JP3117566B2 - Combustion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus for burning various fuels such as gas and petroleum, and more particularly to a combustion apparatus employing a concentration combustion method.

[0002]

2. Description of the Related Art Conventionally, it has been known that a concentration combustion method, that is, a method of burning a rich mixture and a lean mixture is effective in reducing NOx in combustion exhaust gas. Problems have been pointed out. (1) The rich mixture becomes deficient in oxygen, and the flame is disturbed and lifts easily, generating large combustion noise. (2) When the capacity of the combustor is reduced by narrowing the input, the light flame is formed at a position away from the rich flame, so that the interference action between the two flames is insufficient and unstable, and the poor combustion is likely to occur. .

In order to solve the above problem, for example, in Japanese Patent Laid-Open Publication No. Hei 3-247907, a flame-holding wall is extended above a flame outlet for jetting a rich mixture, and the flame-holding wall is extended. A discharge port is formed in the discharge port, and a means for switching and supplying the secondary air and the light air-fuel mixture is provided in the discharge port. Combustion devices configured to discharge have been proposed.

[0004]

However, according to this conventional apparatus, the secondary air and the lean air-fuel mixture are switched and discharged from the same discharge port. Therefore, a switching valve, a sensor for setting a switching timing, and the like are used. However, there is a disadvantage that the apparatus is complicated and expensive.

An object of the present invention is to provide a combustion apparatus which can effectively reduce NOx in combustion exhaust gas with a simple and inexpensive structure.

[0006]

In order to solve the above-mentioned problems, a combustion apparatus according to the present invention is provided with a rich mixture outlet for injecting a gas-rich rich mixture upward, and is maintained above the rich mixture outlet. A flame wall surface is extended, and a secondary air discharge port that discharges secondary air and a light mixture gas outlet that discharges air-rich light mixture are separated by a partition plate on the flame holding wall. <br></RTI> provided in separate areas.

[0007] Preferably, the light mixture outlet is provided in a region closer to the rich mixture outlet than the secondary air outlet. Further, a secondary air discharge port different from the secondary air discharge port is provided on the flame-holding wall surface in a region closer to the rich mixture gas ejection port than the light mixture gas ejection port.

[0008]

According to the combustion apparatus of the present invention, the lean air-fuel mixture is ejected from the direction perpendicular to the rich air-fuel mixture. Is completely and stabilized, and NOx can be effectively reduced.
In addition, since the secondary air discharge port and the light mixture gas injection port are separately provided on the flame stabilizing wall, means for switching and supplying the secondary air and the light mixture gas is not required, and the entire apparatus is not required. Simple and inexpensive construction.

If the light mixture gas outlet is provided in a region closer to the rich mixture outlet than the secondary air discharge port, the light flame is formed so as to overlap with the rich flame. In addition, poor combustion can be prevented. Also, if another secondary air discharge port is provided in a region closer to the rich mixture jet than the light mixture jet, the secondary air is directly supplied to the rich mixture jet, so that especially the rich flame Lifting can be prevented and flame holding can be improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2 show the entire combustion device, and FIGS. 3 and 4 show main parts of the combustion device.
5 and 6 illustrate the operation of the combustion device.

In FIG. 1, reference numeral 1 denotes a rich mixture jet port for injecting a gas-rich rich mixture upward, 2 denotes a flame holding wall surface extending above the rich mixture gas jet port 1, and 3 denotes a flame holding wall surface 2.
And a slit-shaped discharge port formed to extend vertically. The slit-shaped discharge port 3 is vertically divided by a partition plate 4. A secondary air discharge port 5 for discharging secondary air is provided in a region above the slit-shaped discharge port 3. In the lower region of the slit-shaped outlet 3, that is, in a region closer to the rich mixture outlet 1 than the secondary air outlet 5, there is provided a light mixture outlet 6 for ejecting an air-rich light mixture. .

In FIG. 2, 7 is a rich mixture supply pipe connected to the rich mixture jet port 1, 8 is a light mixture supply pipe connected to the light mixture jet port 6, and 9 is a secondary equipped with a fan and the like. It is an air supply unit. In FIG. 3, the solid arrow indicates the flow path of the rich mixture, the dashed-dotted arrow indicates the flow path of the light mixture, and the two-dot dashed arrow indicates the flow path of the secondary air.

In the combustion apparatus having the above-described structure, as shown in FIG. Spouts in a direction perpendicular to the direction. For this reason, as shown in FIGS. 5 and 6, in both cases of large capacity and small capacity,
The interference between the rich flame 10 and the light flame 11 is completely and stabilized, and NOx can be effectively reduced.

