Disclosure of Invention
According to the technical problems that the prior DBD reactor structural design has the defects of poor discharge uniformity, poor stability, short electrode service life, high energy consumption and the like, the invention provides a liquid electrode dielectric barrier discharge reactor structural design. The invention mainly replaces the metal external net in the DBD technology reactor structure by constructing the liquid grounding electrode solution cavity filling liquid grounding electrode, and simultaneously plays the role of improving the performance indexes of DBD discharge uniformity, stability, strength, electrode service life, system energy consumption and the like by constructing the multi-scheme sectional conductive electrode.
The invention adopts the following technical means:
The liquid electrode dielectric barrier discharge reactor comprises a high-voltage electrode, wherein the high-voltage electrode is made of high-conductivity materials such as red copper, stainless steel, aluminum alloy or tungsten;
The outer side of the high-voltage electrode is sleeved with a conductive metal ring, and the conductive metal ring is made of a metal material with high conductivity.
The high-voltage electrode is characterized in that first insulating medium rings are respectively arranged at two ends of the conductive metal ring, and the first insulating medium rings are made of polytetrafluoroethylene, polyether-ether-ketone, quartz glass or ceramic and other materials with high breakdown field strength.
The conductive metal ring and the first insulating medium ring are positioned in the inner dielectric layer and tightly wrapped by the inner dielectric layer, and the inner dielectric layer can prevent the high-voltage electrode, the conductive metal ring and the first insulating medium ring from being corroded. The inner dielectric layer is made of polytetrafluoroethylene, quartz glass or ceramic, and is in a circular tube shape;
An outer dielectric layer is sleeved on the outer side of the inner dielectric layer, and the outer dielectric layer is made of quartz glass with high light transmittance. The outer dielectric layer is tightly attached to the liquid grounding electrode solution cavity, liquid electrode solution is arranged in the liquid grounding electrode solution cavity, and the liquid electrode solution forms a grounding electrode. The liquid ground electrode solution cavity is provided with a solution electrode inlet and a solution electrode outlet, and the liquid electrode solution circulates in the liquid ground electrode solution cavity through a water pump. The liquid electrode solution can adopt salt solution with high conductivity such as NaCl, KCL or KOH, and the conductivity is controlled by adjusting the concentration of the salt solution. The thickness of the outer dielectric layer, the volume of the liquid ground electrode solution chamber and the flow rate of the liquid solution are adjusted as required. The outer dielectric layer and the liquid grounding electrode solution cavity are of an integral design, so that the size of the reactor is reduced.
The plasma discharge device comprises an inner dielectric layer, an outer dielectric layer, a high-voltage electrode, a fastening sleeve and a coaxial cable, wherein a plasma discharge area for gas discharge is arranged between the inner dielectric layer and the outer dielectric layer, the two ends of the high-voltage electrode are respectively fixed with the fastening sleeve, the fastening sleeve seals the plasma discharge area, and the fastening sleeve is fixed with the high-voltage electrode and ensures the coaxiality of the fastening sleeve and the high-voltage electrode.
One end of the high-voltage electrode penetrates through the fastening sleeve and is connected with the high-voltage terminal of the plasma power supply to serve as a high-voltage excitation electrode, and after the power supply is connected, the working medium gas in the plasma discharge area is purified and converted.
The fastening sleeve is axially provided with a plurality of discharge area observation holes. The two fastening sleeves are axially provided with a gas inlet and a gas outlet which are communicated with the plasma discharge area. The fastening sleeve is made of polytetrafluoroethylene.
The conductive metal ring is an integral conductive metal ring, or the conductive metal ring is a split conductive metal ring, and the split conductive metal ring comprises at least two sub-conductive metal rings and a second insulating medium ring arranged between two adjacent sub-conductive metal rings. The thickness of the second insulating medium ring is regulated according to the actually applied excitation voltage range, so that the breakdown discharge of the high-voltage electrode and the grounding electrode is prevented.
