CN205657903U - Secondary coupling microwave plasma reforming unit - Google Patents

Abstract

The utility model discloses a secondary coupling microwave plasma reforming unit, include: the cavity, it is cylindrical cavity, the ring waveguide, it encircles and puts at cavity central point for separate the cavity for being located the cylinder resonator and outside annular reaction chamber that central point put, be provided with a plurality of circumferencial directions symmetry evenly distributed's coupling window on the ring waveguide, the microwave plasma reaction tube, it sets up in the central department of annular reaction chamber, and it has the air mixture to lead to in the microwave plasma reaction tube, the coupling device, it is quarter -wave resonance chamber coupling device, sets up inside the resonant cavity, the ignitor electrode, it includes two wires, connects high voltage power supply, sets up the intake port department at the microwave plasma gas reaction pipe, wherein, microwave energy can pass through the coupling device gets into in the cylinder resonator, the rethread the coupling window coupling gets into in the annular reaction chamber, multiport coupling simultaneously, coupling efficiency is high, and microwave energy distributes more evenly in the reaction chamber.

Description

A kind of secondary coupled microwave plasma reformer

Technical field

This utility model relates to microwave plasma field, particularly to a kind of secondary coupling microwaves plasma Body weight engagement positions.

Background technology

Microwave plasma reformer is to utilize microwave-excitation burning mixture to produce plasma, logical Cross plasma and promote burning mixture generation reforming reaction, produce hydrogen-rich gas, there is reaction yield High, without advantages such as catalyst.The mechanism of reforming plasma reaction is to utilize high energy electricity in plasma Neutral particle in son impact plasma, makes neutral particle occur cracking to produce active group (group), these Under certain condition, electronics reconfigures active group (group) with new atomic nucleus or cation, is formed new Molecule or atomic structure.Conventional chemical reaction is difficulty with or needs expensive heavy metal as catalyst The reaction that could realize, can be reacted by reforming plasma and realize easily.Therefore, plasma is reformed Reaction can make the fuel such as gasoline, ethanol be converted into hydrogen-rich combustion mixture for improving the burning of electromotor.

Low-temperature plasma is a kind of non-equilibrium plasma.In low temperature plasma, electron temperature is long-range In heavy particle temperature.Such benefit is that the bulk temperature of on the one hand plasma is the highest, can effectively subtract Heat radiation energy loss in few reforming process, improves the economical of reforming reaction, on the other hand electronics by In having higher movement velocity (in low temperature plasma, electron temperature is typically between 1eV～10eV), The collision frequency of electronics and heavy particle is the highest, beneficially chemical reaction.

Microwave plasma is a kind of preferably low temperature plasma, permissible by microwave heating plasma Allow reforming reaction is continual to be carried out.But, most critical for microwave plasma reforming reaction Being design microwave plasm reaction cavity, the quality of reaction chamber design directly determines the efficiency of reforming reaction And economy.In microwave plasm reaction cavity design process, need to consider the two of mixed gas simultaneously The state of kind, a kind of original state being plasma and being formed, this process plasma is also formed without can To be considered gaseous state, another kind of state is that mixed gas has been adequately ionized, plasmoid. Owing to plasma is considered as magnetic fluid in microwave, very big to the impedance influences of reaction chamber, the most logical Cross the coupling to reaction chamber impedance and be typically difficulty with the impedance matching to two kinds of different conditions.

Utility model content

This utility model has designed and developed a kind of secondary coupled reaction cavity configuration, in course of reaction first Microwave energy is coupled in the Cylindrical Resonators that annular reaction cavity wall is constituted, and passes through annular reaction the most again The perforate of cavity wall is coupled to microwave energy in reaction chamber, provides energy for reforming plasma reaction chamber, Make that coupling efficiency is higher, microwave energy is more evenly distributed in reaction chamber.

Another purpose of the present utility model is slotted at annular reaction cavity wall, by controlling reaction chamber Wall CURRENT DISTRIBUTION, controls microwave mode in reaction chamber, thus so that reaction chamber is to reaction chamber internal resistance resistance Change and there is higher tolerance, improve reaction efficiency.

