JP2008039280A - Flame retardant decomposition burner - Google Patents

Abstract

A silane-based material that generates powder (SiO ₂ or the like) by combustion decomposition, such as SiH ₄ , Si ₂ H ₆ , TEOS, or SiF ₄ , and a fluorocarbon-based difficulty such as CF ₄ , SF ₆ , or NF _3. Flame-retardant material decomposition that can be detoxified with high combustion decomposition efficiency for process exhaust gas containing flammable materials and can continue operation for a long time without reducing the processing efficiency Provide a burner.
SOLUTION: A plurality of combustion burners 50 for forming a flame in a combustion cylinder and a process exhaust gas containing a flame-retardant substance are introduced into a peripheral side wall of the combustion cylinder 2 with one end closed. A plurality of process exhaust gas introduction ports 60 are attached. Each combustion burner 50 is attached with its axis L1 inclined to the downstream side so that each jet flame f can converge at substantially the same point P1a on the center axis L of the combustion cylinder 2, and each process exhaust gas introduction port 60 has its The extension of the axis L2 is attached by inclining the axis L2 to the downstream side so that the extension line of the axis L2 intersects at substantially the same point on the central axis L of the combustion cylinder 2 at the point P2 upstream from the convergence region of the ejection flame f.
[Selection] Figure 2

Description

TECHNICAL FIELD The present invention relates to a flame retardant decomposition burner, and in particular, a silane that is a film forming raw material contained in a process exhaust gas discharged in a semiconductor manufacturing process, a liquid crystal manufacturing process, a solar cell manufacturing process, a gas processing process in a waste transformer, or the like. Substances (SiH ₄ , Si ₂ H ₆ , TEOS (Si (OC ₂ H ₅ ) ₄ ), SiF _4, etc.) and Freon-based hardly decomposable substances (CF ₄ , SF ₆ , C used in cleaning or etching) ₂ F ₆ , C ₃ F ₈ , C ₄ F ₈ , CHF ₃ , NF _{3 and the} like).

  Many kinds of harmful substances are contained in process exhaust gas discharged from a semiconductor manufacturing process, a liquid crystal manufacturing process, a solar cell manufacturing process, a gas processing process in a waste transformer, or the like. Various exhaust gas treatment apparatuses have been proposed to detoxify such harmful substances and release them into the atmosphere.

  For example, Patent Document 1 describes an exhaust gas abatement apparatus for the purpose of effective combustion decomposition treatment of process exhaust gas containing a flame retardant substance, in which combustion extending vertically with the upper end closed is described. On the peripheral side wall of the cylindrical body, the process exhaust gas introduction port is arranged on the upstream side so that its axial center is parallel to the plane perpendicular to the central axis of the combustion cylindrical body, and a plurality of combustion burners on the downstream side Is disposed in a direction that is inclined with respect to a plane perpendicular to the central axis of the combustion cylinder and coincides with a tangent to a virtual circle assumed for the combustion cylinder, thereby increasing the heat of the process exhaust gas. The residence time in a wide combustion area is lengthened to promote and decompose the thermal decomposition of process exhaust gas containing flame retardant substances.

  In Patent Document 2, as shown in a plan view in FIG. 5a and a cross-sectional view in FIG. 5b, the upper end of the combustion cylinder 2 is closed by a closing wall 3, and the closing wall 3 contains a flame retardant. A process exhaust gas introduction port 40 for ejecting process exhaust gas is attached so as to coincide with the central axis L of the combustion cylinder 2, and a plurality of combustion burners 50 are attached at positions concentrically from the central axis L, Each of the combustion burners 50 is provided with a flame retardant substance decomposition burner 10 that is attached with its axis inclined to the downstream side so that each jet flame f can converge at substantially the same point on the central axis L of the combustion cylinder 2. Are listed.

