CN102861504B - Device for treating organic waste gas by applying photochemical technology - Google Patents

Abstract

A device for treating organic waste gas by applying a photochemical technology comprises a high-strength security filter screen, a plasma reactor, a liquid mist humidifier, a catalytic reaction screen, an adsorption reaction screen, an ultraviolet lamp unit and an electric controller; the catalytic reaction screen and the adsorption reaction screen are subjected to the irradiation of the ultraviolet lamp unit; the organic waste gas is purified after being filtered by the high-strength filter screen, decomposed by the plasma reactor, humidified and cooled by the liquid mist humidifier, catalyzed by the catalytic reaction screen and adsorbed by the adsorption reaction screen; and the electric controller is connected to the plasma reactor and the ultraviolet lamp unit and used for controlling the starting and stopping of the plasma reactor and the ultraviolet lamp unit. The device for treating the organic waste gas by applying the photochemical technology can be used for efficiently treating industrial organic waste gas, does not produce secondary pollution residues and is lower in resource consumption and operation cost.

Description

A device for treating organic waste gas with photochemical technology

technical field

The invention relates to a device for treating organic waste gas using photochemical technology, which is used for purifying the organic waste gas produced in the industrial production process, and belongs to the technical field of protection of the atmosphere and the living environment of urban and rural residents.

Background technique

Air pollution is one of the most prominent environmental problems in my country at present. Among them, industrial waste gas is an important source of air pollutants. The most difficult to deal with in industrial waste gas is organic waste gas, which mainly includes various hydrocarbons, alcohols, aldehydes, acids, ketones and amines. They mainly come from the waste gas discharged during the production process of the petroleum and chemical industries. They are characterized by large quantities, large fluctuations in organic matter content, flammability, certain toxicity, and some have stench, and the emission of chlorofluorocarbons can also cause ozone layer damage. destroy. Petroleum and chemical factories and storage facilities of petrochemical products, printing and other industries related to petroleum and chemical products, occasions and combustion equipment using petroleum and petrochemical products, and various vehicles fueled by petroleum products are all sources of organic waste gas .

After organic waste gas enters the human body through the respiratory tract and skin, it can cause temporary and permanent damage to human respiratory, blood, liver and other systems and organs, especially polycyclic aromatic hydrocarbons can directly cause cancer in the human body. In addition to causing direct air pollution, these organic waste gases will also generate secondary pollutants through a series of complex reactions under the action of sunlight, becoming one of the main sources of PM2.5. Therefore, the treatment and purification of organic waste gas is imperative.

For a long time, many scholars at home and abroad have been committed to the research of VOCs pollution control technology. Traditional technologies include adsorption, condensation, membrane separation, etc., and new technologies include low-temperature plasma, photocatalytic oxidation, and biological treatment.

Adsorption method is currently the most widely used and most mature method. Generally, activated carbon is the first choice as the adsorbent, which has the advantages of strong adsorption capacity and sufficient raw materials. At present, a two-stage circulating fluidized bed is used to adsorb VOCs waste gas, which is stable and effective. Modifications such as oxidation, reduction, and loading of compounds on activated carbon can further improve its adsorption capacity. But at present, a set of mature, reliable, economical and applicable activated carbon regeneration technology has not been formed in China. Most activated carbon is disposed of as solid waste after use, causing secondary pollution, which restricts the application of activated carbon adsorption technology in recent years.

The principle of the condensation method is to use the different vapor pressures of gaseous pollutants, and adjust the temperature and pressure to make the target pollutants supersaturated and condense to achieve purification and recovery. This technology has a good treatment effect on some organic matter and is conducive to the recovery of useful raw materials. However, this method consumes a lot of energy, and the cost of low-concentration organic waste gas treatment is high, and the recovery rate is low, so it has not been widely used.

The principle of membrane separation technology is to use the different rates of VOCs exhaust gas components to pass through the selective membrane under pressure to separate the target pollutants. This method is suitable for the treatment of organic waste gas with small treatment volume and high concentration.

