CN104276621A - Dam-type DBD (Dibromodulcitol) plasma wastewater treatment device of toothed electrode structure - Google Patents

Abstract

The invention discloses a dam-type DBD plasma wastewater treatment device with a tooth-shaped electrode structure, which includes an insulating base on which a plexiglass cylinder is installed, and a pair of inner electrodes are symmetrically arranged on the insulating base, and the outer sides of the two inner electrodes are respectively A pair of dielectric plates is provided, and the high-voltage electrodes are respectively clamped in the middle of the pair of dielectric plates. The sides of the two inner electrodes facing the corresponding pair of dielectric plates are respectively set in tooth-like concave-convex shapes. The top of the plexiglass cylinder and the top of the two pairs of dielectric plates are covered and installed. There is an upper cover, an inlet pipe and an outlet pipe are installed in the insulating base, an air inlet pipe is installed on the upper cover, and a power supply is provided. The invention can be used to treat high-concentration organic waste water.

Description

A dam type DBD plasma wastewater treatment device with toothed electrode structure

technical field

The invention relates to the field of plasma wastewater treatment devices, in particular to a dam type DBD plasma wastewater treatment device with a toothed electrode structure.

Background technique

With the development of industry, a large amount of industrial wastewater is produced and discharged, which has brought great pressure to environmental protection. Some industrial organic wastewater with simple components and easy biodegradation can be effectively treated by traditional combined processes such as physicochemical, chemical and biochemical, but for organic wastewater with high toxicity, high concentration and difficult biodegradation, the treatment effect is not ideal and the Dealing with high costs and other issues has become a major problem in terminal management.

The advanced oxidation process is an emerging technology in the field of sewage treatment in recent decades. It usually refers to the generation of highly reactive hydroxyl radicals (OH) under certain ambient temperature and pressure to oxidatively degrade organic pollutants that are difficult to treat with general oxidants. (Generally refers to organic substances with poor biodegradability, high concentration, complex composition, poisonous and harmful, which cannot be treated by general biochemical methods or cannot meet the treatment requirements). The same highly reactive hydroxyl radicals are more easily obtained by low-temperature plasma technology. Low-temperature plasma is rich in the above strong oxidizing components, which is an advanced oxidation treatment method. At the same time, the comprehensive effect of the components rich in low-temperature plasma can achieve better treatment of pharmaceutical wastewater.

The medium in the low-temperature plasma DBD discharge structure can effectively hinder the sharp increase of the current, and generate a stable low-temperature plasma under atmospheric pressure conditions (in the air). When there is oxygen in the discharge gas, it can generate abundant oxygen atoms and high levels such as ozone. Active particles and ultraviolet rays, these components have a positive impact on the degradation of organic matter; similarly, because of the presence of media, DBD discharge can treat industrial wastewater with high conductivity (pharmaceutical wastewater) without forming a short circuit; because of the existence of aqueous solution, plasma Strong oxidizing free radicals "OH ^· " will be produced in the body, these components have a positive impact on the degradation of organic matter, and can effectively treat pollutants in wastewater.

Patent No.: CN 101462021A discloses a dielectric barrier discharge low-temperature plasma harmful gas conversion device, which verifies the effect of DBD plasma on pollutants, but it is limited to the treatment of waste gas and has no application in wastewater treatment. Patent No.: CN101215027 A discloses a dielectric barrier discharge wastewater treatment device, and the wastewater treatment results are not ideal; The removal rate of nitenpyram waste liquid. However, this patent uses air as the discharge gas, and the discharge structure involved is to a large extent discharge to water, which will increase the discharge power and generate a lower concentration of active particles, thus weakening the effect of plasma on pollutants Effect. If the concentration of strong oxidizing components in the plasma can be effectively increased and the contact area between the plasma and wastewater can be increased, the treatment time can be greatly reduced.

The invention patent with the patent application number 201420014501.0 applied for "a new type of dam-type DBD plasma treatment of pharmaceutical industry wastewater technology". The dam-type DBD plasma involved means that the working gas is discharged in one-dimensional direction to form a uniform and stable Plasma can realize the characteristics of large-area treatment through linear arrangement or sample scanning, which can effectively improve the treatment efficiency of industrial wastewater and realize industrial amplification. The patent of the present invention will improve the density and intensity of the plasma on the basis of the dam type DBD plasma wastewater treatment device involved in the patent by changing the shape of the internal electrode, that is, setting the toothed electrode structure, so as to generate a higher concentration of active radicals. group, thereby improving the ability and efficiency of the dam-type DBD plasma wastewater treatment device to treat high-concentration organic wastewater.