Further, since the light mixture jet port 6 is provided in a region closer to the rich mixture jet port 1 than the secondary air discharge port 5, as shown in FIG. Is formed so as to overlap with the rich flame 10, and the light flame 11 is formed.
, And the incomplete combustion can be reliably prevented. Moreover, since the secondary air discharge port 5 and the light mixture gas outlet 6 are separately provided in the slit-shaped discharge port 3 of the flame stabilizing wall 2, unlike the conventional case, the secondary air and the light mixture gas are switched. There is also an advantage that the means for supplying the pressure is not required, and the whole apparatus can be simply and inexpensively constructed.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the drawing, the same reference numerals and arrows as those in the first embodiment indicate the same members and flow paths.

In the combustion apparatus according to the second embodiment, a secondary air discharge port 12 different from the secondary air discharge port 5 is provided at the slit-shaped discharge port 3 of the flame-holding wall surface 2 with a light mixture gas discharge port 6. It is provided in a region closer to the rich mixture jet port 1 than in FIG. In this case, the secondary air is discharged from the uppermost portion and the lowermost portion of the slit-shaped discharge port 3, and the lowermost secondary air is directly supplied to the rich flame 10. For this reason, it is possible to increase the flame holding power of the rich flame 10 and reliably prevent the lift.

The present invention is not limited to the above embodiments, but may be embodied by appropriately changing the shape and configuration of each part as exemplified below. (1) As shown in FIG. 9, a second rich mixture ejection port 13 is provided in a part of the slit-shaped ejection port 3. In the illustrated example, the slit-shaped outlet 3 includes, in order from the bottom, a secondary air outlet 5, a light mixture outlet 6, a secondary air outlet 5, a second rich mixture outlet 13, and a light mixture outlet 6. Is provided. (2) As shown in FIG. 10, the slit-shaped discharge ports 3 are further subdivided, and the secondary air discharge ports 5 and the light mixture gas discharge ports 6 are alternately arranged there. (3) As shown in FIG. 11, a guide 14 such as a paring is provided at the slit-shaped discharge port 3 so as to protrude toward the combustion space. In this case, combustion noise can be reduced more effectively. (4) A secondary air discharge port and a light mixture gas discharge port are formed in an arbitrary shape such as a round hole or a square hole on a wall for flame holding. (5) The means for supplying the rich mixture, the lean mixture, and the secondary air should be changed as appropriate.

[0018]

As described above in detail, according to the first aspect of the present invention, the secondary air discharge port and the light mixture gas discharge port are provided in different areas on the flame stabilizing wall, respectively. NOx can be effectively reduced with an inexpensive structure.

According to the second aspect of the present invention, since the lean mixture jet is provided in a region closer to the rich mixture jet than the secondary air discharge port, the stability of the lean flame at the time of small capacity is increased,
Poor combustion can be prevented.

According to the third aspect of the present invention, since another secondary air discharge port is provided in a region closer to the rich mixture jet than the light mixture jet, the lift of the rich flame is prevented, and the flame holding property is prevented. Can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an entire combustion device of a first embodiment according to the present invention.

FIG. 2 is a schematic diagram showing a vertical cross-sectional shape of the combustion device of FIG.

FIG. 3 is a schematic view showing a main part of FIG. 2;

FIG. 4 is a schematic view of a main part of FIG. 3 as viewed from the front side.

FIG. 5 is an explanatory diagram showing an operation at the time of large capacity.

FIG. 6 is an explanatory diagram showing an operation at the time of a small capacity.

FIG. 7 is a schematic view showing a main part of a combustion apparatus according to a second embodiment of the present invention.

FIG. 8 is a schematic view of a main part of FIG. 7 as viewed from the front side.

FIG. 9 is a schematic diagram showing a modified example of the present invention.

FIG. 10 is a schematic diagram showing another modification of the present invention.

FIG. 11 is a schematic view showing a modification of the slit-shaped discharge port.

[Explanation of symbols]

1. ··············································································· Secondary air discharge port
6 ·······································································
Light air mixture supply pipe, 9 secondary air supply section, 10 rich flame, 11 fresh flame, 12 separate secondary air discharge port, 1
3 ···· 2nd rich mixture jet, 14 ··· guide.

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F23D 14/02-14/10 F23C 11/00

Claims (3)

(57) [Claims] 1. A fuel / fuel mixture outlet for discharging a gas-rich gas / fuel mixture upward, a flame holding wall extending above the gas / fuel mixture outlet, and secondary air discharged to the flame holding wall. A combustion apparatus characterized in that a secondary air discharge port and a light-air mixture outlet for ejecting an air-rich light-air mixture are provided in separate areas by a partition plate . 2. The combustion apparatus according to claim 1, wherein the light mixture gas ejection port is provided in a region closer to the rich mixture gas ejection port than the secondary air discharge port. 3. The flame stabilizing wall in a region closer to the rich mixture outlet than the light mixture outlet is provided with a secondary air outlet different from the secondary air outlet. Combustion equipment.