KR20090075098A - Gas scrubber - Google Patents

Abstract

A gas scrubber is provided to improve collecting capabilities of water-soluble gas and powder by extending contact area and contact time of gas, prevent corrosion of exhaust duct and pipe by installing an instant drying part, and reduce the volume ratio of the gas scrubber by integrating components of the gas scrubber. A gas scrubber comprises a manifold(100), a burner(110), a burning chamber(200), a wet column(400), an instant drying part(500), and a drain tank(600). The manifold sends harmful gas flown in to the burning chamber. The burner is installed on one side of the manifold to ignite the combustion gas by flowing air or oxygen into combustion gas. The burning chamber is located under the manifold to burn or thermally decompose harmful gas flown in from the manifold using a flame generated from the burner. The wet column includes a baffle board(410) and an absorber(420) which extend a flow path of the gas passing through the burning chamber to increase contact area and contact time of the gas. The instant drying part supplies external air into the wet column through an external air inlet to lower relative humidity of the gas passing through the wet column. The drain tank is located under the burning chamber and wet column and collects and drains wastewater and powder generated while the gas passes through the burning chamber and wet column.

Description

Gas scrubber

The present invention relates to a gas scrubber, and more particularly, a manifold which sends inflowing harmful gas to a burning chamber, a burner installed inside the manifold and ignited by injecting combustion gas and air, and positioned below the manifold. And a burning chamber which decomposes or burns harmful gas introduced from the manifold by using a flame generated from a burner, and a baffle board and an absorber which increase the contact area and the contact time by lengthening the flow path of the gas passing through the burning chamber. Wet column provided with the external air to the gas passing through the wet column to lower the relative humidity, the drying unit and the burning chamber and the lower portion of the burning column and the gas generated while passing through the burning chamber and the wet column A gas scrubber comprising a drain tank for draining waste water and powder.

The present invention relates to a gas scrubber, and more specifically, by using a wet column as a baffle lattice structure, the passage of harmful gas is increased to increase the area and time for the harmful gas to contact water, thereby improving the efficiency of removing the harmful gas and the ability to collect powder. The present invention relates to a gas scrubber that can reduce installation space by improving and reducing the number of units by integrating the components of the gas scrubber.

Semiconductor devices are manufactured through various manufacturing processes such as oxidation, etching, deposition, and photo processes, and these processes are supplied with toxic chemicals and chemical gases. For example, chemical gases such as silane, ammonia, nitric oxide, arsine, pocipine, diboron, boron trichloride are used.

These chemical gases are so toxic that if they are used in the process and released into the atmosphere, they can have a fatal effect on the human body, cause a fire due to spontaneous ignition or cause environmental problems.

In order to solve these problems, various types of gas scrubbers have been proposed, and gas scrubbers are roughly classified into a wetting method and a burning method.

Wetting type scrubber is a structure that cleans and cools harmful gas using water, and has a relatively simple configuration, so it is easy to manufacture and can be large-capacity. However, insoluble gas cannot be treated. It is inappropriate for the treatment of exhaust gas containing hydrogen groups.

The burning type scrubber has a structure in which a harmful gas passes through a burner such as a hydrogen burner to directly burn or a high temperature chamber using a heat source to indirectly burn the exhaust gas through the burner. This burning scrubber has an excellent effect on the treatment of flammable gases, but is inadequate for the treatment of gases that do not burn well.

Accordingly, a mixed gas scrubber combining a wetting scrubber and a burning scrubber is in use.

The mixed gas scrubber first has a structure in which the exhaust gas is first burned in the combustion chamber to remove the ignition gas and the explosive gas, and then secondarily contained in the water tank to dissolve the water-soluble toxic gas in water.

However, the conventional mixed gas scrubber as described above has a problem in that it occupies a large installation area by being configured in the form of connecting the vertical combustion chamber and the vertical wetting chamber separated from each other by a connecting pipe.

In addition, the conventional mixed gas scrubber has a disadvantage in that frequent maintenance is required as a large amount of powder is generated in a portion that comes into contact with water through the combustion chamber. The maintenance of the gas scrubber is very disadvantageous in terms of productivity since it immediately leads to the shutdown of the main process equipment which emits the exhaust gas.

