JP2756074B2 - Concentration combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat rich mixing section for producing a rich air-fuel mixture having a low primary air suction ratio, and a flat lean mixing section for producing a light air-fuel mixture having a high primary air suction ratio. Parts are arranged alternately with the width direction facing in the same direction, a flame hole for a rich mixture is formed on the upper surface of the rich mixture portion, and a flame hole for a light mixture gas is formed on the upper surface of the light mixture portion. A rectifying plate is formed in the light mixing section, and a straightening plate that rectifies the light mixture flowing toward the flame hole for the light mixture in the width direction of the light mixing section is provided, and The present invention relates to a gray-scale combustion device in which a flame hole for an air-fuel mixture is formed by being divided in the width direction by the straightening plate.

[0002]

2. Description of the Related Art Conventionally, in this type of rich-and-lean combustion apparatus, the upper end of a rectifying plate that divides and mixes a lean air-fuel mixture in a width direction of a lean air-mixing section as described in Japanese Patent Application Laid-Open No. 1-219406. The height of the burner is approximately the same as that of the flame for the rich mixture, or lower than the flame of the rich mixture.

[0003]

However, as described in the above-mentioned publication, when the upper end of the straightening vane is almost the same height as the flame hole of the rich mixture, it is necessary to reduce the passing pressure loss in the light mixture portion. When the vertical width of the flow straightening plate is shortened, the lean flame is formed near the flame hole at the time of combustion in which the suction ratio of the light mixing portion is relatively small (the excess air ratio is reduced). The inconsistency of the combustion state due to interference with the rich flame and the generation of resonance noise, and the quenching effect (cooling effect)
There is a disadvantage that flashback is likely to occur due to the decrease in the pressure.If a straightening plate with a relatively long vertical width is used to prevent such a disadvantage, the passage pressure loss increases, and noise is generated. And the burden on the blower fan increases.

[0004] Even when the upper end of the flow straightening plate is lower than the flame hole of the rich air-fuel mixture, flashback occurs during combustion in which the suction ratio of the light air-mixing part is relatively small for the same reason as described above. If you increase the vertical width of the current plate to prevent flashback,
There has been a problem that noise is generated due to an increase in the passing pressure loss and a load on a blower fan or the like is increased.

The present invention solves the disadvantages of the conventional combustion apparatus while making the most of the advantages of the above-described conventional combustion apparatus. An object of the present invention is to form a flame hole for a lean mixture with a relatively simple structure. It is possible to generate a stable light flame as well as stably without flashback even during combustion with a relatively small suction ratio in the light mixing section without making the vertical width of the straightening plate relatively long. It is an object of the present invention to provide a lean-burn combustion apparatus capable of performing combustion.

[0006]

SUMMARY OF THE INVENTION A first characteristic configuration of the concentration combustion apparatus according to the present invention is that a flat rich mixing section for generating a rich air-fuel mixture having a small primary air suction ratio, and a primary air suction ratio for the rich air-fuel mixture. Flat light mixing sections that generate a large light mixture are alternately arranged with the width direction facing in the same direction, and a flame hole for the rich mixture is formed on the upper surface of the rich mixing section. A flame hole for a light mixture is formed on the upper surface of the portion, and the light mixture flowing toward the flame hole for the light mixture is divided in the width direction of the light mixture portion in the light mixture portion. A rectifying plate for rectifying, and wherein the flame hole for the lean mixture is formed by being divided in the width direction by the rectifying plate, wherein the rectifying plate has an upper end. The point is that it is provided so as to protrude above the flame for the rich mixture.

A second characteristic configuration of the concentration combustion apparatus according to the present invention specifies a preferred specific configuration for implementing the first characteristic configuration. Are stored in a state where the flat rectangular cylindrical bodies are lined up at intervals, and the dense mixing portion is formed by the rectangular cylindrical bodies, and
The light mixing portion is formed in a space surrounded by the adjacent rectangular cylindrical body and the side wall of the casing, and the rectifying plate includes:
The point is that it is attached to the rectangular tubular body.

