JP3226702B2 - Concentration combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a condition in which an enrichment flame for burning a rich air-fuel mixture is formed on one end surface, communicates with the enrichment flame, and is wider than a side edge of the burner body. A plurality of flat rich combustion burners formed with a rich mixing chamber formed by the above and a rich introducing section for guiding fuel gas and combustion air to the rich mixing chamber are formed in a rectangular cylindrical shape at intervals. A light mixing chamber, which is provided in the case and is provided on the same end surface as the rich combustion port for burning the light mixture, and a light mixing chamber communicating with the light combustion port, A flat light-burning section provided with a light-introducing section for guiding combustion air to the mixing chamber is formed between adjacent rich-burning burners, using the rich-burning burner as a constituent member. A lean gas supplier that supplies fuel gas to a lean gas passageway that guides the fuel gas or mixture for generation into the lean mixing chamber. A concentration gas supply means for supplying fuel gas to the concentration introduction section, and an air supply means for supplying combustion air to the concentration introduction section and the lean introduction section. .

[0002]

2. Description of the Related Art The above-described lean-burn combustion apparatus has a simplified structure by forming a lean-mixing chamber by utilizing a gap formed between the rich-burn burners juxtaposed in a rectangular cylindrical case. By stabilizing combustion of the rich mixture at the rich flame, the flame stabilizing action of the rich flame stabilizes the combustion at the lean flame and stabilizes the combustion as a whole. However, by lowering the combustion temperature, the amount of NO _x (nitrogen oxide) generated is reduced as much as possible.

In the above-structured lean-burn apparatus, the width of the lean-mixing chamber along the direction in which the rich-burn burners are arranged is wider at the side edges than at other portions, and the flow resistance is reduced. As a result, the supply amount of the light air-fuel mixture at the light flame outlet was unbalanced between the center and the end.

Therefore, conventionally, as shown in Japanese Patent Application No. 5-326624 filed by the present applicant, due to the imbalance in the supply amount of the lean air-fuel mixture, the end of the lean flame outlet is conventionally used. In order to avoid the generation of a flame larger than the center, a resistance plate is provided at the upper end where the flame port is formed to provide resistance to the flow of the air-fuel mixture at the edge.

[0005]

However, in the above-described conventional structure, although the discharge of the lean air-fuel mixture from the edge portion is prevented at the lean burn port where the air-fuel mixture burns, the lean air-fuel mixture is discharged from the lean air inlet. In the middle of the flow path of the lean mixture to the flame outlet, the flow resistance is large near the center, and the flow resistance is small at the edge, so that the unbalance of the flow amount of the lean mixture As a result, as a result, the flow amount becomes large in the region near the edge portion in the light flame outlet, and the problem that a larger flame is generated at the end portion than in the center portion is not sufficiently solved. And there was still room for improvement.

The present invention has been made in view of this point, and an object of the present invention is to provide a light-and-dark combustion apparatus capable of obtaining a good combustion state while simplifying the structure. is there.

[0007]

The features of the first invention are as follows.
An enrichment flame for burning a rich mixture is formed at one end surface, and communicates with the enrichment flame and is formed to be wider than the burner body side edge; A plurality of flat rich combustion burners formed with a rich introduction section for guiding the fuel gas and combustion air to the rich mixing chamber;
A light mixing chamber that is arranged in the rectangular cylindrical case and is provided on an end face on the same side as the rich combustion port for burning the light mixture, and a light mixing chamber that communicates with the light combustion port. A flat light-burning burner provided with a light-introducing portion for guiding combustion air to the light-mixing chamber is formed between adjacent rich-burning burners, using the rich-burning burner as a constituent member, A lean gas supply means for supplying a fuel gas to a lean gas passageway for introducing a lean gas mixture fuel gas or a mixture to the lean mixture chamber, and a rich gas supply means for supplying a fuel gas to the rich introduction section. Gas supply means, and an air supply means for supplying air for combustion to the rich introduction section and the lean introduction section, wherein in the lean mixing chamber, the rich combustion burner At the side edge and in the middle of the flow direction of the lean mixture, Lies in that the flow resistance element which imparts resistance to Les are provided.

[0008] The characteristic structure of the second invention specifies a structure suitable for carrying out the first invention, wherein the flow resistance member is provided with a plurality of the rich fuel burners along the direction in which the rich burners are arranged. The point is that it is formed in a state of being continuously connected over the combustion burner.

