JPH042846B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a burner device suitable for burning flame-retardant fuel such as fine coke.

With recent changes in the fuel situation, it has become possible to reduce power generation costs by converting the fuel used in large boilers from petroleum (for example, heavy oil) to petroleum coke, which is an inexpensive fuel that retains the structure of petroleum boilers. Ta. However, such combustion of petroleum coke has been extremely difficult to achieve in terms of ignitability and flame retention. In order to realize this, the inventors and others
After conducting various experiments, we were able to develop a burner suitable for burning petroleum coke. The structure was previously filed in Utility Application No. 162051/1983. In this case, the petroleum coke is pulverized in advance into fine particles of a predetermined particle size and transported by pneumatic flow to the burner. In addition, petroleum coke has a high fuel ratio (fixed carbon/volatile content) of 7 to 9.5, making it difficult to ignite and hold the flame. Therefore, a flame with good ignition and flame holding properties, such as a heavy oil flame, is formed in the center of the pulverulent coke burner. However, we adopted a method that completely burns fine coke.

FIG. 1 shows an example of a burner used in experiments by the inventors, which burns fine coke. First, when starting the burner, the ignition torch 5 ignites the heavy oil injected from the heavy oil burner 4 and causes it to burn. On the other hand, petroleum coke pulverized by a pulverizer (not shown) is transported by air flow to the elbow 9,
The fine coke is injected into the furnace 7 through the burner 2,
When it comes into contact with the heavy oil flame 14, it ignites and forms a pulverized petroleum coke flame 15. In the figure, reference numeral 3 represents an impeller, 13 represents secondary air, and 12 represents tertiary air.

FIGS. 2 and 3 are diagrams showing how the heavy oil flame 14 and the pulverized petroleum coke flame 15 are formed, and the pulverized petroleum coke flame 15 is formed to surround the heavy oil flame 14, which is the auxiliary fuel. .
In this type of burner, the fine coke is ignited and burned mainly by the radiation of the heavy oil flame 14, but the heavy oil flame 14 consumes oxygen by the fine coke flame 15, and the air with a low O ₂ partial pressure Combustion will be carried out by As a result, the heavy oil flame temperature is relatively low, resulting in situations such as a longer coke combustion time and an increased amount of unburned matter.

An object of the present invention is to provide a burner device that eliminates the above-mentioned problems and has high combustion efficiency and can reduce the amount of unburned matter generated.

In short, the present invention has a means for turning the ejected flow of the flame-retardant pulverized fuel into a swirling flow, and forms a auxiliary combustion nozzle set by arranging a plurality of nozzles at biased positions, so as to divide the sprayed flow of the flame-retardant pulverized fuel. This burner device for flame-retardant fuel is characterized in that a plurality of auxiliary combustion nozzle sets are arranged at a distance from each other.

Embodiments of the present invention will be described below with reference to the drawings.

4 to 6 show a first embodiment of the invention. In the figure, inside the pulverulent coke burner 2, a heavy oil burner 4 for injecting heavy oil as auxiliary fuel is arranged so that the central axes thereof are substantially the same. At the tip of the heavy oil burner 4, three burner nozzles 20 are arranged in two groups. As a result, the heavy oil injected from the heavy oil burner 4 is divided into two groups and injected, forming heavy oil flames 14a and 14b.
On the other hand, the pulverized petroleum coke is given a swirling force by the swirler 21 at the outlet of the pulverized coke burner 2, and is injected into the furnace to form a pulverized coke flame 15. Since the fine coke itself is given a swirling force, the divided flames 14a, 14 as shown in FIG.
b, and makes full contact with these flames. For this reason, fine coke ignites and burns in a short time, improving combustibility and reducing the rate of unburned matter. In other words, by creating a split flame, the chances of contact between the heavy oil flame and the fine coke increase, and the flame surface area increases, and even the fine coke that does not come into direct contact with the heavy oil flame can be ignited and burned in an extremely short time due to strong radiant heat.

7 and 8 show another embodiment.

Reference numeral 22 indicates gaseous fuel (LNG,
This is a gas burner that injects LPG, etc.), and as shown in Figure 8, it is a gas burner that injects
Divide the books into two groups and place them facing each other. For each gas burner, for example, two nozzles that eject gas in the radial direction from the axis of the nozzle management material are formed, and the nozzle formation positions are determined so that the flame 23 of each gas burner as a whole turns in the same direction. I'll keep it. As a result, the fine coke injected from the fine coke burner 2 mixes well with the gas burner flame 23 and ignites and burns in a short time. In this case, a swirler may be arranged in the fine coke burner 2 to apply swirling force to the fine coke itself. Further, the fuel of this burner 22 may be changed to liquid fuel such as heavy oil as in the first embodiment, or conversely, the burner shown in FIG. 4 may be used as a gaseous fuel burner.

By carrying out this invention, the flame caused by the auxiliary fuel is divided into a plurality of parts, so that the flame retardant fuel such as petroleum coke and the auxiliary fuel flame come into sufficient contact, and the flame resistant fuel ignites and burns in a short time. The amount of unburned matter generated can be significantly reduced, and the controllability of the burner can be improved.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a fine coke burner, which is an example of a burner used in the inventors' experiments, and Figure 2 is a cross-sectional view of a fine coke burner.
3 is a sectional view taken along the - line in FIG. 2, FIG. 4 is a sectional view of the fuel injection part of a burner device according to an embodiment of the present invention, and FIG. FIG. 4 is a front view of the heavy oil burner taken along the - line in FIG. 4, FIG. 6 is a sectional view taken along the - line in FIG. FIG. 7 is a sectional view taken along the - line in FIG. 7; 2...Fine powder coke burner, 4...Heavy oil burner, 14a, 14b, 23... Fuel split flame for auxiliary combustion, 20...Heavy oil burner nozzle, 22... Gas burner.

Claims (1)

[Scope of Claims] 1. It has a means for turning the ejected flow of the flame-retardant pulverized fuel into a swirling flow, and forms an auxiliary combustion nozzle set by arranging a plurality of nozzles in uneven positions to divide the sprayed flow of the flame-retardant pulverized fuel. A burner device for flame-retardant fuel, characterized in that a plurality of auxiliary combustion nozzle sets are arranged at a distance from each other. 2. The nozzles are a plurality of nozzles that eject auxiliary combustion fuel in a radial direction from the axis of the nozzle tube member, and a plurality of the nozzle tube members are arranged in parallel and offset to form one auxiliary combustion nozzle set, and the auxiliary combustion A burner device for flame-retardant fuel according to claim 1, characterized in that the nozzle sets are arranged at a distance from each other. 3. The burner device for flame-retardant fuel according to claim 2, wherein the auxiliary combustion nozzle set is a auxiliary combustion nozzle set for gas combustion.