CN113144899B

CN113144899B - Low-temperature plasma catalysis experimental device for purifying tail gas

Info

Publication number: CN113144899B
Application number: CN202110422542.8A
Authority: CN
Inventors: 郭大江; 王江林; 林顺洪; 杨宇; 华炜俊; 周翼; 颜子力
Original assignee: Chongqing University of Science and Technology
Current assignee: Chongqing University of Science and Technology
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2022-08-30
Anticipated expiration: 2041-04-20
Also published as: CN113144899A

Abstract

The invention provides a low-temperature plasma catalysis experimental device for purifying tail gas, which comprises a reaction tube, an inner electrode and an outer electrode, wherein the inner electrode is arranged in the reaction tube, the outer electrode is sleeved outside the reaction tube, the top of the reaction tube is connected with an air inlet tube, and the bottom of the reaction tube is connected with an air outlet tube. The tube body of the reaction tube is provided with discharge tubes, the four discharge tubes are arranged in an annular array along the axis of the reaction tube, and the discharge tubes are provided with electromagnetic valves; the experimental device further comprises a shell, an upper seat body, a feeding door, a reset mechanism and four feeding mechanisms. Through the design of throwing the material mechanism, can pack fast and change the catalyst, promoted the convenience of experiment operation. Meanwhile, the device can simulate the influence of different catalyst particle sizes on the waste gas purification efficiency, and the application range of the experimental device is greatly widened.

Description

Low-temperature plasma catalysis experimental device for purifying tail gas

Technical Field

The invention relates to the technical field of waste gas purification, in particular to a low-temperature plasma catalysis experimental device for purifying tail gas.

Background

With the rapid development of economy, the number of automobiles is rapidly increased, so that the problem of exhaust pollution is increasingly serious. Dielectric Barrier Discharge (DBD) is a reliable method for generating low-temperature (non-equilibrium state) plasma under atmospheric pressure, and through large-area uniform Discharge, organic molecules, water molecules and oxygen molecules can be sufficiently ionized, so as to excite more active species, and the method has the advantages of higher safety, longer electrode life, higher average electron energy and the like.

The purification efficiency of the pure low-temperature plasma for treating the automobile exhaust is only about 50%, so that the low-temperature plasma for treating the exhaust needs the assistance of a catalyst, the low-temperature plasma and the catalyst have different synergistic modes, and the proposed effects are different, wherein the influence relationship of different particle sizes of the catalyst on the NO purification efficiency needs to be emphatically compared with the experimental results. At present, the catalysts are manually added during filling and replacing reaction tubes, the filling and replacing speed is low, and the influence of the catalysts with various particle sizes on the NO purification efficiency is not easy to simulate.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a low-temperature plasma catalysis experimental device for purifying tail gas, so as to improve the convenience of the experiment and facilitate the simulation of the influence of different catalyst particle sizes on the waste gas purification efficiency.

In order to achieve the purpose, the invention provides a low-temperature plasma catalysis experimental device for purifying tail gas, which comprises reaction tubes, wherein the top and the bottom of each reaction tube are respectively communicated with an air inlet tube and an air outlet tube;

still include the casing, it has a plurality of louvres to run through on the conch wall of casing, the reaction tube is in along vertical setting in the casing, still be provided with in the casing:

the upper seat body is arranged on the top wall of the inner cavity of the shell and is sealed and sleeved at the top end of the reaction tube, and four feed inlets communicated with the reaction tube are arranged on the outer wall of the upper seat body;

the throwing door can slide along the vertical direction and is used for sealing the feeding hole;

the resetting mechanism is used for resetting the throwing door after the throwing door is pushed open; and

four feeding mechanisms arranged in the shell in an annular array along the axis of the reaction tube, the feeding mechanisms comprising:

the opening of the collecting frame is arranged upwards, and a material leakage port is arranged on one side of the collecting frame close to the reaction tube;

the sliding door mechanism is used for closing or opening the material leakage port; and

the lifting mechanism is used for driving the collection frame to lift;

when the lifting mechanism drives the collecting frame to ascend, the catalyst in the collecting frame can be put into the feed port; when the lifting mechanism drives the collecting frame to descend, the collecting frame can collect the catalyst poured out of the discharging pipe.

