Deodorization system and process for waste gas treatment

Abstract

The invention discloses a deodorization system and technology for waste gas treatment and relates to the technical field of waste gas purification, the deodorization system comprises a waste gas conveying unit and a plasma purification unit, and the plasma purification unit comprises a shell, an air inlet pretreatment assembly, a reaction assembly, a pressure transformation assembly and a plasma conveying assembly; the reaction assembly comprises a dielectric layer, a catalyst layer, a high-voltage electrode and a grounding electrode; the deodorization system adopts a high-density dielectric barrier discharge ion technology, is driven by a high-frequency pulse power supply, and a dielectric layer of a reaction assembly is coated with a special catalyst layer, so that the density of generated plasma is far higher than that of a traditional technology, the removal rate of malodorous substances is greatly improved, and sewage and a large amount of hazardous waste are avoided; the deodorization process comprises the following steps: conveying plasmas generated by the deodorization system to be mixed with the waste gas, decomposing malodorous molecules, and purifying the waste gas.

Description

Technical Field

[0001] This application relates to the field of waste gas purification technology, and in particular to a deodorization system and process for waste gas treatment. Background Technology

[0002] Malodorous substances are gaseous pollutants that irritate the human olfactory organs, causing unpleasant or harmful sensations and damaging the environment. The sources of malodorous substances include domestic and industrial sources. Typical malodorous gases include hydrogen sulfide, mercaptans, diamines, and ammonia.

[0003] Odor gas purification technologies can be categorized into biological methods, adsorption methods, absorption methods, combustion methods, and low-temperature plasma methods based on their removal mechanisms. Each of these methods—biological, adsorption, absorption, and combustion—has its own limitations, including limited treatment efficiency, high operating costs, susceptibility to secondary pollution, and complex operation and maintenance.

[0004] In recent years, low-temperature plasma technology has been widely used as an emerging waste gas treatment technology. Its basic principle is to use a high-voltage electric field to ionize the gas, generating high-energy electrons, free radicals and other active particles. These active particles interact with pollutants in the waste gas, causing the pollutant molecules to decompose in a very short time.

[0005] Traditional plasma technology produces low-density active particles, which affects the equipment's purification efficiency for waste gas. Higher-density active particles can collide and react with pollutant molecules more frequently and effectively, thereby achieving a higher removal rate in a shorter time. Summary of the Invention

[0006] This application provides a deodorization system and process for waste gas treatment, which can generate high-density plasma to remove malodorous substances from waste gas.

[0007] In a first aspect, this application provides a deodorization system for treating waste gas, including a waste gas conveying unit, an plasma purification unit, and a reaction assembly. The waste gas conveying unit is used to convey waste gas into a main pipeline. The plasma purification unit includes a housing and an inlet pretreatment assembly, a reaction assembly, a transformer assembly, and a plasma conveying assembly disposed within the housing. The inlet pretreatment assembly is disposed within the housing and is used to convey gas to the reaction assembly. The transformer assembly is connected to the reaction assembly and is used to provide a high voltage to the reaction assembly, which is used to generate plasma. The plasma conveying assembly is connected to the reaction assembly and is used to convey plasma into the main pipeline. The reaction assembly includes a dielectric layer, a catalyst layer, a high-voltage electrode, and a ground electrode. The two dielectric layers are arranged opposite each other to form an ionization channel. One end of the ionization channel is connected to the inlet pretreatment assembly, and the other end is connected to the plasma conveying assembly. The catalyst layer is disposed inside the dielectric layer, and the high-voltage electrode and the ground electrode are respectively disposed on the outer side of the dielectric layer. The transformer assembly is electrically connected to the high-voltage electrode.

[0008] Preferably, the housing is provided with air inlet louvers, which are correspondingly arranged with the transformer assembly inside the housing.

[0009] Preferably, the housing is provided with an inspection door, an electrical control door, and an electric field inspection door.

[0010] Preferably, the intake pretreatment assembly includes a dryer and a filter connected in sequence, with the filter connected to the reaction assembly.

[0011] Preferably, the dielectric layer is configured as a transparent glass layer.

[0012] Preferably, a catalyst layer is formed by coating the inner side of the medium layer with a transition metal oxide composite catalyst.

[0013] Preferably, it also includes an exhaust gas purification unit, which is connected to the outlet end of the main pipeline and is used to treat the exhaust gas after reacting with the plasma.

