KR101762302B1 - High corrosion resistant SiC honeycomb combustion materials for incineration of nondegradable hazardous gas - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a combustor material for incinerating refractory noxious gas and an incinerator method using the combustor material. More particularly, the combustor material 100 provided in a scrubber system for burning off- A combustor body 110 in which an exhaust port 150 is formed in which a waste gas inlet 111, a waste gas inlet 112 and an oxidant inlet 113 are formed and an exhaust gas is exhausted at the other end thereof; And a ceramic porous body combustor in which the waste gas is burned by a flame formed inside the ceramic porous body 140 provided inside the combustor body, wherein the ceramic porous body has a porosity of 10 5% and b) C) a corrosion resistance test using 53 Wt% HF at 25 DEG C of not more than 0.1 mg / cm < ² > · month, and an energy-saving corrosion resistance SiC honeycomb combustor material.

Description

TECHNICAL FIELD [0001] The present invention relates to a corrosion resistant SiC honeycomb combustor for incineration of harmful gas,

The present invention relates to a combustor material (110) for burning refractory noxious gas and an incinerator method using the combustor material (110). More particularly, the present invention relates to a process for producing a refractory process gas (PFCs (CF ₄ , C ₂ F ₆ , C ₂ F ₄ , SF ₆ and NF ₃ ) used in semiconductor and display manufacturing processes, The present invention relates to a combustible SiC honeycomb combustor material, which is a combustor material (110) provided in a system for burning harmful noxious gas.

PFCs gas, which is widely used in semiconductor and display manufacturing processes, is a greenhouse gas that causes global warming. The warming index has to be several thousand to tens of thousands times higher than that of CO ₂ and must be released into the atmosphere through appropriate treatment facilities.

Generally, various types of reactive gases used for forming a thin film on a wafer or for etching in a semiconductor manufacturing process are explosive, toxic, and suffocating and released into the atmosphere as they are, which is not only harmful to the human body but also causes global warming and environmental pollution . Accordingly, the exhaust line of the semiconductor facility is provided with a scrubber, which is a gas purifying device for safely decomposing and removing the refractory noxious gas and discharging it to the atmosphere. These refractory noxious gases are diluted to a concentration of several hundreds to several thousands ppm or less together with nitrogen (N ₂ ), a working oil of a vacuum pump used to maintain a negative pressure in the process, and then introduced into the scrubber. Hereinafter, a state in which a refractory noxious gas is diluted with an inert gas is defined as a waste gas.

Recalcitrant of PFCs, SF _6, NF _3, CF ₄ For 1600 ℃, SF ₆ are 1200 ℃, NF ₃ are known to be thermally decomposed at a temperature above 800 ℃. PFCs, SF ₆ , and NF ₃ are combined with fluorine and are discharged in the form of fluorine (F ₂ ) and hydrofluoric acid (HF) after decomposition treatment. These are also toxic explosive gases that require post- And then discharged. As a treatment method of the waste gas by the scrubber, there are currently a combustion incineration method, a catalytic decomposition method, a thermal plasma incineration method, and an electrolysis method.

1 schematically shows a conventional scrubber system 1 for waste gas treatment. 1, the scrubber 1 for semiconductor waste gas treatment includes a plurality of waste gas inlet ports 112 connected to a semiconductor manufacturing process line, a burner 5 connected to the waste gas inlet port 112, A water tank tank 4 connected to the lower end of the combustor material 110 to allow the powder generated in the combustor material 110 to be trapped and settled in water, And a wet tower 3 which is joined together with the water tank 4 to treat fine powder and water-soluble gas that have passed through the combustor material 110 with water. Here, the combustor material 110 and the wet tower 3 may be interconnected by separate connecting pipes, and a discharge pipe is formed on the upper part of the wet tower 3.