The technical scheme that this utility model provides is:

A kind of secondary coupled microwave plasma reformer, including:

Cavity, it is circular cylindrical cavity；

Disc waveguide, it is looped around described chamber central position, in being divided into by described cavity and being positioned at The cylinder resonator of heart position and outside annular reaction chamber, described disc waveguide is provided with multiple circumference The coupling window that direction is distributed symmetrically and evenly；

Microwave plasma reaction tube, it is arranged on center, described annular reaction chamber, described microwave etc. from It is connected with air mixture in daughter reaction tube；

Coupling device, it is quarter wave resonator coupling device, is arranged on described intra resonant cavity；

Ignitor, it includes two one metal wires, connects high voltage power supply, be arranged on described microwave plasma At the air inlet port of gas reaction tube, needed for producing formation plasma in plasma reaction pipe Initial charge；

Wherein, microwave energy can be entered in described cylinder resonator by described coupling device, then passes through Described coupling window is coupled into described annular reaction intracavity.

Preferably, described coupling window is rectangle, circular or oval.

Preferably, described disc waveguide is provided with multiple little slit, for annular reaction intracavity Wall electric current cuts.

Preferably, side, described annular reaction chamber is provided with air inlet, and described air inlet couples with described One in window is oppositely arranged, and described microwave plasma reaction tube connects with described air inlet.

Preferably, described microwave plasma reaction tube is quartz ampoule, earthenware or fiber pipe.

Preferably, described microwave plasma reaction tube is circular multi-circle spiral flow shape pipeline or cross section For oval individual pen annulus line.

Preferably, described disc waveguide sectional area is rectangle.

Preferably, described cavity material is metal less to microwave absorption.

A kind of secondary coupled microwave plasma reformer, including:

Cavity, it is circular cylindrical cavity；

Disc waveguide, it is looped around described chamber central position, in being divided into by described cavity and being positioned at The cylinder resonator of heart position and outside annular reaction chamber, described disc waveguide is provided with multiple circumference The coupling window that direction is distributed symmetrically and evenly；

Microwave plasma reaction tube, it is arranged on center, described annular reaction chamber, described microwave etc. from It is connected with air mixture in daughter reaction tube；

Coupling device, it is probe coupling device, is arranged on described intra resonant cavity；

Ignitor, it includes two one metal wires, connects high voltage power supply, at plasma reaction pipe The interior initial charge produced needed for formation plasma；

Wherein, microwave energy can be entered in described cylinder resonator by described coupling device, then passes through Described coupling window is coupled into described annular reaction intracavity.

Preferably, described probe coupling device uses discoid or solid bell mouth shape probe.

Beneficial effect described in the utility model

1, the secondary coupled microwave plasma reformer that this utility model provides and traditional approach are by visiting Pin coupling is directly coupled to reaction chamber microwave energy, and to compare coupling efficiency higher, and this utility model is reformed dress Put and first microwave energy is coupled to cylinder resonator, then by multiple coupling windows of cylinder resonator micro- Wave energy is coupled to reaction chamber, is equivalent to multiport and couples simultaneously, and microwave energy is distributed more in reaction chamber Uniformly.

2, reaction chamber internal impedance is changed by the secondary coupling scheme that this utility model provides compared to direct-coupling Tolerance is higher, has taken into full account the impedance variation after reaction chamber is before ignition, and Multi-port Coupling makes instead Even if answering chamber impedance numerous imbalances, also much more as far as possible microwave energy and can be coupled to reaction chamber uniformly.

3, the secondary coupled microwave plasma reformer that this utility model provides, introduces the cutting of wall electric current Control the microwave mode distribution in reaction chamber, not only can effectively suppress under chamber plasma body state Parasitic mode interference, when reaction chamber internal impedance drastically changes, as igniting before and after, it is also possible to control reaction chamber Interior microwave mode change, makes reaction chamber microwave mode more stable, and smooth ignition forms plasma.

4, the secondary coupled microwave plasma reformer that this utility model provides, is either used for coupling The big coupling window of microwave energy still cuts the little slit of wall electric current and is at inside hollow closed cavity, no Microwave radiation can be caused.