In addition, the conventional mixed gas scrubber has a problem of corroding the exhaust pipe at the site where the water molecules combined with the noxious gas in contact with the air by chemical bonding upon contact with water. The result is uneconomical because it requires expensive exhaust pipes that are corrosion resistant.

In addition, the conventional mixed gas scrubber is limited in size, there is a limit in the treatment capacity of harmful gases. That is, the gas scrubber is limited in size as it is required to be installed in a small area, the conventional burning chamber has to have a small inner diameter in order to obtain a temperature sufficient to burn the exhaust gas, and a long length for sufficient combustion There is a limitation in processing a large amount of exhaust gas at one time.

There is also a need for preventing the deposition of powder in conventional gas scrubbers and for improving water treatment efficiency.

The present invention devised to solve the problems of the prior art as described above is to arrange the wet column having a plurality of baffle board to increase the flow path of the gas to increase the contact area and the contact time of the gas to increase the ability to collect water-soluble gas and powder The drying unit is installed to prevent the corrosion of exhaust ducts and pipes while improving the relative humidity by introducing external air into the gas that has passed through the wet column, and at the same time, constructing a gas scrubber by integrating components (parts) of the gas scrubber. It is an object of the present invention to provide a gas scrubber which can reduce the volume fraction of the gas scrubber by simplifying the unit and reducing the number thereof.

The object of the present invention is a manifold for sending the harmful gas flowing into the burning chamber; A burner installed at one side of the manifold and ignited by introducing combustion gas and air (oxygen); A burning chamber positioned below the manifold and burning or pyrolyzing harmful gas introduced from the manifold using a flame generated from a burner; A wet column having a baffle board and an absorber for increasing a contact area and a contact time by lengthening a flow path of gas passing through the burning chamber; An instant drying unit supplying external air through an outside air inlet to lower the relative humidity of the gas passing through the wet column; And a drain tank positioned below the burning chamber and the wet column and including a drain tank for collecting and draining the waste water and powder generated while the gas passes through the burning chamber and the wet column.

The gas scrubber of the present invention preferably further includes a cooling chamber connected to one side of the wet column and cooling the gas passing through the burning chamber to be sent to the wet column.

The gas scrubber of the present invention may include a first unit integrating a manifold, a burner and a burning chamber, a second unit integrating a wet column and a drain tank, and a third unit including an instantaneous drying unit.

One side of the manifold preferably further includes a combustion gas inlet and an air (oxygen) inlet.

It may further include an injection nozzle for injecting water to the top or side of the wet column.

The baffle board may further include a plurality of holes penetrating the baffle board.

The absorber is preferably made of Teflon.

In addition, the drain tank is preferably a Teflon coating.

Therefore, the gas scrubber of the present invention improves the collection efficiency of water-soluble gas and powder by increasing the contact area and the contact time of water and gas using a baffle board and an absorber, and supplying external air to the gas passed through the wet column. Lowering relative humidity prevents corrosion of exhaust ducts and pipes by corrosive gases, while simplifying units and reducing the number of units to reduce the volume ratio to increase space utilization and investment costs in semiconductor manufacturing processes. It can be effected.

The terms or words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of a gas scrubber according to the present invention, Figure 2 is a perspective view of a gas scrubber according to the present invention.

Gas scrubber of the present invention includes a manifold (100, manifold), burner 110, burning chamber 200, cooling chamber 300, baffle board (410, baffle board) and absorber (420, absorber) Wet column (400, wet column), instantaneous drying unit 500 and the drain tank 600, and the like.

The manifold 100 serves to send the harmful gas introduced through the harmful gas inlet 190 to the burning chamber 200 and preferably forms a vortex. The burner 110 exists inside the manifold 100, and when the combustion gas is introduced in advance and the signal is received from the main equipment to proceed with the process, the igniter 120 (igniter) ignites the burner and whether the ignition is flamed (flame) ) Is checked through the sensor 130.

One side of the manifold may be a combustion gas inlet 140 and air (oxygen) inlet 150. LPG or LNG is preferred as the combustion gas, but is not limited thereto.

The harmful gas passing through the manifold 100 forms a vortex to enter the burning chamber 200 in the lower portion of the manifold, and the harmful gas is burned or pyrolyzed by the flame and heat of the burner.

