KR20120049968A - Atmospheric pressure plasma gas scrubbing equipment - Google Patents

Abstract

PURPOSE: An apparatus for scrubbing an atmospheric pressure plasma gas is provided to improve the process efficiency of a process gas by maintaining a process gas to be 150 degrees or more as an indirect heat source of plasma. CONSTITUTION: A process gas inflow line(140) is connected to a bottom portion of an exterior wall(130b). The process gas inflow line lets a process gas to be processed flow from the outside. A process gas exhaust line(150) is connected to an upper end of the exterior wall. The process gas exhaust line discharges the process gas flowing in. An injection portion injects water into a waveguide(110).

Description

Atmospheric Pressure plasma gas scrubbing equipment

The present invention relates to an atmospheric pressure plasma gas scrubbing apparatus, and more particularly, to an atmospheric pressure plasma gas scrubbing apparatus capable of performing evaporation of water supplied by contacting a process gas and a heat source generated from a plasma torch before the plasma reactor.

When the temperature of a gaseous substance is continuously heated to raise its temperature, an aggregate of particles composed of an ion nucleus and free electrons is formed. Along with the three forms of matter, solid, liquid and gas, it is called the 'fourth state of matter' and this state of matter is called plasma. Various application devices using the plasma have been continuously developed and applied. One such plasma application is the treatment of waste gases which are essentially generated in semiconductors, chemical processes and the like.

One of the waste gas treatment methods according to the prior art is a combination of a plasma process and a water-cooled process. As an example, Korean Patent Laid-Open No. 10-2007-0066998 discloses a configuration including a gas treatment chamber in which a plasma process is performed, a nozzle for injecting water into the gas treatment chamber, a water tank generated from the gas treatment chamber, and the like. . However, the nozzle is provided with a nozzle for injecting water into the hot gas processing chamber, and induces direct evaporation of water in the hot gas processing chamber. In addition, since the evaporation process of water proceeds along with the reaction process, there is a problem that the reaction of the decomposed waste gas and water is delayed.

Furthermore, the waste gas generated from the semiconductor device and the like contains a large amount of powder components and sticky components, and thus easily adheres and aggregates over time, which causes clogging in the pipe. In order to prevent this problem, conventionally, a heating jacket was installed in the piping line, and the problem of agglomeration of powder or adhesive components with the temperature drop was solved by diluting the heated nitrogen (N2). There was a problem of ascension.

Accordingly, the problem to be solved by the present invention to solve the above problems is to provide an atmospheric pressure plasma scrubbing apparatus, which is economical and effective waste gas treatment compared to the prior art.

In order to solve the above problems, the present invention is a microwave generating unit; A waveguide to which microwaves generated from the microwave generator are applied; A dielectric tube connected to the waveguide and generating a plasma by microwaves applied in the waveguide to discharge the torch to the outside; A reactor connected to the bottom of the waveguide, the outer wall and the inner wall spaced at predetermined intervals, and the dielectric tube being provided inside the inner wall; A process gas inlet line connected to a lower end of the outer wall to receive a process gas to be treated from the outside; A process gas discharge line connected to an upper end of the outer wall to discharge the introduced process gas; And an injection part provided at an upper end of the waveguide, for injecting water into the waveguide, wherein the process gas discharge line is connected to the injection part, and after the water and the process gas are mixed in the injection part, It provides an atmospheric pressure plasma gas scrubbing apparatus, characterized in that it is introduced into the waveguide.

In one embodiment of the invention the reactor inner wall is made of one or more metals selected from the group consisting of stainless steel, aluminum and iron.

In one embodiment of the present invention, the process gas introduced through the process gas inlet line is raised in temperature by the heat of the inner wall of the reactor.

In an embodiment of the present invention, the temperature of the process gas is 150 ° C. or more, and the inner wall and the outer wall of the reactor have a cylindrical shape and have a sealed structure.

The plasma gas scrubbing apparatus according to the present invention heats the process gas to the plasma torch heat source by raising the incoming plant gas along the inner wall of the lower reactor. Thereafter, the heated process gas and water particles sprayed through the nozzle are mixed at the front end of the plasma reactor to induce evaporation of the water particles. This effectively lowers the temperature of the actual plasma reactor and at the same time prevents condensation of water due to the low temperature process gas, thereby maximizing the scrubbing effect. In addition, by maintaining the process gas at 150 degrees or more as an indirect heat source of the plasma (that is, the heat generated in the reactor inner wall), it serves to maintain the mixed water vapor in the superheated steam state, when the steam injection Maintaining the original superheated steam condition allows for better mixing with the process gas, resulting in improved process gas treatment efficiency. Furthermore, the temperature of the reactor is relatively lower due to the heating of the process gas in contact with the reactor, thereby reducing the reactor life due to the high temperature and the risk of operation due to the high temperature.