A feature of the third aspect of the present invention is to specify a configuration suitable for carrying out the second aspect of the present invention, wherein the flow resistance member is provided with respect to the rich combustion burner in a state of being mounted on the rectangular cylindrical case. The point is that the positioning portion is provided integrally.

A fourth aspect of the present invention specifies a configuration suitable for implementing any of the first to third aspects of the present invention, wherein the enrichment mixing chamber is one of a pair of side edge portions. And a flared portion extending from the end of the tubular conduit portion over substantially the entire width of the enrichment flame outlet.

[0011]

According to the characteristic structure of the first invention, the rich combustion burner, which is a constituent member of the lean mixing chamber, is a side edge portion having a narrow width, and is located at an intermediate portion in the flow direction of the lean mixture. In the position, by providing the flow resistance member, in the middle of the flow path of the lean mixture in which the combustion air and the fuel gas are mixed with the lean combustion burner supplied by the air supply means.
At the place where the rich combustion burner is formed narrow (the light mixing chamber is wide), resistance is given to the flow of the air-fuel mixture,
At this location, the flow of the air-fuel mixture is suppressed more preferentially than at other locations. As a result, the unevenness of the flow rate of the lean air-fuel mixture is suppressed, and the flow rate of the air-fuel mixture is substantially uniform in substantially the entire longitudinal direction of the flat lean-mixing chamber.

According to the characteristic configuration of the second invention, in addition to the operation of the characteristic configuration of the first invention, the flow resistance member is formed in a state of being continuously connected to a plurality of rich combustion burners, so that a plurality of flow resistance members are formed. As in the case of separately providing flow resistance members corresponding to each of the rich combustion burners, the flow amount can be reduced without complicating the structure such as increasing the number of parts or increasing the labor for assembling. Uniformization is possible.

According to the third aspect of the invention, in addition to the operation of the second aspect of the invention, the positioning portion of the rich combustion burner is provided integrally with the flow resistance member.
Furthermore, since the members can be shared, and the positioning portion of the rich combustion burner is connected in series, the interval between the rich combustion burners, that is, the width of each of the plurality of light mixing chambers is defined to be substantially the same width. Will be.

According to the characteristic structure of the fourth invention, the first invention to the first invention.
In addition to any of the functions of the third invention, there is the following function. In the enrichment mixing chamber, the fuel gas and the combustion air introduced from one side edge are connected to the cylindrical pipe portion extending toward the other side edge and to the cylindrical pipe portion. While passing through the long mixing path formed by the expanding portion, the mixing is sufficiently promoted, and the sufficiently mixed air-fuel mixture is supplied in a substantially uniform state along the longitudinal direction of the enrichment flame. Will be.

In addition, while the rich mixing chamber can ensure a sufficiently long mixing distance, the size of the light combustion burner along the flow direction of the combustion air can be reduced.

[0016]

According to the characteristic structure of the first invention, the lean mixing chamber is constituted by using the rich combustion burner as a constituent member. The unevenness of the flow rate is eliminated, the size of the flame can be made substantially uniform over almost the entire area of the leaning flame outlet, and a light and light combustion apparatus which can obtain a favorable combustion state in the light burning burner can be provided.

According to the second aspect of the present invention, in addition to the effect of the first aspect, the structure is complicated by forming the flow resistance member in a continuous state over a plurality of rich combustion burners. Thus, it is possible to provide a light-and-dark combustion apparatus that can make the above-mentioned flow amount uniform without requiring any additional work and without assembling.

According to the feature configuration of the third invention, in addition to the effect of the feature configuration of the second invention, the simplification of the structure and the improvement of the assemblability can be further achieved by the use of the members, and By setting the width of the mixing chamber to be substantially the same, the combustion state of each light-burning burner is homogenized.
A good combustion state can be achieved.

According to the fourth feature of the invention, the first to third features are provided.
In addition to the effects of the features of the present invention, the fuel gas and the combustion air are favorably mixed in the rich mixing chamber and the combustion state in the rich combustion burner is good even though the shape is compact. Can be something.

[0020]

Embodiments will be described below with reference to the drawings. FIG.
FIG. 3 to FIG. 3 show a concentration combustion device used for a hot water supply device or the like. Hereinafter, the configuration of the concentration combustion apparatus will be described.