Pyrolytic gases include H ₂ , SiH ₄ , O ₃ , TEOS [(C ₂ H ₅ O) ₄ Si], TEB [B (C ₂ H ₅ ) ₃ ], TEPO [P (OC ₂ H ₅ ) ₃ ], TiCl ₄ , TDMAT (Ti [N (CH ₃ ) ₂ ] ₄ ), TCE (C ₂ HCl ₃ ), DCS (SiH ₂ Cl ₂ ), NH ₃ , NF ₃ , NO, N ₂ O, PH ₃ , WF ₆ , AsH ₃ , As, VOCs, and the like.

In addition, examples of gases combustible by LPG or LNG include NF ₃ , CF ₄ , C ₂ F ₆ , C ₃ F ₈ , CHF ₃ , SF ₆ , and VOCs.

Aqueous gases include HCl, DCS (SiH ₂ Cl ₂ ), NH ₃ , ClF ₃ , SiF ₄ , F ₂ , HF, SiCl ₄ , WF ₆ , TiCl ₄ , NH ₄ Cl, TDMAT (Ti [N (CH ₃ ) _{2 4} ), AlCl ₃ , Cl ₂ , TCA (C ₁₀ H ₄ Cl ₆ O ₄ ), BCl ₃ , HBr, SO ₂ , B, BF ₃ , TEOS ((C ₂ H ₅ O) ₄ Si), TiF ₄ These water-soluble gases are mainly removed while passing through the wet column.

It is preferable to install a shower nozzle 230 around the burning chamber 200 to prevent heat transfer to the outer wall 250 by the flame in the burning chamber.

The gas passing through the burning chamber 200 may pass through the cooling chamber 300 before entering the wet column 400 or entering the wet column 400. 1 and 2 show a case where the cooling chamber 300 is present.

The cooling chamber 300 is connected to one side of the wet column 400 and serves to cool the gas passing through the burning chamber 200 and send it to the wet column.

An injection nozzle 330 for injecting water exists in the upper or side surface of the cooling chamber 300 to inject water into fine particles and to collect and purify the powder contained in the noxious gas by the injected fine water particles. Aqueous harmful gas is dissolved and introduced into the drain tank 600.

The gas passing through the cooling chamber 300 passes through the wet column 400, and the wet column includes a baffle board 410 and an absorber 420 for lengthening a passage of harmful gas and increasing a contact area and a contact time. Further provided with an injection nozzle 430 for injecting water in the upper or side of the wet column.

The baffle board 410 is preferably installed in multiple in order to lengthen the flow path of the gas (two in Figure 1, three baffle boards are shown in Figure 2) alternately arranged baffle board 410 gas It is preferable to lengthen the flow path of.

Meanwhile, the baffle board 410 may have a plurality of holes (not shown) penetrating the baffle board. Holes in the baffle board allow water to be sprayed evenly through this hole.

The absorber 420 is installed to fill the inner space of the wet column 400, and the support plate 440 is present at the lower portion of the wet column to prevent the absorber from falling down. The support plate 440 may be formed integrally with the column.

The absorber 420 is made of polypropylene or Teflon, and preferably made of Teflon to prevent corrosion by corrosive gas. In addition, it may be formed in the shape of a spherical, cylindrical, tetrahedral, hexahedral, octahedron, icosahedral, or the like of about several mm to several cm in size, but is not limited in size or shape.

Since the absorber has a hole (empty space) therein and the gas passes through the hole present in the absorber, the contact area and the contact time are increased to increase the removal efficiency of the water-soluble gas and powder.

Wet column 400 consists of one or more columns and two columns are shown in FIG. 1. As shown in FIG. 1 and FIG. 2, a plurality of columns may be arranged in parallel rather than in series to take a long flow path of gas without increasing the volume of the equipment.

In this case, it is preferable that a hole exists to allow gas to pass through one side of the column to which the column is connected, and it is preferable to coat the inner wall of the wet column with Teflon to prevent corrosion.

According to the results of the applicant's experiment, the powder collecting capacity of the gas scrubber applying the wet column of the conventional cylindrical two-stage structure is 90%, whereas the powder collecting ability of the gas scrubber of the present invention with the baffle board and the absorber is Up to 99% .

The instant drying unit 500 has an outside air inlet 510 and lowers the relative humidity by introducing the outside air through it. That is, the external air is supplied to the gas passing through the wet column 400 to prevent moisture condensation, thereby preventing corrosion of the exhaust duct or the pipe by the corrosive gas.

