JPH07243622A - Gas burner of combustor - Google Patents

Abstract

PURPOSE:To provide a burner which allows the diameter of a throttle hole, i.e., a passageway for flame-holding gas, to be greater than the limiting diameter against choking and effects the combustion in a stabilized state without involving choking of the nozzle hole or an unbalance in the circular spread of the ejected gas. CONSTITUTION:Inside a manifold 14 a flame-holding gas chamber 13 it provided adjacently to a gas chamber 2. The flame-holding gas chamber 13 and the gas chamber 2 are connected by throttle holes. Flame-holding fuel gas is fed from the flame-holding gas chamber 13 toward the flame-holding gas nozzle holes of a plurality of fuel nozzles 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a gas burner device of a combustor used for burning a gas fuel, for example, a gas combustion boiler, a gas turbine combustor, a gas combustion furnace or a gas combustion instrument. Is.

[0002]

2. Description of the Related Art A gas burner of this type which has been generally adopted in the past has a plurality of burner caps in order to improve the stability of the burner flame, as described in, for example, Japanese Patent Laid-Open No. 50-2221. An individual main fuel (gas) injection port is provided, and a plurality of surrounding openings (in the invention, the opening 4
4) is provided, and the combustion air is premixed in the flange portion installed around the burner.

A small opening area is sufficient for the plurality of peripheral openings (openings 44) if the flame holding performance of the flange is good. In particular, in reducing the nitrogen compound (NOx) by combustion, which has been increasingly demanded in recent years, it is preferable that the flame holding gas amount is small.

Therefore, in order to reduce the nitrogen compound (NOx), the number of a plurality of peripheral openings is reduced,
Further, it is required to reduce the opening diameter. Especially in a combustor with excessive combustion air, the fuel supplied from the main gas injection port is mixed in advance. The gas fuel for flame holding supplied from the individual peripheral openings is required to be further reduced from the viewpoint of reducing NOx.

[0005]

In the burner device thus formed, as can be seen from FIGS. 5, 6 and 7 of the above publication, the proportion of the area of the flame holding gas injection port (opening 44) is large. Large (6 for every 22 nozzles), and with the same nozzle diameter, 27.2% of the fuel becomes gas fuel for flame holding. Therefore, for this reason, the proportion of NOx generated by the flame-holding gas fuel is large, and as a result, it is difficult to significantly reduce NOx.

Further, in the case of such a burner device, for example, in the case of a small-capacity gas burner, the flame holding gas injection port area is relatively reduced, but the flame holding gas injection port area is reduced. There is a risk that the fuel nozzles will be clogged, and it is not possible to reduce the diameter in a random manner.

Therefore, in such a case, the number of nozzles is reduced, but conversely, reducing the number of nozzles causes an increase in the distance between the nozzles and an imbalance in the gas ejection in the entire circumferential direction. As a result, the flow rate of the flame holding gas fuel is limited, and it becomes difficult to expect stable combustion.

As described above, in the conventional gas burner device, from the viewpoint of reducing NOx, the combustion failure will occur if the number of gas injection holes is reduced in order to reduce the combustion on the flame holding burner side or the area of the flame holding gas flow passage is reduced. Stability and clogging of the burner occurred, and it was difficult to achieve stable combustion while reducing NOx.

The present invention has been made in view of the above, and an object thereof is to make the diameter of the flame-holding gas flow passage larger than the clogging limit diameter, in other words, the gas of the flame-holding nozzle. It is an object of the present invention to provide a gas burner device of this type in which the flow passage is not clogged and the imbalance in the gas ejection in the circumferential direction does not occur.

[0010]

That is, according to the present invention, a flame holding gas chamber is provided inside a manifold adjacent to a gas chamber, and the flame holding gas chamber and the gas chamber are connected by a throttle hole, and The flame holding fuel gas is supplied from the flame holding gas chamber to the flame holding gas nozzles of the plurality of fuel nozzles to achieve the intended purpose.