The scrubber system 1 for semiconductor waste gas treatment is supplied with various types of waste gas from the semiconductor manufacturing process line through the waste gas inlet 112. The waste gas supplied through the waste gas inlet 112 is supplied to the combustor material 110 through the burner 5. The waste gas inside the combustor material (110) is burned by the burner (5), and a large amount of hydrofluoric acid, fluorine and powder are produced by such combustion. The relatively heavy powder among the above-mentioned powders falls down to the bottom due to gravity, and the dropped powder is precipitated in water in the lower tank 4. On the other hand, the relatively light fine powder that has not fallen into the water tank 4 moves to the wet tower 3 through a connection pipe connected between the combustor material 110 and the wet tower 3. The fine powder moved to the wet tower 3 is once again collected by water in the wet tower 3, and the collected fine powder falls again into the water tank 4 and is precipitated in water. Of course, the purified waste gas passing through the wet tower 3 is discharged to the atmosphere through the discharge pipe. In order to incinerate the waste gas, it is necessary to oxidize the waste gas at a high temperature of 1,600 ° C. (CF ₄ case) or higher. As described above, the waste gas is diluted with an inert gas (mostly N ₂ ) of 99% There is a problem in that an inert gas which does not need to be treated is also required to be heated, and thus there is a problem that not only the treatment efficiency but also energy utilization efficiency is very low.

1, fuel and oxidant (oxygen) are injected through a nozzle attached to a combustor material 110 existing inside a scrubber through a fuel inlet 111 and an oxidant inlet 113, as in the prior art, The gas is supplied to the material 110 and then ignited to form a nozzle-attached flame, and the waste gas is introduced into the combustor material 110 through a separate additional waste gas inlet 112. [ The waste gas injected into the combustor material is heated and oxidized along with the flame or at an oblique flow rate. In order to generate a swirl for the purpose of enhancing the mixing or to allow the waste gas to hit a high temperature flame, (Cross-flow method) in which the direction is shifted from the flow direction of the waste gas. However, even when this method is applied, It is difficult for the combustion gas and the waste gas to be mixed sufficiently in the chamber. Since the flow rate of the waste gas is generally larger than the flow rate of the combustion gas, a large momentum of the waste gas causes the flame to become unstable or even extinguishes, . In this case, it is necessary to use additional fuel and oxidizing agent to form stable flame and increase the treatment efficiency accordingly. This causes inefficiency of utilization of energy and the waste gas can not pass through the flame of high temperature due to the momentum of the waste gas, Resulting in deterioration of the decomposition efficiency.

In order to solve these problems, Korean Registered Patent No. 1494623 of Korea Institute of Energy Research (KOKAI) discloses a combustion apparatus for incinerating harmful gas, a method of incinerating the combustor material, and an incinerator system having the combustor material. More particularly, the present invention relates to a combustor material provided in a scrubber system for incineration of waste gas, comprising a fuel inlet, a waste gas inlet, and an oxidant inlet formed at one end thereof, A combustion chamber; And a ceramic porous body combustor provided in the combustor body and formed of a ceramic porous body and having a flame formed therein so that the waste gas is incinerated, and a burning apparatus for incinerating a refractory toxic gas .

Japanese Patent Application Laid-Open No. 2009-226350 discloses a honeycomb structure composed of a porous ceramic having a ceramic powder and a binder for bonding ceramic particles constituting the ceramic powder. Japanese Unexamined Patent Publication (Kokai) No. 1996-061874 discloses a honeycomb heat accumulator in which a plurality of honeycomb structures are piled up and stacked in an exhaust gas by alternately passing an exhaust gas and an object gas through a flow path formed of through holes, Characterized in that the honeycomb structural body is constituted by a honeycomb structured body made of corrosion resistant ceramics and the side in contact with the exhaust gas is constituted by a honeycomb structural body in which the main crystal phase is made of cordierite, Japanese Patent Laid-Open Publication No. 2009-202143 discloses a heat accumulator having a plurality of cells penetrating in an axial direction, which are divided by barrier ribs, and adjacent cells are opposite to each other, or at the other end An eye-sealed ceramic honeycomb structure, comprising at least two And a connecting portion formed on each of at least two of the segment portions adjacent to the segment portion and bridging the at least two adjacent segment portions so that the number of the connecting portions is smaller than the number of cells of the segment portion connected to the connecting portion However, there is no description about a ceramic porous body for treating a PFC waste gas having a high corrosivity while forming a flame in a porous body.

