JPH10122539A - Discharged gas processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a continuous harm removal operation even in the case that a gas discharging device is stopped in its operation, provide a low cost device as well as a low cost operation and further adapted for an improvement of a existing facility by a method wherein there is provided a harm removing device different from a combustion type gas-discharging device and at the same time there is provided a change-over valve for changing-over discharged gas passages in both devices. SOLUTION: A combustion type discharged gas processing device A is provided with a discharged gas feeding passage 11 fro feeding discharged gas discharged from a semiconductor manufacturing device. Then, the discharged gas feeding passage 11 is provided with a branch passage 23 connected to a harm-removing cylinder B acting as a harm-removing processing device and concurrently an inlet section of the combustion type discharged gas processing device A and the branch passage of the branch passage 23 are provided with changing-over valves 24, 25 for use in changing-over the discharged gas passages. The harm-removing cylinder B is filled with dry harm-removing agent such as copper (II) hydroxide or copper oxide or the like and the discharge gas processed at the harm-removing cylinder B is discharged out of a gas discharging passage 26 connected to the processed gas discharging passage 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas treatment apparatus and, more particularly, to an exhaust gas treatment apparatus provided with a combustion type exhaust gas treatment apparatus, which is used for abnormal operation or maintenance work of the combustion type exhaust gas treatment apparatus. The present invention relates to an exhaust gas treatment device capable of continuously performing an exhaust gas removal treatment even when the operation of the apparatus is stopped.

[0002]

2. Description of the Related Art For example, since a gas containing flammable or combustible harmful components is discharged as an exhaust gas from a device for manufacturing semiconductors and LCDs, a harmless (harmless) treatment of these harmful components is performed. It is necessary to discharge exhaust gas after going.
As one of the devices for performing such an exhaust gas removal treatment, a combustion-type exhaust gas treatment device is known.

[0003] The combustion type exhaust gas treatment apparatus performs an abatement process by burning or decomposing various harmful components contained in the exhaust gas. The exhaust gas and the supporting gas are burned by a combustion burner. It has a structure in which it is ejected into the room and burned.

[0004]

However, in the above combustion type exhaust gas treatment apparatus, abnormal flow rates of air and the like necessary for combustion, abnormalities of various utilities such as cooling water, overheating of the apparatus, and exhaust of combustion gas (process gas). When an operation abnormality such as a vacuum pump abnormality occurs, the abatement operation must be stopped immediately.However, when the operation of the combustion type exhaust gas treatment device is stopped, the semiconductor manufacturing The operation of the equipment must also be stopped.

[0005] Usually, the above-mentioned operation abnormality occurs in an unexpected state, so that the combustion-type exhaust gas treatment apparatus and the semiconductor manufacturing apparatus and the like are urgently stopped simultaneously with the occurrence of the operation abnormality. However, when the semiconductor manufacturing equipment is stopped in an emergency, the film forming operation of the wafer being manufactured is stopped halfway, and such a wafer being formed cannot be formed again. Must be disposed of.

Further, in the combustion type exhaust gas treatment apparatus, since solid oxides generated when harmful components are burned during the operation adhere to the inner wall of the combustion chamber, the operation of the apparatus is temporarily stopped, and (Solid oxide) is removed, but it is necessary to stop the operation of the semiconductor manufacturing apparatus and the like during the operation of removing the deposits.

In view of the above, it is conceivable to install a plurality of combustion type exhaust gas treatment devices in parallel and perform a switching operation so that the exhaust gas can be continuously treated for detoxification. In addition to the point, the piping becomes complicated and the installation space becomes large, so that it is not practical.

Therefore, the present invention can continuously perform the exhaust gas elimination processing even when the operation of the combustion type exhaust gas treatment apparatus is temporarily stopped, and there is no need to stop the operation of the semiconductor manufacturing apparatus and the like. In addition, an object of the present invention is to provide an exhaust gas treatment apparatus which can be implemented with a simple apparatus configuration, has low apparatus costs and operation costs, and can cope with the improvement of existing facilities.

