JPH10294308A - External combustion device for wet oxidation furnace - Google Patents

Abstract

(57) [Problem] To eliminate the risk of devitrification or melting of a combustion tube due to the combustion flame of hydrogen gas and oxygen gas reaching the inner wall of the combustion tube. SOLUTION: An external combustion apparatus for a wet oxidation furnace generates steam 9 to be supplied to a wet oxidation furnace by ejecting hydrogen gas 7 and oxygen gas 8 from nozzles into a combustion tube 11 and burning them by heating. Let it. The end wall 11a of the combustion tube opposite to the outlet 12 for the steam 9 generated in the combustion tube 11
An annular oxygen gas supply nozzle 14 is provided in the vicinity. A hydrogen gas supply nozzle 13 is provided at the center of the annular oxygen gas supply nozzle 14, and a hydrogen gas outlet 13 a of the hydrogen gas supply nozzle 13 is opened toward the outlet 12. The oxygen gas outlet 14a of the oxygen gas supply nozzle 14 is opened toward the water vapor outlet 12 so as to surround the hydrogen gas outlet 13a. The oxygen gas outlet 14a is arranged at a position protruding from the hydrogen gas outlet 13a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external combustion apparatus for supplying steam to a wet oxidizing furnace in a semiconductor manufacturing facility, and more particularly, to supplying hydrogen gas and oxygen gas into a quartz combustion tube for heating. Further, the present invention relates to an external combustion device for a wet oxidation furnace that generates a steam to be supplied to the wet oxidation furnace by causing a combustion reaction.

[0002]

2. Description of the Related Art FIG. 4 shows a schematic configuration of a conventional external combustion device N1. The external combustion device N1 has a combustion tube 1 made of quartz, and a leading end 2 of the combustion tube 1 is provided with an outlet 2 for leading steam 9 toward a wet oxidation furnace (not shown). . A hydrogen gas supply nozzle 3 made of quartz and an oxygen gas supply nozzle 4 are inserted in parallel at an end wall 1a of the combustion tube 1 opposite to the outlet 2 at a fixed distance.
At the tip of the hydrogen gas supply nozzle 3, a hydrogen gas ejection port 3 a facing forward is provided, and at the side of the tip of the oxygen gas supply nozzle 4, an oxygen gas ejection port 4 a facing the hydrogen gas supply nozzle 3 side is provided. Have been. A hydrogen gas 7 is introduced into the hydrogen gas supply nozzle 3, and an oxygen gas 8 is introduced into the oxygen gas supply nozzle 4. The introduced hydrogen gas 7 and oxygen gas 8 are ejected into the combustion tube 1 from the ejection ports 3a, 4a of the nozzles 3, 4, and are heated by the heater 6 to cause a combustion reaction to generate steam 9. Then, the steam 9 is sent from the outlet 2 to the wet oxidation furnace.

[0003]

By the way, in the above-mentioned conventional external combustion device N1, since the flame H is elongated from the tip of the hydrogen gas supply nozzle 3, the supply amount of the hydrogen gas 7 is increased in order to increase the amount of water vapor. However, there is a problem that the flame H extends too much and reaches the inner wall of the combustion tube 1, and as a result, the combustion tube 1 is overheated and devitrified or melted.

[0004] In view of the above circumstances, the present invention provides a wet oxidation furnace which can normally generate steam without fear of devitrification or melting of the combustion tube even if the supply amount of hydrogen gas is increased to increase the amount of steam. The purpose of the present invention is to provide an external combustion device for use.

[0005]

According to the present invention, hydrogen gas and oxygen gas are ejected from a nozzle into a combustion tube and heated to burn the hydrogen gas, thereby generating steam for supply to a wet oxidation furnace. In an external combustion device for a wet oxidation furnace, an annular oxygen gas supply nozzle is provided near an end wall of the combustion tube on the side opposite to the outlet of steam generated in the combustion tube, and the annular oxygen gas supply nozzle is provided. A hydrogen gas supply nozzle is provided at the center of the hydrogen gas supply nozzle, and a hydrogen gas ejection port of the hydrogen gas supply nozzle is opened toward the water vapor outlet, and an oxygen gas ejection port of the oxygen gas supply nozzle is connected to the hydrogen gas ejection nozzle. An opening is provided so as to surround the outlet so as to face the water vapor outlet, and the oxygen gas outlet is disposed at a position protruding from the hydrogen gas outlet. .