In addition, in case the exhaust pressure drops, a safety setting limit value is sensed and an actuator valve (not shown) capable of automatically closing is installed to prepare for a risk.

The drain tank 600 is positioned below the burning chamber 200, the cooling chamber 300, and the wet column 400, and the harmful gas is connected to the burning chamber 200, the cooling chamber 300, and the wet column 400. It collects and drains the wastewater and powders generated through the passage.

To this end, it is preferable to include a drain pump 610 and the circulation pump 620.

The drain tank 600 may be made of stainless steel and preferably coated with a Teflon coating on the inner wall of the tank to prevent corrosion.

The gas scrubber of the present invention can simplify the unit constituting the equipment in order to reduce the equipment size and increase space utilization in accordance with the semiconductor FAB environment.

That is, it is possible to manufacture a gas scrubber comprising a first unit in which the manifold and the burner are integrated, a second unit integrating the wet column and the drain tank, and a third unit including the instant drying unit, which is 33% compared to the existing one. Brought about a decrease in volume ratio.

The first unit may further include an igniter 120, a flame sensor 130, a combustion gas inlet 140, and an air (oxygen) inlet 150.

The burning chamber 200 is included in the first unit or the second unit.

The second unit further includes a cooling chamber 300 and injection nozzles 330 and 430 for injecting water. The wet column includes a baffle board and an absorber and is integrally formed with a drain tank existing below.

The instantaneous drying unit of the third unit introduces external air to the one side of the instantaneous drying unit through the outside air inlet 510.

The gas scrubber manufactured as described above is simple because there are few separation units, and the size of the equipment can be reduced according to the semiconductor FAB environment to increase the space utilization rate, thereby reducing the investment cost by installing more equipment in the same space.

In addition, A / S is easy by simplifying and reducing the number of units constituting the equipment.

Although the present invention has been shown and described with reference to the preferred embodiments as described above, it is not limited to the above embodiments and those skilled in the art without departing from the spirit of the present invention. Various changes and modifications will be possible.

The present invention increases the efficiency of the treatment of harmful gases by installing a baffle board and an absorber to increase the gas flow path, and prevents the corrosion of the exhaust duct and the pipe by the corrosive gas through the instantaneous drying unit, and at the same time the unit constituting the equipment The present invention relates to a gas scrubber which has a reduced volume ratio by simplifying and reducing the number thereof, and can be used in an apparatus and a process requiring treatment of harmful gases including a semiconductor manufacturing process.

1 is a block diagram of a gas scrub according to the present invention.

2 is a perspective view of a gas scrubber according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100: manifold 110: burner

200: burning chamber 300: cooling chamber

400: wet column 410: baffle board

420: Absorber 500: Instantaneous drying unit

510: outside air inlet 600: drain tank

Claims (8)

A manifold that sends the incoming harmful gas to the burning chamber; A burner installed at one side of the manifold and ignited by introducing combustion gas and air (oxygen); A burning chamber positioned below the manifold and burning or pyrolyzing harmful gas introduced from the manifold using a flame generated from a burner; A wet column having a baffle board and an absorber for increasing a contact area and a contact time by lengthening a flow path of gas passing through the burning chamber; An instant drying unit supplying external air through an outside air inlet to lower the relative humidity of the gas passing through the wet column; And A gas scrubber positioned below the burning chamber and the wet column and including a drain tank for collecting and draining waste water and powder generated while the gas passes through the burning chamber and the wet column. The method of claim 1, And a cooling chamber connected to one side of the wet column and cooling the gas passing through the burning chamber to the wet column. The method of claim 1, The gas scrubber comprises a first unit integrating a manifold, a burner and a burning chamber, a second unit integrating a wet column and a drain tank, and a third unit including an instantaneous drying unit. The method according to any one of claims 1 to 3, Gas scrubber further comprises a combustion gas inlet and air (oxygen) inlet on one side of the manifold. The method according to any one of claims 1 to 3, Gas scrubber further comprises a spray nozzle for injecting water to the top or side of the wet column. The method according to any one of claims 1 to 3, The baffle board further comprises a plurality of holes through the baffle board. The method according to any one of claims 1 to 3, The absorber is a gas scrubber consisting of Teflon. The method according to any one of claims 1 to 3, The drain tank is a gas scrubber is Teflon coating.

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