5, this utility model provide secondary coupled microwave plasma reformer compact conformation volume little, And it is safe and efficient.

Accompanying drawing explanation

Fig. 1 is secondary coupled microwave plasma reformer top view described in the utility model.

Fig. 2 is secondary coupled microwave plasma reformer side view described in the utility model.

Fig. 3 is that the secondary coupled microwave plasma that this utility model utilizes electromagnetic simulation software to build is reformed Device threedimensional model.

Fig. 4 is spiral type multi-turn plasma reaction pipe described in the utility model.

Fig. 5 be cross section described in the utility model be oval plasma reaction pipe.

Fig. 6 is the secondary coupled microwave plasma weight taking discoid probe to couple described in the utility model Engagement positions.

Fig. 7 is the secondary coupling microwaves plasma taking bell mouth shape probe to couple described in the utility model Body weight engagement positions.

The some microwave mode figures being likely to occur in Fig. 8 reaction chamber described in the utility model.

Detailed description of the invention

Below in conjunction with the accompanying drawings this utility model is described in further detail, to make those skilled in the art Can implement according to this with reference to description word.

As it is shown in figure 1, the secondary coupled microwave plasma reformer that this utility model provides, including: Microwave plasm reaction cavity 1001, cylinder resonator 1002, plasma reaction pipe 1003, coupling The parts such as device 1004 and ignitor 1005.

Wherein, the cavity of reformer is the hollow cylinder cavity vertically placed, in chamber central position, Being surrounded with the disc waveguide 1007 that cross section is rectangle, 1007 hollow cylinder cavitys of disc waveguide divide For two parts, wherein disc waveguide 1007 and circular cylindrical cavity outer wall 1006 form microwave plasma ring Shaped reaction chamber 1001, disc waveguide 1007 constitute again in cylindrical cavity center one less Cylinder resonator 1002, preferred as one, the cavity of reformer selects less to microwave absorption Metal material makes.

As it is shown on figure 3, microwave plasm reaction cavity 1001 is annular housing, it is annular reaction chamber, Annular housing both sides are by flange seal, it is desirable to an annular housing at least side flange 1006-3 is dismountable, So can be convenient for changing plasma reaction pipe 1003, the side of having on annular reaction cavity outer wall 1006 Just gas piping turnover air outlet 1006-1 and air inlet port 1006-2, plasma reaction pipe 1003 It is placed on microwave plasm reaction cavity 1001 center, advantage of this is that and both can make plasma Precursor reactant pipe 1003 is positioned at the bigger position of reaction chamber field intensity, can ensure that again plasma reaction pipe 1003 Length, improve reforming plasma reaction efficiency,

As shown in Figure 4,5, plasma reaction pipe 1003 by high temperature resistant wave-permeable material make (as quartz, The materials such as pottery), plasma reaction pipe 1003 can be made cross section is circular multi-circle spiral flow shape Pipeline 1003-1, it is also possible to it is oval individual pen annulus line 1003-2 that reaction pipeline is made cross section, Under conditions of processing technique allows, prioritizing selection cross section is oval individual pen annulus line, so may be used To be effectively improved the reacting gas volume in reaction pipeline, thus improve reaction yield.

As it is shown on figure 3, cylinder resonator 1002 is positioned at the center of reformer, cylinder resonator The outer wall of 1002 is made up of disc waveguide 1007.Disc waveguide 1007 have some at circumferencial direction The coupling window 1007-1 being distributed symmetrically and evenly, coupling window is usually rectangular slot, it is also possible to be circular, ellipse The symmetrical structures such as circle, can realize preferable coupling effect.The quantity of coupling window 1007-1 and position are by micro- Microwave mode distribution in ripple plasm reaction cavity 1001 determines.If selecting rectangle coupling window, coupling The half of the generally annular duct height of height of window 1007-1, width is that the three of disc waveguide cross section arrives Five times, concrete size can be estimated by electromagnetic principles and by professional software simulation optimization.