SUMMARY OF THE INVENTION The object of the present invention is to provide a dam-type DBD plasma wastewater treatment device with a toothed electrode structure for treating high-concentration organic wastewater.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A dam-type DBD plasma wastewater treatment device with a toothed electrode structure, characterized in that it includes a horizontally arranged insulating base, a plexiglass cylinder is vertically installed on the insulating base, and the insulating base in the plexiglass cylinder is also symmetrically arranged There is a pair of inner electrodes, and the outer sides of the two inner electrodes are respectively provided with a pair of dielectric plates, and the middle of the pair of dielectric plates is respectively clamped with a high-voltage electrode. The top and the two dielectric plates cover the top with an upper cover, and the insulating base is installed with a water inlet pipe between the two inner electrodes, and the water inlet pipe is connected to between the two inner electrodes in the plexiglass cylinder, and the insulating base Water outlet pipes are respectively installed between each inner electrode and the corresponding pair of dielectric plates, and the water outlet pipes are respectively connected to each inner electrode in the plexiglass cylinder and the corresponding pair of dielectric plates. The cover is equipped with an air intake pipe, and the air intake pipe is connected to the top between the two medium board pairs, and the organic glass cylinder is filled with working gas through the air intake pipe, and also includes a power supply arranged outside the organic glass cylinder. The connecting head of the high-voltage electrode is connected to the power supply through a high-voltage wire, and the connecting head of the inner electrode is connected to the grounding terminal of the power supply through a grounding wire.

The dam-type DBD plasma wastewater treatment device with a toothed electrode structure is characterized in that: the insulating base is also provided with cooling channels between each pair of dielectric plates and the corresponding side organic glass cylinder wall. One end of the cooling through hole is connected to the plexiglass cylinder, and the other end of the cooling through hole is connected to the outside of the insulating base.

The dam-type DBD plasma wastewater treatment device with a toothed electrode structure is characterized in that: the power supply is a high-frequency high-voltage power supply, or a nano-fast pulse repetition frequency power supply, or a pulsed high-frequency high-voltage power supply.

The dam-type DBD plasma wastewater treatment device with a toothed electrode structure is characterized in that: the material of the inner electrode is a corrosion-resistant electrode or a copper electrode, the material of the high-voltage electrode is a copper electrode, and the medium plate is aligned with each medium The plate material is high temperature resistant glass or quartz glass.

The dam type DBD plasma wastewater treatment device with a toothed electrode structure is characterized in that: the working gas is air, or a mixture of air and an inert gas, or oxygen, or a mixture of oxygen and an inert gas .

The present invention has the following advantages:

1) The present invention provides a dam-type DBD plasma wastewater treatment device with a toothed electrode structure. The dam-type DBD plasma wastewater treatment device can isolate the high-voltage electrode from the treated wastewater, increase the intensity of the discharge, and increase the intensity of the plasma.

2) The process improves the efficiency of wastewater treatment by combining traditional wastewater treatment technology as a pre-treatment and post-treatment process for DBD plasma wastewater treatment;

3) The internal electrodes involved in the present invention can be corrosion-resistant electrodes (such as graphite), and the selection of corrosion-resistant electrodes can adapt to the treatment of various wastewater qualities.

4) The setting of the convex and concave surface of the tooth-shaped electrode involved in the present invention can effectively improve the discharge surface of the internal electrode. When discharging with the external electrode, the uneven discharge surface and the flat high-voltage electrode discharge can produce superposition, improve the discharge intensity and The generated plasma density; at the same time, the design of the structure can enhance the electric field intensity at the toothed electrode, thereby enhancing the discharge intensity at this place and increasing the concentration of active components generated there; at the same time, the toothed electrode further increases the plasma and solution level The contact area interacts with the plasma generated in the recess to improve the processing efficiency.