The principle of biological treatment of VOCs waste gas is to cultivate and domesticate specific microorganisms by controlling suitable environmental conditions, and use the pollutants in the waste gas as carbon sources and energy sources to maintain their life activities, and at the same time convert pollutants into inorganic substances. So as to achieve the purpose of purification. Biological treatment of waste gas has the advantages of good treatment effect, low operating cost, and no secondary pollution. However, the operation and management of this method is complicated, and it takes a long time for the system to recover the processing capacity after shutdown, and it occupies a large area, so it is difficult to apply to large-scale organic waste gas treatment projects.

The principle of low-temperature plasma technology is to use corona discharge, radio frequency discharge, etc. to obtain a large number of high-energy electrons and active particles such as O and OH at room temperature and pressure, and use these active particles to convert VOCs waste gas into CO ₂ , H ₂ O and other harmless or low-hazardous substances. Low-temperature plasma technology has the advantages of simple process, strong applicability, easy operation, and low energy consumption, and has become a cutting-edge technology for treating VOCs waste gas.

Photocatalytic oxidation technology has a good ability to treat wastewater and has been widely used, while the use of photocatalytic oxidation technology to treat VOCs waste gas is a new technology. A large number of studies have shown that photocatalytic oxidation technology can degrade organic matter in exhaust gas into inorganic matter at normal temperature and pressure, so it has great application value.

Contents of the invention

The object of the present invention is to provide a device for treating organic waste gas using photochemical technology, which can efficiently treat industrial organic waste gas without producing secondary pollution residues, consumes less resources, and has lower operating costs.

In order to achieve the above purpose, the present invention is a device for treating organic waste gas using photochemical technology, including high-strength security filter screen, plasma reactor, liquid mist humidifier, catalytic reaction network, adsorption reaction network, ultraviolet lamp group and electrical controller , the catalytic reaction network and the adsorption reaction network are irradiated by the ultraviolet lamp group, the organic waste gas is filtered through the high-strength security filter in turn, the plasma reactor is decomposed, the liquid mist humidifier is humidified and cooled, the catalytic reaction network is catalyzed, and the adsorption reaction network After adsorption and purification, the electrical controller connects the plasma reactor and the ultraviolet lamp group to control the start and stop of the plasma reactor and the ultraviolet lamp group.

The present invention also includes an air inlet flange and an air outlet flange, and the high-strength security filter, plasma reactor, liquid mist humidifier, catalytic reaction net, adsorption reaction net and ultraviolet lamp group are all arranged in the main body of the equipment structure , the air inlet flange and the air outlet flange are respectively arranged at both ends of the main body of the equipment structure. The main body of the equipment structure preferably adopts the main body of the steel structure of the equipment.

The high-strength security filter screen can be made of composite material fibers with a thickness of 5-10 cm. It is mainly used to intercept inorganic substances and large particles of oil droplets in the flue gas to protect the normal operation of subsequent components.

The plasma reactor can adopt pulsed corona discharge or wire-tube corona discharge, and is arranged behind the high-strength security filter, perpendicular to the direction of the wind. When the flue gas passes through the plasma reactor, due to the action of strong corona discharge, a large number of active high-energy particles such as electrons and charged particles are formed. Through the collision between these high-energy particles and organic matter and a series of chemical reactions, the organic matter is finally decomposed into relatively Stable non-hazardous or low-hazardous substances.

The liquid mist humidifier is set on the top of the main body of the equipment structure behind the high-strength security filter, and the tap water or pure water is obtained by connecting the tap water pressure pipeline or pumped by a pump, and the water mist is formed through the atomizing nozzle, and the flue gas is sprayed. Cool down and humidify. When the humidified flue gas passes through the subsequent catalytic reaction net, the water molecules in the flue gas continuously replenish the hydroxyl radicals for the catalyst on the surface of the catalytic reaction net to form continuous catalytic activity.

The catalytic reaction net can be made of nickel, on which nano-scale titanium dioxide photocatalyst is immobilized.

The adsorption reaction net can be made of a composite material containing activated carbon.