Simultaneously, it is contemplated that the gas in plasma reaction pipe 1003 before ignition with igniting after one little The section time is not in plasmoid, microwave plasm reaction cavity 1001 during this period of time impedance Change is very big, and microwave plasm reaction cavity 1001 is difficult to meet the impedance matching of two states, resistance simultaneously The change of reaction chamber microwave mode can be caused again, if at plasma reaction pipe during resistance Hua Tai Datong District Before forming plasma completely in 1003, microwave mode change in microwave plasm reaction cavity 1001 Very big, reaction chamber internal electric field is unstable, and major part microwave energy is reflected back in coupling port, Plasma may be hardly formed in microwave plasm reaction cavity 1001.And microwave plasm reaction cavity In 1001, microwave mode distribution and reactor wall CURRENT DISTRIBUTION are closely bound up, therefore can be at microwave plasma On precursor reactant chamber 1001 inwall i.e. disc waveguide 1007, then have the little slit of some narrower in width 1007-2, cuts reaction chamber inwall wall electric current, and the position of little slit 1007-2 should be by plasma Under body state, the wall CURRENT DISTRIBUTION of reaction chamber determines.In order to prevent little slit 1007-2 in microwave electric field effect Lower electric discharge, it is also possible at little slit 1007-2 position fill insulant.Wall electric current cuts little slit 1007-2 Introducing, not only can control the microwave mode of reaction chamber when impedance is lacked of proper care, and at microwave plasma When precursor reactant chamber 1001 impedance matching is good, it is also possible to the parasitic mode interference in suppression reaction chamber.

Coupling device 1004, the effect of coupling device is that the microwave energy in transmission line is coupled to microwave etc. In gas ions reaction chamber 1001, reduce microwave energy reflection at coupling port as far as possible.Work as plasma In precursor reactant pipe 1003, gaseous state changes, during microwave plasm reaction cavity 1001 impedance imbalance, One good coupling device can make up the impact that reaction chamber is brought by impedance variation to a great extent, Microwave energy as much as possible is coupled to reaction chamber.The coupling device 1004 of cylinder resonator 1002 is permissible Be probe coupling, the shape of probe can be discoid can also be solid bell mouth shape, respectively as Fig. 6, Shown in Fig. 7.In order to preferably microwave energy is coupled to cylinder resonator 1002, it would however also be possible to employ 1/4 Wavelength resonant cavity coupling device, as shown in Figure 2.Microwave energy in transmission line 1004-3 is through impedance matching Device 1004-2 is delivered in 1/4 wavelength resonant cavity 1004-1, then through 1/4 wavelength resonant cavity 1004-1 coupling Close hole and be coupled in cylinder resonator 1002, when cylinder resonator 1002 impedance Incomplete matching, micro- Wave energy is reflected into 1/4 wavelength resonant cavity 1004-1 via coupling aperture, is again introduced into cylinder humorous after resonance Shake chamber 1002.Can be microwave energy as much as possible as coupling device with 1/4 wavelength resonant cavity 1004-1 Amount is coupled to cylinder resonator 1002, and this utility model preferably 1/4 wavelength resonant cavity is as coupling device.

Ignitor 1005, is typically made up of two one metal wires, is powered by high voltage power supply, and its effect is The initial charge formed needed for plasma is produced in plasma reaction pipe 1003.Ignitor 1005 Being typically placed in certain position in plasma reaction pipe 1003 air inlet port 1006-2, therefore this is also Require that plasma reaction pipe 1003 air inlet port is in the right opposite of certain coupling window 1007-1, do so Benefit be to can ensure that near ignitor 1005 that microwave field density 1008 is relatively big, utilize plasma Formation.

Implement as a example by the work process of secondary coupled microwave plasma reformer, make further It is bright,