[0008]

According to the first characteristic configuration of the present invention, the lean air-fuel mixture flowing toward the flame hole for the lean air-fuel mixture is supplied to the flat lean air-fuel mixture generating section. A rectifying plate that divides and rectifies in the width direction is provided, and the flame holes for the lean mixture are formed by being divided in the width direction by the rectifier plate, so that the flame holes for the lean mixture are formed. The air-fuel mixture flowing toward the air-fuel mixture is divided and rectified in the width direction of the air-mixing portion by the rectifying plate, and is discharged from the flame hole for the air-fuel mixture in the rectified state. In the air hole for the air-fuel mixture, a good and stable light flame uniform in the width direction of the light mixing portion is generated, and the light holes for generating the light flame are formed by the straightening plate. The plate can be used for both rectification of the lean mixture and the formation of the flame holes for the lean mixture.

In addition, since the straightening plate is provided with its upper end protruding above the flame hole for the rich mixture, when the combustion ratio of the lean mixture portion is at a predetermined level, combustion takes place. Needless to say, even during combustion in which the suction ratio of the light mixing section is relatively small, the light flame is generated near the upper end of the straightening plate, that is, above the flame for the rich mixture, and It is difficult to generate near the flame for use, and even if flashback is likely to occur, it becomes difficult for the light flame to enter the flame.

According to the second characteristic configuration, the rich mixing portion is formed by the rectangular cylindrical body, and the light mixing portion is formed by the space surrounded by the adjacent rectangular cylindrical body and the side wall of the casing. Since the current plate is attached to the rectangular cylindrical body, the rich mixing section and the light mixing section are alternately formed with a simple structure, and are surrounded by the upper surface of the rich mixing section of the rectangular cylindrical body and the upper end of the casing side wall. A straightening plate can be provided in the light mixing portion even when a light hole for the light mixture is formed in the portion where the light mixture is formed.

[0011]

According to the first characteristic configuration of the present invention, in the flame hole for the light mixture, a good and stable light flame which is uniform in the width direction of the light mixture portion is generated. Since the flame holes for generating the lean flame are formed by the straightening plate, the straightening plate can be used for both the straightening of the light mixture and the formation of the light holes for the light mixture, so that the stable combustion of the lean mixture can be achieved. In addition, the simplification of the structure and the cost reduction can be achieved by using the rectifier plate to share parts.

In addition, even in the case of combustion in which the suction ratio of the light mixing section is relatively small, a light flame is unlikely to be generated near the flame for the rich mixture, and a flashback is likely to occur. In this case, it becomes difficult for the flame to enter the flame hole, so the vertical width of the straightening vane is shortened to reduce the passing pressure loss in the light mixing section, thereby reducing noise generation and the load on the blower fan. In addition, the flow straightening plate can effectively prevent interference with the flashback or the rich flame in the light mixing section, and can provide a light-and-dark combustion apparatus in which the combustion state is stable and no resonance is generated. .

According to the second characteristic configuration, the rich mixing section and the light mixing section are alternately formed, and the flame for the light mixed gas is formed at the portion surrounded by the upper surface of the rich mixing section and the upper end of the casing side wall. Even when holes are formed, a straightening plate can be provided in the light mixing portion, so that the flame hole for the rich mixture and the flame hole for the light mixture are alternately close to each other with a simple structure. Even in the case of being formed as described above, it is possible to provide a light-and-shade combustion apparatus in which interference with flashback or rich flame in the light mixing portion is effectively prevented by the rectifying plate.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a flat rich mixture portion A that generates a rich mixture having a small suction ratio of primary air, and a flat lean mixture portion B that generates a light mixture having a large suction ratio of primary air, The flame holes 1 for the rich mixture are formed on the upper surface of the rich mixing portion A, and the flame holes 2 for the light mixture are formed on the upper surface of the light mixing portion B. A shaded burner is shown.

The rich / lean combustion apparatus burns a desired amount of combustion in a state where the combustion temperature is lowered by the lean flame while maintaining the ignitability and the flame holding effect by the rich flame, so that NO _x ( This is a combustion device capable of performing combustion with the generation of nitrogen oxides reduced as much as possible.

The concentration combustion device in this embodiment is constituted by a so-called Bunsen burner. The rich mixing section A and the light mixing section B are alternately arranged and housed inside a bottomed rectangular cylindrical casing K. The rich flame is above the flame hole 1 provided in the rich mixing section A, while the light flame is
Are respectively formed above the flame holes 2 provided in the nozzle. The casing K includes a bottom plate 5, a burner fixing plate 6 as a side wall of the casing K, and a side plate 7. The bottom plate 5 of the casing K is provided with a supply port 5a for thick mixing and a supply port 5b for light mixing corresponding to each of the rich mixing section A and the light mixing section B, and an opening area of the supply port 5b for light mixing. Is made larger than the opening area of the supply port 5a for dense mixing.