The catalytic reaction net and the adsorption reaction net are preferably cylindrical, with their central axes coincident and parallel to the wind inlet direction. According to the different processing capacity, the cylindrical catalytic reaction network is provided with one or more layers, the cylindrical adsorption reaction network is provided with one layer, and the distance between adjacent cylindrical catalytic reaction networks and or the distance between adjacent cylindrical catalytic reaction networks and the cylinder The spacing between the adsorption reaction nets is 10-20cm. The ultraviolet lamp group is optimally arranged between adjacent cylindrical catalytic reaction nets or between adjacent cylindrical catalytic reaction nets and cylindrical adsorption reaction nets, and the axes of the ultraviolet lamp groups are parallel to the air inlet direction. When the organic waste gas flows through the cylindrical catalytic reaction network, it contacts with the photocatalyst on the surface of the catalytic reaction network. Under the irradiation of the ultraviolet light emitted by the ultraviolet lamp group, the photocatalyst forms electron-hole pairs and hydroxyl radicals on the surface to rapidly oxidize the organic matter in the flue gas. Decompose to form stable and harmless substances such as carbon dioxide and water. After catalysis and photolysis purification, the remaining organic pollutants in the flue gas are finally trapped by the porous activated carbon medium on the cylindrical adsorption reaction net, and the adsorbed activated carbon will be gradually decomposed under the ultraviolet light emitted by the ultraviolet lamp group, and finally Converted into stable inorganic substances such as water and carbon dioxide, the porous activated carbon medium is regenerated.

The present invention mainly utilizes multiple effects such as physical interception and adsorption, low-temperature plasma, photoionization, ozone oxidation, free radical oxidation, and hole oxidation. First, through the high-strength security filter, the inorganic particles or oil droplets with large particle sizes that may be entrained in the organic waste gas are intercepted to protect the normal operation of subsequent components; A large number of electrons and active charged particles are obtained under the environment, and the organic pollutants in the flue gas are converted into harmless or low-harmful substances through the interaction between the active charged particles; after that, the flue gas is sprayed and humidified by a liquid mist humidifier; Then enter the photochemical reaction area from the outside of the cylindrical catalytic reaction network. The organic waste gas passes through the cylindrical catalytic reaction network, the ultraviolet lamp group, and the cylindrical adsorption reaction network in sequence, and finally is discharged from the air outlet flange through the air outlet pipe. Among them, when the organic waste gas passes through the surface of the cylindrical catalytic reaction network, it contacts with the strong oxidizing free radicals on the surface of the photocatalyst on the catalytic reaction network, and the organic pollutants in the waste gas are decomposed by photoionization, ozone oxidation, free radical oxidation, and hole oxidation effects. Degradation and purification can effectively eliminate organic pollutants in the flue gas that may cause atmospheric PM2.5 pollution. The present invention applies low-temperature plasma purification technology and photocatalysis technology, so that various active free radicals and strong oxidants can be combined and used at the same time, and the interactive and synergistic effect between them has played a synergistic comprehensive catalytic effect, greatly accelerating the photolysis and oxidation reaction rate , The purification process of photolysis and oxidation is less than 0.1 second, which greatly improves the efficiency of purification of organic pollutants.

In summary, the present invention has the following technical effects:

1. The plasma reactor is used, and the low-temperature plasma technology is used to pretreat the organic waste gas. A large number of electrons and high-energy active particles are formed through corona polarization, which effectively decomposes the macromolecular organic matter in the waste gas, which is conducive to the subsequent series of degradation reactions. conduct.

2. The liquid mist humidification device is adopted, which not only humidifies and cools the organic waste gas, but also provides a continuous and effective source of free radicals for the subsequent photocatalytic reaction, ensuring the continuous and efficient progress of the catalytic reaction.

3. The catalytic reaction network is adopted. The catalytic reaction network accepts the irradiation of ultraviolet lamps, applies photochemical and catalytic catalytic technology, and uses photoionization, ozone oxidation, free radical oxidation and hole oxidation through the comprehensive action of ultraviolet rays and catalyst solid carriers. and other effects to quickly and thoroughly purify the organic waste gas.

