JP3177595B2 - 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 device used for a small-sized combustion device for home use or business use, and relates to a burner which suppresses generation of nitrogen oxides and the like.

[0002]

2. Description of the Related Art Combustion gas generated by combustion of burners used in various combustion apparatuses includes nitrogen oxides (N
O _X ). The NO _X is itself toxic to the human body, when released to the outside air is expected to be one of the causes generating the acid rain and photochemical smog. Therefore,
To reduce the generation amount of the NO _X, various countermeasures have been taken in the burner.

[0003]

The conventional countermeasure is for a large combustion device for industrial use or the like, which is legally regulated, and the burner for a combustion device for home use or small business use is a countermeasure. However, due to problems such as noise generation, it cannot be said that sufficient measures have been taken. In a large combustion device, the static pressure of the combustion fan can be increased, so that the flow of mixed gas or air as fuel can be easily controlled, the layout for the burner is high, and noise measures are easy. Moreover, no strict controlling condition against noise, etc., the combustion chamber can be made large, there is an advantage that it is easy to complete combustion be subjected to reduction measures of the NO _X by the so-called slow combustion. On the other hand, in a small-sized combustion device, the static pressure of the combustion fan is smaller than in a large-sized combustion device, it is difficult to control the flow of mixed gas and air, the layout is less flexible with respect to the burner, and noise countermeasures are difficult , and the strict controlling condition against noise, etc., the combustion chamber low, NO _X reduction measures are difficult.

Accordingly, an object of the present invention is to provide a combustion apparatus in which the generation of nitrogen oxides is suppressed by the combined combustion of a fuel-rich mixed gas and a fuel-lean mixed gas.

[0005]

The combustion apparatus according to the present invention is a combustion apparatus using a flame retention type premix burner, and includes first and second burner bodies (flame hole plate 7 or premix burner 1). Wherein the first burner body has a fuel-rich mixed gas having a high fuel amount to air amount ratio, and the second burner body has an air amount larger than the air amount and a fuel amount larger than the fuel amount. And supplying a fuel-lean mixed gas having a low ratio of the amount of fuel to the amount of air with respect to the amount of air, and burning the mixed gas by the first burner body and burning the mixed gas by the second burner body. Independently generated.

As shown in FIGS. 1 to 3, the combustion apparatus according to the present invention is a combustion apparatus using a flame retention type premix burner, wherein a single or multiple flame holes (2) are formed. a plurality of first burner body (premixed burner 1), wherein the first burner body by <br/> Ri Zenhonooana area is large second burner body while have a plurality of burner ports (6) ( Flame plate 7)
The flame hole surface of the second burner body is higher than the first burner body.
Protruding, and the second burner body and the second bar
And the first burner body disposed with the body in between.
And air passages (1) formed between the constituent units.
0), wherein the first burner body is supplied with a fuel-rich gas mixture having a high ratio of the fuel amount to the air amount, and the second burner body is supplied to the first burner body. The fuel-lean mixed gas is supplied by setting the air amount and the fuel amount larger than the air amount and the fuel amount to be performed, and setting the ratio of the fuel amount to the air amount to be low, and the first burner body Causing the combustion of the mixed gas and the combustion of the mixed gas by the second burner body to occur independently, and keeping the combustion flame of the second burner body by the combustion flame of the first burner body. Features.

In the combustion device of the present invention, the first burner body has a plurality of flame holes, and the second burner body has
The first burner body (premixed burner 1) is provided with a fuel-rich mixture, that is, a mixed gas, while having a plurality of burner holes and having a larger total burner area than the first burner body. The second burner body (flame perforated plate 7) is a fuel-lean mixed gas having a larger air amount and fuel amount than the first burner body side and a low fuel-to-air ratio. For combustion. Since the fuel-rich gas mixture is burned by the first burner body (premix burner 1) in a combustion region with a low oxygen partial pressure, the generation of NO _X is suppressed. The flame surface of the second burner body is the first burner.
Because it protrudes from the body, the flame of the second burner body
Flame stabilized by the flame of the first burner body below
Sex is enhanced. Also, a second burner body and a second bar
And a first burner body interposed therebetween.
And an air flow passage (10) formed between each structural unit.
The air is supplied from the
Temperature decreases, NOx is suppressed, and incomplete combustion
Can be prevented, and overheating of the burner can be prevented.