Below the bottom plate 5, there is a supply port 5a for thick mixing.
The fuel gas supply pipe 3 for rich mixing provided with an ejection nozzle 3a as an ejection part for ejecting fuel gas toward the nozzle, and the ejection as an ejection part for ejecting fuel gas toward the supply port 5b for light mixing Two light fuel gas supply pipes 4 for light mixing each having a nozzle 4b are provided. Therefore, the supply port 5a and the supply port 5 are provided for the rich mixing section A and the light mixing section B, respectively.
The fuel gas is blown through the nozzle b, and the primary air for combustion is sucked along with the fuel gas.

A casing K for accommodating the rich mixing section A and the light mixing section B, and the rich fuel gas supply pipe 3 and the light fuel gas supply pipe 4 have a bottomed rectangular cylindrical shape forming a combustion chamber of the rich / lean combustion apparatus. It is provided inside the barrel R. A gap 8 is formed around the outer periphery of the casing K by the cylinder R and the casing K.
Are formed. The gap 8 is configured to cool the casing K by the flow of the cooling air and to shut off the heat from the casing K to the barrel R.

A blower fan 9 for blowing combustion air and cooling air toward the bottom plate 5 and the gap 8 is provided at the bottom of the cylinder body R.
Fan outlet 9a is provided. Fan outlet 9
a, the flow velocity distribution of the discharge air is made more uniform,
The air conditioning plate 10 for blowing an equal amount of air to each part in the inside is provided. The air conditioner 10 is made of punching metal or the like. In general, the air-conditioning plate 10 is configured so that the opening area for the ventilation air is as large as possible so as to prevent the air-blowing effect of the blower fan 9 as much as possible while providing the air-conditioning effect. By narrowing the area or providing a plurality of air conditioning plates 10,
It is configured such that the air conditioning effect and the air blowing effect of the air blowing fan 9 can be adjusted.

FIG. 2 shows two thick mixing sections A,
A light mixing section B formed between the thick mixing sections A is shown. The dense mixing section A is composed of a flat rectangular cylindrical body a. At the lower part of the rectangular cylindrical body a, a vertically long rectangular cylindrical inlet portion 11 to which fuel gas and primary air for combustion are supplied is formed. The inlet portion 11 is configured to be located above an air supply port 5a formed in the bottom plate 5 of the casing K in a state where the square tubular body a is stored in the casing K. A flat rectangular mixing portion 12 is formed at an upper portion of the inlet portion 11. The mixing unit 12 is configured to mix fuel gas and primary air for combustion. At the center of the mixing section 12, a throttle section 13 for making the distribution of the air-fuel mixture in the mixing section 12 more uniform is provided.

A flame hole 1 for a rich mixture is formed on the upper surface of the rectangular cylindrical body a. In this embodiment, the flame holes 1 are constituted by a set of three oblong flame holes 1a, and 11 flame holes 1 are provided at an appropriate pitch for one rectangular cylindrical body a. Therefore, the fuel gas and the primary combustion air supplied to the inlet 11 through the inlet 5 a rise in the inlet 11, are mixed and diffused in the mixing unit 12, and are discharged from the flame hole 1. Forms a deep flame.

A rectifying plate 14 for rectifying the light air-fuel mixture flowing toward the flame hole 2 of the light air-mixing section B, which will be described later, is attached to both upper side surfaces of the rectangular cylindrical body a.

As shown in FIG. 3, the light mixing section B includes a plurality of flat rectangular cylindrical members a inside a bottomed rectangular cylindrical casing K.
Are stored in a line at regular intervals,
The dense mixing section A is formed in a space surrounded by the adjacent rectangular cylindrical body a and the burner fixing plate 6 as a side wall of the casing K.
And the dense mixing section A. The air supply port 5b formed in the bottom plate 5 of the casing K is provided so as to be located between the rectangular cylindrical bodies a. Therefore,
The fuel gas and the combustion primary air supplied from the air supply port 5b are mixed and diffused in the light mixing section B while being mixed in the light mixing section B.
After rising inside, and being straightened by the straightening plate 14 provided above the light mixing portion B, a flame hole for the light mixture formed between the upper surfaces of the two rectangular tubular bodies a. 2 to form a light flame.