In this apparatus, since the oxygen gas outlet surrounds the hydrogen gas outlet at the center in a ring shape from the periphery, the oxygen gas is widely diffused and ejected around the hydrogen gas. Further, since the oxygen gas ejection port projects forward from the oxygen gas ejection port, the oxygen gas is ejected at a position forward of the hydrogen gas ejection location. For this reason, the flame does not directly and elongate from the tip of the hydrogen gas supply nozzle, but rather exits from a position close to the outlet of the annular oxygen gas supply nozzle around the nozzle. Therefore, the generated flame has a short and thick shape, and the end of the flame does not reach the inner wall of the combustion tube.

[0007] In the above invention, it is preferable that the oxygen gas jet opening is inclined and opened toward the front of the center of the oxygen gas supply nozzle. When the oxygen gas outlet is inclined toward the front of the center of the oxygen gas supply nozzle in this manner, the oxygen gas is ejected toward the hydrogen gas ejected from the hydrogen gas outlet, and the combustion reaction is accelerated. Is done.

Further, the two nozzles are disposed at the tip of a double pipe joined to the end wall of the combustion pipe, and a gas passage in an inner pipe of the double pipe is communicated with the hydrogen gas supply nozzle. It is preferable that a gas passage between the inner tube and the outer tube be communicated with the oxygen gas supply nozzle. In this way, hydrogen gas can be supplied through the passage inside the inner tube of the double tube, and oxygen gas can be supplied through the passage between the inner tube and the outer tube of the double tube, and the annular oxygen Oxygen gas and hydrogen gas can be stably supplied to the gas supply nozzle and the hydrogen gas supply nozzle at the center thereof.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view showing a schematic configuration of an external combustion apparatus N according to an embodiment, FIG. 2 is a side sectional view of a main part thereof, and FIG. 3 is a front view of FIG. The combustion tube 11 of the external combustion device N is entirely made of quartz, and has an outlet 12 for water vapor 9 on the tip side. An annular oxygen gas supply nozzle 14 is provided near the end wall 11a of the combustion tube on the opposite side of the outlet port 12 at the center of the end wall 11a. Is provided.

The annular oxygen gas supply nozzle 14 secures a bag-shaped annular space 14b on the inner surface side of the end wall 11a of the combustion tube, and a front wall 14c forming the space 14b faces the outlet port 12 direction. A large number of oxygen gas outlets 14a are opened. The oxygen gas outlet 14a in this case is
As shown in FIG. 2, it is inclined slightly forward of the center of the oxygen gas supply nozzle 14 and toward the center of the combustion tube 11, and as shown in FIG. 3, an appropriate interval is provided so as to surround the center. And are distributed.

At the center of the oxygen gas supply nozzle 14, a tip wall 13b of the hydrogen gas supply nozzle 13 is provided so as to be recessed one step from the front wall 14c. 13a is opened facing the outlet 12 direction. Therefore, the oxygen gas outlet 14a is located at a position protruding forward from the hydrogen gas outlet 13a.

Further, a tip of a double pipe 15 is joined to the outside of the combustion pipe end wall 11a. Hydrogen gas supply nozzle 13
The oxygen gas supply nozzle 14 is provided at the tip of the double pipe 15, and the gas passage 16 in the inner pipe 15 b of the double pipe 15 is provided.
Communicates with the jet port 13a of the hydrogen gas supply nozzle 13, and a gas passage 17 between the inner pipe 15b and the outer pipe 15a of the double pipe 15.
Communicates with the annular space 14b of the oxygen gas supply nozzle 14. Also, as shown in FIG. 1, hydrogen gas introduction pipes 19 are provided at the base ends of both gas passages 16 and 17 in the double pipe 15.
And an oxygen gas introduction pipe 18. In addition, these nozzles 13 and 14, double pipe 15, gas introduction pipe 18, 1
9 are all made of quartz integrally with the combustion tube 11. Further, a heater 6 for heating is arranged on the outer periphery of the combustion tube 11.