[0009]

In order to achieve the above object, an exhaust gas treatment apparatus according to the present invention is an exhaust gas treatment apparatus provided with a combustion type exhaust gas treatment apparatus that burns and removes harmful components in exhaust gas. A branch path is provided in an exhaust gas introduction path for introducing exhaust gas into a combustion type exhaust gas treatment apparatus, and abatement means different from the combustion type exhaust gas treatment apparatus is provided in the branch path, and the combustion type exhaust gas treatment apparatus and the branch path are provided. A switching valve for switching an exhaust gas path to the abatement means.

Further, the present invention is characterized in that the abatement means provided in the branch path is an abatement cylinder filled with an abatement agent which removes harmful components in exhaust gas by adsorption or the like. Further, a purge gas introduction path is provided for discharging the exhaust gas remaining in the combustion type exhaust gas treatment apparatus toward the abatement processing means provided in the branch path.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a system diagram showing an example of an exhaust gas treatment apparatus of the present invention. This exhaust gas treatment apparatus has a combustion type exhaust gas treatment apparatus A and an abatement cylinder at an end of an exhaust gas system discharged from a semiconductor manufacturing apparatus or the like. B is installed in parallel.

The combustion type exhaust gas treatment apparatus A has an exhaust gas introduction path 11 for introducing exhaust gas discharged from a semiconductor manufacturing apparatus or the like, and a processing gas exhaust path for exhausting the processing gas which has been treated by the combustion type exhaust gas treatment apparatus A. The exhaust gas containing harmful components is supplied from the exhaust gas introduction path 11 to the combustion burner 13 and subjected to the combustion detoxification treatment.
It is discharged from the processing gas exhaust path 12.

The combustion burner 13 has an exhaust gas passage 13a to which exhaust gas is supplied, a lift gas passage 13b to which nitrogen gas is supplied, and a primary air passage 13c to which air for harmful component combustion is supplied. It has a five-tube structure in which a secondary air flow path 13d to which air for auxiliary fuel combustion is supplied and a fuel flow path 13e to which auxiliary fuel such as LPG is supplied are provided. Combustion chamber 1
Reference numeral 4 denotes a double wall structure including an inner wall 14a formed of a porous material and an outer wall 14b formed of a normal metal material or the like.

Further, a pilot burner 15 for ignition and a spray nozzle 1 for removing deposits are provided in the combustion chamber 14.
6 and a gas nozzle 17 for introducing a pressurized gas into a space formed between the inner wall 14a and the outer wall 14b. An exhaust chamber 19 having a cooling water nozzle 18 for cooling the combustion gas is provided below the combustion chamber 14. A water-sealed vacuum pump 20 and a gas-liquid separator 21 are provided in the exhaust chamber 19. The processing gas exhaust path 12 provided and a purge gas introduction path 22 for discharging gas in the combustion type exhaust gas treatment apparatus A are provided.

The exhaust gas introduction path 11 is provided with a branch path 23 connected to the abatement cylinder B. Exhaust gas is provided between the inlet of the combustion type exhaust gas treatment apparatus A and the branch of the branch path 23. Switching valve 2 for switching the path
4, 25 are provided respectively.

The abatement cylinder B provided in the branch path 23 has a dry abatement agent that adsorbs harmful components in exhaust gas or detoxifies it by a chemical reaction, such as cupric hydroxide or the like. Exhaust gas which is filled with an abatement agent containing copper oxide or the like as a main component and is abated by the abatement cylinder B is exhausted from an exhaust path 26 connected to the processing gas exhaust path 12.