Preferably, the upper seat body is of a rectangular columnar structure, and the throwing door is attached to the outer wall of the upper seat body in a sliding manner;

the sliding door mechanism comprises a sealing plate and an air cylinder, the sealing plate is vertically matched on the outer wall of the collecting frame on one side close to the reaction tube in a sliding mode, and the air cylinder is arranged on the outer side of the collecting frame;

the collecting frame is close to be provided with the sand grip on the outer wall of reaction tube one side, the sand grip is located the top of shrouding, the sand grip the shrouding with throw in the thickness of door the same.

Preferably, the collecting device further comprises an inclined plate arranged in the collecting frame, the lower end of the inclined plate is connected with the bottom end of the material leakage port, and a plurality of air holes are formed in the inclined plate;

the collecting frame is further provided with a blowing mechanism, the blowing mechanism comprises a fan and an air pipe, the fan is arranged at the bottom of the collecting frame, one end of the air pipe is connected with the fan, the other end of the air pipe extends into the collecting frame and is positioned in an included angle space formed by the inclined plate and the collecting frame, and an air outlet of the air pipe is opposite to the material leakage port;

the novel collecting device is characterized by further comprising four cover plates, wherein the cover plates are arranged at the top of the inner cavity of the shell and located right above the collecting frame, sealing gaskets are arranged on the bottom surfaces of the cover plates, when the lifting mechanism drives the collecting frame to ascend and push the throwing door open, and the cover plates are used for sealing an opening of the collecting frame.

Preferably, the lifting mechanism includes:

a motor disposed at a top of the housing;

the screw rod is vertically and rotatably arranged in the shell and is connected with the motor;

the support is arranged on one side, away from the reaction tube, of the collecting frame, and the support is in threaded fit with the screw rod; and

the sliding seat is arranged at one end, far away from the support, of the collecting frame, and a first sliding groove in sliding fit with the sliding seat is vertically formed in the wall of the inner cavity of the shell.

Preferably, a second sliding groove is formed in the outer wall of the upper seat body, the second sliding groove is vertically arranged, and a sliding block in sliding fit with the second sliding groove is arranged on one side, facing the upper seat body, of the throwing door;

the reset mechanism comprises two guide rods, the two ends of each guide rod are respectively connected with the upper seat body and the inner cavity top wall of the shell, a connecting sleeve and a spring are sleeved on each guide rod in a penetrating mode, the connecting sleeves are connected to the tops of the throwing doors, and the two ends of each spring are respectively connected with the inner cavity top wall of the shell and the connecting sleeves.

Preferably, be provided with inner electrode and filter screen in the reaction tube, the top of inner electrode with go up the seat body coupling, the filter screen is the toper platform structure, the edge of filter screen with the discharging pipe links up, the confession has been seted up at the top of filter screen the through-hole that the inner electrode passed.

Preferably, a mixing cavity is arranged in the upper seat body, a plurality of air inlets communicated with the reaction tube penetrate through the cavity bottom of the mixing cavity, and the air inlet tube is communicated with the mixing cavity;

the gas-liquid separation device is characterized by further comprising a lower seat body, wherein the lower seat body is arranged on the bottom wall of the inner cavity of the shell and is hermetically sleeved at the bottom end of the reaction tube, and the gas outlet tube penetrates through the lower seat body and then is communicated with the reaction tube.

