JPS62255710A - Combustion device - Google Patents

Abstract

PURPOSE:To reduce the generating amount of nitrogen oxides by a method wherein a burner head, provided with a plurality of primary flame ports at the side surface thereof, and a primary combustion chamber, covering the burner head and provided with secondary flame ports, are provided while a secondary air supplying passageway is provided in the burner head and the primary combustion chamber so as to penetrate them. CONSTITUTION:A burner head 18, provided with a plurality of primary flame ports 20 on the side surface thereof, is covered by a primary combustion chamber 22, provided with secondary flame ports 23 on the upper part thereof, while a secondary air supplying passageway 24 is provided in the burner head 18 and the primary combustion chamber 22 so as to penetrate them. Primary combustion in the primary combustion chamber 22 is effected in a degree higher than a combustible limit effected by the primary air principally and lower than the same effected by the logical amount of air. As a result, the generating amount of nitrogen oxides (NOx), especially that of nitrogen dioxide NO2, may be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to improving the combustion performance of a combustion device used for room heating, etc.

BACKGROUND OF THE INVENTION A conventional combustion apparatus of this type is shown in FIG. That is, a primary flame port part 2 having a plurality of primary flame ports 1 and a secondary flame port part 4 are provided in the upper part of the primary combustion chamber 3 that covers the primary flame port part 2,
The primary combustion within the primary combustion chamber 3 is caused by fuel supplied from the fuel nozzle 6 and primary air supplied from the primary air supply port 6 . Also, the secondary combustion is in the primary combustion chamber 3.
Unburned components remaining without being completely combusted within are supplied with secondary air at the secondary flame port 4 to form combustion. Furthermore, 7 is a premixing chamber, 8 is a secondary combustion surface, 9 is a burner caulking part, and 10 is a secondary flame opening throttle part. (For example, JP-A No. 5
Problems to be Solved by the Invention However, in the conventional configuration as described above, combustion is As the flame temperature decreases, the active groups generated by the primary combustion produce a reducing effect, reducing nitrogen oxides (NOx).
) had a tendency to decrease in the amount of porosity, but the amount was still large for use as a casserole for home heaters, and there was an upward trend in its actual use due to its toxicity. In addition, the active groups generated during primary combustion tend to reduce the total amount of nitrogen oxides (NoX);
is converted into nitrogen dioxide (fIJ02), which is considered to be more harmful, and the amount of nitrogen dioxide (N'02) generated tends to increase. It was seen as a problem.

The present invention has been made to solve these conventional problems, and an object of the present invention is to provide a stable charming apparatus that generates less nitrogen oxides (NOX), particularly nitrogen dioxide (NO2).

DESCRIPTION OF THE MEANS FOR SOLVING THE PROBLEMS In order to solve the problems, the apparatus of the present invention is as follows:
A burner head with a plurality of primary flame ports is installed in the kaji-hyaku, and a primary combustion chamber with a secondary flame port is installed in the upper part of the burner head, and a secondary air supply path is connected between the burner head and the primary combustion chamber. This is what I did.

For production The present invention uses the above-described configuration to achieve primary combustion.

Since it is divided into secondary and two-stage, the smoldering load is reduced and the combustion flame temperature is lowered. Also, at this time, since the secondary air supply passages in the fire combustion chamber and in the burner head are reversed in shape, the secondary air, the combustion gas in the combustion chamber, and the secondary air are connected through this secondary air supply passage. Heat exchange 81 is performed on the premixed gas (or raw gas) in the burner head. Therefore, the temperature of the secondary air increases significantly. On the other hand, the -Hokage burning chamber atmosphere temperature and combustion flame temperature are significantly lowered, and the premixed gas temperature is also lowered. This generally results in nitrogen oxides (NOx) produced during combustion, most of which are nitrogen oxides (NO).
However, the NO generation mechanism is called the Zeldovich mechanism and is expressed by equation (1), and the amount of NO generated is greatly affected by the temperature factor T.

For this reason, the amount of No and C generated during primary roasting is significantly suppressed by lowering the flame temperature during fire combustion.

This is also due to a decrease in the combustion rate in primary combustion due to a decrease in premixed gas temperature. In addition, since the temperature rise of the unburned components remaining in the flame combustion is also suppressed, the combustion speed in the secondary combustion is reduced, and the temperature rise of the secondary flame is suppressed.
Noxi generated in secondary combustion is also significantly reduced.

On the other hand, the production rate of carbon dioxide (NO2) is expressed by equation (2), and in a high temperature state, it is in the direction of NO production, and in a low temperature state, it is in the direction of NO2 production.

Dan Visitan - = k (No) (02) Song... (2) t Therefore, in order to suppress the conversion of NO generated by jjci into NO2, it is necessary to dilute it in a high temperature state and lower the temperature. is the best way. By the way, according to this configuration, the temperature of the secondary air has risen significantly, and the secondary combustion flame is not rapidly cooled, and in order to dilute the 9F gas with the secondary air in a high temperature state, it is converted to NO2. The conversion of N02 can be significantly suppressed, and the amount of N02 produced is significantly reduced.