[0011]

In other words, with the gas burner device formed in this way, even if the flame-holding gas fuel flow rate is reduced to reduce NOx, the flame-holding gas chambers hold the flame-holding gas injection holes of a plurality of fuel nozzles. Since the flame fuel gas is supplied, that is, it serves as a common throttle hole, the diameter of the throttle hole becomes large to some extent and it is possible to ensure that it exceeds the clogging limit. Without causing
Moreover, since the required number of flame-holding gas injection holes is maintained, the jetting of gas in the circumferential direction is balanced and stable combustion is performed.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows an embodiment of the gas burner device in cross section.

In the gas burner device, a head plate 9 having a fuel nozzle 15 for injecting fuel into the combustion chamber 8 and a supply port 7 for combustion air is provided upstream of the combustor wall 12 forming the combustion chamber 8. Gas fuel supplied from the fuel nozzle 15 and combustion air supplied from the supply port 7 are provided in the combustion chamber 8
It is formed to burn inside.

A plurality of fuel nozzles 15 are connected to the gas manifold 14 and are provided. The gas manifold 14 is formed in a hollow ring shape, the hollow portion forms a gas chamber 2, and the fuel nozzles are provided in communication with the gas chamber 2 at predetermined intervals in the circumferential direction. There is.

The gas fuel 1 is first supplied from an external gas supply source (not shown) to the gas chamber 2 arranged on the base side of the fuel nozzle, and is distributed to each fuel nozzle 15 from this gas chamber. Then, it flows through the fuel flow passage in the nozzle, is supplied into the combustion chamber 8 as the main gas jet 4 from the main injection port provided in the nozzle head 17, and is burned.

On the other hand, the combustion air 5 enters from the left side of the figure and the air flow 6
Is supplied from the air supply port 7 to the combustion chamber 8 to cause the main gas jet 4 to burn.

In addition to the gas chamber 2, the gas manifold 14 is provided with one or more flame holding gas chambers 13. Between the gas chamber 2 and the flame-holding gas chamber 13, one or a plurality of flame-holding gas throttle holes 20 are provided as described later to regulate the flame-holding gas fuel flow rate.

A flame stabilizer 16 is provided at the tip of each fuel nozzle 15.
Is provided, and a stable flame is formed by the vortex of the wake of the flame stabilizer 16 which is supplied to the wake of the flame stabilizer 16 through the passage independent of the main gas passage 3 and is generated by the air flow 6. Let

A head plate 9 for separating the combustion chamber 8 from the upstream air passage is arranged at the head of the combustion chamber 8.
Then, combustion air is taken into the combustion chamber 8 through a plurality of air supply ports 7 provided in the head plate 9. In addition to the air supply port 7 of the nozzle penetrating portion, an air intake hole 7a can be optionally provided on the head plate 9 to ensure a good combustion state, for example, low NOx combustion, complete combustion state.

A spark plug 10 is provided in the combustion chamber 8 and is ignited by a discharge spark 11. The spark plug 10 is formed so as to move to the outside of the combustor wall 12 by an actuator (not shown) after ignition, so that the spark plug 10 is prevented from burning.

FIG. 2 is a cross-sectional view of the gas manifold 14 section. In this case, four flame holding gas chambers 13 are provided. When the flame holding gas chamber 13 has one or a plurality of holes along the entire circumference and the hole diameter of the flame holding gas throttle hole 20 is increased,
The number of flame holding gas chambers 13 may be reduced. In other words, the amount of flame holding gas required for one fuel nozzle 15 is determined by the combustion device. Therefore, if two fuel nozzles 15 are shared, the area of the flame holding gas throttle hole 20 should be doubled. Is possible. That is, if the four fuel nozzles 15 are shared in the same manner, the area of the flame holding gas throttle hole 20 becomes four times.

By forming in this way, the area of the flame holding gas throttle hole 20 can be increased, and the probability of clogging of the flame holding gas throttle hole 20 can be reduced.