In this flame-retardant material decomposition burner 10, the flames f from the plurality of combustion burners 50 converge at substantially the same point on the central axis L of the combustion cylinder 2, so that a high temperature is generated in the region where the flame has converged. A combustion region S is formed. Since the process exhaust gas from the process exhaust gas introduction port 40 surely passes through the region S, the combustion decomposition treatment of the flame retardant substance in the exhaust gas proceeds effectively, and the CF ₄ having a high combustion decomposition temperature or Even with SF ₆ , a high decomposition rate can be obtained.
JP 2001-165422 A JP 2003-202108 A

For example, the present inventors have continuously conducted an experiment in which a process exhaust gas discharged from a semiconductor manufacturing process is subjected to a combustion decomposition process using a flame retardant substance decomposition burner described in Patent Document 2. In this process, the flame retardant decomposition burner has a configuration in which a process exhaust gas introduction port 40 for ejecting process exhaust gas containing a flame retardant material and a plurality of combustion burners 50 are attached to the closed wall 3 at the upper part of the combustion chamber. For this reason, both of them must be positioned close to each other, and the introduced process exhaust gas is immediately treated at a high temperature to increase the efficiency of detoxification. On the other hand, the process exhaust gas to be detoxified is SiH ₄ , Si _2. when containing a large amount of silane-based material, such as _{H 6, TEOS (Si (OC} 2 H 5) 4) and SiF _4, in the vicinity of the combustion burner 50, as a combustion product, the SiO ₂ powder (Siri Powder) has experienced that are easily formed. Such powder formation tends to adhere and accumulate on the combustion cylinder and the tip of the burner, and may cause clogging of the process exhaust gas introduction port 40 and the combustion burner 50. When powder clogging or the like occurs, the supply of fuel from the combustion burner 50 is hindered and the combustion state is deteriorated. In the worst case, there is a risk of misfire, so this must be avoided. It is also conceivable that powder as a combustion product is formed and agglomerated in the process exhaust gas introduction port 40.

The amount of process gas used in the semiconductor manufacturing process or the liquid crystal manufacturing process is substantially proportional to the size of the substrate. In recent years, in the semiconductor manufacturing field, the wafer size is shifting from 200 mm to 300 mm, and in the liquid crystal manufacturing field, the substrate glass size is shifting from the fifth generation to the sixth generation, and from the sixth generation to the seventh generation. . Along with this, the amount of process gas used has increased remarkably, and naturally the amount of silane-based substances used has increased, and the amount of SiO ₂ powder (silica powder) discharged has increased as a combustion product. Yes. Therefore, it is a big problem in the flame-retardant substance decomposition burner to effectively avoid the occurrence of the trouble due to the above-mentioned SiO ₂ powder (silica powder).

  In addition, when the amount of process exhaust gas to be processed increases, the present inventors increase the flow rate of process exhaust gas fed from one process exhaust gas introduction port 40 into the combustion chamber, and the process exhaust gas pushes the converged flame. We also experienced a decrease in combustion cracking efficiency because it opened and passed.

In the exhaust gas abatement apparatus described in Patent Document 1, a combustion burner is arranged on the peripheral side wall of the combustion cylinder, and to some extent, combustion products such as SiO ₂ are scattered and enter the combustion burner. Can be suppressed. In addition, since the process exhaust gas introduction port is arranged on the upstream side and the combustion burner is arranged on the downstream side, a sufficient distance between the process exhaust gas introduction port and the combustion flame can be secured. Since the vicinity of the introduction port can be set as a low temperature region, it is expected that combustion products are generated to some extent in and near the process exhaust gas introduction port.

However, in the exhaust gas abatement apparatus having the shape described in Patent Document 1, the process exhaust gas introduction port is arranged in a direction parallel to a plane orthogonal to the central axis of the combustion cylinder, and the process exhaust gas is SiO 2. _When powder such as ₂ is included from the beginning, or when combustion products are generated in the process exhaust gas introduction port, it stays in the port and agglomerates, and the factor that hinders the flow of process exhaust gas There is a fear. As described above, in a situation where the amount of process gas to be used tends to increase remarkably, powders such as SiO ₂ are often included in the discharged process exhaust gas from the beginning. The body can stay sufficiently in the process exhaust gas introduction port.

  Furthermore, as described in Patent Document 2, the process exhaust gas introduction port is placed on a surface orthogonal to the central axis of the combustion cylinder as compared with the case where the process exhaust gas introduction port is attached in a direction coinciding with the central axis of the combustion cylinder. When arranged in parallel directions, the combustion cracking efficiency is reduced because the shape of the combustion flame is disturbed and the generation of the high temperature region is limited.