Further, the fuel-lean mixture gas is ejected above the second burner body (flame hole plate 7) and burns. Since this combustion is combustion of excess air, the excess air is cooled. Accordingly, the temperature of the flame (8) is maintained at a low temperature NO _X
Is suppressed. Although the combustion of the excess air alone has poor flame stability, the flame (4) of the first burner body (premix burner 1) acts as a pilot flame, and even if the combustion of the excess air occurs, the flame of the flame is not affected. Stability, that is, combustion stability is improved. Therefore, the lift of the flame (8) and the oscillating combustion do not occur, and the generation of noise is suppressed. Further, since the excess air acts to supply secondary air to the combustion of the first burner body, incomplete combustion in the combustion of the fuel-rich mixed gas can be prevented.

Further, in the combustion apparatus of the present invention, as illustrated in FIGS. 1 to 3, the top of the second burner body is attached to the first burner body.
Characterized in that it is projected Ri by the burner body. Such an arrangement, the combustion of the first and second burner body results in complement each other, the generation of the NO _X is suppressed, without causing the lift and oscillating combustion of the flame (8), Generation of noise can be suppressed, and incomplete combustion in the combustion of the fuel-rich mixed gas can be prevented.

[0010] In the combustion apparatus of the present invention, at least one pair of the first burner bodies is provided, and the second burner body is provided within an interval between the first burner bodies to form a structural unit. The unit is separated by providing a partition plate (9) for each constitutional unit, and providing an interval between each partition plate to form an air flow passage (1).
0). That is, between the first burner body (the premix burner 1 or the burner plate 7) to which the fuel-rich mixture gas having a high fuel ratio with respect to the air amount is supplied, the fuel having a low fuel ratio with respect to the air amount is provided. A second burner body (flame plate 7 or premix burner 1) to which a dilute mixed gas is supplied is provided. In this case, the fuel-rich gas mixture
The oxygen partial pressure in the combustion zone by a first burner member (premixed burner 1) is burned in a low state positioned on both sides of the second burner body (flame port plate 7), generation of the NO _X is suppressed Will be. Then, the fuel-lean mixture gas burns with the second burner body, and since this combustion is combustion of excess air, the flame (8)
Is maintained at a low temperature, and generation of NO _X is suppressed.
In the combustion of the excess air, since the combustion of the first burner body (premix burner 1) acts as a pilot flame, the stability of the flame is improved. It is as described above that the flame (8) is not lifted or vibrated, thereby suppressing the generation of noise. And the excess air is the flame of the first burner body (4).
The secondary air is supplied to the fuel cell, and incomplete combustion in the combustion of the fuel-rich mixed gas can be prevented. Also,
Since air is supplied by the air flow passage, overheating of the burner can be prevented while supplementing air necessary for combustion.

Further, in the combustion apparatus according to the present invention, as exemplified in FIGS. 1 to 3, the second burner body is provided within a space between the paired first burner bodies. . That is, between the first burner body (the premix burner 1 or the burner plate 7) to which the fuel-rich mixture gas having a high fuel ratio with respect to the air amount is supplied, the fuel having a low fuel ratio with respect to the air amount is provided. A second burner body (flame plate 7 or premix burner 1) to which a dilute mixed gas is supplied is provided. In this case, the fuel-rich mixed gas is burned by the first burner bodies (premix burners 1) located on both sides of the second burner body (flame hole plate 7) in a state where the oxygen partial pressure is low in the combustion zone. So
The generation of NO _X will be suppressed. Then, the fuel-lean mixed gas burns with the second burner body, and since this combustion is combustion of excess air, the temperature of the flame (8) is kept low by the cooling action of the excess air, and NO _X
Is suppressed. In the combustion of the excess air, since the combustion of the first burner body (premix burner 1) acts as a pilot flame, the flame stability is improved. It is as described above that the flame (8) is not lifted or vibrated, thereby suppressing the generation of noise. Then, the excess air supplies secondary air to the flame (4) of the first burner body, so that incomplete combustion in the combustion of the fuel-rich mixed gas can be prevented.

Further, the combustion apparatus of the present invention is characterized in that the first and second burner bodies independently form a flame above the first and second burner bodies, as exemplified in FIGS. If the flames are independently formed above, it is possible to prevent generation of local high-temperature portions in the overlapping portions of the flames and unstable combustion due to formation of a turbulent flow region.

Further, as shown in FIGS. 1 to 3, the combustion apparatus according to the present invention is characterized in that the second burner body includes a flame hole plate in which a number of slits are formed as flame holes. I do. This makes it possible to inject a fuel-rich gas mixture efficiently.

