Double-aeration circulating type gas-liquid mixed dielectric barrier discharge wastewater degradation device

Abstract

The invention discloses a double-aeration circulating type gas-liquid mixed dielectric barrier discharge wastewater degradation device. The device comprises a double-aeration circulating type gas-liquid mixed dielectric barrier discharge reactor, a high-voltage alternating current power supply, a peristaltic pump, a flow controller and a gas generator, the reactor comprises a discharge area and a rear area; the discharge area is provided with a dielectric tube and a high-voltage electrode which are coaxial, and the gap is a gas discharge area; the space between the medium pipe and the container 1 is used for storing a wastewater solution; a check valve and a microporous aeration head are arranged at an outlet of the medium pipe; the rear area comprises an aeration disc and a container 2; according to the device, gas enters the discharge area to generate active substances, primary gas-liquid mixing is performed through the microporous aeration head, then the gas flows out of the reactor, enters the aeration disc, is subjected to secondary mixing and then is discharged, and a wastewater solution is circularly degraded in the reactor through the peristaltic pump. The method has the advantages of capability of degrading large-volume wastewater, low electrode corrosion rate, high energy utilization rate and the like.

Description

Technical Field

[0001] The invention patent relates to the field of plasma discharge for wastewater treatment, and specifically to a reaction device and method for degrading wastewater by generating active substances using gas-liquid two-phase discharge. Background Art

[0002] Water pollution has become one of the major livelihood issues threatening public health. Among them, organic wastewater discharged from the printing and dyeing industry has become a difficult problem in the field of industrial wastewater treatment due to its high chromaticity, complex chemical composition, biological toxicity and heavy metal components. Low-temperature plasma technology has shown significant technical advantages and engineering application potential in the field of printing and dyeing wastewater treatment due to its technical advantages such as good discharge stability, mild reaction conditions and high pollutant degradation rate. Dielectric barrier discharge (DBD) is a typical form of non-equilibrium discharge. It can generate O under normal pressure discharge conditions. 3 , active oxygen free radicals (O*) and other strong oxidizing substances. These active substances generate hydrogen peroxide (H 2 O 2 ) and hydroxyl radicals (·OH), which in turn trigger the mineralization and decomposition of organic pollutants in wastewater. The current DBD system still faces the technical bottleneck of limited gas-liquid two-phase mass transfer rate in practical applications, which restricts the large-scale application of this technology in the field of wastewater treatment. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention provides a double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device, which is used for the occurrence of DBD discharge and for the efficient degradation treatment of wastewater. The device can realize the functions of double aeration and water circulation, and can significantly improve the gas-liquid two-phase mass transfer rate through the double aeration and water circulation. At the same time, the water circulation can keep the device temperature at room temperature, so as to realize the stable operation of the device.

[0004] To achieve the above objectives, the present invention adopts the following technical solutions:

[0005] The double-aeration circulating gas-liquid mixed dielectric barrier discharge reaction device mainly includes three aspects: a discharge zone, a post-zone and a peristaltic pump; wherein the discharge zone includes a high-voltage electrode, a dielectric tube, a ground electrode, a container 1, a check valve, and a microporous aeration head; the dielectric tube is sleeved outside the high-voltage electrode, and the gap between the two is a gas discharge zone; the space between the inner wall of the container 1 and the outer wall of the dielectric tube is used to store wastewater solution; the ground electrode is located on the inner wall side of the container 1; the high-voltage electrode and the wastewater solution are separated by a check valve and a microporous aeration head; the post-zone includes an aeration plate and a container 2, which are used to store wastewater solution; the aeration plate is located at the bottom of the container 2; the gas is aerated twice through the microporous aeration head and the aeration plate to fully mix the active substance with the wastewater solution; the wastewater solution is circulated and degraded in the discharge zone and the post-zone through the peristaltic pump.

[0006] The device is a DBD discharge in the form of water electrode grounding generated under the excitation of a high-frequency AC power supply. The frequency of the high-voltage AC power supply is 0-20kHz, and the voltage of the high-voltage AC power supply is 1-60kV.