[0014] Preferably, the exhaust gas purification unit includes an acid washing tower and an alkaline washing tower connected to each other, with the acid washing tower connected to the outlet end of the main pipeline.

[0015] Secondly, this application provides a deodorization process for waste gas treatment, using a deodorization system, the deodorization process including: Step S100: The generated waste gas is transported to the main pipeline through the waste gas conveying unit; Step S200: The reaction components of the plasma purification unit generate a high-voltage electric field, which generates plasma. The plasma is transported to the main pipeline through the plasma transport components and mixes with the exhaust gas in the main pipeline to decompose odor molecules and purify the exhaust gas. In step S300, the waste gas treated in step S200 passes through an acid washing tower and an alkaline washing tower in sequence to remove residual pollutants. Step S400: The purified gas is discharged through the exhaust stack in compliance with standards.

[0016] Preferably, both the acid washing tower and the alkali washing tower are configured as spray towers, with the acid washing tower spray solution being a dilute sulfuric acid solution and the alkali washing tower spray solution being a sodium hydroxide aqueous solution.

[0017] The deodorization system and process of this application have at least the following beneficial effects: The deodorization system of this application adopts high-density dielectric barrier discharge ion technology, driven by a high-frequency pulse power supply. The dielectric layer of the reaction component is coated with a special catalyst layer, and the generated plasma density is much higher than that of traditional technology, which greatly improves the removal rate of malodorous substances and produces no wastewater or large amounts of hazardous waste. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the deodorization system of this application. Arrow ① indicates the air flow direction, arrow ② indicates the plasma flow direction, arrow ③ indicates the exhaust gas flow direction, and arrow ④ indicates the flow direction of the products after the exhaust gas reacts with the plasma. Figure 2 This is a cross-sectional schematic diagram of the reaction component of this application; Figure 3 This is a flowchart of the deodorization process in this application; The annotations in the attached figures are explained as follows: 100. Exhaust gas conveying unit; 110. Main pipeline; 200. Plasma purification unit; 210. Housing; 211. Air inlet louvers; 212. Inspection door; 213. Electrically controlled door; 214. Electric field inspection door; 220. Air intake pretreatment assembly; 221. Dryer; 222. Filter; 230. Reaction assembly; 231. Medium layer; 232. Catalyst layer; 233. High-voltage electrode; 234. Grounding electrode; 230a. Ionization channel; 240. Transformer assembly; 250. Plasma transport assembly; 260. Electrical control unit; 300. Exhaust gas purification unit; 310. Acid washing tower; 320. Alkali washing tower. Detailed Implementation

[0019] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0020] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0021] Example 1: This embodiment discloses a deodorization system and process for waste gas treatment. First, the deodorization system of this embodiment will be introduced.

[0022] like Figure 1 As shown, the deodorization system includes an exhaust gas conveying unit 100, an plasma purification unit 200, and an exhaust gas purification unit 300. In some preferred embodiments, the deodorization system also includes an intelligent control unit.

[0023] like Figure 1 As shown, the exhaust gas conveying unit 100 includes a conveying fan and a main pipeline 110, and the conveying fan continuously conveys the exhaust gas into the main pipeline 110.

[0024] like Figure 1 As shown, the plasma purification unit 200 includes a housing 210, an air intake pretreatment assembly 220, a reaction assembly 230, a transformer assembly 240, and a plasma delivery assembly 250, as detailed below: like Figure 1 As shown, the housing 210 is made of 304 stainless steel and is rectangular in shape. The housing 210 has an air inlet and a plasma outlet on its two sides, respectively.

[0025] like Figure 1As shown, the intake pretreatment assembly 220 includes a dryer 221 and a filter 222, both disposed within the housing 210. The dryer 221 is connected to the air inlet on the housing 210, the outlet of the dryer 221 is connected to the inlet of the filter 222, and the outlet of the filter 222 is connected to the reaction assembly 230. In this embodiment, the intake pretreatment assembly 220 dries and filters the intake air, removing dust and increasing the plasma density. In other embodiments, the intake pretreatment assembly 220 uses a fan disposed within the air inlet to drive external air into the dryer 221.