The invention has the beneficial effects that:

1. the invention discloses a low-temperature plasma catalysis experimental device for purifying tail gas, which is characterized in that a feeding mechanism is designed, a catalyst can be added into a collecting frame before an experiment, the collecting frame is driven to ascend through a lifting mechanism to open a feeding hole, so that the catalyst in the collecting frame is fed into a reaction tube through the feeding hole to fill a gap between an inner electrode and the inner wall of the reaction tube, high-energy active particles generated in the discharging process can quickly combine with the catalyst for reaction, and the utilization efficiency of the active particles and the removal efficiency of gas pollutants are improved. When the catalyst needs to be replaced, the catalyst particles in the reaction tube can flow out of the discharge tube and be collected by the collecting frame by opening the discharge tube, so that subsequent experimental operation is facilitated. Throw material mechanism through the design, packing that can be quick and change catalyst have promoted the convenience of experiment operation. This experimental apparatus is through filling the catalyst to the reaction tube, when improving exhaust purification efficiency, has also reduced energy consumption and cost.

2. Through four independent feeding mechanisms of design in the casing, every collecting frame of feeding in the mechanism can splendid attire different particle size's catalyst, like this, just can simulate different catalyst particle size under the condition that uses a device and to exhaust purification efficiency's influence effect, improved this experimental apparatus's application scope greatly.

Drawings

In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings used in the detailed description or the prior art description will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

Fig. 1 is a schematic structural diagram of a low-temperature plasma catalysis experimental apparatus for purifying exhaust gas according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a feed mechanism preparing to feed catalyst into a feed port;

FIG. 3 is an enlarged view of a portion of the convex strip about to push the dispensing door upward;

fig. 4 is a partially enlarged view of the state of fig. 2.

Reference numerals:

1-reaction tube, 11-inlet tube, 12-outlet tube, 13-outlet tube, 2-shell, 21-first chute, 3-upper seat, 31-inlet opening, 32-feeding door, 33-mixing chamber, 34-inlet opening, 4-reset mechanism, 41-guide rod, 42-connecting sleeve, 43-spring, 5-feeding mechanism, 51-collecting frame, 511-leakage opening, 52-closing plate, 53-cylinder, 54-raised strip, 55-inclined plate, 551-air hole, 56-motor, 57-screw rod, 58-support, 59-slide seat, 6-blowing mechanism, 61-blower, 62-air tube, 7-cover plate, 81-inner electrode, 82-outer electrode, 9-filter screen, 10-lower base.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.

In the description of the present application, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, but are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the invention.

Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

As shown in fig. 1 to 4, in an embodiment of the present invention, a low temperature plasma catalysis experiment apparatus for purifying exhaust gas is provided, which includes a reaction tube 1, an inner electrode 81 and an outer electrode 82, the inner electrode 81 is disposed in the reaction tube 1, the outer electrode 82 is sleeved outside the reaction tube 1, the top of the reaction tube 1 is connected to an air inlet tube 11, and the bottom of the reaction tube 1 is connected to an air outlet tube 12.

Discharge pipes 13 are arranged on the body of the reaction pipe 1, the four discharge pipes 13 are arranged in an annular array along the axis of the reaction pipe 1, and electromagnetic valves are arranged on the discharge pipes 13; the experimental device further comprises a shell 2, an upper seat body 3, a feeding door 32, a reset mechanism 4 and four feeding mechanisms 5. Wherein, a plurality of heat dissipation holes are penetrated through the wall of the shell 2 so as to dissipate the heat of the reaction tube 1 after discharging.

The upper seat body 3 is arranged at the top of the inner cavity of the shell 2 and is sealed and sleeved at the top end of the reaction tube 1, four feed inlets 31 communicated with the reaction tube 1 are arranged on the outer wall of the upper seat body 3, and catalyst particles are filled into the reaction tube 1 through the feed inlets 31. The throwing door 32 can slide along the vertical direction, the throwing door 32 is used for sealing the feed port 31 so as to avoid gas in the reaction tube 1 from escaping, and the resetting mechanism 4 is used for resetting the throwing door 32 after the throwing door 32 is pushed open so as to seal the feed port 31 again.