First, in a normal operation state, the switching valve 24 at the inlet of the combustion type exhaust gas treatment apparatus A is opened, the switching valve 25 of the branch path 23 is closed, the spray nozzle 16 for removing attached matter is closed, and the cooling water nozzle is opened. 18, the valve 18a of the purge gas introduction path 22 is closed, and the flow paths 13a, 13b, 13c, 13d, 13e of the combustion burner 13 are provided with:
Exhaust gas, nitrogen gas, air for combustion of harmful components, air for combustion of auxiliary fuel, LPG, etc. are respectively supplied to the pilot burner 15. Fuel and air such as LPG are supplied to the pilot burner 15 from the passages 15 a, 15 b, respectively. A flame is formed, and compressed air or the like is introduced from the gas nozzle 17.

From the exhaust gas introduction path 11 to the combustion burner 13
Components in the exhaust gas supplied to the combustion burner 13
The solid oxide generated during combustion is detoxified by burning in a combustion flame or by thermal decomposition, and its adhesion to the inner wall surface is suppressed by compressed air ejected through the porous material of the inner wall 14a. , Together with the combustion gas. The combustion gas cooled by the cooling water ejected from the cooling water nozzle 18 is sucked by the vacuum pump 20 together with the solid oxide and the cooling water, separated from the cooling water and the like by the gas-liquid separator 21, and discharged from the processing gas exhaust passage 12. Exhausted. On the other hand, the solid oxide suspended in the cooling water by the stirring action of the vacuum pump 20 is extracted from the gas-liquid separator 21 along with the cooling water to the path 21a,
Post-processing such as solid-liquid separation is performed.

As described above, in the exhaust gas treatment apparatus shown in this embodiment, in the normal operation state, the exhaust gas elimination processing is performed only by the combustion elimination processing in the combustion type exhaust gas treatment apparatus A.

When removing the solid oxide adhering to the inside of the combustion chamber 14, the switching valve 25 is opened and the switching valve 24 is closed, and the untreated harmful gas is discharged into the combustion type exhaust gas treatment apparatus A downstream from the switching valve 24. The combustion operation is stopped so that no components remain. Note that the timing of closing the switching valve 24 may be performed, for example, when the amount of harmful components in the exhaust gas flowing through the exhaust gas introduction path 11 decreases according to the operation state of the semiconductor manufacturing apparatus or the like, or The process may be performed after introducing the diluent gas from the dilution gas introduction path 27 to an appropriate position in the exhaust gas introduction path 11 to reduce the concentration of harmful components flowing into the combustion type exhaust gas treatment apparatus A. In any case, it is sufficient that no harmful component having a concentration equal to or higher than the specified concentration remains in the combustion type exhaust gas treatment apparatus A (in the combustion chamber 14).

After the switching valve 24 is closed and it is confirmed by a temperature sensor (not shown) that the temperature in the combustion chamber 14 has been sufficiently cooled, water or the like is sprayed from the spray nozzle 16 to deposit on the inner wall surface. Is removed. During this time, the exhaust gas containing harmful components discharged from the semiconductor manufacturing equipment and the like flows into the exhaust gas introduction route 1
1 flows to the branch route 23, is subjected to the abatement treatment by the abatement agent in the abatement cylinder B, and is exhausted from the exhaust passage 26.

Accordingly, the exhaust gas elimination process by the elimination cylinder B can be continued even while removing the deposits of the combustion type exhaust gas treatment device A and performing other maintenance work. Operation can be continued, and productivity can be significantly improved.

When an abnormal operation of the combustion type exhaust gas treatment device A occurs and the combustion type exhaust gas treatment device A is urgently stopped, the harmful components are prevented from being discharged from the treatment gas exhaust passage 12 immediately. The vacuum pump 20 is stopped, and the switching valve 25 of the branch path 23 is opened to introduce the exhaust gas into the abatement cylinder B. And the combustion type exhaust gas treatment device A
In order to discharge harmful components remaining from the combustion chamber 14 to the inlet side switching valve 24 from the combustion chamber 14, the valve 22a
Is opened, a purge gas such as nitrogen gas is introduced into the combustion chamber 14 in the reverse direction from the purge gas introduction path 22, and a gas containing harmful components is caused to flow toward the branch path 23, and is introduced into the detoxification cylinder B to perform the detoxification treatment. I do. After sufficiently purging the combustion chamber 14, the switching valve 24 is closed and the valve 22a is closed.

