A dielectric barrier discharge reaction device and a dielectric barrier discharge water treatment method

Abstract

The present invention discloses a dielectric barrier discharge reaction device and a dielectric barrier discharge water treatment method, belonging to the technical field of wastewater treatment. The present invention includes a water tank and a reactor provided at the bottom of the water tank. A plurality of electrode plates are provided in the reactor. Dielectric layers are provided on the sides of the electrode plates opposite to each other. A reaction chamber is formed between the dielectric layers. A plurality of baffle plates are arranged in a hierarchical and staggered manner from top to bottom in the reaction chamber. The arrangement and arrangement mode of the baffle plates divide the reaction chamber to form a water flow channel. An inlet communicating with the water tank is provided at the top of the reaction chamber, and an outlet is provided at the bottom. Wastewater flows into the reactor from the inlet, forms a reciprocating downward flowing water flow through the water flow channel, and finally discharges from the outlet. An air outlet and an air inlet are respectively provided at the upper and lower parts of the reaction chamber. The air inlet and the air outlet are provided at the two farthest ends of the water flow channel. The present invention can treat wastewater with high degradation difficulty and high cost, and has the advantages of high efficiency, continuity and large treatment capacity.

Description

Technical Field

[0001] The present invention relates to wastewater treatment technology, and particularly to a dielectric barrier discharge reaction device and a dielectric barrier discharge water treatment method. Background Art

[0002] The components of pollutants such as industrial wastewater and waste gas are becoming increasingly complex, and the degradation difficulty is also continuously increasing. Using traditional treatment methods not only has a high cost, but also has problems such as being difficult to degrade and incomplete degradation leading to secondary pollution, and cannot meet the current environmental governance requirements. Currently, a plasma water treatment technology has gradually attracted people's attention due to its high degradation efficiency for pollutants.

[0003] Low-temperature dielectric barrier discharge (DBD), also known as silent discharge, is a gas discharge that inserts an insulating medium into the discharge space. When a high-voltage alternating current is applied to the discharge electrodes, the gas between the two electrodes is broken down to form dielectric barrier discharge and generate plasma. This technology can simultaneously generate active substances such as ozone, hydroxyl radicals, and ultraviolet photons during the water treatment process. Existing research shows that the low-temperature plasma technology has good effects in water treatment, waste gas treatment, and disinfection.

[0004] Currently, the common DBD reactor structures are plate type and cylindrical type. Most of the plate-type reactors are non-flowing batch reactors, with a small water treatment capacity, and only have a good treatment effect on the water film surface. When the water treatment depth is large, the degradation effect is often not obvious and the efficiency is low. The cylindrical reactor has a higher manufacturing cost than the plate type, and the reactor manufacturing process is more difficult. If the gap between the two electrodes is uneven, other forms of discharge are likely to occur. Due to the limitation of the discharge gap, the water treatment capacity of the cylindrical type is also small. Summary of the Invention

[0005] Therefore, in view of the defects existing in the above-mentioned prior art, the present invention provides a dielectric barrier discharge reaction device and a dielectric barrier discharge water treatment method, which can treat wastewater with high degradation difficulty and high cost, and have the advantages of high efficiency, continuity, and large treatment capacity.

[0006] To solve the above technical problems, the technical solutions adopted by the present invention are:

[0007] A dielectric barrier discharge reaction device, comprising a water tank for loading wastewater and a reactor provided at the bottom of the water tank. A plurality of electrode plates are provided in the reactor. Dielectric layers are provided on the opposite sides of the electrode plates facing each other. A reaction chamber is formed between the dielectric layers. A plurality of baffles are hierarchically and staggeredly arranged from top to bottom in the reaction chamber. The arrangement and arrangement method of the baffles divide the reaction chamber into water flow channels. An inlet communicating with the water tank is provided at the top of the reaction chamber, and an outlet is provided at the bottom. Wastewater flows into the reactor from the inlet, forms a reciprocating downward flowing water flow through the water flow channels, and finally discharges from the outlet. An air outlet and an air inlet are respectively provided at the upper and lower parts of the reaction chamber. The air inlet and the air outlet are provided at the two farthest ends of the water flow channel, so that the incoming gas flows the longest distance and then flows out from the air outlet, and an air flow is formed.