Further, the combustion apparatus of the present invention is characterized in that, as exemplified in FIGS. 1 to 3, the first or second burner body is constituted by a metal porous plate or a ceramic porous plate. The first or second burner body may be formed of a metal plate having a large number of slits formed as flame holes, or may be formed of a ceramic porous plate having a large number of appropriately formed flame holes.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 shows a first embodiment of the combustion apparatus of the present invention. For example, a flame retention type premixing burner 1 is used as a first burner body (or a second burner body) in the combustion apparatus. The premixing burner 1 includes a main flame hole 2 and a sleeve flame hole 3. And Flame 4
Are arranged on a straight line, the main flame hole 2 is a circular hole and is formed at the top of the burner main body, and the sleeve flame hole 3 is a circular hole smaller than the main flame hole 2 and extends from the top to the side surface side. It is arranged and formed on the formed inclined portion. Such an arrangement form,
By way of example, the premix burner 1 can have an appropriate configuration as long as it is a frame retention type.

In this combustion apparatus, a pair of premix burners 1 are arranged at a fixed interval, and an interval section 5 is provided as a means for maintaining the interval. Between the premix burners 1, for example, a burner plate 7 is provided as a second burner body (or a first burner body). , Protruding from the top of the premix burner 1. Therefore, the configuration is such that the mixed gas of the fuel gas and the air is supplied through the flame hole plate 7 and the interval portion 5. In this embodiment, the flame hole plate 7 is formed of a metal plate in which a number of long hole slits are formed as the flame holes 6, but the shapes of the flame hole plate 7 and the flame holes 6 are arbitrary, and the material is metal. Alternatively, ceramics or the like may be used. Flame hole 6
If it is configured to be separated from the premixing burner 1, the flames 4 and 8 are independently formed above the premixing burner 1 and the flame hole plate 7, so that it is possible to prevent the occurrence of overlapping portions of each flame. .

The method for supplying the mixed gas to the flame plate 7 and the method for mixing the fuel and air are the same as the methods for supplying and mixing the mixed gas to the premix burner 1. Can be. An air flow passage 10 is provided between the partition plate 9 and the premix burner 1.

The configuration of the combustion device shown in FIG. 1 can be configured as a single unit, or by arranging a plurality of units as a unit to form a combustion device having a desired combustion amount. be able to.

Next, FIG. 2 shows a second embodiment of the combustion apparatus of the present invention. In this combustion device, three premix burners 1 are arranged at intervals, and a flame hole plate 7 is provided at the interval 5 to supply a mixed gas of fuel gas and air. . According to such a configuration, the number of the perforated plates 7 formed by the premix burner 1 and each interval portion 5 is changed, so that a burner having a desired combustion amount proportional to the fuel amount of the premix burner 1 can be obtained. it can.
Also in this configuration, outside the premix burner 1,
A partition plate 9 is provided at intervals, and an air flow passage 10 is formed between the partition plate 9 and the premix burner 1. The air flow passage 10 may be provided as needed. Good.

In the above configuration, as described above, a fuel-rich mixed gas is supplied to the premix burner 1, and a fuel-lean mixed gas is supplied to the flame hole plate 7 to perform combustion. The fuel rich gas mixture above 1 is
Since the air supplied from the air flow passage 10 is burned as secondary air together with the excess air of the flame 8 above the flame hole plate 7, incomplete combustion in the combustion of the fuel-rich mixed gas can be prevented. It is. When the fuel-lean mixture gas is supplied to the premix burner 1 and the fuel-rich mixture gas is supplied to the flame hole plate 7 to perform combustion, supply of the secondary air from the air flow passage 10 is performed. There is no need for Therefore, in the case of configuring a combustion device that performs combustion by supplying such a mixed gas, the air flow passage 10 does not need to be provided.

Further, when a fuel-rich mixed gas is supplied to one of the premix burner 1 and the burner plate 7 and a fuel-lean mixed gas is supplied to the other side to perform rich / lean combustion, respectively. Assuming that the theoretical air amount is λ = 1, for example, λ is about 0.4 for a fuel-rich mixed gas and λ is about 1 for a fuel-lean mixed gas.
A mixed gas mixed to be 2 to 1.5 is supplied.

Accordingly, the fuel-rich mixed gas is supplied to one side of the premix burner 1 or the burner plate 7 for combustion, and the fuel-lean mixed gas is supplied to the other side to perform the lean-burn combustion. the by causing, it is possible to realize a combustion of the low NO _X with low noise, it is possible to compensate for the reduction in efficiency due to the combustion of the excess air.

Next, FIG. 3 shows an example of an implementation result of the combustion apparatus of the present invention. This experimental result shows that the fuel-rich mixed gas, premixed burner 1 was burned using the burner shown in FIG.
The graph shows a change in the NO _X emission amount with respect to the excess air ratio of the supplied mixed gas as a whole when the fuel-lean mixed gas is supplied to the burner plate 7 and burned. In this case, the supply amount of fuel in the mixed gas to the premix burner 1 and
The ratio of the supply amount of the fuel gas in the mixed gas to the flame plate 7 is
It is about 1: 2.