The current plate 14 is composed of rectangular tubular members a located on both sides.
Are installed, so that two straightening plates 14 are provided for one light mixing section B. Light mixing section B
The current plate 14 promotes mixing of fuel gas and primary air for combustion, prevention of flashback at the time of low input,
And it is comprised so that the flame holding effect of a light flame may be exhibited.

That is, the flow straightening plate 14 is provided so as to rectify the light air-fuel mixture flowing toward the light-air mixture flame hole 2 in the width direction of the light air-mixing portion B and to straighten the light air-fuel mixture. The flaming holes 2 are also divided in the width direction by the rectifying plate 14. And the upper end of the current plate 14
It is formed so as to protrude above the flame hole 1 for the rich mixture. In the concentration combustion apparatus of the present embodiment, the projecting height h of the rectifying plate 14 projecting above the flame hole 1 for the rich air-fuel mixture is d such that the width between two adjacent rectangular cylindrical bodies a is d. Then, it is adjusted to 0 ≦ h ≦ d / 2.

The vertical width of the flow straightening plate 14 is such that mixing of the fuel gas and the primary air for combustion is promoted and that the lean flame is increased in a state where the passage pressure loss due to the flow resistance of the lean mixture does not unnecessarily increase. Is formed so as to reduce noise during combustion.

A plurality of projections 14a are formed on the current plate 14 and come into contact with the rectangular tubular body a and the other current plate 14 so that the gap between the rectangular tubular body a and the current plate 14 is formed. Interval,
And it is comprised so that the space | interval between the straightening plates 14 may be maintained. The distance between the rectangular tubular body a and the current plate 14 and the distance between the current plates 14 are adjusted to dimensions effective for the current plate 14 to exhibit a quenching effect (cooling effect) in a light flame. ing.

[Another Embodiment] The height h of the flow straightening plate 14 protruding above the flame hole 1 for the rich mixture is not limited to 0 ≦ h ≦ d / 2, and can be changed as appropriate.

The number of straightening plates 14 can be changed as appropriate.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the entire configuration of a concentration combustion apparatus.

FIG. 2 is a perspective view showing a thick mixing section and a light mixing section.

FIG. 3 is a cross-sectional view showing a thick mixing section and a light mixing section.

[Explanation of symbols]

 Reference Signs List A rich mixing part B light mixing part K Casing a square cylindrical body 1 flame hole for rich mixture 2 flame hole for light mixture 6 Side wall 14 straightening plate

Continuation of the front page (56) References JP-A-4-151408 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F23D 14/00-14/48 F23D 14/26-14 / 84 F23C 11/00 329

Claims (2)

(57) [Claims] 1. A flat rich mixing section (A) for producing a rich air-fuel mixture having a low primary air suction ratio, and a flat lean mixing section (B) for producing a light air-fuel mixture having a high primary air suction ratio. ) Are arranged alternately with the width direction facing the same direction, a flame hole (1) for a rich mixture is formed on the upper surface of the rich mixture portion (A), and the upper surface of the light mixture portion (B) is formed. pale mixture for flame holes (2) is formed, the light to the mixing section (B), the light of a light air-fuel mixture flowing toward the burner port (2) for the gas mixture the light mixing section to the ( B) width direction
Rectifying plate (14) is provided for rectifying and divided into direction, 且
The flame hole (2) for the light mixture is provided with the straightening plate (1).
4) A lean burn device formed by being divided in the width direction according to 4) , wherein the straightening plate (14) has an upper end having a flame for the rich mixture.
A light-to-dark combustion device provided so as to protrude above the hole (1) . 2. A plurality of flat rectangular tubular bodies (a) are housed in a bottomed rectangular tubular casing (K) in a state where they are arranged at intervals. And the light mixing section (A) is formed in a space surrounded by the adjacent rectangular cylindrical body (a) and the side wall (6) of the casing (K). 2. The light-and-dark combustion apparatus according to claim 1, wherein the flow straightening plate (14) is attached to the rectangular tubular body (a).