The four feeding mechanisms 5 are arranged in the shell 2 in an annular array along the axis of the reaction tube 1, wherein the feeding mechanisms 5 comprise a collecting frame 51, a sliding door mechanism and a lifting mechanism, the opening of the collecting frame 51 faces upwards, the collecting frame 51 is used for collecting and containing the catalyst, a material leakage port 511 is arranged on one side of the collecting frame 51 close to the reaction tube 1, the lifting mechanism is used for driving the collecting frame 51 to lift, and when the lifting mechanism drives the collecting frame 51 to lift, the catalyst in the collecting frame 51 can be fed into the material leakage port 31; when the elevating mechanism drives the collecting frame 51 to descend, the collecting frame 51 can collect the catalyst poured out from the discharging pipe 13.

The low temperature plasma catalysis experimental apparatus for purifying tail gas of this embodiment, it throws material mechanism 5 through the design, can add the catalyst in collecting frame 51 before the experiment, it rises to open feed inlet 31 to collect frame 51 through the elevating system drive, thereby throw into the reaction tube 1 through feed inlet 31 with the catalyst in collecting frame 51, make it fill up the clearance between inner electrode 81 and the reaction tube 1 inner wall, high energy active particle that produces in the discharge process can combine reaction with the catalyst fast, thereby improve active particle's utilization efficiency and the desorption efficiency to gas pollutants, and simultaneously, the plasma can degrade material such as aerosol on the catalyst, make the catalyst be difficult to the deactivation.

When the catalyst needs to be replaced, the catalyst particles in the reaction tube 1 can flow out of the discharge pipe 13 and be collected by the collection frame 51 by opening the discharge pipe 13, thereby facilitating the subsequent experiment operation. Throw material mechanism through the design, packing that can be quick and change catalyst have promoted the convenience of experiment operation. This experimental apparatus is through filling the catalyst to the reaction tube, when improving exhaust purification efficiency, has also reduced energy consumption and cost.

In addition, four independent feeding mechanisms 5 are designed in the shell 2, and the collecting frame 51 in each feeding mechanism 5 can contain catalysts with different particle sizes, so that the influence of different catalyst particle sizes on the waste gas purification efficiency can be simulated under the condition of using one device, and the application range of the experimental device is greatly widened.

In one embodiment, the upper base 3 is a rectangular column structure, and the throwing door 32 is slidably attached to the outer wall of the upper base 3; the sliding door mechanism comprises a sealing plate 52 and an air cylinder 53, the sealing plate 52 is vertically matched on the outer wall of the collecting frame 51 close to one side of the reaction tube 1 in a sliding manner, and the air cylinder 53 is arranged on the outer side of the collecting frame 51; the outer wall of the collecting frame 51 close to one side of the reaction tube 1 is provided with a convex strip 54, the convex strip 54 is positioned above the sealing plate 52, the thicknesses of the convex strip 54, the sealing plate 52 and the throwing door 32 are the same, and the plate surfaces of the sealing plate 52 and the throwing door 32 are vertically overlapped. When the elevator mechanism drives the collection frame 51 to ascend, the convex strip 54 pushes the throwing door 32 upward, so that the throwing door moves upward, and the feed port 31 is opened. Then, the cylinder 53 moves downward with the closing plate 52 to gradually open the material discharge opening 511, so that the catalyst particles in the collecting frame 51 can enter the reaction tube 1 through the material inlet 31 until the reaction tube 1 is filled.