[0008] Further, the baffle can be horizontally arranged or inclined with a height difference at both ends, and the inclination directions of adjacent upper and lower baffles are opposite.

[0009] Further, the baffle has a wavy surface with ups and downs, so that when the water flow flows on the baffle, the contact area between the liquid film surface and the reaction substances is larger and the flow time is longer.

[0010] Further, the electrode plate is filled with copper powder, or a stainless steel mesh or other metal with high conductivity can be directly used. An electrode interface is provided on the electrode plate for power supply.

[0011] Further, there are three electrode plates, which are respectively arranged on the two side walls and in the middle of the reactor, forming two reaction chambers. While increasing the water treatment capacity, the cost is reduced by sharing the electrodes.

[0012] Further, the dielectric layer is any one of a ceramic layer, a rubber layer, and a quartz glass layer.

[0013] Further, a plurality of reactors are provided and are all connected in parallel with the water tank.

[0014] Further, a regulating valve is provided at the inlet of the reactor to regulate the water flow rate.

[0015] The present invention also provides a dielectric barrier discharge water treatment method. Using the dielectric barrier discharge reaction device, wastewater enters the water tank of the reaction device and flows into the reactor from the water inlet, and the water flow flows downward along the baffle plates; the electrodes are energized to apply high-voltage alternating current to the electrode plates in the reactor, causing the dielectric layer to break down and generate discharge, and releasing plasma in the reaction chamber; during this process, reaction gas is injected into the air inlet, and the gas can be oxygen, nitrogen or ordinary air, so that the gas flows upward reversely along the water flow channel. During this process, active substances such as ozone, hydroxyl radicals, and ultraviolet photons are generated. The wastewater fully contacts, mixes, and continuously reacts with the active substances, and then the gas is discharged from the air outlet, and the treated water is discharged from the water outlet to complete the wastewater treatment.

[0016] As can be seen from the above description of the structure of the present invention, compared with the prior art, the beneficial effects of the present invention are as follows: The wastewater enters the reactor from the water tank, and forms a relatively thin and turbulent flow under the action of the baffle plates layer by layer. Especially through the uneven wave-shaped surface on the baffle plates, the contact area between the surface of the wastewater liquid film and various active substances in the reaction chamber is increased, and the reaction time is prolonged; after the gas is filled into the air inlet, a gas-liquid two-phase discharge is formed in the reaction chamber, generating a plasma with a higher concentration. This not only increases the contact area between the reaction substances, but also when the gas is discharged from the air outlet, an air flow reverse to the water flow is formed, which also has a certain resistance effect on the water flow, can reduce the water flow speed, and makes the reaction more uniform and lasting; under the combined action of the baffle plates and the flowing gas, the active substances such as ozone, hydroxyl radicals, and ultraviolet photons generated in the reaction are transferred more fully and evenly between the water flow, the gas and the plasma, greatly enhancing the gas-liquid mass transfer efficiency between the reaction substances, and ultimately improving the reaction efficiency and water treatment effect.

[0017] This device can be set into reactors with different structures such as single-chamber double-electrode, two-chamber three-electrode, three-chamber four-electrode, etc. according to the application scenario and the amount of wastewater. Multiple reactors can also be connected in parallel under the wastewater tank, increasing the water treatment capacity and the scope of application, and having the ability to configure according to needs, so as to achieve the effect of reducing the use cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0019] Figure 1 is the front structural schematic diagram of the embodiment of the present invention;

[0020] Figure 2 is the side cross-sectional view of the embodiment of the present invention;

[0021] Reference numerals:

[0022] 1. Water tank; 2. Reactor; 21. Electrode plate; 22. Electrode; 23. Dielectric layer; 3. Reaction chamber; 31. Water inlet; 32. Water outlet; 33. Gas outlet; 34. Gas inlet; 4. Baffle plate. Detailed implementation manners