Next, the operation will be described.

In this apparatus, when the oxygen gas 8 and the hydrogen gas 7 are supplied from the introduction pipes 18 and 19, the hydrogen gas 7 passes through the double pipe 15 from the ejection port 13 a of the hydrogen gas supply nozzle 13 and is supplied into the combustion pipe 11. And the oxygen gas 8 is ejected from the ejection port 14 a of the oxygen gas supply nozzle 14.
Squirted into. Then, a combustion reaction occurs in the combustion pipe 11 to generate steam 9, and the steam 9 is discharged from the outlet 12.
It is supplied to a wet oxidation furnace.

At this time, since the jet port 13a of the hydrogen gas supply nozzle 13 is annularly surrounded from the periphery by the jet port 14a of the oxygen gas supply nozzle 14, the oxygen gas 8
Are widely diffused around the hydrogen gas 7 and are ejected. Also,
Since the oxygen gas ejection port 14a protrudes forward from the hydrogen gas ejection port 13a, the oxygen gas 8 is ejected at a position ahead of the location where the hydrogen gas 7 is ejected. Therefore, the reaction between the oxygen gas 8 and the hydrogen gas 7
The flame H is simultaneously generated in a wide range at a position away from the tip of the hydrogen gas supply nozzle 13, and the flame H does not directly and elongate from the tip of the hydrogen gas supply nozzle 13, but the discharge port of the annular oxygen gas supply nozzle 14 around it. It comes out from a position near 14a.

As a result, the generated flame H has a short and thick shape, and there is no possibility that the end of the flame H reaches the inner wall of the combustion tube 11. Further, since the oxygen gas ejection port 14a is inclined forward in the center of the oxygen gas supply nozzle 14,
The oxygen gas 8 is ejected toward the hydrogen gas 7 ejected from the hydrogen gas ejection port 13a, the stirring action is added, the combustion reaction is promoted, and the flame H does not extend elongated. Therefore, even when the supply amount of the hydrogen gas 7 is increased to increase the amount of generated steam, there is no possibility that the combustion tube 11 is devitrified or dissolved.

[0018]

As described above, according to the present invention, the flame does not directly and elongate from the tip of the hydrogen gas supply nozzle, but rather widens from the position close to the peripheral oxygen gas supply nozzle outlet. Comes into short shape. Therefore, there is no possibility that the end of the flame reaches the inner wall of the combustion tube, and the devitrification and melting of the combustion tube can be prevented, and the steam can be generated normally.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the embodiment of the present invention.

FIG. 3 is a front view as viewed from a direction III in FIG. 2;

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

 N External combustion device 7 Hydrogen gas 8 Oxygen gas 9 Water vapor 11 Combustion pipe 11a End wall 12 Outlet 13 Hydrogen gas supply nozzle 13a Hydrogen gas ejection port 14 Oxygen gas 14a Oxygen gas ejection port 15 Double pipe 15a Outer pipe 15b Inner pipe 16 Gas passage in inner pipe 17 Gas passage between inner pipe and outer pipe

Claims (1)

[Claims] 1. A method in which hydrogen gas and oxygen gas are ejected from a nozzle into a combustion tube and heated to burn the hydrogen gas.
In an external combustion device for a wet oxidation furnace for generating steam to be supplied to a wet oxidation furnace, an annular oxygen gas supply is provided near an end wall of the combustion tube on a side opposite to an outlet of the steam generated in the combustion tube. A nozzle is provided, and a hydrogen gas supply nozzle is provided in the center of the annular oxygen gas supply nozzle, and a hydrogen gas ejection port of the hydrogen gas supply nozzle is opened toward the water vapor outlet. The oxygen gas outlet of the nozzle was opened toward the water vapor outlet in an arrangement surrounding the hydrogen gas outlet, and the oxygen gas outlet was arranged at a position protruding from the hydrogen gas outlet. An external combustion device for a wet oxidation furnace, comprising: