JPH01155107A - Burner - Google Patents

Abstract

PURPOSE:To reduce the whole bottom area of a burner and compact the size of a combustion device, by forming a vessel headstand-shaped burner head of heat resistant and impact proof ceramics, vaporizing liquid fuel into gases, and discharging mixed gases of gas and air from a large number of flame ports provided on said wall surfaces. CONSTITUTION:A vaporized gas 9 of kerosene heat-gassified by a vaporizer 8 is ejected from a tip nozzle 8a and enters a mixing chamber 12 through a mixing pipe 11 together with a primary air 10a. The vaporized gas 9 and the primary air 10a are mixed inside the mixing chamber 12 so as to produce mixed gas. The mixed gas moves into a vessel headstand-shaped burner head 14 which is made of heat resistant and impact proof ceramics and fixed to the upper part of the mixing chamber 12 with stoppers 13. After it is further mixed in this chamber, the mixed gas passes through a large number of flame ports 15 formed on the sides of the burner head 14 and forms primary combustion flames 16 on the side surface of the burnerhead 14. Then, the combustion reaction is completed by the surrounding secondary air 10b through secondary combustion flames.

Description

DETAILED DESCRIPTION OF THE INVENTION [Prior Art] Burners for combustion equipment that burn liquid fuel can be broadly classified into spray type and evaporation type. The spray type is a method in which liquid fuel is atomized into a large number of small-diameter droplets and then combusted, and is mainly used for heavy fuels, and the combustion load rate is relatively low. On the other hand, the evaporative type evaporates liquid fuel at high temperatures, mixes it with air, and burns it, and is mainly used for light fuels. This evaporative type has a high combustion negative 6:f ratio and has the advantage of being less likely to generate soot.

Conventionally, as this evaporation type combustion equipment, there is a petroleum (kerosene) forced evaporation combustion type combustion equipment having a burner structure as shown in FIG. The burner of this device is installed so that the jet nozzle 3 of the vaporizer 1 is inserted into a side opening of a mixing chamber 2 made of metal, and the vaporizer 1 heats and vaporizes kerosene. Further, a plurality of rectifying membranes 4 are provided inside the mixing chamber 2, and a burner head 5 made of a metal wire mesh is bonded to the upper surface of the mixing chamber 2. Further, a combustion cylinder 6 is provided in the upper part of the mixing chamber 2 so as to cover the burner head 5.

In the combustion operation of this burner, first, kerosene (hereinafter referred to as vaporized gas) vaporized by the vaporizer 1 is ejected from the ejection nozzle 3 into the mixing chamber 2 . At the same time, outside air is also drawn into the mixing chamber 2, mixed with the vaporized gas in the mixing chamber 2, passed through the rectifying membrane 4, moved upward, and further passed through the wire mesh of the burner head 5 and ejected. Then, this mixed gas is ignited and burned on the upper surface of the burner head 5.

[Problems to be Solved by the Invention] As described above, in the burner of the conventional combustion device, the burner head 5 is composed of a metal wire mesh.

This caused the following problems.

(1) Since the burner head is made of wire mesh, the distance between the flame holes corresponding to the mesh of this wire mesh is very small. Therefore, the primary combustion flames formed on each flame hole overlap each other, increasing the flame length of the entire burner head, thereby increasing the generation of NOx (nitrogen oxides).

(2) Because the wire mesh is made of metal, its thermal emissivity is low.
In addition, since it is a wire mesh, the porosity is high and the heat capacity is small.

Therefore, the temperature of the combustion surface (wire gauze surface) of the burner head becomes too high, which further promotes an increase in NOx in addition to the above-mentioned item (1).

(3) Because the burner head is made of metal, high-temperature thermal deformation occurs during combustion. Therefore, the burner head is restricted to a shape that can absorb thermal deformation, for example, a flat shape. For this reason, the shape of the burner is limited, making it difficult to make the structure compact.

Therefore, the present invention is structurally compact and NO.
An object of the present invention is to provide a combustion device that generates less x.

[Means for Solving the Problems] The combustion device of the present invention includes a vaporizer that vaporizes liquid fuel to generate gas, a mixing chamber that mixes the gas and air to produce a mixed gas, and a mixing chamber that produces a mixed gas. This combustion device includes a burner head that ejects flames from a large number of flame holes formed in the wall surface and burns the flames on the wall surface, and the burner head is characterized by being made of thermal shock-resistant ceramic.

Furthermore, in one embodiment of the present invention, the shape of the burner head is
The container has an inverted shape so that the combustion surface of the burner head faces almost vertically.

[Function] In the combustion device of the present invention, the burner head is made of thermal shock-resistant ceramic. Therefore, thermal deformation due to high temperatures during combustion does not occur. Therefore, the combustion surface of the burner head can be formed wide and the distance between the flame holes can be increased. This prevents the primary combustion flames from overlapping each other and shortens the flame length over the entire combustion surface. Furthermore, the temperature of the combustion surface can be lowered due to the good thermal bk emissivity, which is a characteristic of ceramic materials. These effects can reduce the generation of NOx.