Furthermore, in the exhaust gas abatement apparatus having the shape described in Patent Document 1, the direction in which the burner flame is ejected is in a direction that coincides with the tangent of the virtual circle assumed for the combustion cylinder, and there is a region where a plurality of flames converge at one place. Since it does not exist, it is difficult to form a sufficiently high-temperature combustion decomposition treatment region, and sufficient treatment efficiency cannot be obtained for process exhaust gas containing chlorofluorocarbon-based flame retardants such as CF ₄ , SF ₆ , and NF ₃ .

The present invention has been made in view of the above circumstances, and is a silane-based material that generates powder (SiO ₂ or the like) by combustion decomposition, such as SiH ₄ , Si ₂ H ₆ , TEOS, SiF _4, and the like. High combustion decomposition treatment efficiency can be secured even for process exhaust gas containing chlorofluorocarbon-based flame retardants such as CF ₄ , SF ₆ , and NF ₃ , and the operation is continued without lowering the treatment efficiency. It is an object of the present invention to provide a further improved flame retardant decomposition burner that is possible.

  A flame retardant decomposition burner according to the present invention includes a combustion cylinder whose one end is closed, a plurality of combustion burners for forming a flame in the combustion cylinder, and a process exhaust gas containing the flame retardant in the combustion cylinder. Each combustion burner and each process exhaust gas introduction port is a flame retardant substance decomposition burner attached to the peripheral side wall of the combustion cylinder, Each of the combustion burners is attached to the peripheral side wall of the combustion cylinder with the axis inclined to the downstream side so that the respective jet flames can converge at substantially the same point on the central axis of the combustion cylinder. The process exhaust gas introduction port has a combustion cylinder whose axis is inclined downstream so that the extension of the axis intersects at substantially the same point on the central axis of the combustion cylinder upstream of the convergence region of the jet flame Characterized in that attached to the peripheral side wall.

  In the flame-retardant material decomposition burner according to the present invention, the combustion burner and the process exhaust gas introduction port are both attached to the peripheral side wall of the combustion cylinder, and the flame retardant is in the form of being attached to the upper closed wall of the combustion cylinder. Compared to the burner for burned substance, the degree of clogging of the port or burner is less due to the powder as the combustion product.

  Further, the plurality of process exhaust gas introduction ports are inclined at the downstream side so that the extended line of the axial line intersects at substantially the same point on the central axis of the combustion cylinder upstream from the convergence region of the ejection flame. Since it is attached to the peripheral side wall of the combustion cylinder, the process exhaust gas introduction port is arranged in such a manner that its axial center is in a direction parallel to a plane orthogonal to the central axis of the combustion cylinder. As compared with, it is possible to effectively prevent the generated powder from staying in the port and agglomerating. This structure also makes it possible to secure the required distance between the flame and the process exhaust gas introduction port outlet, and it is effective to generate combustion products (silica powder, etc.) near the outlet of the process exhaust gas introduction port. Can be prevented. Accordingly, it is possible to effectively prevent the process exhaust gas introduction port and the burner from causing a channel failure due to powder.

  Furthermore, since the process exhaust gas introduction port is attached to the peripheral side wall of the combustion cylinder with its axis inclined to the downstream side, the cross-sectional area at the port outlet increases in an elliptical shape according to the angle of inclination, and as a result The process exhaust gas can be smoothly introduced into the combustion cylinder by gradually reducing the gas flow rate. Therefore, the influence on the combustion flame shape change can be reduced.

  In order to further increase this effect, the process exhaust gas introduction port may be configured to have a portion whose cross-sectional area gradually increases toward the outlet portion into the combustion cylinder. As a result, it is possible to more effectively prevent the process exhaust gas introduction port from causing a flow path failure due to powder.

In the flame-retardant material decomposition burner according to the present invention, the plurality of combustion burners are inclined with respect to the downstream side so that the respective jet flames can converge at substantially the same point on the central axis of the combustion cylinder, as described above. Is attached to the peripheral side wall of the combustion cylinder, and a high-temperature combustion region is formed around the region where the flame has converged. In addition, since the process exhaust gas is introduced into the combustion cylinder from a plurality of process exhaust gas introduction ports, the process exhaust gas can enter the high temperature combustion region from above without increasing the flow velocity. As a result, combustion decomposition of silane-based materials such as SiH ₄ , Si ₂ H ₆ , TEOS, and SiF ₄ mixed with process exhaust gas and Freon-based flame retardant materials such as CF ₄ , SF ₆ , and NF ₃ proceeds with high efficiency. To do. Further, since the plurality of process exhaust gas introduction ports are arranged with the axis inclined to the downstream side so as to intersect at substantially the same point on the central axis of the combustion cylinder, as described above, without increasing the initial speed. In addition, it is possible to enter the combustion flame without causing great disturbance, and also from this point, high combustion decomposition efficiency of the process exhaust gas containing the fluorocarbon flame retardant can be obtained. In addition, it is possible to eliminate the phenomenon that the process exhaust gas flows down along the wall surface region of the combustion cylinder, that is, through the low temperature region of the combustion chamber. This also prevents a decrease in combustion decomposition efficiency. .

