas was 24mg / m3, the concentration of nitrogen monoxide was 1mg / m3, and the concentration of carbon monoxide was 200-300mg / m3. Analysis of the reasons: Sulfur dioxide is oxidized into sulfur trioxide in the MW-LEP equipment, leaving a part of sulfur dioxide. Nitrogen monoxide is insoluble in water, with a solubility of 4.7g / 100mL in water. Nitrogen dioxide oxidized in the MW-LEP equipment can react violently with water and is 100% soluble in water. CO is oxidized into carbon dioxide and is no longer a pollutant. Part of it is absorbed by water, and part of it is discharged into the air.

[0026] The present invention provides a high-efficiency, low-energy consumption waste gas treatment method, characterized in that: the method includes waste gas collection, pretreatment, waste gas oxidation, and waste gas washing links, wherein the gas outlet of the waste gas collection unit is connected to the gas inlet of the pretreatment equipment, the pretreatment unit is respectively connected to the waste gas collection unit and the waste gas oxidation unit, and the gas outlet of the waste gas oxidation unit is connected to the waste gas washing unit. This patent combines the advantages of microwave electrodeless ultraviolet technology and ultra-gravity dust removal technology, uses water as a washing medium, and washes and absorbs the waste gas oxidized by the microwave electrodeless ultraviolet equipment, so that various waste gases can be effectively treated at a lower cost and operating cost, and the pollutants therein can be transferred to sewage. This process can use the reclaimed water from sewage treatment as a detergent, which can greatly reduce the investment cost and operating cost of the waste gas treatment system. At the same time, since the waste gas contains fewer pollutants, it will not bring a large burden to the sewage treatment system, so it is a very good waste gas treatment method. This method can treat almost all current waste gas components, including mixed waste gas of one or more components of VOCs, NH3, H2S, CO, HCN, O3, chlorofluorocarbons, sulfur oxides and nitrogen oxides, and has wide application in the field of waste gas treatment.

[0027] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-efficiency, low-energy consumption waste gas treatment method, characterized in that: The method includes waste gas collection, pretreatment, waste gas oxidation, and waste gas washing steps, wherein the gas outlet of the waste gas collection unit is connected to the gas inlet of the pretreatment equipment, the pretreatment unit is respectively connected to the waste gas collection unit and the waste gas oxidation unit, and the gas outlet of the waste gas oxidation unit is connected to the waste gas washing unit.

2. A high-efficiency, low-energy consumption waste gas treatment method according to claim 1, characterized in that: The waste gas collection process should minimize the air volume while meeting environmental protection standards.

3. The high-efficiency, low-energy consumption waste gas treatment method according to claim 1 is characterized in that: The dirt removal equipment in the pretreatment step can be a bag dust collector or an electrostatic dust collector, and the dehumidification equipment can be a metal mesh dehumidifier or a membrane dehumidifier.

4. The high-efficiency, low-energy consumption waste gas treatment method according to claim 1 is characterized in that: The waste gas oxidation process uses the MW-LEP microwave ultraviolet waste gas oxidation equipment of Shaanxi Qinglang Wancheng Environmental Protection Technology Co., Ltd.

5. The high-efficiency, low-energy consumption waste gas treatment method according to claim 1 is characterized in that: The waste gas oxidation step uses plasma waste gas oxidation equipment.

6. The high-efficiency, low-energy consumption waste gas treatment method according to claim 1 is characterized in that: The waste gas washing process can use the ultra-gravity dust removal and washing equipment of the School of Engineering of Anhui University of Science and Technology.

7. A high-efficiency, low-energy consumption waste gas treatment method according to claim 4, characterized in that: The microwave ultraviolet waste gas oxidation equipment comprises a microwave source and an electrodeless ultraviolet lamp tube. The microwave source is arranged on the top of the microwave electrodeless ultraviolet waste gas oxidation equipment. The electrodeless ultraviolet lamp tube is fixed in the microwave electrodeless ultraviolet oxidation treatment chamber through a lamp tube bracket.

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