Korea Patent No. 1494623 Japanese Patent Application Laid-Open No. 2009-226350 Japanese Patent Application Laid-Open No. 1996-061874 Japanese Laid-Open Patent Publication No. 2009-202143

SUMMARY OF THE INVENTION It is an object of the present invention to provide a ceramic porous body combustor in which the waste gas is incinerated by a flame formed inside a ceramic porous body provided inside a combustor body for incinerating refractory noxious gas, The present invention also provides an energy-saving anti-corrosive SiC honeycomb combustor material to which a ceramic porous body having high porosity, room temperature thermal conductivity and corrosion resistance is applied.

In addition, it has a high plastic density and low porosity compared to existing combustor materials (foam, mesh, felt), and it has excellent thermal conductivity due to its excellent thermal conductivity and excellent corrosion resistance against fluorine gas, The present invention also provides a method of manufacturing a honeycomb material for an energy-saving corrosion-resistant SiC honeycomb combustion device.

The present invention also provides a manufacturing method of a high-density energy-saving type corrosion-resistant SiC honeycomb combustor using an extrusion molding method and a constant temperature / humidity drying method.

In addition, for the purpose of increasing energy utilization efficiency and forming a high-temperature flame, combustion is performed inside the ceramic porous body without using an additional device such as a heat exchanger, whereby heat recirculation occurs due to conduction and radiation heat transfer of the porous body itself And which can ultimately achieve high-temperature combustion with an excess enthalpy, and to provide a corrosion-resistant SiC honeycomb combustor material for incineration treatment of noxious harmful gas.

In the incineration of the decomposable noxious gas, the waste gas which has been over-diluted with an inert gas (mainly N ₂ ) is mixed with the fuel and the oxidizer, and then supplied to the inside of the porous body to be incinerated, It is an object of the present invention to provide a material for a corrosion resistant SiC honeycomb combustor which can improve the treatment efficiency of waste gas and can be treated with only a small amount of fuel, .

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings.

The combustor 100 provided in the scrubber system for burning offgas is provided with a fuel inlet 111, a waste gas inlet 112 and an oxidant inlet 113 at one end and a waste gas A combustor body 110 having a discharge port 150 through which exhaust gas is burned; And a ceramic porous body combustor in which the waste gas is burned by a flame formed inside the ceramic porous body (140) provided inside the combustor body, wherein the ceramic porous body has a) a porosity of 10 5% and b ) At room temperature thermal conductivity of not less than 80 W / m · K, and c) less than 0.1 mg / cm ² · month in corrosion resistance test using 53 wt% HF at 25 ° C. Can be achieved as a corrosion-resistant SiC honeycomb combustor material.

The ceramic porous body may be manufactured by mixing 30 to 90 wt% of silicon carbide, 0 to 15 wt% of carbon, 5 to 25 wt% of organic binder, and 5 to 30 wt% of water.

The ceramic porous body may be extrusion-molded.

The ceramic porous body may be characterized in that it undergoes a primary drying process in which the humidity of the molded body is gradually lowered at a temperature of 50 to 100 DEG C for 100 to 170 hours in a constant temperature and humidity chamber.

The ceramic porous body may be characterized in that it is subjected to a secondary drying step of drying the molded body at a temperature of 100 to 150 ° C for 1 to 30 hours in a high temperature drying chamber.

The ceramic porous body may be characterized in that the ceramic porous body is subjected to a heat treatment in a high temperature furnace at a temperature of 500-700 ° C and in an atmosphere of argon, nitrogen or vacuum for 1 to 24 hours.

The ceramic porous body may be characterized in that firing is carried out in a range of 1 to 10 hours under a gas atmosphere of any one of 1900-2200 ° C, vacuum, argon or nitrogen in a firing furnace.

In addition, the ceramic porous body may include a honeycomb shape of 50-500 CPSI (Channel Per Square Inch).

A premixer in which fuel flowing through the fuel inlet, waste gas flowing through the waste gas inlet, and oxidant flowing through the oxidant inlet are mixed; And a distributor provided between the pre-mixer and the ceramic porous body combustor to uniformly introduce the gas mixed in the pre-mixer into the ceramic porous body combustor.

And a pretreatment / dust collecting device for separating and discharging impurity particles having a specific particle size or more contained in the waste gas.