A flat burner 3 for rich combustion is provided inside a box-shaped frame 2 (an example of a square tubular case) provided inside a burner case 1.
Are provided side by side at predetermined intervals, and below the box-shaped frame 2, at the bottom of the burner case 1, an air chamber 5 is formed as an air supply means, in which a discharge port 4 a of a combustion air supply fan 4 is opened. It is. By arranging the flat rich burners 3 side by side at predetermined intervals as described above, a configuration is made to function as a light burner 6 between the adjacent rich burners 3. Is used as a burner constituent member to form the light combustion burner 6 positioned between the adjacent rich combustion burners 3, thereby simplifying the entire apparatus configuration, and using the rich combustion burner 3 and the light combustion burner 6. Are alternately arranged in parallel to constitute a combustion device.

The rich combustion burner 3 includes a rich flame 7 for burning a rich air-fuel mixture having a small air rate, a rich mixing chamber 8 communicating with the rich flame 7, and a rich mixing chamber 8. A rich side inlet 9 for introducing combustion air for generating a rich mixture and fuel gas is formed, whereas a light burner 6 formed between the rich burners 3 has an air rate A light mixing port 11 for burning a light mixture having a large diameter, a light mixing chamber 11 communicating with the light mixing port 10, and a light introduction section 12 for introducing combustion air into the light mixing chamber 11. Configuration,
Combustion air is supplied from the air chamber 5 upward to the light introduction portion 12 through a ventilation plate 13 that forms the bottom wall of the box-shaped frame 2.

The lean gas passage 16 for introducing the mixture for producing the lean mixture and the lean side inlet 17 for introducing the fuel gas and the combustion air into the lean gas passage 16 are formed as described above. Each combustion burner is separated from the rich mixing chamber 8 and the rich side introduction port 9, and overlaps with the rich combustion burner 3 when viewed from the mixture discharge direction from the rich flame port 7. 3 are integrally formed. More specifically, the rich combustion burner 3 is formed by joining a pair of similarly bent and formed plate members, and is formed by bending and forming the rich mixing chamber 8, the rich side inlet 9, and the light gas passage. 16 and a light side introduction port 17 are respectively formed. Further, a plurality of the jet ports 18 for ejecting the fuel gas or the air-fuel mixture guided by the lean gas passage 16 are separately supplied to the lean mixing chambers 11 on both sides adjacent to the lean gas passage 16. In the state of being jetted out, the lightening gas passage 10 is formed in the lightening gas passage 16 by being dispersed in the longitudinal direction of the lightening flame opening 10.

In the figure, reference numeral 14 designates a concentration gas supply means for supplying the fuel gas supplied from the concentration gas supply passage 15 individually to the concentration side inlet 9 of each of the rich combustion burners 3. When the fuel gas is blown from the enrichment gas nozzle 14, the combustion air guided from the air chamber 5 is sucked into the enrichment side inlet 9 at a predetermined ratio by an ejector action. The rich mixture is mixed and generated in the process of passing through the use mixing chamber 8, and the rich mixture is burned at the use flame 7.

The enrichment mixing chamber 8 has the enrichment side introduction port 9 formed at one end in the longitudinal direction, a cylindrical pipe passage portion 8a extending laterally toward the other end, and a cylindrical pipe 8a. A fuel gas blown from the gas enrichment nozzle 14 from the end of the path portion 8a to an expansion portion 8c extending over substantially the entire width of the enrichment flame 7 via an arc-shaped bent portion 8b. The mixture is supplied to the enrichment flame port 7 in a state where the combustion air sucked by the ejector action and the fuel gas are sufficiently mixed with the stall inside the portion 8a.

Further, a lean gas nozzle 20 as lean gas supply means for supplying a fuel gas supplied from the lean gas supply passage 19 to the lean side inlet 17 of each of the lean burners 6 individually is provided. It is provided. That is, with respect to the lean air-fuel mixture, the combustion air guided from the air chamber 5 is introduced at a predetermined rate by the ejector action as the fuel gas is blown from the lean gas nozzle 20 into the lean side inlet 17. The mixture of the blown fuel gas and the intake air is mixed in advance in the conduction process in the lean gas passage 16, and the combustion air is supplied from the lean introduction section 12 through the inlet 17. Light mixing gas passage 1 for mixing chamber 11 for light mixing
6, the above-mentioned generated air-fuel mixture is ejected in a dispersed state from the plurality of jet ports 18 to mix and generate a light air-fuel mixture having a uniform mixed state in the light air mixing chamber 11, and It is configured to discharge from the mouth 10.