In one embodiment, the material collecting device further comprises an inclined plate 55 arranged in the collecting frame 51, the lower end of the inclined plate 55 is connected with the bottom end of the material leaking port 511, and a plurality of air holes 551 are formed in the inclined plate 55; the collecting frame 51 is further provided with a blowing mechanism 6, the blowing mechanism 6 comprises a fan 61 and an air pipe 62, the fan 61 is arranged at the bottom of the collecting frame 51, one end of the air pipe 62 is connected with the fan 61, the other end of the air pipe 62 extends into the collecting frame 51 and is positioned in an included angle space formed by the inclined plate 55 and the collecting frame 51, and an air outlet of the air pipe 62 is over against the material leakage port 511; still include four apron 7, apron 7 sets up at the inner chamber top of casing 2, and apron 7 is located and collects frame 51 directly over, and the bottom surface of apron 7 is provided with sealed the pad, and after elevating system drive collection frame 51 rose and pushed open and put door 32, the apron was used for sealing the uncovered of collecting frame 51. By designing the inclined plate 55 and the blowing mechanism 6 in the collecting frame 51, the inclined plate 55 is designed to facilitate the flow of the catalyst particles to the material leakage opening 511, and after the fan 61 is started, the air from the air pipe 62 is blown out from the air hole 551 on the inclined plate 55, so that the flow speed of the catalyst particles can be increased, and the catalyst particles can rapidly flow from the collecting frame 51 to the material inlet 31. Meanwhile, the design of the cover plate 7 can ensure that the collecting frame 51 only has an outlet of the material leakage opening 511, so that the function and the effect of the material blowing mechanism 6 can be more obvious.

In one embodiment, the lift mechanism includes a motor 56, a lead screw 57, a support 58, and a slide 59. The motor 56 is installed on the top of the housing 2, and the screw 57 is vertically and rotatably disposed in the housing 2 and connected to the motor 56. The support 58 is connected in the one side that collects frame 51 and deviates from reaction tube 1, and support 58 screw-thread fit is on lead screw 57, and slide 59 sets up the one end of collecting frame 51 far away at support 58, along vertical offered on the inner chamber wall of casing 2 with slide 59 sliding fit's first spout 21. Since the sliding seat 59 is confined in the first sliding slot 21, when the motor 56 drives the screw 57 to rotate, the support 58 can only move along the length direction of the screw 57, so as to drive the collecting frame 51 to move up and down.

In one embodiment, a second sliding groove is arranged on the outer wall of the upper seat body 3, the second sliding groove is arranged vertically, and a sliding block which is in sliding fit with the second sliding groove is arranged on one side, facing the upper seat body 3, of the throwing door 32; the reset mechanism 4 comprises two guide rods 41, two ends of each guide rod 41 are respectively connected with the upper wall of the inner cavity of the upper base body 3 and the top wall of the inner cavity of the shell 2, a connecting sleeve 42 and a spring 43 are sleeved on each guide rod 41 in a penetrating manner, the connecting sleeve 42 is connected with the top of the throwing door 32, and two ends of the spring 43 are respectively connected with the upper wall of the inner cavity of the shell 2 and the connecting sleeve 42. When the lifting mechanism drives the collecting frame 51 to rise, the convex strip 54 pushes the throwing door 32 upwards to move upwards along the second sliding chute, and simultaneously drives the connecting sleeve 42 to move upwards along the guide rod 41 and compress the spring 43. When the collecting frame 51 is driven by the lifting mechanism to descend, the spring 43 can rapidly push the connecting sleeve 42, so that the connecting sleeve 42 and the throwing door 32 are reset, the feed port 31 is shielded, and gas is prevented from escaping from the feed port 31 to influence experimental data.

In one embodiment, an inner electrode 81 and a filter screen 9 are disposed in the reaction tube 1, the top end of the inner electrode 81 is connected to the upper base 3, the filter screen 9 is in a conical table structure, the edge of the filter screen 9 is connected to the discharge tube 13, and a through hole for the inner electrode 81 to pass through is formed in the top of the filter screen 9. By designing the screen 9 in a conical-frustum structure, accumulation of catalyst particles to the bottom of the reaction tube 1 is avoided, and at the same time, the inclined outer wall of the screen 9 can contribute to the flow of the catalyst. After the discharge is finished, the purified gas can also pass through the filter screen 9 and is discharged from the gas outlet pipe 12.