In the flame-retardant substance decomposition burner according to the present invention, the inclination angle of the axis of each combustion burner and each process exhaust gas introduction port is preferably in the range of 15 to 60 degrees with respect to the central axis of the combustion cylinder. In the experiments by the present inventors, the inclination angle of the axis of each combustion burner is preferably around 30 degrees, and the inclination angle of the axis of each process exhaust gas introduction port is preferably around 45 degrees. By selecting the angle in this way, higher combustion decomposition efficiency could be obtained. If the inclination angle of the combustion burner is larger than 60 degrees, it is not preferable because the vicinity of the process exhaust gas introduction port is heated to promote the generation of SiO _{2. If} the inclination angle is smaller than 15 degrees, the flame approaches the inner surface of the combustion cylinder. This is not preferable because thermal damage of the combustion cylinder easily proceeds. Further, if the inclination angle of the axis of each process exhaust gas introduction port is smaller than about 15 degrees, the space above the flame becomes too large, and the flame-retardant material decomposition burner becomes unnecessarily long. On the other hand, if it exceeds 60 degrees, the process exhaust gas entering from each process exhaust gas introduction port forms a turbulent flow, which is not preferable.

  In the flame-retardant material decomposition burner according to the present invention, each combustion burner is preferably detachable from the combustion casing in order to facilitate maintenance. As a method for making the combustion burner detachable, for example, a means for attaching a sheath tube portion on the combustion housing side and inserting the combustion burner main body into it and attaching it with a joint that can be attached and detached without using a tool such as a clamp-type joint can be considered. .

The flame retardant substance decomposition burner according to the present invention preferably further includes a scraper that rotates along the inner wall surface of the combustion cylinder. As a result, when SiO ₂ (silica powder) is generated from the silane-based material by combustion decomposition, the powder as the combustion product adhering to the inner surface of the combustion cylinder can be scraped off, and the flame-retardant material decomposition It is possible to prevent the burner from degrading. In the flame retardant substance decomposition burner according to the present invention, a scraper can be easily attached using a lid member that closes the upper end side of the combustion cylinder, and the lid member is on the structure of the flame retardant substance decomposition burner. Further, since it is located away from the combustion flame, it is possible to effectively avoid damage to the drive mechanism of the scraper due to heat. Moreover, the weight of the lid member can be reduced, and it is easy to repair the inside of the combustion cylinder by opening the lid member during maintenance.

  In the flame-retardant substance decomposition burner according to the present invention, preferably, an inner cylinder made of a heat-resistant metal is provided along the inner wall of the combustion cylinder, and the scraper rotates along the inner wall surface of the inner cylinder. To be done. By providing an inner cylinder made of such a heat-resistant metal, it is possible to avoid thermal damage to the inner wall surface of the combustion cylinder that is usually made of an irregular refractory material commonly called refractory brick or castable. In addition, the life of the flame retardant decomposition burner can be extended. In addition, when the inner cylinder made of a heat-resistant metal is damaged by heat or the like, it can be used again as a flame-retardant substance decomposition burner by replacing only the inner cylinder. The material of the inner cylinder is preferably a heat resistant metal such as SUS310S or Inconel, or a ceramic such as silicon nitride or silicon carbide.

  The flame retardant substance decomposition burner according to the present invention includes a plurality of process exhaust gas introduction ports, and includes a plurality of manufacturing or processing apparatuses installed in parallel or a single unit having a plurality of chambers. Even if the process exhaust gas discharged at the same time is processed at the same time, the process exhaust gas can be joined upstream from the combustion cylinder by installing as many process exhaust gas introduction ports as the number of manufacturing or treatment equipment or chambers. Therefore, the danger due to mixing of the process exhaust gas can be eliminated.