In the mixing chamber 11 for lean, the side edge of the rich combustion burner 3 opposite to the side inlet 9 for rich and at the middle of the flow direction of the lean mixture, specifically, At the position where the arc-shaped bent portion 8b of the rich mixing chamber 8 is formed, a flow resistance member 21 for providing resistance to the flow of the light mixture is provided. As shown in FIGS. 4 and 5, the flow resistance member 21 is formed in a state of being continuously connected to a plurality of rich combustion burners 3, and is rich burner mounted in the box-shaped frame 2. 3 are provided integrally with each other. More specifically, the flow resistance member 21 bends a plate material having a length substantially over the entire width in the direction in which the rich combustion burners 3 are juxtaposed into a U-shape, and places each bent portion corresponding to each rich combustion burner 3. Notched concave portions 23 and 24 into which the edge of the rich combustion burner 3 enters are formed. The bent portion of the cutout recesses 23 and 24 where the cutout recess 23 located on the upper side is formed constitutes the flow resistance member 21.

An engagement recess 25 is formed at the edge of the rich combustion burner 3 corresponding to the notch recess 24 located on the lower side. The engagement recess 25 engages with the notch recess 24. The rich combustion burner 3 is positioned in the lateral direction with respect to the box-shaped frame 2 and is positioned in the vertical direction to prevent the rich combustion burner 3 from coming off upward. Therefore, the positioning portion 2 is formed by the bent portion where the cutout recess 24 located on the lower side is formed.
2 are configured.

The upper side of the rich burner 3 is positioned in the lateral direction by a positioning portion 2a integrally formed with the box-shaped frame 2, and the positioning portion 2a closes the edge of the light flame port. The width of the light flame port 10 is defined to be substantially constant over the entire length in the longitudinal direction, so that good combustion can be performed.

By providing the flow resistance member 21 in this manner, the air-fuel mixture for the light-burning burner, which is blown upward and supplied in an equalized state via the perforated plate 13 for air conditioning, becomes a rich mixture. The unbalance of the flow amount in the longitudinal direction in the light mixing chamber 11 due to the intensive flow in the narrow portion A on the outer end side of the arc-shaped bent portion 8b forming the chamber 8 is prevented. It is configured to prevent it.

The combustion mode of the concentration combustion apparatus is as follows.
By burning the rich air-fuel mixture that enables stable combustion by itself by reducing the air ratio at the above-described rich flame opening 7, a light air-fuel mixture with a high air ratio discharged from the adjacent light flame opening 10 is formed. Thus, the combustion is stably continued by the flame holding action of the rich mixture combustion flame, thereby reducing the generation of NOx in the entire apparatus.

Each of the rich gas supply passage 15 and the lean gas supply passage 19 has both gas supply passages 15 and 1.
6 is provided with individual gas amount adjusting valves V1 and V2 for individually adjusting the fuel gas supply amount.
The main gas supply passage 21 upstream of the 19 branch point is provided with a main gas amount adjusting valve V3 for adjusting the total amount of the supplied fuel gas, so that the fuel gas supply amount as the whole of the concentration combustion device can be controlled. The adjustment (in other words, the input adjustment of the entire apparatus) is basically performed by the main gas amount adjustment valve V3, while the rich combustion burner 3 and the light combustion burner 6 are controlled.
The fuel gas ratio between the rich combustion side and the lean combustion side is adjusted so that the combustion in each of the above is maintained satisfactorily (that is, the fuel gas injection amount ratio between the rich gas nozzle 14 and the lean gas nozzle 20 is adjusted). Is performed using the individual gas amount adjusting valves V1 and V2 of the gas supply paths 15 and 19.