5) The technology of the present invention can produce a large area of uniform and stable dam-type plasma, which can also be called linear plasma. According to the different power sources used, pulsed or continuous plasma can be generated, and the length of the generated plasma can be adjusted. Up to 3m-10m, uniformity in one-dimensional direction can reach 80%-95%; through vertical arrangement, large-area processing capacity can be realized;

6) The heat generated by the discharge of the DBD plasma wastewater treatment device of the present invention can be cooled by heat exchange through the wastewater and the cooling medium;

7) The working gas used in the present invention can be air, inert gas doped with oxygen or inert gas doped with air, and high-energy active particles generated by oxygen discharge.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

Detailed ways

Referring to shown in Fig. 1, a dam type DBD plasma wastewater treatment device with a toothed electrode structure includes a horizontally arranged insulating base 109, and an organic glass cylinder 108 is vertically installed on the insulating base 109, and the organic glass cylinder 108 A pair of inner electrodes 103 are arranged symmetrically on the insulating base 109, and a pair of dielectric plates 107 are respectively arranged on the outer sides of the two inner electrodes 103. The pair of dielectric plates 107 holds a high-voltage electrode 105 respectively, and the two inner electrodes 103 face the corresponding pair of dielectric plates 107 respectively. The sides of the sides are respectively set in a tooth-like concave-convex shape, the top of the plexiglass cylinder 108 and the top of the two dielectric plates 107 are covered with an upper cover, and the insulating base 109 is located between the two inner electrodes 103. A water inlet pipe 111 is installed, and The water inlet pipe 111 is connected between the two inner electrodes 103 in the plexiglass cylinder 108, and the water outlet pipe 112 is respectively installed between each inner electrode 103 and the corresponding dielectric plate pair 107 in the insulating base 109, and the water outlet pipe 112 They are respectively connected between each inner electrode 103 in the plexiglass cylinder 108 and the corresponding pair of dielectric plates 107, and the upper cover is equipped with an air intake duct 110, and the air intake duct 110 is connected to the top between the two dielectric plate pairs 107, In the plexiglass cylinder 108, the working gas 202 is charged through the air inlet pipe 110, and the power supply 101 arranged outside the plexiglass cylinder 108 is also included. The connection head 104 of 103 is connected to the ground together with the ground terminal of the power supply 101 through the ground wire.

In the insulating base 109, cooling through holes 204 are respectively provided between each pair of dielectric plates and the wall of the organic glass cylinder 108 on the corresponding side. One end of the cooling through hole 204 is connected to the inside of the organic glass cylinder 108, and the other end of the cooling through hole 204 is connected. to the outside of the insulating base 109.

The power supply 101 adopts high-frequency high-voltage power supply, or adopts nanometer fast pulse repetition frequency power supply, or adopts pulse high-frequency high-voltage power supply.

The inner electrode 103 is made of corrosion-resistant electrode or copper electrode, the material of high-voltage electrode 105 is made of copper electrode, and the material of each dielectric plate in the dielectric plate pair is high-temperature-resistant glass or quartz glass.

The working gas 202 is air, or a mixture of air and an inert gas, or oxygen, or a mixture of oxygen and an inert gas.

The invention can work stably under the atmospheric pressure, effectively hinders the sharp increase of current through the medium in the DBD discharge, can generate stable low-temperature plasma under atmospheric pressure conditions (in air), and can generate abundant plasma when there is oxygen in the discharge gas Oxygen atoms and highly active particles such as ozone and ultraviolet rays, after being passed into the aqueous solution, components such as hydroxyl groups will be generated in the plasma. These high-energy particles or rays can interact with pollutants in wastewater, especially organic matter, metal ions, and bacteria. and microorganisms, so as to achieve the purpose of degrading organic matter and eliminating pollutants.

In the present invention, the plasma discharge chamber is composed of internal electrodes (including internal electrodes 103, internal electrode terminals 104), external electrodes (including high-voltage electrodes 105, high-voltage electrode terminals 106), dielectric plate pairs 107, insulating bases 109 and organic The glass cylinder 108 forms a cooling chamber 113 formed by the pair of dielectric plates 107 . In order to improve the processing efficiency, a symmetrical plasma discharge cavity is designed to form two plasma discharge regions.

In the present invention, the internal electrode is not a regular plate electrode, but the surface of the internal electrode 103 on the discharge side is provided in a tooth-like convex-convex shape. The setting of the tooth-shaped convex and concave surface can effectively improve the discharge surface of the internal electrode, and cooperate with the high-voltage electrode to discharge. The uneven discharge surface and the flat high-voltage electrode can enhance the local electric field intensity, improve the discharge intensity and the generated plasma density. ; At the same time, the design of the structure can increase the contact area between the plasma and the treatment liquid, so that the generated plasma can fully contact the aqueous solution in the recess.

In the present invention, the power supply 101 uses ns fast pulse (rising edge of 2~10ns, pulse width of 30~80ns, repetition frequency of 500~2000Hz) or high voltage AC power supply (peak voltage of 8~20Kv, 20~80kHz); the inner electrode can be 103 Copper electrodes are selected after corrosion-resistant electrodes, copper electrodes are selected for the high-voltage electrode 105, high-temperature-resistant glass or quartz glass can be used for the dielectric plate pair 107; insulating materials such as polytetrafluoroethylene, nylon, and epoxy resin can be used for the insulating base 109.