[0007] The device can perform two aerations through a microporous aeration head and an aeration plate. The microporous aeration head is located in the discharge zone, and the aeration plate is located in the rear zone.

[0008] The device can make the wastewater solution circulate in the reactor through a peristaltic pump.

[0009] The check valve is located at the outlet of the medium pipe, and the microporous aeration head is located at the outlet of the check valve.

[0010] The gas inlet is located in the medium pipe, and the gas outlet is located in the container 1.

[0011] The liquid inlet and outlet are both located in the container 1 .

[0012] The dielectric tube material is dielectric materials such as quartz and glass.

[0013] The container 1 and the container 2 are cylindrical and made of corrosion-resistant materials; the high-voltage electrode is a conductive metal rod, and the grounding electrode is a corrosion-resistant conductive metal tube.

[0014] The present invention provides a double-aeration circulation type gas-liquid mixed medium barrier discharge reaction device, which has the following advantages:

[0015] 1. Since ROS can only act on a small part of the wastewater at the gas-liquid contact surface, it has no obvious effect on the wastewater far from the contact surface. This patent improves the gas-liquid two-phase mass transfer rate through double aeration and water circulation functions. The peristaltic pump makes the wastewater solution circulate in the reactor, and the large number of microbubbles generated by the two aerations combined with the microporous aeration head and the aeration disk form a complex water flow movement in the reactor. This dynamic environment significantly improves the gas-liquid two-phase mass transfer rate.

[0016] 2. The check valve and microporous aeration head can prevent the liquid from flowing back into the medium pipe, realizing the physical isolation of the high-voltage electrode and the wastewater solution, thereby avoiding the contamination of the electrode by the wastewater solution and ensuring the long-term stable operation of the high-voltage electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0018] Figure 1 This is a structural diagram of the double-aeration circulating gas-liquid mixed medium barrier discharge reaction device of the present invention.

[0019] In the figure: 1. high voltage electrode, 2 medium tube, 3. container 1, 4. ground electrode, 5. gas inlet, 6. solution outlet, 7. check valve, 8. microporous aeration head, 9. solution inlet, 10. gas outlet, 11. fixing and sealing materials, 12. aeration disk, 13. container 2, 14. peristaltic pump, 15. gas discharge area.

[0020] Specific implementation cases

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. It is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0022] Refer to the attached Figure 1 A double-aeration circulating gas-liquid mixed dielectric barrier discharge reaction device comprises a high-voltage electrode (1), a dielectric tube (2), a container 1 (3), a ground electrode (4), a gas inlet (5), a solution outlet (6), a check valve (7), a microporous aeration head (8), a solution inlet (9), a gas outlet (10), fixing and sealing materials (11), an aeration plate (12), a container 2 (13), a peristaltic pump (14), and a gas discharge zone (15).

[0023] like Figure 1As shown, a double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device structure diagram, the device is divided into a discharge zone and a post-placement zone, the discharge zone from the inside to the outside are respectively a high-voltage electrode, a dielectric tube, a check valve, a microporous aeration head, a ground electrode, a container 1, and fixing and sealing materials. The post-placement zone includes an aeration plate and a container 2. The gas generator is connected to the flow controller, the flow controller is connected to the reactor, the reactor and the peristaltic pump are connected in sequence through the pipeline, and the air tightness of the device is checked. The high-voltage AC power supply is connected to the high-voltage electrode and the ground electrode of the reactor, and then the wastewater solution is added to the container 2, and then the peristaltic pump is turned on to make the wastewater solution circulate in the reaction device, and then the gas generator generates gas, and the flow controller controls the flow rate to inject a certain flow rate of gas into the reaction device, and finally the power is turned on for discharge to make the gas generate active substances, and the active substances are fully mixed with the wastewater solution through double aeration and water circulation, so that the wastewater solution is circulated and degraded in the reactor.

[0024] The device is a DBD discharge in the form of water electrode grounding generated under the excitation of a high-frequency AC power supply. The frequency of the high-voltage AC power supply is 0-20kHz, and the voltage of the high-voltage AC power supply is 1-60kV.