[0026] like Figure 2 As shown, the reaction assembly 230 is disposed within the housing 210 and is used to ionize and generate high-density plasma. The reaction assembly 230 includes a dielectric layer 231, a catalyst layer 232, a high-voltage electrode 233, and a ground electrode 234. The number of dielectric layers 231 is at least two, and two are a pair. In this embodiment, multiple pairs of dielectric layers 231 can be provided. Two dielectric layers 231 are arranged at intervals to form an ionization channel 230a (the interval distance is designed according to actual needs). The number of catalyst layers 232 corresponds one-to-one with the number of dielectric layers 231. The catalyst layers 232 are disposed inside the dielectric layers 231, that is, the catalyst layers 232 are located within the ionization channel 230a. The high-voltage electrode 233 can be connected to a dielectric layer 231 in a one-to-one or one-to-many manner, specifically on the side of the dielectric layer 231 away from the ionization channel 230a. Similarly, the ground electrode 234 can be connected to another dielectric layer 231 in a one-to-one or one-to-many manner, specifically on the side of the dielectric layer 231 away from the ionization channel 230a.

[0027] In this embodiment, the high-voltage electrode 233 or the ground electrode 234 is preferably made of stainless steel, copper or aluminum.

[0028] In this embodiment, preferably, the medium layer 231 is configured as a fully transparent glass layer, and a transition metal oxide composite catalyst is coated on the inner side of the medium layer 231 to form the catalyst layer 232.

[0029] In some preferred embodiments, the reaction assembly 230 comprises multiple pairs of plate-shaped, fully transparent, specially designed glass electrodes coated with a special catalyst, arranged in an array. Under the action of a high-frequency, high-voltage electric field, it generates a high-density plasma with three-dimensional ultraviolet light and an active particle concentration greater than 10. 14 / cm3, with a discharge efficiency greater than 90%, and its odor treatment efficiency is several times that of traditional low-temperature plasma technology.

[0030] like Figure 1As shown, the transformer assembly 240 is disposed within the housing 210 and is electrically connected to the high-voltage electrode 233. It is used to convert low voltage into high voltage, applying an electric field to the reaction assembly 230, causing air to be ionized and plasma to be generated. The transformer assembly 240 is based on an existing transformer.

[0031] like Figure 1 As shown, a plasma delivery assembly 250 is disposed within the housing 210. The plasma delivery assembly 250 is used to deliver plasma to the main pipeline 110. The plasma delivery assembly 250 includes a delivery pipeline, one end of which is connected to the outlet end of the reaction assembly 230, i.e., the outlet end of the ionization channel 230a. The other end of the delivery pipeline is connected to a plasma outlet disposed on the housing 210, and the plasma outlet is connected to the main pipeline 110. Preferably, in this embodiment, the plasma delivery assembly 250 further includes a variable frequency fan connected to the delivery pipeline, which drives the plasma along the delivery pipeline to be delivered to the main pipeline 110.

[0032] like Figure 1 As shown, in this preferred embodiment, the plasma purification unit 200 further includes an electrical control unit 260 disposed within the housing 210, and the electrical control unit 260 is electrically connected to the transformer assembly 240.

[0033] like Figure 1 As shown in this embodiment, preferably, the housing 210 is also provided with an air inlet louver 211, which is correspondingly provided with the transformer assembly 240, so that air can enter from the air inlet louver 211 to dissipate heat from the transformer assembly 240.

[0034] like Figure 1 As shown in the preferred embodiment, the housing 210 is also provided with a maintenance door 212, an electrical control door 213 and an electric field maintenance door 214. The maintenance door 212 is located on the side close to the plasma delivery assembly 250, the electrical control door 213 is located on the side close to the electrical control unit 260, and the electric field maintenance door 214 is located on the side close to the reaction assembly 230.

[0035] In this embodiment, the preferred airflow velocity inside the plasma purification unit 200 is 20-50 m / s, and the residence time of the airflow is 10-100 ms.

[0036] In this embodiment, the plasma purification unit 200 preferably has a self-cleaning function, which can regenerate the deactivated catalyst by introducing clean air and turning it on for half an hour.

[0037] In this preferred embodiment, the plasma purification unit 200 can handle a maximum air volume of 50,000 m³ / h. 3 / h, multiple ionization purification units of 200 can be used in parallel when dealing with extremely large volumes of exhaust gas, and there is a large range of adjustment.