In the flame retardant decomposition burner according to the present invention, the process exhaust gas to be processed is not particularly limited, but the process exhaust gas is discharged from a semiconductor manufacturing process, a liquid crystal manufacturing process, a solar cell manufacturing process, or a gas processing process in a waste transformer. In the case of a process exhaust gas containing a chlorofluorocarbon flame retardant material such as CF ₄ , SF ₆ and NF ₃ together with a silane material such as SiH ₄ , Si ₂ H ₆ , TEOS and SiF _4. The flame retardant decomposition burner works particularly effectively.

According to the flame retardant decomposition burner according to the present invention, SiH ₄ , Si ₂ H ₆ , TEOS, SiF discharged in a semiconductor manufacturing process, a liquid crystal manufacturing process, a solar cell manufacturing process, a gas processing process in a waste transformer, or the like. ₄ relative to the combustion decomposed by the powder process exhaust gas containing CFC-based flame retardant materials such as _{CF 4,} SF 6, NF ₃ at the same time as the silane-based material to produce a (SiO _2, etc.), such as, high combustion decomposition It becomes possible to perform the detoxification process with efficiency. In addition, it is possible to continue operation for a long time without lowering the processing efficiency.

  Hereinafter, an embodiment of the flame retardant substance decomposition burner according to the present invention will be described with reference to the drawings. FIG. 1 shows an example of a flame retardant substance decomposition burner 1, FIG. 1 a is a plan view, and FIG. 1 b is a cross-sectional view taken along line bb in FIG. FIG. 2 schematically illustrates flame formation and process exhaust gas introduction position in the flame retardant material decomposition burner according to the present invention.

  The burner 1 includes a cylindrical combustion cylinder 2 and a lid member 3 that closes one end of the combustion cylinder 2. In this example, the combustion cylinder 2 includes a cylinder main body 21 made of an irregular refractory material, an outer cylinder 22 made of a heat-resistant metal covering the outside, and an inner made of a heat-resistant metal such as SUS310S or Inconel. The cylinder 23 is constituted. The inner cylinder 23 is disposed along the inner wall of the cylinder main body 21, and preferably a slight gap 24 is formed between the inner cylinder 23 and the inner wall surface of the cylinder main body 21. Preferably, the inner cylinder 23 is attached to the cylinder body 21 by an appropriate means in a state where it can be easily detached from the cylinder body 21. The lower open end of the combustion cylinder 2 is connected to a suction blower or a water scrubber or the like via an appropriate pipe line as in the conventional burner of this type.

  An appropriate inner flange 25 is formed at the upper end of the combustion cylinder 2, and the lid member 3 is detachably attached thereto by means such as a set bolt 31. A through hole 32 is formed in the center of the lid member 3 and is used for maintenance or for attaching a scraper 70 described later. Usually, it is sealed with a cap 33.

  A plurality of combustion burners 50 are detachably attached to the combustion cylinder 2 at equal intervals. In the example shown in the figure, three combustion burners 50 are attached at intervals of 120 degrees, but two or more are optional. Each combustion burner 50 has a predetermined angle α (preferably in the range of 15 to 50 degrees, more preferably, so that the extension line of the axis L1 intersects at substantially the same point P1 on the center axis L of the combustion cylinder 2. Is inclined downward at 30 degrees), so that each ejection flame f converges at substantially the same point P1a on the central axis L of the combustion cylinder 2 as shown in FIG. Become. A high-temperature combustion region S is formed around the region where the flame f has converged.

  In the combustion cylinder 2, a plurality of process exhaust gas introduction ports 60 are further formed at equal intervals. In the illustrated example, the three process exhaust gas introduction ports 60 are attached at intervals of 120 degrees so as to be at intermediate positions between the combustion burners 50, respectively. Each process exhaust gas introduction port 60 has its extension line of the axis L2 intersecting at substantially the same point on the central axis L of the combustion cylinder 2 at the position P2 upstream from the convergence region of the jet flame f described above. It is formed to be inclined at a predetermined angle β (preferably in the range of 15 to 50 degrees, more preferably 45 degrees) on the downstream side. Process exhaust gas from, for example, a semiconductor manufacturing apparatus or the like is introduced into the process exhaust gas introduction port 60 via a pipe 61.