Furthermore, since there is no problem with thermal deformation as described above, there are no restrictions on the shape of the burner head. For example, in one embodiment of the present invention, the burner head has an inverted vessel structure, and the combustion surface is formed on the almost vertical wall surface, thereby widening the combustion surface and reducing the bottom area of the entire burner. We are trying to make it more compact.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a cross-sectional structural diagram of a burner of a combustion apparatus according to the present invention. Kerosene vaporized gas 9 heated and vaporized in the vaporizer 8 is injected from the tip nozzle 8a, and enters the mixing chamber 12 through the mixing pipe 11 together with the primary air 10a. The vaporized gas and the primary air 10a are mixed in the mixing chamber 12 to form a mixed gas, and a burner head 1 in the shape of an inverted container made of thermal shock-resistant ceramic is fixed to the upper part of the mixing chamber 12 with a fitting 13.
Move inside 4. After being further mixed therein, the mixture passes through a large number of flame holes 15 formed on the side surface of the burner head 14, and forms a primary combustion flame 16 on the side surface of the burner head 14. After that, the surrounding 2
The combustion reaction is completed by the next air 10b.

The burner according to the present invention as shown in the above embodiments provides the following effects.

First, since the burner head 14 of the present invention is made of thermal shock-resistant ceramic and has an inverted vessel structure, NOx during combustion is reduced for the following reasons.

(1) Ceramic with good thermal emissivity is used as the burner head material, which reduces the temperature of the combustion surface.

(2) Due to the inverted container structure, the combustion surface is wide, which reduces the combustion load rate per unit area.
The temperature of the combustion surface decreases.

(3) The combustion surface becomes wider and the distance between the flame holes becomes longer, so the primary combustion flames no longer overlap.

Therefore, the length of the entire flame 17 becomes shorter.

Further, as described above, in the present invention, the burner head 14 has an inverted vessel structure, and the combustion surface is formed in a substantially vertical direction, so that the bottom area of the burner can be reduced.

Furthermore, as described in item (3) above, the entire flame 17
Since the length of the combustion tube 18 is shortened, the combustion tube 18 can also be shortened. Therefore, the overall shape of the burner can be made compact.

Furthermore, since ceramic is used as the material for the burner head, the harsh high-frequency range of combustion noise generated during combustion is muffled. In addition, the burner head has an inverted container structure, and the mixed gas is mixed even more well within the burner head, resulting in stable combustion.
It is also effective in reducing (-carbon oxide). In addition, since the container is an inverted type with a large combustion area, the heat radiation effect is large, and the visual effect as a heater is large, significantly improving the marketability.

As the type of ceramic material for the burner head of the combustion device of the present invention, cordierite ceramics having good thermal shock resistance or lithium ceramics containing β-spodumene as a main component are suitable. However, it is not limited to this.

Here, burner head 1 made of thermal shock resistant ceramic
An example of the manufacturing process of No. 4 is shown in FIG. burner head 14
is mainly manufactured through a ceramic material mixing process, a burner head molding process, a flame hole opening process, and a drying and firing process. For drilling holes, for example, if the burner head is cylindrical or conical, a drill machine may be used; if the burner head is polygonal, a punching machine may be used. In addition, the firing process is usually 1450℃ for cordierite type and 1260℃ for lithia type.
It will be held in

Furthermore, the shape of the burner head of the combustion device of the present invention may be a conical shape, a cylindrical shape, a polygonal pyramid shape, a polygonal column shape, etc. as an inverted container type, but is not limited to these shapes. It can also be something.

[Effects of the Invention] As described above, in the combustion device according to the present invention, since the nozzle head is formed using a thermal shock resistant ceramic material,
It is possible to reduce the generation of NOx caused by combustion surface temperature and the like. Furthermore, in the embodiment of the present invention, the burner head is formed into an inverted container type, and a combustion surface is provided on the side surface of the burner head. This makes it possible to reduce the size of the combustion device, reduce the generation of NOx and CO during combustion, and realize a combustion device with low noise and high visual effects.

[Brief explanation of the drawing]

FIG. 1 shows a cross section 11 of a combustion device according to an embodiment of the present invention.
■It is a drawing. FIG. 2 is a manufacturing process diagram of a burner head of a combustion device according to an embodiment of the present invention. FIG. 3 is a cross-sectional structural diagram of a conventional combustion device. In the figure, 8 is a vaporizer, 12 is a mixing chamber, 14 is a burner head, and 15 is a flame hole of the burner head.

Claims (1)

[Claims] A vaporizer that vaporizes liquid fuel to generate gas; a mixing chamber that mixes the gas and air to produce a mixed gas; and a mixing chamber that ejects the mixed gas from a number of flame holes formed in the wall thereof. and a burner head for causing combustion on the wall surface of the burner head, characterized in that the burner head is made of a thermal shock resistant ceramic.