The combination mode of the sub-conductive metal rings and the second insulating medium rings is that the sum of the lengths of all the sub-conductive metal rings is a constant value, the lengths of all the second insulating medium rings are the same, the insulation interval is the same, and the number of the sub-conductive metal rings is variable.
Or the combination mode of the sub-conductive metal rings and the second insulating medium ring is that the sum of the lengths of all the sub-conductive metal rings is a constant value, the number of the sub-conductive metal rings is a constant value, and the length of the second insulating medium ring is a variable.
The sectional electrode design scheme has the advantages of compact structure, metal material saving, multiple combinations, convenience in assembly and the like. Based on different application fields and specific application scenes, different segmentation combination modes can be adopted. Meanwhile, a plurality of groups of discharge rings are connected in parallel with one high-voltage terminal, so that the uniformity and the intensity of discharge can be effectively improved. The performance indexes such as the service life of the stable electrode of DBD discharge, the energy consumption of the system and the like are greatly improved.
Compared with the prior art, the invention has the following advantages:
The invention solves a series of problems brought by the metal outer net electrode in the DBD technology reactor structure in the prior art by constructing the liquid ground electrode solution cavity filling liquid ground electrode to replace the metal outer net electrode in the DBD technology reactor structure, secondly, the sectional type discharge structure design can realize that one high-voltage terminal is connected with a plurality of groups of discharge rings in parallel, thereby effectively improving the discharge uniformity and strength, in addition, the structural design of the inner dielectric layer and the outer dielectric layer can effectively avoid the corrosion of the metal electrode, thereby improving the suitable service life and the discharge stability of the discharge reactor, and finally, the design of the multi-scheme sectional type discharge structure has important significance for exploring the general rule of the optimal electrode ring number and the insulation interval length and has important value for promoting the wide application of the dielectric barrier discharge technology in a plurality of fields.
In summary, by adopting the technical scheme of the invention, the liquid grounding electrode is filled in the liquid grounding electrode solution cavity to replace the metal outer net electrode in the reactor structure of the DBD technology, and the problems of low DBD discharge uniformity, poor stability, low strength, short electrode service life, high system energy consumption and the like in the prior art are solved by constructing the multi-scheme sectional type liquid electrode.
Based on the reasons, the invention can be widely popularized in the fields of dielectric barrier discharge reactor structural design and the like.
Detailed Description
It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other. The invention will be described in detail below with reference to the drawings in connection with embodiments.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present invention. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be clear that the dimensions of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the authorization specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.
In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "axial, radial", "transverse, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, and are merely for convenience of describing the present invention and simplifying the description, and these azimuth terms do not indicate or imply that the apparatus or elements to be referred to must have a specific azimuth or be constructed and operated in a specific azimuth, without intending to limit the scope of the invention in that the azimuth terms "inside and outside" refer to inside and outside with respect to the outline of each component itself.
Spatially relative terms, such as "above," "upper" and "upper surface," "above" and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the process is carried out, the exemplary term "above" may be included. Upper and lower. Two orientations below. The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present invention.
Example 1
As shown in FIG. 1, the invention provides a liquid electrode dielectric barrier discharge reactor, which comprises a high-voltage electrode 5, a high-voltage electrode and a liquid electrode, wherein the high-voltage electrode adopts a bolt rod type structure and is provided with external threads, and the high-voltage electrode 5 is made of high-conductivity materials such as red copper, stainless steel, aluminum alloy or tungsten;
The outer side of the high-voltage electrode 5 is sleeved with a conductive metal ring 7, and the conductive metal ring 16 is made of a high-conductivity metal material. The high-voltage electrode 5 is provided with first insulating medium rings which are in threaded fit with the conductive metal rings 7 at two ends of the conductive metal rings, wherein the first insulating medium rings are respectively a left first insulating medium ring 6 and a right first insulating medium ring 8, and the first insulating medium rings are made of materials such as polytetrafluoroethylene, polyether ether ketone, quartz glass or ceramic with high breakdown field strength.