[0038] like Figure 1 As shown, the exhaust gas purification unit 300 is connected to the outlet end of the main pipeline 110 and is used to treat the products after the waste gas and plasma are mixed and reacted. The exhaust gas purification unit 300 includes an acid washing tower 310 and an alkaline washing tower 320. The inlet of the acid washing tower 310 is connected to the outlet end of the main pipeline 110, and the outlet of the acid washing tower 310 is connected to the inlet of the alkaline washing tower 320.

[0039] The intelligent control unit is used to collect and monitor parameters during equipment operation to realize intelligent operation of the system. In this embodiment, the intelligent control unit includes an online monitoring device and an automatic control module. The online monitoring device is electrically connected to the automatic control module. The online monitoring device includes various sensors, such as a first pressure sensor located at the air inlet of the housing 210 and a second pressure sensor located at the plasma outlet. The pressure difference can be obtained from the two pressure sensors. For example, a solenoid valve or other automatically controllable valve is installed in the delivery pipeline.

[0040] This embodiment also discloses a deodorization process for waste gas treatment, which uses the above-mentioned deodorization system.

[0041] like Figure 3 As shown, the deodorization process includes: Step S100: The generated waste gas is transported to the main pipeline 110 through the waste gas conveying unit 100; In step S200, the reaction component 230 of the plasma purification unit 200 generates a high-voltage electric field, and plasma is generated under the action of the high-voltage electric field. The plasma is transported to the main pipe 110 through the plasma transport component 250. The plasma and the waste gas mix and interact in the main pipe 110, decomposing odor molecules and purifying the waste gas. In step S300, the waste gas treated in step S200 passes through acid washing tower 310 and alkaline washing tower 320 in sequence to remove residual pollutants. Step S400: The purified gas is discharged through the exhaust stack in compliance with standards.

[0042] In this embodiment, preferably, both the acid washing tower 310 and the alkali washing tower 320 are spray towers, the spray liquid of the acid washing tower 310 is a dilute sulfuric acid solution, and the spray liquid of the alkali washing tower 320 is an aqueous sodium hydroxide solution.

[0043] In this embodiment, preferably, the interval between the high-density plasma entering the main pipe 110 is less than 500ms, to ensure that the waste gas and the high-density plasma are fully mixed and reacted in the main pipe 110.

[0044] In this embodiment, the exhaust gas includes sulfur- and nitrogen-containing gases, such as those generated during the evaporation of magnesium ammonium sulfate and other chemical processes.

[0045] The deodorization system and deodorization process of this embodiment have the following advantages: (1) Improved treatment efficiency and no secondary pollution: High-density dielectric barrier discharge ion technology is adopted, driven by high-frequency pulse power supply. The electrodes are made of fully transparent special glass material and coated with special catalyst. The generated plasma density is high, the removal rate of malodorous substances is greatly improved, and there is no sewage or large amount of hazardous waste.

[0046] (2) The ion implantation process is adopted, the waste gas does not need to be pretreated, and the electrode does not come into direct contact with the waste gas, thus avoiding the problem of electrode corrosion and extending the service life of the equipment. (3) Simple process flow and integrated system: The waste gas conveying unit 100, plasma purification unit 200 and tail gas purification unit 300 are integrated. The equipment volume is less than 10% of that of traditional equipment. Through intelligent control unit, automated operation and remote monitoring are realized. Example 2: This second embodiment discloses a deodorization process for waste gas treatment, used to treat sulfur- and nitrogen-containing waste gas generated during the evaporation and concentration of magnesium ammonium sulfate wastewater (waste gas parameters: air volume 5000 m³ / h). 3 / h, temperature 50℃, relative humidity 85%, odor concentration 4500 dimensionless), using the deodorization system of Example 1, such as Figure 3 As shown, it includes the following steps: In step S100, sulfur- and nitrogen-containing waste gas is transported through the main waste gas pipeline 110; In step S200, the plasma purification unit 200 generates high-density plasma under the action of a high-voltage electric field. The high-density plasma is transported by a fan to the main pipeline 110 through the conveying pipeline, where it interacts with the sulfur- and nitrogen-containing waste gas transported in step S100, decomposing malodorous substances such as H2S and NH3 into low-odor or odorless substances such as SO3 and N2. In step S300, the gas processed in step S200 passes sequentially through acid washing tower 310 and alkaline washing tower 320, SO3 is converted into Na2SO4, and O3 generated by the plasma purification unit 200 is converted into O2, thus removing residual pollutants. Step S400: Finally, the purified gas is discharged through the exhaust stack in compliance with standards.