EXAMPLE Hereinafter, an example of the present invention will be described based on the attached drawings. In FIG. 1, reference numeral 11 denotes a cylindrical bottomed vaporization chamber having a heater 12 for heating.A blower pipe 13 is connected to the side wall of this vaporization chamber 11, and one end opens into the vaporization chamber 11. , the other end communicates with the blower 14 to supply combustion air to the vaporization chamber 11.
supply within.

Further, the b-fuel is injected into the vaporization chamber 11 through a fuel nozzle 16 by a pump 15. The burner head 1 has a throttle-shaped premixture passage section 17 on the upper open surface of the vaporization chamber 11.
8 is placed. A burner cap 19 is provided on the upper open surface of the burner head and closes the upper opening. Further, a plurality of primary flame ports 20 are provided on the side surface of the burner head 18, and gold m21 is closely attached to the inner and outer surfaces thereof. Furthermore, the area around the burner head 18 is the primary combustion chamber 2.
2, a secondary flame outlet 23 is provided at the upper part of the Hokage burning chamber 22, and a pipe-shaped secondary air supply passage 24 is provided in the Hokage burning chamber 22 and the burner head 18 at approximately the center thereof. is installed through it.

In the above configuration, the primary air and fuel ejected from the feed nozzle 13 and the fuel nozzle 16 pass through the premixture passage section 17,
The premixed gas is supplied to the primary flame port 2o to form a -flame combustion flame 25. The primary combustion that is formed in the chamber 22 is mainly performed using primary air above the re-burning limit and below the theoretical air amount.
The unburned components that are not completely burnt inside are stored in the secondary flame port 23.
A secondary combustion fire 26 is formed by receiving the supply of secondary air. A part of this removed secondary air is supplied through the secondary air supply path 24, and therefore has a very high temperature. In this way, since the secondary air supply passage 24 is formed in the -hokage combustion chamber 22 and in the burner head 18, the secondary air and the primary combustion chamber 22 are exchanged via the secondary air supply passage 24. Heat exchange between the combustion gas, the secondary air and the premix in the burner head 18 becomes easier. Therefore, while the temperature of the secondary air rises significantly, the atmospheric temperature of the flame burning chamber 22 and the combustion flame temperature drop significantly, and the premixed gas temperature also drops. As a result, the amount of NO generated during primary combustion is greatly influenced by the flame temperature, so the amount of NO generated decreases significantly.Also, in oil combustion, the temperature of the premixed gas increases. However, the short arm speed tended to be faster.
By lowering the premixed gas temperature, there is no increase in the combustion rate, and the increase in flame temperature can be significantly suppressed. In addition, since the temperature rise of the unburned components remaining in the flame combustion is also suppressed, the combustion speed in the secondary combustion is reduced, the temperature rise of the secondary flame 26 is suppressed, and the Nox ( No)ffi also practices noticeably.

On the other hand, since the temperature of the secondary air has increased significantly in the secondary air supply path 24, the flame 26 in the secondary combustion is not cooled rapidly and locally, and the NO generated by combustion is converted into NO2. The amount of NOI produced is significantly improved, and the generation of toxic exhaust gases such as -carbon oxide (CO) can be suppressed, resulting in stable combustion.

Effects of the Invention As described above, the combustion apparatus of the present invention provides the following effects.

(1) Since the temperatures of the -fire combustion flame, secondary combustion flame, and the atmosphere thereof are reduced, the amount of nitrogen (NO) produced is significantly reduced, and the generation of nitrogen oxides (NOx) is significantly reduced.

(2) As the temperature of the secondary air increases, nitrogen monoxide (No) generated by combustion is hardly oxidized to nitrogen dioxide (NO2) under the influence of the secondary air, and nitrogen dioxide ( NO2) generation is significantly reduced.

(3) Since combustion is slow and no rapid combustion reaction occurs, combustion noise is significantly reduced.

(4) As the temperature of the secondary air increases, the flame becomes less susceptible to rapid cooling, and combustion becomes stable, resulting in -carbon oxide (CO
) and other toxic emissions can be suppressed.

(5) As the temperature of the premixed gas decreases, the combustion speed decreases, so flashback phenomenon during combustion becomes less likely to occur, and the stable combustion range expands.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of combustion Ek in one embodiment of the present invention, a perspective view of the second factor is the same, and FIG. 3 is a perspective view of a conventional combustion device. 1B...Burner head, 20...Primary flame port, 22...-Hokage burning chamber, 23...Secondary flame port, 24...・Secondary air supply path. Name of agent: Patent attorney Toshi Nakao, Baka 1, No. 2
figure

Claims (1)

[Claims] Consisting of a burner head having a plurality of primary flame ports on the side, a primary combustion chamber covering the burner head and having a secondary flame port at the top, and a secondary air supply passage penetrating through the burner head and the primary combustion chamber, The primary combustion within the primary combustion chamber is a combustion device that primarily uses primary air to burn the air above the flammability limit and below the theoretical air amount.