[Other Embodiments] (1) In the above embodiment, the fuel gas introduction portion for the rich combustion burner 3 is provided on one side, and the rich mixing chamber 8 is provided with a horizontal tubular pipe portion 8a. Arc-shaped bent portion 8b and expanded portion 8
c, but as shown in FIG. 6, the fuel gas introduction portion is provided on the lower side, that is, on the upstream side in the combustion air supply direction, and the tubular pipe portion 8a is formed vertically. Alternatively, the enrichment mixing chamber 8 may be formed so as to continue from the vertical tubular pipe portion 8a to the expanding portion 8c, and the flow resistance member 21 may be provided on one side edge of the expanding portion 8c. (2) In the above embodiment, the flow resistance member 21 is formed in a state of being continuously connected to the plurality of rich combustion burners 3.
As shown in FIG. 7, the respective rich combustion burners 3 may be separately provided in correspondence with each other. (3) In the above embodiment, the flow resistance member 21 is provided with the positioning portion 22 of the rich combustion burner 3 integrally.
The flow resistance member 21 and the positioning portion of the rich combustion burner 3 may be provided separately.

[0034] In the claims, reference numerals are provided to facilitate comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a concentration combustion device.

FIG. 2 is a cutaway perspective view of a concentration combustion device.

FIG. 3 is a vertical sectional side view of the concentration combustion device.

FIG. 4 is a plan view of a flow resistance member disposition portion.

FIG. 5 is a perspective view of a rich combustion burner.

FIG. 6 is a perspective view of a rich burner according to another embodiment.

FIG. 7 is a plan view of a flow resistance member disposing portion according to another embodiment.

[Explanation of symbols]

 2 Square-cylindrical case 3 Rich burner 4,5 Air supply means 6 Light burner 7 Rich flame opening 8 Rich mixing chamber 8a Cylindrical pipeline 8c Expanding part 9 Rich introduction section 10 Light flame 11 Light Mixing chamber 12 Light introduction section 16 Light gas passage 20 Light gas supply means 21 Flow resistance member 22 Positioning section

Continuation of the front page (56) References JP-A-5-231619 (JP, A) JP-A-5-164303 (JP, A) JP-A-6-117611 (JP, A) JP-A-7-180815 (JP) , A) JP-A-7-158823 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23D 14/08 F23D 14/70 F23C 11/00 329-330

Claims (4)

(57) [Claims] 1. A state in which an enriched flame port (7) for burning a rich mixture is formed on one end surface, communicates with the enriched flame port (7), and is wider than a burner body side edge. A flat rich combustion burner (3) formed with a rich mixing chamber (8) formed by the above and a rich introducing section (9) for guiding fuel gas and combustion air to the rich mixing chamber (8). ) Are arranged side by side in a rectangular tubular case (2) at intervals, and a light flame port (10) for burning a light air-fuel mixture is provided on an end surface on the same side as the thick flame port (7). A light mixing chamber (11) that is provided and communicates with the light flame port (10); and a light introduction part (12) that guides combustion air to the light mixing chamber (11). A flat lean burner (6) is formed between adjacent rich burners (3), using the rich burner (3) as a constituent member, to produce a lean mixture. A light gas supply means (20) for supplying a fuel gas to a light gas passageway (16) for guiding the fuel gas or air-fuel mixture to the light mixing chamber (11); Gas supply means (14) for supplying fuel gas to the fuel cell
And the dark introduction section (9) and the light introduction section (12).
A rich-burning apparatus provided with air supply means (4) and (5) for supplying combustion air to the burner (3), wherein the side of the rich-burning burner (3) in the lean mixing chamber (11). A rich-burn combustion apparatus, comprising a flow resistance member (21) for providing resistance to the flow of the lean air-fuel mixture at an edge and at a position in the middle of the flow direction of the lean air-fuel mixture. 2. The flow resistance member (21) is formed in a state of being continuously connected to a plurality of the rich combustion burners (3) along a direction in which the rich combustion burners (3) are arranged side by side. The concentration combustion device according to claim 1. 3. The flow resistance member (21) is integrally provided with a positioning portion (22) for the rich combustion burner (3) when mounted on the rectangular cylindrical case (2). The concentration combustion device according to claim 2. 4. The enrichment mixing chamber (8) includes: a tubular conduit portion (8a) extending from one of the pair of side edges toward the other; and a cylindrical conduit portion (8a). 4. The light-to-dark combustion apparatus according to claim 1, further comprising an expansion portion (8c) extending from an end portion over substantially the entire width of the enrichment opening (7).