The microwave that other microwave generating apparatus such as magnetron or Solid Source produce, via transmission line, coupling Device 1004, is coupled to microwave energy in cylinder resonator 1002, and microwave is at cylinder resonator 1002 Interior generation resonance, is then coupled to microwave energy via the coupling window 1007-1 in disc waveguide 1007 In microwave plasm reaction cavity 1001.When in plasma reaction pipe 1003, gas is in plasma During state, reaction chamber internal resistance hole coupling is good, is operated in predetermined microwave mode, reforms in reaction chamber Reaction, reforming reaction absorbs a large amount of microwave energys.This state coupling device 1004 is coupled to cylinder resonance The microwave energy in chamber 1002 is all coupled to via the coupling window 1007-1 major part in disc waveguide 1007 Reactive absorption, the microwave pole of coupling window 1007-1 reflection it is reformed in microwave plasm reaction cavity 1001 Few, therefore in cylinder resonator 1002, microwave is not operate at mode of resonance, and resonance value is the least in other words.Circle Post resonator cavity 1002 role is via the uniform coupling of multiple coupling port 1007-1 microwave energy Close in microwave plasm reaction cavity 1001, provide energy for reforming reaction.And work as microwave plasma Reformer is operated in ignition mode, is also formed without plasma shape in plasma reaction pipe 1003 State, reaction chamber internal impedance do not mates, and coupling window 1007-1 is coupled to microwave plasm reaction cavity 1001 Interior microwave energy major part is reflected again, and coupling device 1004 is coupled to cylinder resonator 1002 Microwave major part all rested in cylinder resonator 1002, cylinder resonator 1002 resonance value is relatively big, Intracavity electric field intensity is strengthened, microwave energy be equivalent to amplify in cylinder resonator 1002 after coupling again Close in reaction chamber 1001, it is achieved as much as possible microwave energy has been coupled to reaction chamber.

As shown in Figure 8, in another embodiment, microwave plasm reaction cavity 1001 is in the design process Need to meet two kinds of duties simultaneously, plasma igniting can be smoothly completed in fired state, waiting Form plasma in gas ions reaction tube 1003, ionization reaction gas can be continued again under plasmoid Body, provides energy for reformation reaction chamber 1001.In order to meet two different duties, herein simultaneously The solution be given is: allow reaction chamber be operated in different respectively in fired state and plasmoid Microwave mode, the some ideographs being likely to occur in reaction chamber, be likely to occur annular reaction intracavity is micro- Wave mode comprehensively analyzes discovery, the difference correlation of the internal-and external diameter of the microwave under TM pattern and reaction chamber, and And microwave electric field intensity is uniformly distributed along reaction chamber circumference under TM01 pattern, beneficially microwave plasma Reaction chamber 1001 smooth ignition, therefore under fired state, microwave prioritizing selection is operated in TM01 pattern, when Microwave frequency be the difference of the reaction chamber internal-and external diameter being operated in TM01 pattern during 2.45GHZ be 62mm.? In requiring reaction chamber under plasmoid, microwave field density distribution is the most more uniform, therefore can select Under gas ions pattern, microwave operational is at TE31 pattern or TE41 pattern (TE41 ideograph and TE31 Ideograph is similar to, and TE31 pattern has 6 each crests in circumference, and TE41 pattern has 8 crests in circumference). Microwave plasm reaction cavity 1001 center-line perimeter should be the integral multiple of waveguide wavelength, and calculating can obtain Going out under 2.45GHZ microwave condition reaction chamber internal diameter under TE31 mode of operation should be for 43.8mm.Need to refer to The reaction chamber internal diameter size gone out is the result of calculation under non-plasma state, and its concrete numerical value should be Software optimization correction is analyzed by Electromagnetic Simulation under plasmoid.

Microwave plasm reaction cavity 1001 microwave operational pattern may determine that coupling window after determining immediately The quantity of 1007-1 and position.The particular number of coupling device should be with microwave plasm reaction cavity 1001 Interior standing wave number is corresponding, and coupling window should be near reaction chamber associative mode field intensity maximum position simultaneously, The quantity of coupling window can be less than reaction chamber standing internal wave number, but coupling window should be symmetrical in reaction chamber inner circumferential Distribution.

A kind of microwave plasm reaction cavity field intensity map being operated under TE31 pattern, works as coupling window When quantity is three, microwave energy can more uniform be coupled in reaction chamber.

When microwave plasma reformer selects 1/4 wavelength resonant cavity as coupling device 1004, by It is spherical wave in resonator cavity outgoing wave, in order to microwave preferably reflects bottom cylinder resonator 1002, circle Post resonator cavity 1002 flange in the bottom not should be designed so that plane, it should is spherical crown shape, the home position of spherical crown It is in resonator cavity perforation hole position.