The conductive metal ring 7 is an integral conductive metal ring 7
The conducting metal rings 16 and the second insulating medium rings 17 are in threaded fit with the high-voltage electrode 5, and insulation is carried out by adopting a plurality of conducting metal rings 16 and the second insulating medium rings 17, so that the sectional arrangement of the conducting metal ring group 7 is realized;
The conductive metal ring 7, the left first insulating medium ring 6 and the right first insulating medium ring 8 are located in the inner dielectric layer 9 and are tightly wrapped by the inner dielectric layer 9, and the inner dielectric layer 9 can prevent the high-voltage electrode 5, the conductive metal ring 7 and the first insulating medium ring 6 from being corroded. The inner dielectric layer 9 is made of polytetrafluoroethylene, quartz glass or ceramic, and the inner dielectric layer 9 is in a circular tube shape;
An outer dielectric layer 11 is sleeved on the outer side of the inner dielectric layer 9, and the outer dielectric layer 11 is made of quartz glass with high light transmittance. The outer dielectric layer 11 is provided with a liquid grounding electrode solution cavity 12, the liquid grounding electrode solution cavity 12 is internally provided with a liquid electrode solution, and the liquid electrode solution forms a grounding electrode. The liquid ground electrode solution chamber 12 has a solution electrode inlet 3 and a solution electrode outlet 4, and the liquid electrode solution is circulated in the liquid ground electrode solution chamber 12 by a water pump. The liquid electrode solution can adopt salt solution with high conductivity such as NaCl, KCL or KOH, and the conductivity is controlled by adjusting the concentration of the salt solution. The thickness of the outer dielectric layer 11, the volume of the liquid ground electrode solution chamber 12, and the flow rate of the liquid solution are adjusted as needed. The outer dielectric layer 11 and the liquid ground electrode solution cavity are of an integral design, so that the size of the reactor is reduced.
A plasma discharge zone 10 for plasma discharge is provided between the inner dielectric layer 9 and the outer dielectric layer 11, the discharge gap dimension being of the order of mm. The two ends of the high-voltage electrode 5 are respectively fixed with a fastening sleeve, as shown in fig. 1, which is respectively a left fastening sleeve 13 and a right fastening sleeve 15. The left fastening sleeve 13 and the right fastening sleeve 15 seal the ion body discharge area 10, and the left fastening sleeve 13 and the right fastening sleeve 15 are fixed with the high-voltage electrode 5 through threads and ensure the coaxiality of the high-voltage electrode.
The left end of the high-voltage electrode 5 passes through the left fastening sleeve 13 and is connected with a high-voltage terminal of a plasma power supply to serve as a high-voltage excitation electrode, and the working medium gas in the plasma discharge region 10 is purified and converted after the power supply is connected.
The left fastening sleeve 13 is provided with a plurality of discharge area observation holes 14 in the axial direction. The right fastening sleeve 15 is axially provided with a gas inlet 1 communicated with the plasma discharge area 10, and the left fastening sleeve 13 is axially provided with a gas outlet 2 communicated with the plasma discharge area 10. The left fastening sleeve 13 and the right fastening sleeve 15 are made of polytetrafluoroethylene.
In a preferred embodiment of the invention, the conductive metal rings and the insulating medium rings are combined in a staggered manner, and under the condition that the total discharge length is consistent, a plurality of combination modes of different numbers of conductive metal rings with equal insulating interval lengths and different insulating interval lengths with equal conductive metal rings can be realized. The sectional electrode design scheme has the advantages of compact structure, metal material saving, multiple combinations, convenience in assembly and the like. Based on different application fields and specific application scenes, different segmentation combination modes can be adopted.
Example 2
As shown in fig. 1-2, the difference between this embodiment and embodiment 1 is that the conductive metal ring 7 is a split conductive metal ring, which includes at least two sub-conductive metal rings 16 and a second insulating medium ring 17 disposed between two adjacent sub-conductive metal rings 16. The second insulating medium ring 17 is made of polytetrafluoroethylene, polyether-ether-ketone, quartz glass or ceramic and other materials with high breakdown field strength, and the thickness of the second insulating medium ring 17 is adjusted according to the actually applied excitation voltage range to prevent the breakdown discharge of the high-voltage electrode 5 and the grounding electrode.