As a result, the harmful components and the combustion components in the combustion chamber 14 are purged, so that they do not rapidly burn and cause an explosion when the operation is restarted, and a maintenance operation for eliminating the operation abnormality. For example, even if the combustion-type exhaust gas treatment device A is disassembled and inspected, no harmful components are released, so that the operation can be performed safely.

At this time, the purge gas can be introduced from the combustion burner 13 or the gas nozzle 17 without providing the purge gas introduction path 22.
By introducing the purge gas from the downstream side of the combustion chamber 14 by the method 2, harmful components and the like in the combustion chamber 14 can be efficiently discharged to the abatement cylinder B.

Further, similarly to the above, since the exhaust gas abatement process can be continuously performed in the abatement cylinder B, it is not necessary to stop the semiconductor manufacturing apparatus and the like, and the film forming operation of the wafer during the film formation can be performed. The process can be performed to the end, the wafer does not become a defective product, and the loss of the wafer can be eliminated.

In addition, by introducing a diluent gas from the diluent gas introduction path 27 in accordance with the processing capacity of the abatement agent and reducing the concentration of harmful components, the abatement process in the abatement cylinder B can be performed more reliably. it can. Further, when the operation state of the semiconductor manufacturing apparatus or the like does not use toxic components or harmful components, for example, when the exhaust gas composition is nitrogen and hydrogen, Exhaust gas can be released into the atmosphere simply by introducing such a diluent gas to lower the hydrogen concentration.

Further, in addition to the abatement cylinder B described above, other abatement means, for example,
A well-known wet-type abatement apparatus can be used, but in the case of the abatement cylinder B filled with the dry abatement agent, the abatement can be performed only by providing a filling cylinder and simple piping and valves. The treatment does not require any operation such as heating, cooling, circulation of liquid, etc., does not require various utilities, and can perform detoxification treatment only by introducing exhaust gas. Most suitable as processing means. Especially,
By using cupric hydroxide as a dry abatement agent, various harmful components used in a semiconductor manufacturing apparatus or the like can be efficiently and reliably removed.

The valves provided in each path are usually
Although an automatic valve that automatically opens and closes according to the flow rate and temperature of each part is used, the switching valve 24 at the inlet of the combustion type exhaust gas treatment device A is used.
By using a valve that closes during a power failure and a valve that opens during a power failure as a switching valve 25 of the branch path 23, even when a power failure occurs, exhaust gas is instantaneously introduced into the abatement cylinder B to perform abatement processing. Safety can be further improved.

The structure and shape of the combustion type exhaust gas treatment device A are arbitrary, and a conventionally used combustion type exhaust gas treatment device can be used.

[0031]

【Example】

Example 1 The abatement cylinder B was filled with an abatement agent containing cupric hydroxide as a main component using an apparatus having the configuration shown in FIG. As the gas corresponding to the exhaust gas discharged from semiconductor manufacturing equipment, etc.,
A test gas containing 3% silane in nitrogen gas was used. The test gas was introduced into the combustion type exhaust gas treatment device A at 9.0 m ³ per hour to perform the combustion detoxification treatment. At this time, the silane concentration in the processing gas discharged from the processing gas exhaust passage 12 was less than 1/10 of the allowable concentration of 5 ppm.

After a lapse of 3 hours, the switching valve 25 was opened and the switching valve 24 was closed, and the test gas was introduced into the abatement cylinder B from the branch path 23 to perform the abatement treatment.

In the combustion type exhaust gas treatment apparatus A, the switching valve 24
After closing, the combustion operation of the combustion burner 13 was stopped after 30 minutes in consideration of the time during which the test gas remaining from the switching valve 24 to the combustion chamber 14 disappeared. Then, when the temperature of the combustion chamber 14 became 50 ° C. or less, water was sprayed from the spray nozzle 16 to remove deposits. Thereafter, the pilot burner 15 and the combustion burner 13 are ignited. When the temperature of the combustion chamber 14 exceeds 200 ° C., the switching valve 24 is opened, the switching valve 25 is closed, and the abatement processing by the combustion type exhaust gas treatment device A is restarted. did.