1 is a schematic diagram of an atmospheric pressure plasma scrubbing apparatus according to an embodiment of the present invention, Figure 2 is a perspective view thereof.
3 is a step diagram of an atmospheric pressure plasma scrubbing method according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. The following embodiments are provided as examples to ensure that the spirit of the present invention to those skilled in the art will fully convey. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, etc. of the components may be exaggerated for convenience. Like numbers refer to like elements throughout.

The atmospheric pressure plasma scrubbing apparatus according to the present invention uses a plasma generated by a microwave to decompose and treat a reaction gas such as waste gas. The process gas temperature, which is a waste gas, is contacted with a reactor inner wall by contacting the process gas flowing into the reactor. Raise. That is, the present invention solves the problem of flocculation of the process gas by heating the process gas before the plasma reaction with a plasma heat source and supplying a predetermined amount of thermal energy before the reaction, and further, the problem of lowering the scrubbing efficiency due to the condensation of water. .

The process gas which naturally rises as the temperature rises is then mixed with the water particles sprayed through the nozzle at the front of the reactor. That is, according to the mixing of the process gas and the water raised to the level of 150 ℃ or more, the water is not condensed again (that is, evaporated vapor state), and flows into the reactor with the process gas.

In particular, the inventors of the present invention, when adding water vapor in order to enhance the effect of the conventional plasma treatment, the water vapor meets the cold waste gas and immediately changes into a saturated water vapor state or fine water droplets form, so that it does not diffuse properly in the plasma chamber, thereby Attention has been paid to the problem that the plasma becomes unstable and, as a result, the processing efficiency of the process gas is lowered. In order to solve this problem, the present invention is to maintain the process gas to the superheated steam (superheated steam) state by maintaining the process gas at 150 degrees or more as an indirect heat source (ie heat generated in the inner wall of the reactor) of the plasma This maintains the initial superheated steam during steam injection, allowing it to be better mixed with the process gas, thereby improving the processing efficiency of the process gas.

Hereinafter, an atmospheric pressure plasma scrubbing apparatus according to an embodiment of the present invention will be described in detail.

1 is a schematic diagram of an atmospheric pressure plasma scrubbing apparatus according to an embodiment of the present invention, Figure 2 is a perspective view thereof.

1 and 2, the atmospheric pressure plasma scrubbing apparatus 100 according to the present invention includes a microwave generating unit (not shown) such as a magnetron, and a waveguide 110 to which microwaves oscillating from the microwaves are applied. . In one embodiment of the present invention, the waveguide is simultaneously reduced in width and width by a predetermined level, and in particular, through simultaneous reduction in width and width, the microwave density is increased.

The waveguide 110 is provided with a dielectric tube 120 that is connected to and penetrates the waveguide 110. The dielectric tube 120 is a quartz tube, and its inner wall is coated with a material such as boron nitride having high heat resistance to withstand a high temperature flame. When the torch gas is supplied into the dielectric tube 120, the dielectric tube ( An ignition device (not shown) provided in the 120 supplies initial electrons necessary for discharge, thereby generating an atmospheric pressure plasma in the dielectric tube 120. A swirl gas is supplied to the surface of the dielectric tube 120 to prevent the hot plasma torch from directly contacting the dielectric tube.

In one embodiment of the present invention, the process gas scrubbing device is connected to the bottom of the waveguide 110, and includes an outer wall (130b) and the inner wall (130a) spaced at a predetermined interval, the dielectric tube 120 is provided therein Which comprises a reactor 130. That is, in the present invention, the reactor 130 having a double barrier rib formed of a metal material is provided on the outside of the dielectric tube 120. In one embodiment of the present invention, the reactor inner wall 130a and the outer wall 130b have a predetermined distance. Keep it spaced apart. Therefore, a process gas flows into the space between the inner wall 130a and the outer wall 130b to come into contact with the inner wall 130a, thereby heating the process gas by the inner wall 130a, and the heated process gas Will rise above the reactor. In one embodiment of the present invention, the reactor 130 is cylindrical, but the scope of the present invention is not limited thereto. At this time, the temperature of the reactor inner wall (130a) is relatively lowered due to the heating of the process gas in contact with the inner wall (130a). This solves the problem of shortening the reactor life due to high temperature and the danger of operation due to high temperature.

The reactor inner wall 130a is a wall separating a high temperature internal plasma reaction region (ie, an internal dielectric tube) and an external process gas inflow path. In an embodiment of the present invention, the inner wall 130a is formed of a stainless steel material. The same metal material, but in addition, it may be made of one or more metals selected from the group consisting of aluminum and iron.