And a concentrating device for concentrating the waste gas to separate and remove a part of the inert gas contained in the waste gas.

According to an embodiment of the present invention, it is possible to achieve high process efficiency and high energy utilization efficiency in the design of a combustor for incinerating refractory noxious gas, and all the waste gases can be decomposed So that it is possible to sufficiently reach the high temperature that is present.

In addition, if combustion is performed inside the ceramic porous body without using an additional device such as a heat exchanger, heat recirculation occurs due to conduction and radiative heat transfer of the porous body itself, and ultimately, excess enthalpy burning can be easily achieved .

In the incineration of the decomposable noxious gas, the waste gas which is over-diluted with the inert gas is mixed with the fuel and the oxidizer, and is supplied to the inside of the porous body for incineration, whereby the conventional combustion technology can be achieved by the internal heat recirculation It is possible to improve the treatment efficiency of the waste gas because the incinerator is incinerated by the ultra-high temperature flame, and the energy utilization efficiency can also be improved because it can be treated with only a small amount of fuel.

In addition, there is an advantage that the specific surface area is large because of the structure having a porosity of 10 5%. Since the corrosion-resistant SiC honeycomb according to the present invention has a multi-channel structure, the contact between the gas and the honeycomb solid is excellent for realizing the excess enthalpy. Therefore, the gas requiring heat exchange has a function of allowing permeation without pressure loss.

In addition, the corrosion-resistant SiC honeycomb according to the present invention has a very small thickness of 1 mm or less as a wall forming a matrix of the honeycomb. Therefore, the gas flowing into the honeycomb passes through the partition wall without resistance, so the pressure loss is low.

In addition, the corrosion-resistant SiC honeycomb according to the present invention has a high plastic density and low porosity compared to conventional combustor materials (foam, mesh, and felt), and has excellent heat conductivity and excellent corrosion resistance against fluorine gas The efficiency of the combustor and the lifetime increase are excellent effects

Although the present invention has been described in connection with the preferred embodiments set forth above, it will be readily appreciated by those skilled in the art that various other modifications and variations can be made without departing from the spirit and scope of the invention, It is obvious that the present invention belongs to the appended claims.

1 is a front view of a conventional scrubber system for waste gas treatment.
2 is a cross-sectional view of a corrosion-resistant SiC honeycomb combustor material for incinerating refractory noxious gas according to an embodiment of the present invention.
3 is a photograph showing mixing and stirring of the silicon carbide powder, carbon powder, organic binder powder and water raw material powder of the present invention.
FIG. 4 is a photograph showing an extrusion molding process in which the powder of the present invention is molded into a mixed powder honeycomb shape mixed with each powder. FIG.
5 is a photograph showing a sintered state of the extruded SiC honeycomb of the present invention.
6 is a field emission scanning microscope (FE-SEM) photograph showing the surface of a SiC honeycomb of the present invention.
Figure 7 is an optical micrograph of the calcined SiC honeycomb (400CPSI) of the present invention.
Fig. 8 shows the corrosion resistance test results of the SiC honeycomb of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the detailed description of known functions and configurations incorporated herein will be omitted when it may unnecessarily obscure the subject matter of the present invention.

The same reference numerals are used for portions having similar functions and functions throughout the drawings. Throughout the specification, when a part is connected to another part, it includes not only a case where it is directly connected but also a case where the other part is indirectly connected with another part in between. In addition, the inclusion of an element does not exclude other elements, but may include other elements, unless specifically stated otherwise.

Hereinafter, a configuration of an energy-saving anti-corrosive SiC honeycomb combustor material 110 for incinerating refractory noxious gas included in the scrubber system 1 according to an embodiment of the present invention and a method of manufacturing the combustor material 110 Describe the method. Here, the corrosion-resistant SiC honeycomb is included in the ceramic porous body. In particular, the ceramic porous body may be SiC honeycomb.

2, the combustor material 110 for incinerating refractory noxious gas according to an embodiment of the present invention includes a combustor material 111, a waste gas inlet portion, and an oxidant inlet portion at one end, And a discharge port (150) through which the waste gas from which the waste gas is incinerated is discharged at the other end, and includes a ceramic porous body (140) and a flame side (2) at the intermediate portion.