  During the combustion treatment of the process exhaust gas, the process exhaust gas G is introduced into the combustion cylinder 2 from each process exhaust gas introduction port 60 in a state where the combustion flame f is formed in each combustion burner 50. Since each process exhaust gas introduction port 60 is inclined downward at an angle β, even if powder such as SiO 2 is contained in the process exhaust gas G, the powder is in the pipe 61 and the process exhaust gas introduction port 60. Without entering the combustion cylinder 2.

Since the process exhaust gas G is ejected from each process exhaust gas introduction port 60 so as to intersect at substantially the same point on the central axis L of the combustion cylinder 2 in a posture inclined to the downstream side, the combustion cylinder does not cause a large turbulent flow. 2 centered on the central axis L. The merged process exhaust gas G enters from the upper side toward the high-temperature combustion region S formed in the region where the flame f converges. Thereby, combustion decomposition of silane-based materials such as SiH ₄ , Si ₂ H ₆ , TEOS, SiF ₄ and CFC-based flame retardant materials such as CF ₄ , SF ₆ , and NF ₃ mixed in the process exhaust gas G is highly efficient. proceed. The process exhaust gas G that has been subjected to the combustion decomposition process flows out from the lower end of the combustion cylinder 2.

In the process of combustion decomposition, a powder material such as SiO ₂ is generated. The production of the combustion products occurs mainly downstream of the process exhaust gas introduction port 60, and the process exhaust gas introduction port 60 is in a low temperature region away from the formed flame f to the upstream side. A situation in which SiO ₂ or the like becomes a block and blocks the process exhaust gas introduction port 60 does not occur. In addition, since the process exhaust gas G that has joined the central portion of the formed flame f enters, and the process exhaust gas G and the formed flame f are ejected downward, the generated powder material such as SiO ₂ is positive. In addition, it is possible to avoid a situation where energy is given to the downstream side and SiO _{2 and the} like generated in the vicinity of the outlet of each combustion burner 50 accumulate in a lump and block the outlet. Therefore, for a long time, the process exhaust gas G containing a silane-based material such as SiH ₄ , Si ₂ H ₆ , TEOS, SiF ₄ and a chlorofluorocarbon-based flame retardant material such as CF ₄ , SF ₆ , NF ₃ is highly burned and decomposed. It becomes possible to perform the detoxification process with efficiency.

  FIG. 3 is a view corresponding to FIG. 1 b showing another embodiment of the flame retardant substance decomposition burner according to the present invention. This flame retardant substance decomposition burner 1a is different from the flame retardant substance decomposition burner 1 shown in FIG. Other configurations are the same, and are denoted by the same reference numerals. The scraper 70 is made of a heat-resistant alloy such as SUS310S or Inconel, or a ceramic such as silicon nitride or silicon carbide, and includes a shaft portion 71 that passes through the through hole 32 formed in the center of the lid member 3, and the shaft portion 71. And a scraping rod 72 that moves along the inner wall surface of the inner cylinder 23 attached to the inner wall of the combustion cylinder 2. The shaft portion 71 includes a handle 73 in the illustrated example. By operating the handle 73, the scraping bar 72 can be periodically rotated along the inner wall surface of the inner cylinder 23. Thereby, the powder adhering to the inner cylinder 23 is effectively scraped off. The scraping bar 72 can be periodically rotated by driving the motor.

  FIG. 4 shows another embodiment of the flame-retardant material decomposition burner according to the present invention, FIG. 4a is a view corresponding to FIG. 1b, and FIG. 4b is a cross-sectional view taken along the line bb of FIG. . This flame retardant substance decomposition burner 1b has a portion 61 in which the cross-sectional area of the process exhaust gas introduction port 60 gradually expands toward the outlet part into the combustion cylinder 2, so that the flame retardant substance shown in FIG. It differs from the decomposition burner 1. Other configurations are the same, and are denoted by the same reference numerals. In this example, the portion of the through hole formed in the cylinder main body 21 in the process exhaust gas introduction port 60 is a portion 61 that gradually expands in a trumpet shape. With this configuration, it is possible to smoothly reduce the gas flow rate and smoothly introduce the process exhaust gas into the combustion cylinder 2, and further reduce the influence of the process exhaust gas on the shape change of the combustion flame f. Can do. Further, it is possible to more effectively prevent the process exhaust gas introduction port 60 from causing a channel failure due to powder.