The waste water of the present invention enters the discharge chamber from the water inlet pipe 111, and a uniform and continuous water film 201 is formed on the surface of the inner electrode 103; the working gas 202 can be air, an inert gas (such as Ar gas) doped with oxygen, or an inert gas doped with air; Filamentous plasma is generated by discharge between the inner and outer electrodes to form a high-density plasma region 203; air cooling can be used to prevent the electrodes from overheating and damage components, or water cooling can be used, and the water cooling medium should be deionized water.

Implementation example:

The present invention takes the simulated wastewater (aqueous solution of the pesticide oxadiazone) as the treatment object, the initial concentration of the oxadiazone aqueous solution is 40 mg/L, and the initial COD value is 97280 mg/L.

The simulated wastewater was treated for 30 minutes by a dam-type DBD plasma wastewater treatment device with a planar inner electrode, and the COD value dropped to 33159 mg/L, with a degradation rate of about 65.9%. After 300 minutes of treatment, the COD value dropped to 4500 mg/L L, the degradation rate is about 95.3%;

After being treated by the dam type DBD plasma wastewater treatment device with toothed electrode structure of the present invention for 30 minutes, the COD value dropped to 15910, and the degradation rate reached 83.6%. After 300 minutes, the COD value dropped to 1500mg/L, and the degradation rate was about 98.5%, compared with the results of the internal electrode with a planar structure, the COD degradation is faster and more thorough. Therefore, the toothed electrode structure adopted in the present invention can significantly improve the COD value of the degraded wastewater. It can be said that the use of the toothed electrode structure improves the treatment effect and treatment efficiency of the dam-type DBD plasma wastewater treatment device.

Claims (5)

1. a dam type DBD plasma waste water treatment device of a toothed electrode structure, is characterized in that: comprise the insulating base that horizontal setting is arranged, on the insulating base vertically be equipped with plexiglass tube, on the insulating base in the plexiglass tube also A pair of inner electrodes are arranged symmetrically, and a pair of dielectric plates are respectively arranged on the outer sides of the two inner electrodes, and high-voltage electrodes are clamped in the middle of the pair of dielectric plates, respectively, and the sides of the two inner electrodes facing the corresponding pair of dielectric plates are respectively set in a tooth-like concave-convex shape, organic The top of the glass cylinder and the two dielectric plates are connected to the top and an upper cover is installed. A water inlet pipe is installed between the two inner electrodes in the insulating base, and the water inlet pipe is connected to the two inner electrodes in the plexiglass cylinder. Water outlet pipes are respectively installed between each inner electrode and the corresponding pair of dielectric plates in the insulating base, and the water outlet pipes are respectively connected to each inner electrode in the plexiglass cylinder and the corresponding pair of dielectric plates. The upper cover is equipped with an air intake pipe, and the air intake pipe is connected to the top between the two pairs of medium plates, and the plexiglass cylinder is filled with working gas through the air intake pipe, and also includes a power supply arranged outside the plexiglass cylinder. The terminal of the high-voltage electrode is connected to the power supply through a high-voltage wire, and the terminal of the inner electrode is connected to the ground terminal of the power supply through a grounding wire. 2. The dam type DBD plasma wastewater treatment device with toothed electrode structure according to claim 1, characterized in that: the insulating base is located between each pair of dielectric plates and the corresponding side plexiglass cylinder wall Cooling through holes are also respectively provided, one end of the cooling through hole is connected to the inside of the plexiglass cylinder, and the other end of the cooling through hole is connected to the outside of the insulating base. 3. The dam type DBD plasma wastewater treatment device with toothed electrode structure according to claim 1, characterized in that: said power supply adopts high-frequency high-voltage power supply, or adopts nanometer fast pulse repetition frequency power supply, or adopts pulse High frequency high voltage power supply. 4. The dam-type DBD plasma wastewater treatment device with toothed electrode structure according to claim 1, characterized in that: the material of the inner electrode is a corrosion-resistant electrode or a copper electrode, the material of the high-voltage electrode is a copper electrode, and the medium The material of each dielectric board in the board pair is high temperature resistant glass or quartz glass. 5. The dam type DBD plasma wastewater treatment device with toothed electrode structure according to claim 1, characterized in that: said working gas is selected from air, or a mixture of air and inert gas, or oxygen, or oxygen Mixed gas with inert gas.