The combination of the sub-conductive metal rings 16 and the second insulating medium rings 17 is that the sum of the lengths of all the sub-conductive metal rings 16 is constant, the lengths of all the second insulating medium rings 17 are the same, the same insulating interval is achieved, the number of the sub-conductive metal rings 16 is variable, as shown in fig. 2, the number of the sub-conductive metal rings 16 is sequentially changed from two to five, the individual lengths of the sub-conductive metal rings 16 are gradually reduced, but the sum of the lengths of all the sub-conductive metal rings 16 is equal to the length of the integral conductive metal ring 7 mentioned in embodiment 1.
Example 3
As shown in fig. 1 and 3, this embodiment is different from embodiment 1 in that the conductive metal ring 7 is a split conductive metal ring including at least two sub-conductive metal rings 16 and a second insulating medium ring 17 disposed between adjacent two sub-conductive metal rings 16. The second insulating medium ring 17 is made of polytetrafluoroethylene, polyether-ether-ketone, quartz glass or ceramic and other materials with high breakdown field strength, and the thickness of the second insulating medium ring 17 is adjusted according to the actually applied excitation voltage range to prevent the breakdown discharge of the high-voltage electrode 5 and the grounding electrode.
The combination mode of the sub-conductive metal rings 16 and the second insulating medium rings 17 is that the sum of the lengths of all the sub-conductive metal rings 16 is a constant value, the number of the sub-conductive metal rings 16 is a constant value, and the length of the second insulating medium rings 17 is a variable value. As shown in fig. 3, the number of the sub-conductive metal rings 16 is five, and the length of the second insulating medium ring 17 increases sequentially from top to bottom, i.e. the insulating interval increases gradually.
In both the embodiment 2 and the embodiment 3, the conductive metal rings adopt a sectional discharge structure, which realizes that one high-voltage terminal is connected with a plurality of groups of discharge rings in parallel, so that the uniformity and the intensity of discharge can be effectively improved. The sectional electrode design scheme has the advantages of compact structure, metal material saving, multiple combinations, convenience in assembly and the like. Based on different application fields and specific application scenes, different segmentation combination modes can be adopted. Meanwhile, performance indexes such as DBD discharge uniformity, stability, strength, electrode life, system energy consumption and the like are greatly improved.
As shown in fig. 4, the graph of the influence data of the electrode structure on the discharge power density and the denitration efficiency in the present embodiment is analyzed. Fig. 4a shows electrode structures under different reactors, wherein electrode a is a one-stage high voltage electrode in a conventional bimetallic electrode reactor, and electrodes B (example 1), C (in example 2, with five sub-discharge metal rings) and D (in example 3, with the largest insulation gap at the bottommost end) are all high voltage electrodes in a liquid grounded electrode reactor. Fig. 4b shows the effect of different electrode conditions on the discharge power density. At the same input voltage, electrode a requires the greatest power density for discharge and the greatest energy consumed by discharge. The sectional electrode C designed by the invention has smaller power density required by discharge, and the discharge power density of the electrode D is further reduced along with the increase of the insulation interval. Taking denitration as an example, the effect of the electrode structure on the denitration efficiency is shown in fig. 4c. Compared with the traditional bimetal electrode structure, the sectional liquid ground electrode in the embodiment has higher denitration efficiency. Compared with the one-section electrode, the sectional electrode denitration efficiency is improved remarkably, and the denitration efficiency is further increased along with the increase of the insulation interval.
The above embodiments cover substantially all segmented electrode structures by taking control variable methods. The DBD reactor structure can be used in various application fields such as waste gas treatment, methane reforming, CO 2 conversion, catalyst preparation and the like, and the optimal sectional electrode DBD reactor is designed according to the practical application field and specific conditions by referring to the invention.
It should be noted that the above embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.