JPH08261416A - Method of promoting combustion of gas burner, and gas burner - Google Patents

Abstract

PURPOSE: To hold back an increase of the volume of a burner to the utmost and to enhance specific combustion intensity by a method wherein fuel gas and air for combustion are introduced separately to a common porous permeable solid having a heat resistance and vents communicating with and continuous to one another and the gas and the air are mixed by passing them through the permeable solid and supplied to a combustion chamber. CONSTITUTION: An air/fuel mixer 3 is constructed of a porous permeable solid (a) having a heat resistance and a large number of vents communicating with and being continuous to one another and it is incorporated in the front half part of a main body part 2a of a burner casing 2 so that some vacant space exists between the outer peripheral surface thereof and the inner peripheral surface of the main body part 2a. A combustion chamber 9 is constituted of a space surrounded by the mixer and a cap part 2b, while a passage 10 for supplying air for combustion, which is constituted of the vacant space, is provided in the periphery of the combustion chamber. Fuel gas supplied through a fuel gas supply passage 7 and the air for combustion supplied through the passage 10 from a port 4 for introducing the air for combustion pass through the air/fuel mixer 3 from the porous permeable solid (a) and sent into the combustion chamber 9.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for promoting combustion in a gas combustor such as a gas burner and a gas combustor used directly for carrying out the method.

[0002]

2. Description of the Related Art Gas combustors such as burners that are widely used for industrial purposes are usually equipped with the exception of a complete premix burner.
Fuel gas and air are separately introduced into a combustor, mixed there, and then burned. Therefore, many parts of the combustor are used for mixing fuel and air, and the load factor of the calorific value per volume is lowered. Also, since the rise in the temperature of the combustor body causes destruction of the combustor, conventionally, when cooling is required, cooling air is flown along the body, but this also increases the volume of the combustor. Invite. Further, when preheating using combustion heat is performed as needed, a method of newly providing a flow path, fins or the like may be adopted, but this also causes an increase in the volume of the combustor.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art. The object of the present invention is to suppress the increase in the volume of the combustor as much as possible and increase the combustion load factor. It is in.

[0004]

In order to achieve the above object, in the combustion promoting method for a combustion apparatus according to the present invention, a common porous ventilation having heat resistance and having a large number of ventilation holes communicating with each other is provided. The fuel gas and the combustion air are separately guided to the volatile solid, and these are mixed by passing through the permeable solid and supplied to the combustion chamber.

Further, in order to carry out this method, in the combustor of the present invention, an air-gas mixer is formed by a porous air-permeable solid having heat resistance and having a large number of air holes continuously communicating with each other. The fuel gas supply passage and the combustion air supply passage are connected to the combustion chamber through the wall of the air / gas mixer with the heat resistance. In this combustor, it is desirable that the inlet for the combustion air into the wall of the air / gas mixer is provided outside the inlet for the fuel gas.

[0006]

In the method for promoting combustion of the gas combustor and the gas combustor configured as described above, the fuel gas fed into the porous permeable solid and the combustion air are mixed in the porous permeable solid. It is then supplied to the combustion chamber and burns in the combustion chamber. The combustion heat at this time is somewhat returned to the inside of the porous air-permeable solid, but this is used for preheating the combustion air, and conversely, the combustion air is warmed to suppress the temperature rise of the combustor body.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In this example, the combustor is a high speed gas burner. In the figure, A is a combustor, and a cylindrical burner casing 2 having a combustion gas ejection port 1 at its tip has a cylindrical air / gas mixer 3 whose inner diameter gradually increases toward one end. The large-diameter side opening is installed toward the combustion gas ejection port 1 side.

The burner casing 2 is a cylindrical main body.
2a and a cap portion 2b whose inner surface screwed into the opening of the main body portion 2a has a spherical shape, and the combustion gas ejection port 1 has the main body portion.
It is opened at the center of the cap portion 2b on the extension of the axis of 2a. Further, the burner casing 2 has a main body part.
A combustion air introduction port 4 is opened in the rear peripheral surface of 2a, and a fuel gas supply pipe 5 is inserted into the burner casing 2 penetrating the rear end, and the front end of the fuel gas supply pipe 5 is It is fitted into the small-diameter side opening of the air / gas mixer 3.

The fuel gas supply pipe 5 has a pilot burner 6 coaxially incorporated therein, and a gap between the inner surface of the pipe 5 and the pilot burner 6 constitutes a fuel gas supply passage 7 for the main flame. Although the tip of the fuel gas supply passage 7 is closed, the peripheral surface of the fuel gas supply pipe 5 has an opening 8 at the portion where the fuel gas supply pipe 5 is fitted into the small diameter side opening of the air / gas mixer 3. The opening 8 is in close contact with the inner peripheral surface of the air / gas mixer 3, and the fuel gas is ejected from the inside of the air / gas mixer 3. The flame burner 63 of the pilot burner 6 is located near the small-diameter side opening of the air / gas mixer 3 and faces the combustion chamber 9. 61 is a fuel gas supply passage for the pilot burner,
Reference numeral 62 is a combustion air supply passage for the pilot burner.

On the other hand, the air / gas mixer 3 is made of, for example, alumina-based ceramic, sintered metal, cement or the like, has heat resistance, and has a porous gas permeability having a large number of ventilation holes communicating with each other. It is made of solid a and is incorporated in the front half of the main body 2a so that there is a slight gap between the outer peripheral surface of the solid a and the inner peripheral surface of the main body 2a of the burner casing 2, which is surrounded by the cap 2b. The combustion chamber 9 is constituted by the space formed, and a combustion air supply passage 10 constituted by the above-mentioned gap is provided on the outer periphery thereof. The combustion air supply passage 10 communicates with the combustion air inlet 4.
Further, the front end of the combustion air supply passage 10 has a suitable pressing member 11
Alternatively, the burner casing 2 is closed by a step provided on the cap 2b.