  In the flame-retardant material decomposition burner 1, 1 a according to the present invention, the vicinity of the lid member 3 is away from the combustion burner 50, so that the temperature is relatively low. Therefore, the configuration of the lid member 3 can be simplified and reduced in weight. Therefore, an effect of facilitating work when opening the lid member 3 and maintaining the combustion cylinder is also brought about.

1 shows one embodiment of a flame retardant substance decomposition burner according to the present invention, FIG. 1a is a plan view, and FIG. 1b is a sectional view taken along line bb of FIG. The figure which shows typically the entering state of the process exhaust gas with respect to the ejection flame in the flame-retardant substance decomposition burner by this invention. The figure equivalent to FIG. 1 b which shows the other form of the flame-retardant material decomposition | disassembly burner by this invention. It is a figure which shows the further another form of the flame-retardant substance decomposition | disassembly burner by this invention, FIG. 4a is a figure equivalent to FIG. 1b, FIG. 4b is sectional drawing by the bb line of FIG. It is a figure which shows the conventional flame retardant substance decomposition burner, FIG. 5a is a top view, FIG. 5b is sectional drawing by the bb line of FIG. 5a.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a ... Flame-retardant material decomposition burner, 2 ... Cylindrical combustion cylinder, 21 ... Cylinder main body which consists of an indefinite form refractory material, 22 ... Outer cylinder made from a heat-resistant metal, 23 ... Made from a heat-resistant metal Inner cylinder, 3 ... lid member, 32 ... through hole, L ... center axis of combustion cylinder, 50 ... combustion burner, L1 ... axis of combustion burner, α ... inclination angle of axis of combustion burner, f ... flame, S ... High temperature region of flame, 60 ... process exhaust gas introduction port, L2 ... axis of process exhaust gas introduction port, β ... inclination angle of axis of process exhaust gas introduction port, 70 ... scraper

Claims (6)

A combustion cylinder having one end closed; a plurality of combustion burners for forming a flame in the combustion cylinder; a plurality of process exhaust gas introduction ports for introducing process exhaust gas containing a flame retardant into the combustion cylinder; And each combustion burner and each process exhaust gas introduction port are flame retardant substance decomposition burners attached to the peripheral side wall of the combustion cylinder,
The plurality of combustion burners are attached to the peripheral side wall of the combustion cylinder with the axis inclined to the downstream side so that the respective jet flames can converge at substantially the same point on the central axis of the combustion cylinder. Each of the process exhaust gas introduction ports has an axis inclined to the downstream side so that the extension of the axis intersects at substantially the same point on the central axis of the combustion cylinder upstream from the convergence region of the jet flame. A flame-retardant substance decomposition burner, characterized in that it is attached to the peripheral side wall.   2. The flame retardant substance decomposition burner according to claim 1, wherein the process exhaust gas introduction port has a portion whose cross-sectional area gradually increases toward an outlet portion into the combustion cylinder.   The flame retardancy according to claim 1 or 2, wherein the inclination angle of the axis of each combustion burner and each process exhaust gas introduction port is in the range of 15 to 60 degrees with respect to the central axis of the combustion cylinder. Material decomposition burner.   The flame retardant substance decomposition burner according to any one of claims 1 to 3, further comprising a scraper that rotates along an inner wall surface of the combustion cylinder.   The flame retardant according to claim 4, wherein the combustion cylinder includes an inner cylinder made of a heat resistant metal along the inner wall, and the scraper rotates along the inner wall surface of the inner cylinder. Material decomposition burner. Process exhaust gas to be treated is powdered by combustion decomposition such as SiH ₄ , Si ₂ H ₆ , TEOS, SiF ₄ discharged from a semiconductor manufacturing process, a liquid crystal manufacturing process, a solar cell manufacturing process, or a gas processing process in a waste transformer. Process flue gas containing silane-based materials that produce a body, and chlorofluorocarbon-based flame retardant materials such as CF ₄ , SF ₆ , C ₂ F ₆ , C ₃ F ₈ , C ₄ F ₈ , CHF ₃ , and NF ₃ The flame retardant substance burner according to any one of claims 1 to 5, which is a process exhaust gas.

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