4. The adsorption reaction network is adopted, and the adsorption reaction network is irradiated by the ultraviolet lamp group, and the organic pollutants adsorbed by the activated carbon on the surface of the adsorption reaction network are thoroughly decomposed by using the ultraviolet light photolysis effect, so as to realize the regeneration of the activated carbon and make the adsorption reaction network last Work efficiently.

5. It adopts a cylindrical multilayer structure, cleverly integrates the functions of catalysis-photolysis-adsorption, and uses the effects of liquid mist and ultraviolet rays to realize the sustainability of catalytic activity of the catalyst and the recycling of activated carbon.

Description of drawings

Fig. 1 is the structural representation of the embodiment of the present invention;

Fig. 2 is the cross-sectional view of one layer of cylindrical catalytic reaction network, one layer of ultraviolet lamp group and one layer of cylindrical adsorption reaction network of Fig. 1;

Fig. 3 is the sectional view of two-layer cylindrical catalytic reaction network, two-layer ultraviolet lamp group, and one-layer cylindrical adsorption reaction network;

FIG. 4 is a flow diagram of the air flow in FIG. 1 .

Detailed ways

Embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in Figures 1 to 4, this embodiment is a device for treating organic waste gas using photochemical technology, including air inlet flange 1, equipment steel structure main body 2, air outlet flange 3, high-strength security filter 4, plasma Reactor 5, liquid mist humidifier 6, cylindrical catalytic reaction network 7, ultraviolet lamp group 8, cylindrical adsorption reaction network 9 and electrical controller 10; Both ends of the steel structure main body 2, high-strength security filter 4, plasma reactor 5, liquid mist humidifier 6, cylindrical catalytic reaction net 7, ultraviolet lamp group 8 and cylindrical adsorption reaction net 9 are all arranged on the equipment steel In the structural body 2, the high-strength security filter 4 is made of stainless steel and composite material fibers, and is arranged behind the air inlet flange 1, with a thickness of 5-10 cm; the plasma reactor 5 adopts pulse corona discharge or wire-tube type corona discharge, arranged behind the high-strength security filter 4, perpendicular to the air inlet direction 11; the liquid mist humidifier 6 is arranged on the top of the steel structure main body 2 of the equipment behind the high-strength security filter, connected to the tap water pressure pipe or Tap water or pure water is obtained by pumping; the cylindrical catalytic reaction network 7 and the cylindrical adsorption reaction network 9 have their central axes coincident and parallel to the wind inlet direction 11, and are fixed in the steel structure main body 2 of the equipment. As shown in Fig. 2 and Fig. 3, according to the difference of processing capacity, the present invention is provided with one or more layers of cylindrical catalytic reaction network 7 and one layer of cylindrical adsorption reaction network 9, and the central axis of each layer of catalytic/adsorption reaction network overlaps. The distance between adjacent cylindrical catalytic reaction nets, and the distance between adjacent cylindrical catalytic reaction nets and cylindrical adsorption reaction nets is 10-20cm; the cylindrical catalytic reaction net 7 is made of nickel, and nano-scale titanium dioxide photocatalyst is immobilized on it; The adsorption reaction net 9 is made of a composite material containing activated carbon; the ultraviolet lamp group 8 is arranged between adjacent cylindrical catalytic reaction nets 7, between adjacent cylindrical catalytic reaction nets 7 and cylindrical adsorption reaction nets 8, The axis of the ultraviolet lamp group 8 is parallel to the wind inlet direction 11; the plasma reactor 5 and the ultraviolet lamp group 8 are connected with the electrical controller 10 through wires.

When in use, the organic waste gas enters the steel structure main body 2 of the equipment through the air inlet flange 1. First, the high-strength security filter 4 intercepts the inorganic matter and large-particle oil droplets in the flue gas to protect the normal operation of subsequent components; The gas enters the plasma reactor 5, and under the action of the strong corona discharge in the plasma reactor 5, a large number of active high-energy particles such as electrons and charged particles are produced in the flue gas. Through the collision between these high-energy particles and organic matter and a series of chemical reaction, and finally decompose the organic matter into relatively stable harmless or low-harm substances; after passing through the plasma reactor 5, the organic waste gas is cooled and humidified by the liquid mist humidifier 6; the flue gas after cooling and humidification is catalyzed The outside of the reaction net 7 enters into the photochemical reaction area. The organic waste gas passes through the cylindrical catalytic reaction network 7, the ultraviolet lamp group 8, and the cylindrical adsorption reaction network 9 in sequence, and finally is discharged from the air outlet flange 3 through the air outlet pipe. Among them, when the organic waste gas flows through the cylindrical catalytic reaction net 7, it contacts with the catalyst on the surface 7 of the cylindrical catalytic net. The organic matter in the gas is quickly oxidized and decomposed to form stable and harmless substances such as carbon dioxide and water; at the same time, the ultraviolet rays emitted by the ultraviolet lamp group 8 have a catalytic decomposition effect on the organic pollutants in the flue gas. Under the irradiation of ultraviolet rays, some organic matter is photolyzed into small molecular substances; after catalysis and photolysis purification, the remaining organic pollutants in the flue gas are finally intercepted by the porous activated carbon medium on the cylindrical adsorption reaction network 9, and the adsorbed activated carbon is irradiated by the ultraviolet rays emitted by the ultraviolet lamp group 8 , the organic matter will be gradually decomposed, and finally converted into stable inorganic matter such as water and carbon dioxide, and the porous activated carbon medium will be regenerated. After the above series of photoionization, ozone oxidation, free radical oxidation, and hole oxidation effects, the organic pollutants in the organic waste gas are completely degraded and purified.

Claims (5)

1. A device for treating organic waste gas using photochemical technology, comprising a high-strength security filter (4), a plasma reactor (5), characterized in that it also includes a liquid mist humidifier (6), a catalytic reaction net (7 ), adsorption reaction network (9), ultraviolet lamp group (8) and electric controller (10), described catalytic reaction network (7) and adsorption reaction network (9) accept the irradiation of ultraviolet lamp group (8), organic waste gas Sequentially filtered through the high-strength security filter (4), decomposed by the plasma reactor (5), humidified and cooled by the liquid mist humidifier (6), catalyzed by the catalytic reaction network (7), purified after adsorption by the adsorption reaction network (9), The electrical controller (10) is connected to the plasma reactor (5) and the ultraviolet lamp group (8), and the catalytic reaction network (7) is made of nickel, on which a nano-scale titanium dioxide photocatalyst is solidly loaded, and the adsorption reaction The net (9) is made of a composite material containing activated carbon. The catalytic reaction net (7) and the adsorption reaction net (9) are cylindrical, and their central axes coincide and are parallel to the air inlet direction (11). The catalytic reaction network (7) is provided with one or more layers, and the cylindrical adsorption reaction network (9) is provided with one layer, and the distance between adjacent cylindrical catalytic reaction networks (7) and or the adjacent cylindrical catalytic reaction network (7) The distance from the cylindrical adsorption reaction net (9) is 10 to 20 cm, and the ultraviolet lamp group (8) is arranged between adjacent cylindrical catalytic reaction nets (7) or between adjacent cylindrical catalytic reaction nets (7) ) and the cylindrical adsorption reaction net (9), the axis of the ultraviolet lamp group (8) is parallel to the air inlet direction (11). 2. The device for treating organic waste gas according to claim 1, characterized in that: it includes an air inlet flange (1) and an air outlet flange (3), the high-strength security filter (4), the plasma reactor (5), liquid mist humidifier (6), catalytic reaction net (7), adsorption reaction net (9) and ultraviolet lamp group (8) are all arranged in the main body of the equipment structure, and the air inlet flange (1) and the air outlet flange (3) are respectively arranged at the two ends of the main body of the equipment structure. 3. The device for treating organic waste gas according to claim 2, characterized in that: the equipment structure main body adopts equipment steel structure main body (2). 4. The device for treating organic waste gas according to any one of claims 1 to 3, characterized in that: the high-strength security filter (4) is made of composite material fibers with a thickness of 5-10 cm. 5. The device for treating organic waste gas according to any one of claims 1 to 3, characterized in that: the plasma reactor (5) adopts pulsed corona discharge or wire-barrel corona discharge, and is perpendicular to the air inlet direction (11).