The corrosion-resistant SiC honeycomb of the present invention has a porosity of 10 5% and includes silicon carbide. When the porosity satisfies the above-described range, there is an advantage that the room temperature thermal conductivity is excellent. The corrosion-resistant SiC honeycomb of the present invention is advantageous in that it has a large volume-specific surface area in the case of a honeycomb structure, that is, a hexagonal channel structure compared to a conventional rectangular channel. The ceramic porous body may include a honeycomb shape of 50 to 500 CPSI (Channel Per Square Inch). If the CPSI value is smaller than the CPSI value, the specific surface area of the combustor is reduced and the combustor area where the combustion reaction is maintained is small, resulting in a low combustion efficiency. If the CPSI value is larger than the CPSI value, a large resistance is generated in the flow of the gas and the combustion efficiency can be lowered.

The method of manufacturing a corrosion resistant SiC honeycomb of the present invention comprises forming a first mixture comprising silicon carbide and carbon. The carbon may be any material that contains amorphous carbon such as carbon black. It is preferable that the silicon carbide is contained in a weight ratio of 30-90% and carbon 0-15%. When the carbon content is less than the above-mentioned range, the oxide-based impurities that inhibit firing are not effectively removed. If the above range is exceeded, the melting point of carbon is extremely higher than the firing temperature of silicon carbide, and there is a possibility that porosity is increased due to difficulty in firing. The average particle diameter of the silicon carbide and the carbon black is not particularly limited as long as it is a level used in the art, but the average particle diameter of the silicon carbide is preferably 5 탆 or less, and the average particle diameter of the carbon black is preferably 10 탆 or less Do.

Further, if the first mixture is capable of mixing water and the organic binder and can maintain the honeycomb shape, the amount or type of the mixture is not particularly limited. As the organic binder, a cellulose-based organic binder may be used. Preferably, the first mixture may be 30-90 wt% silicon carbide, 0-15 wt% carbon, 5-25 wt% organic binder, and 5-30 wt% water. When the organic binder is included in the range below the above-mentioned range, the plasticity of the mixed fuel is lowered, so that the raw material may not be discharged through the mold during extrusion molding. If the above-mentioned range is exceeded, the viscosity of the mixed fuel becomes too high and sticks to the inner wall of the mold, so that extrusion molding is not smooth.

The ceramic porous body is preferably subjected to a primary drying step in which the humidity of the molded body is gradually lowered at a temperature of 50 to 100 DEG C for 100 to 170 hours in a constant temperature and humidity chamber. The ceramic porous body is preferably subjected to a second drying step of drying the molded body at a temperature of 100 to 150 DEG C for 1 to 30 hours in a high temperature drying chamber. When the drying process is completed, the molding density of the molded article becomes more homogeneous, and warping or shrinkage cracks that may occur during drying are suppressed.

In addition, the ceramic porous body is subjected to a process of burning organic substances present in the molded body by heating the molded body at a temperature of 500-700 ° C in a high temperature furnace and in an atmosphere of argon, nitrogen, or vacuum for 1-24 hours. This is a process that minimizes the influence of the organic binder during firing and excludes the variables influencing the gas atmosphere or vacuum.

The ceramic porous body is fired in the range of 1 to 10 hours under a gas atmosphere of any one of 1900 to 2000 占 폚, vacuum, argon or nitrogen in a firing furnace. The firing is preferably performed in a vacuum atmosphere.

Also, the corrosion-resistant SiC honeycomb formed from the ceramic porous body has a porosity of 10 ± 5%, b) a room temperature thermal conductivity of 80 W / m · K, and c) a corrosion resistance test using 53 wt% HF at 25 ° C. / cm ² · month or less.