The silane concentration in the gas discharged from the abatement cylinder B to the exhaust path 26 until the operation of the combustion type exhaust gas treatment apparatus A was restarted was less than 1/10 of the allowable concentration.

Example 2 A nitrogen gas containing 5,000 ppm of silane was used as a test gas.
Was stopped suddenly, and at the same time, the switching valve 24 of the branch path 23 was opened to start the abatement process by the abatement cylinder B.
At the same time, the vacuum pump 20 was stopped, and the pilot burner 15 was extinguished.

The valve 22a of the purge gas introduction path 22 was opened to introduce nitrogen gas into the combustion chamber 14 at a rate of 6 m ³ per hour, and the gas in the combustion chamber 14 was caused to flow back to the detoxification cylinder B.
No silane was detected in the gas in the combustion chamber 14 after the purging with nitrogen gas for 30 minutes. In addition, the restart of the combustion type exhaust gas treatment device A could be performed without any problem.

As in the first embodiment, the silane concentration in the gas discharged from the abatement cylinder B to the exhaust passage 26 between the emergency stop of the combustion type exhaust gas treatment apparatus A and the resumption of operation is 1/1 / the allowable concentration. It was less than 10.

[0038]

As described above, according to the exhaust gas treatment apparatus of the present invention, even when the combustion-type exhaust gas treatment apparatus is stopped, the exhaust gas elimination processing can be continuously performed. There is no need to stop operation such as
The occurrence of defective products can be prevented, and the productivity does not decrease. In particular, by using the abatement cylinder filled with the abatement agent, it is possible to reduce the equipment cost and operating cost,
The installation space can be reduced. Also, it can easily cope with existing facilities.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an example of an exhaust gas treatment device of the present invention.

[Explanation of symbols]

A: combustion type exhaust gas treatment device, B: abatement cylinder, 11: exhaust gas introduction path, 12: treated gas exhaust path, 13: combustion burner, 14: combustion chamber, 15: pilot burner, 16 ...
Spray nozzle, 17 gas nozzle, 18 cooling water nozzle, 19 exhaust chamber, 20 vacuum pump, 21 gas-liquid separator, 22 purge gas introduction path, 23 branch path, 2
4, 25: switching valve, 26: exhaust path

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Maya Yamada, Inventor 3054-3 Shimokurosawa, Takane-cho, Kita-Koma-gun, Yamanashi Prefecture Inside Nihon Oki Co., Ltd. (72) Akihiko Nitta 3054-3 Shimo-Kurosawa, Takane-cho, Kita-Koma-gun, Yamanashi Japan Oxygen Co., Ltd.

Claims (3)

[Claims] 1. An exhaust gas treatment apparatus comprising a combustion type exhaust gas treatment apparatus for burning and removing harmful components in exhaust gas, wherein a branch path is provided in an exhaust gas introduction path for introducing exhaust gas to the combustion type exhaust gas treatment apparatus. The branch path includes abatement treatment means different from the combustion type exhaust gas treatment apparatus, and a switching valve for switching an exhaust gas path to the combustion type exhaust gas treatment apparatus and the abatement treatment means of the branch path is provided. Exhaust gas treatment equipment characterized. 2. The abatement processing means provided on the branch route,
2. The exhaust gas treatment device according to claim 1, wherein the exhaust gas treatment device is a detoxifying cylinder filled with a detoxifying agent for detoxifying a harmful component in exhaust gas by adsorption or the like. 3. The exhaust gas according to claim 1, further comprising a purge gas introduction path for discharging the exhaust gas remaining in the combustion type exhaust gas treatment apparatus toward the abatement processing means provided in the branch path. Processing equipment.