[0023] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0024] Embodiment 1

[0025] Reference Figure 1 And Figure 2 , a dielectric barrier discharge reaction device, comprising a water tank 1, a reactor 2 is provided at the bottom of the water tank 1, electrode grooves are provided on both side walls and the middle of the reactor 2, after the electrode grooves are filled with copper powder, electrode plates 21 are formed, electrodes 22 are provided on the electrode plates 21, dielectric layers 23 composed of quartz glass layers are respectively provided on the opposite side surfaces between the electrode plates 21, a reaction chamber 3 is formed between the dielectric layers 23, a plurality of baffle plates 4 with undulating wavy surfaces are provided in the reaction chamber 3 from top to bottom, the projections of adjacent upper and lower baffle plates in the plane are mutually misaligned and partially overlapped, and the arrangement of the baffle plates 4 forms a water flow channel to extend the flow time of water flow in the reaction chamber; the baffle plates 4 are arranged to incline downward, and the inclination directions of adjacent upper and lower baffle plates are opposite; a water inlet 31 communicating with the water tank is provided at the top of the reaction chamber 3, a water outlet 32 is provided at the bottom, and gas outlets 33 and gas inlets 34 are respectively provided on the upper and lower side walls of the reaction chamber 3 and at both ends of the water flow channel.

[0026] When using the dielectric barrier discharge reaction device, wastewater enters the water tank 1 of the reaction device, flows into the reactor 2 from the water inlet 31, and the water flow flows downward along the baffle plates 4; the electrodes 22 are energized to apply high-voltage alternating current to the electrode plates 21 in the reactor 2, the dielectric layers 23 are broken down to generate discharge, that is, dielectric barrier discharge is generated, and plasma is released in the reaction chamber 3; during this process, reaction gas oxygen is injected from the gas inlet 34, and the gas flows upward in reverse along the water flow channel, so that the water flow, gas and plasma are fully contacted, mixed and continuously reacted in the reaction chamber, then the gas is discharged from the gas outlet 33, and the reacted water is discharged from the water outlet 32 to complete the treatment of wastewater.

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

Claims

1. A dielectric barrier discharge reaction device, characterized in that: It includes a water tank and a reactor disposed at the bottom of the water tank. A plurality of electrode plates are provided in the reactor. A dielectric layer is provided on the side surface of the electrode plate opposite to the electrode plate. A reaction chamber is formed between the dielectric layers. A plurality of baffle plates are arranged in the reaction chamber in a staggered manner from top to bottom; an inlet communicating with the water tank is provided at the top of the reaction chamber, an outlet is provided at the bottom, and an air outlet and an air inlet are respectively provided at the upper and lower parts of the reaction chamber; the baffle plates are inclined, there is a height difference between the two ends of a single baffle plate, and the inclination directions of adjacent upper and lower baffle plates are opposite; the baffle plates have a wavy surface with ups and downs; the electrode plates are stainless steel meshes, and electrode interfaces are provided on the electrode plates.

2. The dielectric barrier discharge reaction device according to claim 1, characterized in that: There are three electrode plates, which are respectively arranged on the two side walls and in the middle of the reactor to form two reaction chambers.

3. The dielectric barrier discharge reaction device according to claim 1, wherein: The dielectric layer is any one of a ceramic layer, a rubber layer or a quartz glass layer.

4. The dielectric barrier discharge reaction device according to claim 1, wherein: A plurality of the reactors are provided and are connected in parallel with the water tank.

5. The dielectric barrier discharge reaction device according to claim 1, wherein: A regulating valve is provided at the inlet.

6. A dielectric barrier discharge water treatment method using the dielectric barrier discharge reaction device according to claim 1, characterized in that: Wastewater enters the water tank of the reaction device and flows into the reactor from the inlet. The water flow flows downward along the baffle plates; the electrodes are energized to apply a high-voltage alternating current to the electrode plates in the reactor. The dielectric layer breaks down to generate discharge, and plasma is released in the reaction chamber; during this process, reaction gas is injected into the air inlet to make the gas flow upward reversely along the water flow channel. The water flow, gas and plasma fully contact, mix and continuously react in the reaction chamber. Then the gas is discharged from the air outlet, and the treated water is discharged from the outlet to complete the treatment of wastewater.

7. According to the dielectric barrier discharge water treatment method described in claim 6, the reaction gas is any one of oxygen, nitrogen or air.

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