[0047] The deodorization process in this embodiment can reduce the odor concentration of the exhaust gas to 750 dimensionless, demonstrating a significant deodorization effect. This deodorization process can stably treat the initial odor concentration of over 4000 (dimensionless) to below 800 (dimensionless), meeting the "Odor Pollutant Emission Standard" (GB14554-93). It has high deodorization efficiency, and energy consumption and operating costs are reduced by more than 50% compared to traditional technologies.

[0048] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A deodorization system for treating waste gas, characterized in that, include: The exhaust gas conveying unit (100) is used to convey exhaust gas into the main pipeline (110); The plasma purification unit (200) includes a housing (210) and an intake pretreatment assembly (220), a reaction assembly (230), a transformer assembly (240), and a plasma delivery assembly (250) disposed within the housing (210). The intake pretreatment assembly (220) is disposed within the housing (210) and is used to deliver gas to the reaction assembly (230). The transformer assembly (240) is connected to the reaction assembly (230) and is used to provide high voltage to the reaction assembly (230), which is used to generate plasma. The plasma delivery assembly (250) is connected to the reaction assembly (230) and is used to deliver plasma to the main pipeline (110). The reaction assembly (230) includes a dielectric layer (231), a catalyst layer (232), a high-voltage electrode (233), and a ground electrode (234). The two dielectric layers (231) are arranged opposite each other to form an ionization channel (230a). One end of the ionization channel (230a) is connected to the inlet pretreatment assembly (220), and the other end is connected to the plasma transport assembly (250). The catalyst layer (232) is disposed inside the dielectric layer (231), and the high-voltage electrode (233) and the ground electrode (234) are respectively disposed on the outside of the dielectric layer (231). The transformer assembly (240) is electrically connected to the high-voltage electrode (233).

2. The deodorization system according to claim 1, characterized in that, An air inlet louver (211) is provided on the housing (210), and the air inlet louver (211) is correspondingly provided with the transformer assembly (240) inside the housing (210).

3. The deodorization system according to claim 2, characterized in that, The housing (210) is provided with an inspection door (212), an electrical control door (213), and an electric field inspection door (214).

4. The deodorization system according to claim 1, characterized in that, The intake pretreatment assembly (220) includes a dryer (221) and a filter (222) connected in sequence, with the filter (222) connected to the reaction assembly (230).

5. The deodorization system according to any one of claims 1 to 4, characterized in that, The dielectric layer (231) is configured as a transparent glass layer.

6. The deodorization system according to claim 5, characterized in that, The catalyst layer (232) is formed by coating the inner side of the medium layer (231) with a transition metal oxide composite catalyst.

7. The deodorization system according to claim 1, characterized in that, It also includes an exhaust gas purification unit (300), which is connected to the outlet end of the main pipe (110) and is used to treat the exhaust gas after it reacts with the plasma.

8. The deodorization system according to claim 7, characterized in that, The exhaust gas purification unit (300) includes an acid washing tower (310) and an alkaline washing tower (320) connected to each other. The acid washing tower (310) is connected to the outlet end of the main pipeline (110).

9. A deodorization process for treating waste gas, characterized in that, Using the deodorization system according to any one of claims 1 to 8, the deodorization process includes: Step S100: The generated waste gas is transported to the main pipeline (110) through the waste gas conveying unit (100). In step S200, the reaction component (230) of the plasma purification unit (200) generates a high-voltage electric field. Under the action of the high-voltage electric field, plasma is generated. The plasma is transported to the main pipe (110) through the plasma transport component (250) and mixes with the waste gas in the main pipe (110) to decompose odor molecules and purify the waste gas. In step S300, the waste gas treated in step S200 passes through an acid washing tower (310) and an alkaline washing tower (320) in sequence to remove residual pollutants; Step S400: The purified gas is discharged through the exhaust stack in compliance with standards.

10. The deodorization process according to claim 9, characterized in that, Both the acid washing tower (310) and the alkali washing tower (320) are configured as spray towers. The spray liquid of the acid washing tower (310) is a dilute sulfuric acid solution, and the spray liquid of the alkali washing tower (320) is an aqueous sodium hydroxide solution.

Images