The reactor outer wall 130b is a sealing structure that blocks the space between the inner wall 130a and the outer wall 130b from the outside air, and the outer wall 130b has a lower end from an external device (for example, a semiconductor processing apparatus 200). The process gas inlet line 140 into which the process gas to be processed is introduced is connected. In addition, the upper end of the outer wall (130b) is connected to the process gas discharge line 150 is discharged to the process gas flows to the outside, the process gas discharge line 150 is extended again, the waveguide 110 on the top It is provided, and is connected to the injection unit 160 for injecting water and process gas into the waveguide 110. That is, the injection unit 160 is provided with a nozzle for injecting water, and provides a path through which water flows into the waveguide. In addition, the injection unit 160 is also connected to a process gas discharge line 150 through which the heated process gas flows, and the process gas discharged from the process gas discharge line 150 is injected into the injection unit 160. Is mixed with water. In the present invention, since the temperature of the process gas is increased by using a heat source of the plasma torch, the temperature of the water flowing into the injection unit 160 is lowered again, thereby preventing the problem of water condensation and scrubbing efficiency. Can be increased.

Particularly, in one embodiment of the present invention, the process gas in contact with the reactor inner wall 130a rises to a level of 100 to 150 ° C., and the process gas rises up as the temperature rises, so that the process gas is pumped separately. It is introduced upstream of the reactor system without any means such as such. Here, the reactor system refers to a region in which gas is decomposed by the plasma reaction, and includes both the waveguide 110, the dielectric tube 120, and the reactor 130 at the bottom of the waveguide.

Water in the water vapor state or the particulate state is directly injected upstream of the process gas by the elevated temperature of the process gas injected into the dielectric tube 120 according to an embodiment of the present invention. As a result, the water previously sprayed in the vapor state is decomposed into radical components by plasma generated in the dielectric tube, and the radicals amplify the decomposition of the reaction gas such as CF 4, and also C, F, etc., radicals of the decomposed CF 4. In combination with a stable material.

3 is a step diagram of an atmospheric pressure plasma scrubbing method according to an embodiment of the present invention.

Referring to FIG. 3, first, a process gas to be treated is brought into contact with an inner wall of a reactor in which a plasma reaction occurs, thereby raising a temperature. In order to prevent a problem that the process gas in contact with the inner wall is discharged to the outside, in one embodiment of the present invention is provided with a reactor outer wall spaced apart from the inner wall at a predetermined interval, the process gas is introduced between the predetermined intervals.

Thereafter, the process gas whose temperature is increased according to the plasma heat source is introduced into the front end of the waveguide where the plasma is generated, together with the water vapor, and then introduced into the waveguide together with the water vapor to become plasma. Through this configuration, the gas scrubbing method using the atmospheric pressure plasma can produce an effective plasma decomposition effect, and can prevent the efficiency decrease due to water vapor condensation.

Although the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various changes or modifications can be made within the spirit and scope of the invention, and such changes or modifications are consequently claimed. You will have to belong to the range.

100: atmospheric plasma scrubbing device
110: waveguide
120: genetic tube
130: reactor
130a: reactor inner wall
130b: reactor outer wall
140: process gas inlet line
150: process gas discharge line

Claims (5)

In the atmospheric plasma gas scrubbing apparatus,
A microwave generator;
A waveguide to which microwaves generated from the microwave generator are applied;
A dielectric tube connected to the waveguide and generating a plasma by microwaves applied in the waveguide to discharge the torch to the outside;
A reactor connected to the bottom of the waveguide, the outer wall and the inner wall spaced at predetermined intervals, and the dielectric tube being provided inside the inner wall;
A process gas inlet line connected to a lower end of the outer wall to receive a process gas to be treated from the outside;
A process gas discharge line connected to an upper end of the outer wall to discharge the introduced process gas; And
It is provided on the top of the waveguide, and includes an injection unit for injecting water into the waveguide, wherein the process gas discharge line is connected to the injection unit, after the water and the process gas is mixed in the injection unit, the waveguide Atmospheric pressure plasma gas scrubbing apparatus, characterized in that flowing into. The method of claim 1,
The reactor inner wall is an atmospheric pressure plasma gas scrubbing apparatus, characterized in that made of at least one metal selected from the group consisting of stainless steel, aluminum and iron. The method of claim 1,
Atmospheric pressure plasma gas scrubbing apparatus, characterized in that the temperature of the process gas introduced through the process gas inlet line is increased by the heat of the inner wall of the reactor. The method of claim 3,
Atmospheric pressure plasma gas scrubbing apparatus, characterized in that the temperature of the process gas is 150 ℃ or more. The method of claim 1,
The reactor inner wall and the outer wall is a cylindrical shape, atmospheric pressure plasma gas scrubbing apparatus, characterized in that the sealing structure.

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