[0025] The device can perform two aerations through a microporous aeration head and an aeration plate. The microporous aeration head is located in the discharge zone, and the aeration plate is located in the rear zone.

[0026] The device can make the wastewater solution circulate in the reactor through a peristaltic pump.

[0027] The check valve is located at the outlet of the medium pipe, and the microporous aeration head is located at the outlet of the check valve.

[0028] The gas inlet is located in the medium pipe, and the gas outlet is located in the container 1.

[0029] The liquid inlet and outlet are both located in the container 1 .

[0030] The dielectric tube material is dielectric materials such as quartz and glass.

[0031] The container 1 and the container 2 are cylindrical and made of corrosion-resistant materials; the high-voltage electrode is a conductive metal rod, and the grounding electrode is a corrosion-resistant conductive metal tube.

[0032] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A double aeration circulation type gas-liquid mixed medium barrier discharge wastewater degradation device, characterized in that The device comprises: a double-aeration circulation gas-liquid mixed medium barrier discharge reactor, a high-voltage AC power supply, a peristaltic pump, a flow controller and a gas generator. The reactor is a double-aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device, characterized in that the device is divided into a discharge zone and a post-zone, and the discharge zone is respectively composed of a high-voltage electrode, a dielectric tube, a microporous aeration head, a check valve, a ground electrode, and a container 1 from the inside to the outside; the microporous aeration head and the check valve are located at the outlet of the dielectric tube, and the dielectric tube is sleeved outside the high-voltage electrode, and the gap between the two is a gas discharge zone, and the space between the inner wall of the container 1 and the outer wall of the dielectric tube is used to store the wastewater solution, and the ground electrode is located on the inner wall side of the container 1, and the wastewater solution and the gas are separated by the microporous aeration head and the check valve. The post-zone includes an aeration plate and a container 2, which are used to store the wastewater solution, and the aeration plate is located at the bottom of the container 2. The gas enters the gas discharge zone from the air inlet to generate active substances, and the active substances are mixed with the wastewater solution through the microporous aeration head, and then the gas flows out of the reactor and enters the aeration plate for secondary aeration to fully mix the active substances with the wastewater solution, and the wastewater solution is circulated and degraded in the reactor through a peristaltic pump.

2. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The device is a DBD discharge in the form of water electrode grounding generated under the excitation of a high-frequency AC power supply. The frequency of the high-voltage AC power supply is 0-20kHz, and the voltage of the high-voltage AC power supply is 1-60kV.

3. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The device can perform two aerations through a microporous aeration head and an aeration plate. The microporous aeration head is located in the discharge area, and the aeration plate is located in the rear area.

4. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The device can make the wastewater solution circulate in the reactor through a peristaltic pump.

5. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The check valve is located at the outlet of the medium pipe, and the microporous aeration head is located at the outlet of the check valve.

6. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The gas inlet is located in the medium pipe, and the gas outlet is located in the container 1.

7. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The liquid inlet and outlet are both located in the container 1 .

8. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The dielectric tube material is dielectric materials such as quartz and glass.

9. A double aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in claim 1, characterized in that The container 1 and the container 2 are cylindrical and made of corrosion-resistant materials; the high-voltage electrode is a conductive metal rod, and the grounding electrode is a corrosion-resistant conductive metal tube.

10. A method for treating wastewater using a double-aeration circulation type gas-liquid mixed dielectric barrier discharge reaction device as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: Connect the gas generator to the flow controller, the flow controller to the reactor, the reactor to the peristaltic pump in turn through pipelines and check the air tightness of the device; connect the high-voltage AC power supply to the high-voltage electrode and the ground electrode of the reactor, and set up a voltage and current monitoring device. Step 2: Generate gas through a gas generator, control the flow rate through a flow controller to inject gas at a certain flow rate into the reaction device, aerate through a microporous aeration head and an aeration disk, circulate the wastewater solution in the reactor through a peristaltic pump, and generate low-temperature plasma through discharge of a high-voltage AC power supply.

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