In one embodiment, a mixing chamber 33 is arranged in the upper seat body 3, a plurality of air inlets 34 communicated with the reaction tube 1 penetrate through the bottom of the mixing chamber 33, and the air inlet pipe 11 is communicated with the mixing chamber 33; the device also comprises a lower seat body, the lower seat body is arranged on the bottom wall of the inner cavity of the shell 2 and is arranged at the bottom end of the reaction tube 1 in a sealing way, and the air outlet tube 12 penetrates through the lower seat body and then is communicated with the reaction tube 1. The structural design of the mixing chamber 33 can play a role in buffering gas mixing, so that the gas is uniformly mixed and then enters the reaction tube 1, and the accuracy of the experiment is further improved.

In the description of the present invention, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.

Claims

1. The utility model provides a low temperature plasma catalysis experimental apparatus for purifying tail gas, includes the reaction tube, the top and the bottom of reaction tube intercommunication respectively have intake pipe and outlet duct, its characterized in that: the reactor comprises a reaction tube, wherein the tube body of the reaction tube is provided with four discharge tubes, the four discharge tubes are arranged in an annular array along the axis of the reaction tube, and the discharge tubes are provided with electromagnetic valves for opening or closing the discharge tubes;

the upper seat body is arranged on the top wall of the inner cavity of the shell and is hermetically sleeved at the top end of the reaction tube, four feed inlets communicated with the reaction tube are formed in the outer wall of the upper seat body, the upper seat body is of a rectangular columnar structure, a second sliding groove is formed in the outer wall of the upper seat body, and the second sliding groove is vertically arranged;

the throwing door can slide along the vertical direction and is attached to the outer wall of the upper seat body, one side, facing the upper seat body, of the throwing door is provided with a sliding block in sliding fit with the second sliding groove, and the throwing door is used for sealing the feeding hole;

the resetting mechanism is used for resetting the throwing door after the throwing door is pushed open and comprises two guide rods, two ends of each guide rod are respectively connected with the upper base body and the top wall of the inner cavity of the shell, each guide rod is sleeved with a connecting sleeve and a spring in a penetrating manner, the connecting sleeves are connected to the top of the throwing door, and two ends of the spring are respectively connected with the top wall of the inner cavity of the shell and the connecting sleeves; and

four feeding mechanisms arranged in the shell in an annular array along the axis of the reaction tube, wherein the feeding mechanisms comprise:

the opening of the collecting frame is arranged upwards, and a material leakage port is formed in one side, close to the reaction tube, of the collecting frame;

the sliding door mechanism is used for closing or opening the material leakage port and comprises a sealing plate and an air cylinder, the sealing plate is vertically matched on the outer wall of the collecting frame close to one side of the reaction tube in a sliding mode, the air cylinder is arranged on the outer side of the collecting frame, a convex strip is arranged on the outer wall of the collecting frame close to one side of the reaction tube and located above the sealing plate, and the convex strip, the sealing plate and the feeding door are the same in thickness; and

the lifting mechanism is used for driving the collection frame to lift;

when the lifting mechanism drives the collecting frame to ascend, the catalyst in the collecting frame can be thrown into the feeding port; when the lifting mechanism drives the collecting frame to descend, the collecting frame can collect the catalyst poured out of the discharge pipe.

2. The assay device of claim 1, wherein: the collection frame is provided with a discharge hole, and the collection frame is provided with a collection frame;

3. The assay device of claim 1, wherein: the lifting mechanism comprises:

a motor disposed at a top of the housing;

the slide, its setting is in the support deviates from the one end of collecting the frame, along vertical seted up on the inner chamber wall of casing with slide sliding fit's first spout.

4. The assay device of claim 1, wherein: be provided with inner electrode and filter screen in the reaction tube, the top of inner electrode with go up the seat body coupling, the filter screen is the toper platform structure, the edge of filter screen with the discharging pipe links up, the confession has been seted up at the top of filter screen the through-hole that the inner electrode passed.

5. The assay device of claim 1, wherein: a mixing cavity is arranged in the upper seat body, a plurality of air inlets communicated with the reaction tube penetrate through the cavity bottom of the mixing cavity, and the air inlet tube is communicated with the mixing cavity;