In the experimental results shown in FIG. 3, A represents the characteristics of the burner in the combustion apparatus shown in FIG. 1, and B represents the conventional burner. It can be seen that the combustion device of the present invention generates a very small amount of NO _X as compared with a conventional burner such as a Bunsen burner that is frequently used in a small combustion device.

[0026]

As described above, according to the present invention,
Combustion of fuel-rich gas mixture and large amounts of fuel and air
A fuel-lean mixture gas with a high air-to-fuel ratio
Fuel combustion, so that fuel-rich combustion
To supply surplus air from fuel-lean combustion.
The fuel-rich combustion is used as the fuel for fuel-lean combustion.
As a result, resulting in a rich fuel mixture.
NO from combustion of joint gas _XOf fuel generation and fuel leanness
NO from combustion of various mixed gases_XCoexist with reduced amount of
To improve the stability of the flame on the combustion side of the fuel-lean mixture.
To reduce noise and imperfect fuel rich gas mixture
Combustion can be prevented and NO can be reduced without increasing noise._Xof
A decrease in efficiency can be prevented together with the reduction.

[Brief description of the drawings]

FIG. 1 is a partial perspective view showing a first embodiment of a combustion device of the present invention.

FIG. 2 is a partial perspective view illustrating a second embodiment of the combustion apparatus of the present invention.

FIG. 3 is a graph showing NO _X emission characteristics as an experimental result of the combustion device shown in FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Premix burner (1st burner body or 2nd burner body) 4 Flame 6 Flame hole 7 Flame hole plate (2nd burner body or 1st burner body) 8 Flame 9 Partition plate 10 Air flow passage

Continued on the front page (72) Inventor Tatsuya Sugawara 2-11-2 Kajigaya, Takatsu-ku, Kawasaki City, Kanagawa Prefecture (72) Inventor Takao Takagi 201 Nishi-Kashiwara Shinda, Fuji City, Shizuoka Prefecture Takagi Sangyo Co., Ltd. (72) Invention Person Kimio Mochizuki 201 Nishi-Kashiwara Nitta, Fuji City, Shizuoka Prefecture Inside Takagi Sangyo Co., Ltd. (72) Inventor Shigetoshi Akiyama 201 Nishi Kashiwara Nitta, Fuji City, Shizuoka Prefecture Takagi Sangyo Co., Ltd. (56) References JP-A-1- 219406 (JP, A) JP-A-2-78813 (JP, A) JP-A-52-28322 (JP, A) JP-A-57-165908 (JP, U) JP-A-2-115627 (JP, U) Actually open Hei 2-85217 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F23D 14/02-14/10 F23C 11/00 329-330

Claims (7)

(57) [Claims] 1. A combustion apparatus using the frame retention type premixed burner, wherein while closed with a single or plurality of first burner body plurality of burner port is formed, a plurality of burner ports first and 1 of the burner body by Ri Zenhonooana larger area a second burner member flame hole surface of the second burner body than said first burner body
Protruding, and the second burner body and the second bar
And the first burner body disposed with the body in between.
An air passage formed between each of the constituent units, and a fuel-rich mixed gas having a high fuel amount to air amount ratio is supplied to the first burner body; The fuel-lean mixture is set in the burner body by setting the air amount and the fuel amount larger than the air amount and the fuel amount supplied to the first burner body and setting the ratio of the fuel amount to the air amount lower. Supplying a gas to cause the combustion of the mixed gas by the first burner body and the combustion of the mixed gas by the second burner body to occur independently, and to cause the combustion flame of the second burner body to A combustion apparatus characterized in that the flame is held by the combustion flame of the burner body (1). 2. A combustion apparatus according to claim 1, wherein the top portion of the second burner body is protruded Ri by said first burner body. 3. A plurality of pairs of said first burner bodies are provided, and said second burner body is provided within an interval between said first burner bodies to form a structural unit, and this structural unit is partitioned for each structural unit. 2. The combustion apparatus according to claim 1, wherein a plate is provided and separated, and a space is provided between the partition plates to form the air flow passage. 4. The combustion apparatus according to claim 1, wherein the first and second burners independently form a flame above the first and second burners. 5. The combustion apparatus according to claim 1, wherein the second burner body includes a flame hole plate in which a number of slits are formed as flame holes. 6. The combustion apparatus according to claim 1, wherein the first or second burner body is formed of a metal perforated plate. 7. The method according to claim 1, wherein the first or second burner body is formed of a porous ceramic plate.
Or the combustion device according to 3.