The air / gas mixer 3 is divided into a front member 3a and a rear member 3b, and a flame-holding ring 12 is sandwiched between the both members 3a and 3b to form a cylindrical basket-shaped holder. It is contained in 13. The holder 13 has a plurality of protrusions 131 on the outer surface thereof, and the protrusions 131 are brought into contact with the inner surface of the burner casing main body portion 2a to form a space forming the combustion air supply passage 10 between the holder 13 and the inner surface of the burner casing main body portion 2a. Is provided. The rear member 3b of the air / gas mixer 3 is formed to have a smaller porosity than that of the front member 3a, or the ventilation hole is formed to have a small diameter.

Thus, in the gas combustor A having such a structure, the fuel gas supplied through the fuel gas supply passage 7 and the combustion air supplied from the combustion air introduction port 4 through the combustion air supply passage 10 are used. The air is sent into the combustion chamber 9 through the air / gas mixer 3 made of a porous air-permeable solid a having a large number of continuous vent holes, and the air / gas mixer 3 By passing both the fuel gas and the combustion air through the porous gas-permeable solid a constituting the above, these are mixed and stirred with each other in the porous gas-permeable solid A and burned in the state of a completely mixed air-fuel mixture. It is supplied to the chamber 9.

Further, the combustion air supplied from the combustion air inlet 4 and flowing through the combustion air supply passage 10 formed along the outer peripheral surface of the air / gas mixer 3 cools the surface of the gas / air mixer 3. While suppressing the temperature rise of the burner casing 2, this air is preheated by taking in combustion heat while passing through the mixer 3 from the outer peripheral surface side of the air / gas mixer 3 and reaching the combustion chamber 9.

In the embodiment described above, the fuel gas supply path 7
Is closed, and all the fuel gas is supplied from the opening 8 provided on the peripheral surface of the fuel gas supply pipe 5 at the portion where the fuel gas supply pipe 5 is fitted into the small diameter side opening of the air / gas mixer 3. Although it is designed to eject to the mixer 3, as shown in FIG. 3, an opening 14 is provided at the tip of the fuel gas supply passage 7 so that a part of the fuel gas is directly ejected to the combustion chamber 9. It is also possible.

Further, as shown in FIG. 4, the base of the air / gas mixer 3 made of a porous air-permeable solid a is partially divided into a plurality of parts by a partition plate 15 made of a metal plate or the like over an appropriate range. The layers are horizontally partitioned into, for example, three layers, and these layers are respectively formed as air flow layers 16 and 18 and a gas layer 17 so that the vent holes do not communicate with each other for the first time before these layers. The combustion air and the fuel gas may be inserted in parallel from the base end surface of the mixer 3 into the porous air-permeable solid a constituting the mixer 3 via the supply passage 7 and the combustion air supply passage 10. . In this case, at least the outermost layer serves as an air flow layer. As a result, the temperature rise of the burner casing 2 can be suppressed without providing the combustion air supply passage 10 along the outer peripheral surface of the air / gas mixer 3 as in the above-described embodiment.

[0016]

The present invention is configured as described above, and has the following effects. The fuel gas and the combustion air are communicated with each other and passed through a common porous air-permeable solid having a large number of continuous ventilation holes and fed into the combustion chamber, so that the mixing of the fuel gas and the combustion air is promoted and blown out. The effect of stirring the air-fuel mixture is improved. Therefore, the part required for mixing the fuel gas and the combustion air in the combustor becomes small,
It is possible to suppress the increase in the volume of the combustor as much as possible and increase the combustion load factor.

The air layer formed by the combustion air fed into the porous air-permeable solid has the effect of insulating the heat transfer of combustion heat to the combustor body, so that the temperature rise of the combustor body is prevented. Therefore, it is not necessary to take measures such as flowing cooling air along the main body, and the increase in volume of the combustor can be suppressed.

Since the combustion air is preheated by taking in the combustion heat while passing through the porous air-permeable solid and reaching the combustion chamber, it is not necessary to provide a special passage or fin for preheating, and the combustor is not required. It is possible to suppress an increase in volume.

[Brief description of drawings]

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

FIG. 2 is an exploded perspective view of a main part.

FIG. 3 is a sectional view showing a modified example of a main part.

FIG. 4 is a sectional view showing another embodiment.

[Explanation of symbols]

a: porous air-permeable solid 3: air / gas mixer 7: fuel gas supply passage 9: combustion chamber 10: combustion air supply passage

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hidenobu Matsushita 1-17-1 Chiyo, Hakata-ku, Fukuoka-shi, Fukuoka Seibu Gas Co., Ltd. No. 1 in Seibu Gas Co., Ltd.

Claims (3)

[Claims] 1. A fuel gas and combustion air are separately guided to a common porous permeable solid having heat resistance and a large number of ventilation holes communicating with each other continuously, and these are passed through the permeable solid. A method for accelerating combustion in a gas combustor, characterized in that the mixture is mixed and supplied to a combustion chamber. 2. An air / gas mixer is formed of a porous gas-permeable solid having heat resistance and having a large number of air holes continuously communicating with each other, and the fuel gas supply passage and the combustion air supply passage are formed as described above. A gas combustor characterized in that its heat resistance is communicated to the combustion chamber through the wall of the air / gas mixer. 3. The gas combustor according to claim 2, wherein the inlet for the combustion air to the wall of the air / gas mixer is provided outside the inlet for the fuel gas.