CN202113752U - Nonequilibrium state plasma purifier - Google Patents

Abstract

A non-equilibrium plasma purifier belongs to the technical field of environmental pollution control. Including power supply, non-equilibrium plasma reactor and exhaust activated carbon adsorption purifier; discharge electrode and ground electrode are installed in the closed non-equilibrium plasma reactor, and the power supply and discharge electrode are connected through high-voltage wires, and the ground electrode is grounded through the ground wire The discharge electrode is perpendicular to the ground electrode, and the substrate is arranged parallel to the ground electrode in the non-equilibrium plasma reactor; the discharge electrode is installed on the surface of the substrate facing the ground electrode, and the discharge electrode is perpendicular to the substrate; it is close to the ground in the reactor There are two gas inlets on one side of the electrode, and the two gas inlets are distributed symmetrically up and down; two gas outlets are arranged symmetrically up and down on the side close to the base plate in the reactor; the two gas outlets are connected to the activated carbon adsorption and purification of exhaust gas at the same time. device. This type of reactor greatly improves the treatment efficiency of waste gas, and has simple structure, strong applicability and low operating cost.

Description

A non-equilibrium plasma purifier

technical field

The utility model relates to a pollutant purification treatment device aimed at the field of atmospheric control, in particular to a countercurrent non-equilibrium plasma reaction device, which belongs to the technical field of environmental pollution control.

Background technique

With the continuous expansion of human production activities and living activities, the components of exhaust pollutants discharged into the environment are complex, and the number of toxic and harmful substances is increasing. Not only has it caused serious damage to the ecological environment, but it has also brought immeasurable harm to human beings. The traditional waste treatment technology can no longer meet the needs, and the non-equilibrium plasma technology is attracting extensive attention in the research field because of its advantages of low development cost, thorough treatment, and no secondary pollution.

The main components in the exhaust gas are: total suspended particles, floating dust, sulfur oxides, nitrogen oxides, hydrogen sulfide, ammonia, carbon oxides and organic vapors (VOCs). They come from domestic pollution sources, industrial pollution sources and traffic pollution sources respectively. Common treatment technologies include: mechanical filtration, liquid adsorption, solid adsorption, electrostatic adsorption, catalytic conversion, etc. These technologies play an important role in the treatment of exhaust gas. However, with the complexity and concentration of exhaust gas components, the defects of these technologies, such as low efficiency, primary pollution, corrosion of equipment, complex process, large investment and high operating cost, are gradually revealed. The most dynamic exhaust gas treatment technology is the non-equilibrium plasma technology. The pulse discharge desulfurization and denitrification technology first proposed by Masnda S. in the late 1980s belongs to this technical category.

Suspended particles and floating dust in industrial waste gas are suspended in the air for a long time in gaseous state and aerosol state, causing serious pollution to the atmospheric environment. Among them, particles with a particle size between 0.1 and 5um are the most dangerous to the human body. Non-equilibrium plasma technology can effectively remove these particles in the exhaust gas. The treatment mechanism is: non-equilibrium plasma generated by non-uniform discharge (such as corona discharge), in which electrons and ions collide with particles in the exhaust gas under the action of gradient field and attach to these particles, making them Become charged particles, and then be collected by the dust collector.

The plasma treatment mechanism for other gaseous pollutants in the exhaust gas is as follows: the plasma generated by gas discharge contains a large number of high-energy electrons, ions, excited state particles and free radicals with strong oxidative properties, and the average energy of active particles is high. The bond energy of gas molecules. As a result of the collision between these active particles and harmful _molecules , on the one hand, the bonds of gas molecules are opened to generate some monatomic molecules and solid particles; ₃ . The chemical reaction caused by the active particles composed of these single-atom molecules, free radicals and _O3, etc., finally changes the harmful substances in the exhaust gas into harmless substances.

Utility model content

The purpose of the utility model is to provide a novel, effective and low energy consumption countercurrent needle plate type non-equilibrium plasma purification device.

The waste gas treatment device provided by the utility model combines corona discharge and dielectric barrier discharge to generate non-equilibrium plasma technology. The reactor is a pin-plate structure, and the pollutant gas flow is used to contact the non-equilibrium plasma channel countercurrently. form to degrade exhaust gas. The device has the advantages of simple structure, small footprint, wide application range and good treatment effect.

A non-equilibrium plasma purification device of the present utility model is characterized in that: a non-equilibrium plasma purification device is characterized in that it includes a power supply 5, a non-equilibrium plasma reactor 6 and an exhaust activated carbon adsorption purifier 10. Install the discharge electrode 1 and the ground electrode 2 in the non-equilibrium plasma reactor 6, connect the power supply 5 to the discharge electrode 1 through the high-voltage wire 8, and connect the ground electrode 2 to the ground through the ground wire 9; the discharge electrode 1 is perpendicular to the ground electrode 2. The discharge electrode 1 is a solid or hollow needle tip, solid or hollow metal rod or metal tube with a radius of curvature < 10 mm; the base plate 7 is a metal flat plate with a smooth surface, and the base plate 7 and the grounding electrode 2 are made of 3-5 mm thick steel plates. , the aperture is 40-60 mm, and the opening ratio is 50%-65%; the substrate 7 is arranged in the non-equilibrium plasma reactor 6 in parallel with the ground electrode 2; the discharge electrode is installed on the surface of the substrate 7 facing the ground electrode 2 1. The discharge electrode 1 is perpendicular to the substrate 7; the distance between the discharge electrode 1 and the ground electrode 2 is 1 cm to 12 cm; two gas inlets are arranged on the side close to the ground electrode 2 in the non-equilibrium plasma reactor 6 Inlet 3, two gas inlets 3 are distributed symmetrically up and down, and the overall structure of the non-equilibrium plasma reactor 6 is airtight; two gas outlets 4 are symmetrically arranged up and down on the side close to the base plate 7 in the non-equilibrium plasma reactor 6 ; The two gas outlets 4 are simultaneously connected to the exhaust activated carbon adsorption purifier 10.

The obvious difference between the non-equilibrium plasma purification device provided by the utility model and the existing non-equilibrium plasma purification device is:

A non-equilibrium plasma channel is formed between the discharge electrode 1 and the ground electrode 2, and the polluted gas entering the reactor 6 is in reverse contact with the non-equilibrium plasma channel, which increases the energy of high-energy electrons and strong oxidizing free radicals in the plasma channel. and the collision probability and collision rate of quasi-neutral molecules, thereby improving the utilization rate of plasma; the overall structure of the non-equilibrium plasma reactor 6 is sealed and operated, using the principle of a static pressure box, and the internal pressure of the purifier is balanced, which is beneficial to the gaseous state. The airflow and concentration of pollutants are stable; the exhaust gas purifier is used to achieve the complete and harmless discharge of pollutants and waste gas; at the same time, this device combines corona discharge and dielectric barrier discharge to avoid the generation of arc during discharge. Facilitate the generation of plasma active groups.

In short, this type of reactor greatly improves the efficiency of waste gas treatment, and has a simple structure, strong applicability, and low operating costs.

Using the purification device to purify VOCs gas, it is found that the purification effect of gaseous VOCs pollutants is increased by more than 15% compared with the general pin-plate reactor, and the dust removal effect is increased to more than 99.99%.

Description of drawings

Fig. 1 is the technological process schematic diagram of the present utility model.

Fig. 2 is a schematic diagram of the structure of the needle-plate electrode of the present invention.

Fig. 3 is a schematic diagram of the structure of the needle tube-plate electrode of the present invention.

In the figure, 1. Discharge electrode, 2. Ground electrode; 3. Air inlet, 4. Gas outlet, 5. Power supply, 6. Non-equilibrium plasma reactor, 7. Base plate, 8. High voltage wire, 9. Ground wire, 10. Exhaust gas purifier.

Detailed ways

The overall structure of the non-equilibrium plasma reactor 6 is sealed and operated, using the principle of the static pressure box, and the internal pressure of the purifier is balanced, which is conducive to the stability of the gas flow and concentration of gaseous pollutants; the discharge electrode 1 and the ground electrode 2 are needle plate type, and the discharge electrode 1 perpendicular to the grounding electrode 2, the needle-shaped discharge electrode 1 is a solid or hollow needle tip, solid or hollow metal rod or metal tube with a radius of curvature < 10mm, and the needle-shaped discharge electrode 1 is placed on the base plate 7; the base plate 7 is smooth When the discharge electrode 1 is solid, the incoming waste gas interacts with the non-equilibrium plasma, and the evenly distributed holes on the substrate 7 are discharged to the gas outlet 4 of the purification device 6, and finally discharged from the gas outlet 4; when the discharge electrode 1 When it is hollow, the substrate 7 has no holes, and the purified waste gas is discharged from the discharge electrode 1; the distance between the needle-shaped discharge electrode 1 and the plate-shaped ground electrode 2 is 6cm; the ground electrode 2 is grounded, and the grounding resistance is ≤4Ω.

The power supply 5 outputs high voltage, which is applied between the discharge electrode 1 and the ground electrode 2. Adjust the distance between the discharge electrode 1 and the ground electrode 2 and the peak value of the output voltage of the power supply 5, so that the electric field strength between the discharge electrode 1 and the ground electrode 2 reaches 8kV/ cm, a non-equilibrium plasma channel is formed between electrode 1 and electrode 2, and there are a large number of high-energy electrons, strong oxidizing groups and quasi-neutral molecules in the channel; Enter the purification device 6, contact with the plasma channel reversely, after fully reacting, it is discharged from the gas outlet 4 of the purification device 6; the exhaust gas is discharged into the atmosphere after passing through the additional exhaust gas purifier 10.

A certain amount of catalyst is attached to the surface of the electrode. The catalyst uses modified barium titanate Ba _0.8 Sr _0.2 Zr _0.1 Ti _0.9 O ₃ as the carrier, and metal oxides such as MnO ₂ /γ-Al ₂ O ₃ are loaded on the surface of the carrier as active components.

After the pollutant exhaust gas is purified by plasma, it passes through the additional exhaust gas purifier 10 to achieve the purpose of thorough purification. The tail gas purifier 10 adopts an activated carbon adsorption device.

Using the purification device to purify VOCs gas, it is found that the purification effect of gaseous VOCs pollutants is increased by more than 15% compared with the general pin-plate reactor, and the dust removal effect is increased to more than 99.99%.

Claims (1)

1. A non-equilibrium plasma purification device is characterized in that: comprise power supply (5), non-equilibrium plasma reactor (6) and tail gas activated carbon adsorption purifier (10); in non-equilibrium plasma reactor (6) discharge electrode (1) and ground electrode (2) are installed inside, the power supply (5) is connected to discharge electrode (1) through high voltage electric wire (8), and ground electrode (2) is grounded through ground wire (9); The electrode (1) is perpendicular to the ground electrode (2), the discharge electrode (1) is a solid or hollow needle tip, solid or hollow metal rod or metal tube with a radius of curvature < 10 mm; the base plate (7) is a smooth metal plate, the base Both the disc (7) and the ground electrode (2) are made of 3-5 mm thick steel plate, the aperture is 40-60 mm, and the opening ratio is 50%-65%; the base plate (7) is arranged in parallel with the ground electrode (2) The discharge electrode (1) is installed on the surface of the base plate (7) facing the ground electrode (2), and the discharge electrode (1) is perpendicular to the base plate (7); the discharge electrode (1) The distance between the ground electrode (2) and the ground electrode (2) is 1cm to 12cm; two air inlets (3) are provided on the side close to the ground electrode (2) in the non-equilibrium plasma reactor (6). The gas ports (3) are distributed symmetrically up and down, and the overall structure of the non-equilibrium plasma reactor (6) is airtight; in the non-equilibrium plasma reactor (6), two outlets are symmetrically arranged up and down on the side close to the substrate (7). The gas port (4); the two gas outlets (4) are simultaneously connected to the exhaust activated carbon adsorption purifier (10).

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