Secondary coupled microwave plasma reformer described in the utility model is many by cylinder resonator Individual coupling port is coupled to reforming reaction intracavity microwave energy and not only can ensure that at reforming plasma shape State microwave energy is coupled in reaction chamber uniformly, but also considers the igniting shape in impedance imbalance simultaneously State, by appropriate design reaction chamber size, allows reaction chamber meet the job requirement of two kinds of different conditions, knot Close Multi-port Coupling and the cutting of wall electric current, it is ensured that reformer smooth ignition.

Although embodiment of the present utility model is disclosed as above, but it is not restricted to description and reality Executing listed in mode utilization, it can be applied to various applicable field of the present utility model completely, for For those skilled in the art, it is easily achieved other amendment, therefore without departing substantially from claim And under the general concept that limited of equivalency range, this utility model is not limited to specific details and shows here The legend gone out and describe.

Claims (10)

1. a secondary coupled microwave plasma reformer, it is characterised in that including:

Cavity, it is circular cylindrical cavity；

Disc waveguide, it is looped around described chamber central position, in being divided into by described cavity and being positioned at The cylinder resonator of heart position and outside annular reaction chamber, described disc waveguide is provided with multiple circumference The coupling window that direction is distributed symmetrically and evenly；

Microwave plasma reaction tube, it is arranged on center, described annular reaction chamber, described microwave etc. from It is connected with air mixture in daughter reaction tube；

Coupling device, it is quarter wave resonator coupling device, is arranged on described intra resonant cavity；

Ignitor, it includes two one metal wires, connects high voltage power supply, be arranged on described microwave plasma At the air inlet port of gas reaction tube, needed for producing formation plasma in plasma reaction pipe Initial charge；

Wherein, microwave energy can be entered in described cylinder resonator by described coupling device, then passes through Described coupling window is coupled into described annular reaction intracavity.

Secondary coupled microwave plasma reformer the most according to claim 1, its feature exists It is rectangle, circular or oval in, described coupling window.

Secondary coupled microwave plasma reformer the most according to claim 2, its feature exists In, described disc waveguide is provided with multiple little slit, for the wall electric current of annular reaction intracavity is carried out Cutting.

Secondary coupled microwave plasma reformer the most according to claim 3, it is characterised in that Side, described annular reaction chamber is provided with air inlet, and described air inlet is relative with in described coupling window Arranging, described microwave plasma reaction tube connects with described air inlet.

Secondary coupled microwave plasma reformer the most according to claim 1, it is characterised in that Described microwave plasma reaction tube is quartz ampoule, earthenware or fiber pipe.

Secondary coupled microwave plasma reformer the most according to claim 5, it is characterised in that Described microwave plasma reaction tube is circular multi-circle spiral flow shape pipeline or cross section is oval individual pen Annulus line.

Secondary coupled microwave plasma reformer the most according to claim 1, it is characterised in that Described disc waveguide sectional area is rectangle.

Secondary coupled microwave plasma reformer the most according to claim 1, it is characterised in that Described cavity material is metal less to microwave absorption.

9. a secondary coupled microwave plasma reformer, it is characterised in that including:

Cavity, it is circular cylindrical cavity；

Disc waveguide, it is looped around described chamber central position, in being divided into by described cavity and being positioned at The cylinder resonator of heart position and outside annular reaction chamber, described disc waveguide is provided with multiple circumference The coupling window that direction is distributed symmetrically and evenly；

Microwave plasma reaction tube, it is arranged on center, described annular reaction chamber, described microwave etc. from It is connected with air mixture in daughter reaction tube；

Coupling device, it is probe coupling device, is arranged on described intra resonant cavity；

Ignitor, it includes two one metal wires, connects high voltage power supply, at plasma reaction pipe The interior initial charge produced needed for formation plasma；

Wherein, microwave energy can be entered in described cylinder resonator by described coupling device, then passes through Described coupling window is coupled into described annular reaction intracavity.

Secondary coupled microwave plasma reformer the most according to claim 9, its feature exists In, described probe coupling device uses discoid or solid bell mouth shape probe.