The above-mentioned room temperature thermal conductivity was measured by using a coin-shaped specimen (12.6 mm ODX1.6 mmT) and using the laser flash method widely used in the world under an argon atmosphere. If the thermal conductivity of the sintered body is smaller than the above-mentioned value, it is not possible to satisfy the characteristics of the corrosion-resistant SiC honeycomb because it is characterized in that the thermal diffusivity is increased in the specimen during operation of the combustor,

The corrosion resistance test was carried out using a coin type specimen (12.6 mm OD x 1.6 mm T) and stored in a solution of 53 wt% HF at 25 ° C. Mass was measured every two weeks. For precise mass measurement, take out the specimen, clean it thoroughly, dry it in an oven at 120 ℃ for 3 hours or more, measure the mass, and put it into the hydrofluoric acid solution immediately after measurement. If the corrosion test result is higher than 0.1 mg / cm ² · month, it means that corrosion of the test specimen proceeds rapidly and it is easy to break down the sintered body. Therefore, the characteristics of the corrosion resistant SiC honeycomb can not be satisfied.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. It is to be understood that such modified embodiments are within the scope of protection of the present invention as defined by the appended claims.

1: Scrubber system
2: Flame
3: Wet tower
4: Water tank
5: Burner
110: combustor material
111: fuel inlet
112: Waste gas inlet
113: oxidant inlet
114: insulating layer
120: Premixer
130: distributor
140: Ceramic porous body
150: Outlet

Claims (11)

The combustor material 100 provided in the scrubber system for incinerating the waste gas has a fuel inflow section 111, a waste gas inflow section 112 and an oxidant inflow section 113 at one end and a waste gas is incinerated at the other end A combustor body 110 having a discharge port 150 through which exhaust gas is discharged; And a ceramic porous body combustor in which the waste gas is burned by a flame formed inside the porous ceramic body (140) provided in the combustor body,
The ceramic porous body is a) a porosity of 10 ± 5%, b) a room temperature thermal conductivity of more than 80 W / m · K, c ) in the corrosion resistance tests with the in 25 ℃ 53 Wt% HF 0.1mg / cm 2 · month Or less,
The ceramic porous body is subjected to a first drying process in which the humidity of the molded body is gradually lowered at a temperature of 50 to 100 DEG C for 100 to 170 hours in a constant temperature and humidity chamber,
Wherein the ceramic porous body includes a honeycomb shape of 300-500 CPSI (Channel Per Square Inch). The energy-saving anti-corrosive SiC honeycomb combustor material for the incineration treatment of noxious harmful gas.
The ceramic porous body according to claim 1, wherein the ceramic porous body is manufactured by mixing 30 to 90 wt% of silicon carbide, 0 to 15 wt% of carbon, 5 to 25 wt% of organic binder, and 5-30 wt% Energy-saving anti-corrosive SiC honeycomb combustor material for decomposition hazardous gas incineration treatment.
The energy-saving anti-corrosive SiC honeycomb combustor material according to claim 1, wherein the ceramic porous body is extrusion-molded.
delete The method of claim 1, wherein the ceramic porous body is subjected to a secondary drying process for drying the molded body at a temperature of 100 to 150 ° C for 1 to 30 hours in a high temperature drying chamber. Economical corrosion resistant SiC honeycomb combustor material.
The ceramic porous body according to claim 1, characterized in that the ceramic porous body is subjected to a process of burning the organic material of the molded body by heat treatment at a temperature of 500-700 ° C in a high temperature furnace and for 1 to 24 hours in an argon, Energy-saving anti-corrosive SiC honeycomb combustor material for decomposition hazardous gas incineration treatment.
The ceramic porous body according to claim 1, wherein the ceramic porous body is fired in a range of 1 to 10 hours under a gas atmosphere of any one of 1900-2200 ° C, vacuum, argon or nitrogen in a firing furnace, Energy-saving anti-corrosive SiC honeycomb combustor material for processing.
delete The fuel cell system according to claim 1, further comprising: a premixer in which fuel flowing through the fuel inlet, waste gas flowing through the waste gas inlet, and oxidant flowing through the oxidant inlet are mixed; And
And a distributor provided between the pre-mixer and the ceramic porous body combustor for uniformly introducing the gas mixed in the pre-mixer into the ceramic porous body combustor. The energy- SiC honeycomb combustor material.
The energy-saving anti-corrosive SiC honeycomb combustor material according to claim 1, further comprising a pretreatment and dust collecting device for separating and discharging impurity particles having a specific particle size or more contained in the waste gas.
The energy-saving anti-corrosive SiC honeycomb combustor material according to claim 1, further comprising a concentrator for concentrating the waste gas to separate and remove a part of the inert gas contained in the waste gas.

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