FIG. 3 is a front view of the gas manifold 14 and the fuel nozzle 15, showing an air supply port 7 provided on the head plate 9 and a flame stabilizer 16 inserted in the air supply port 7. The nozzle head 17 provided at the tip of the flame stabilizer 16 can be seen. As described above, the head plate 9 may be provided with the air supply holes scattered in addition to the air supply holes 7 which also serve as the through holes of the fuel nozzle, but it is not particularly shown here.

FIG. 4 shows a detailed cross section of a plurality of fuel nozzles 15 provided in the gas manifold 14. The main fuel gas is provided in the nozzle head 17 from the gas chamber 2 through the main gas flow passage 3. It is injected into the combustion chamber 8 from the main gas injection port 25.

On the other hand, the flame-holding gas fuel is taken into the flame-holding gas chamber 13 through the flame-holding gas throttle hole 20 and is held in a ring shape from the flame-holding gas inlet 21 provided in the fuel nozzle 15. An appropriate amount of flow resistance is imparted by the flame holding gas resistance portion 23 through the flame gas passage 22, flows through the flame holding gas passage 24, and is supplied from the flame holding gas injection port 26 to the downstream portion of the flame stabilizer 16.

In this case, the nozzle outer wall 27 and the nozzle inner wall 2
Although the flame holding gas passage is formed between 8
This flame-holding gas passage does not necessarily have to be annular. For example, it does not matter if the flame-holding gas resistance portion 23 is also used as a spiral groove (one line or multiple lines).

FIG. 5 shows a cross section of the fuel nozzle, which is constructed by providing four flame holding gas narrow passages 29 on the nozzle inner wall 28 and combining them with the nozzle outer wall 27. In this case, the flame holding gas narrow portion passage 29 may be linearly provided on the axis of the nozzle inner wall 28, or may be provided in a spiral shape (spiral shape).

Further, the flame holding gas narrow portion passage 29 may be provided on the nozzle outer wall 27 side. The point is that the flame-holding gas narrow portion passage 29 may be formed between the nozzle outer wall 27 and the nozzle inner wall 28 or in the nozzle itself,
Various ways of forming the passage may be considered.

FIG. 6 is a sectional view showing the flame holding gas jetting portion of the fuel nozzle. The flame holding device 16 is provided from the flame holding gas passage 24 through a plurality of flame holding gas nozzles 26 (8 nozzles are shown in the figure). Flame holding gas fuel is supplied to the rear part. The flame is firmly fixed on the flame stabilizer 16 by the vortex formed in the wake of the flame stabilizer 16.

FIG. 7 is a cross-sectional view of the flame-holding gas chamber 13, in which the flame-holding gas fuel supplied from the gas chamber 2 is passed through the flame-holding gas throttle hole 20 and the flame-holding gas chamber. 13 is supplied. In this case, a window 30a and a blind plate 30 are provided on the wall surface of the manifold facing the throttle hole 20.

By providing the window and blind plate 30 in this manner, the throttle hole 20 can be inspected, and even if the flame holding gas throttle hole 20 is clogged, cleaning can be performed. . Further, the window and blind plate 30 may be provided on the wall on the gas chamber 2 side.

As described above, the first effect of the present invention is
In order to achieve low NOx gas combustion, it is necessary to reduce the amount of flame holding gas fuel as much as possible, but gas manifold 1
By providing the flame-holding gas chamber 13 in 4 to share the flame-holding gas fuel of the fuel nozzle, the clogging trouble can be eliminated.

The second effect of the present invention is that since a proper flow resistance is given to the flame holding gas passage of each fuel nozzle, the flame holding gas is evenly distributed from the flame holding gas chamber 13 to each fuel nozzle 15. Fuel is distributed.

Further, the third effect of the present invention is to eliminate clogging trouble by providing a removable blind plate so that cleaning can be performed even if the flame holding gas throttle hole 20 is clogged. It is possible.

[0035]

As described above, according to the present invention, the flame holding gas chamber is provided inside the manifold adjacent to the gas chamber, and the flame holding gas chamber and the gas chamber are connected by the throttle hole. Moreover, since the flame-holding fuel gas is supplied from the flame-holding gas chamber to the flame-holding gas nozzles of the plurality of fuel nozzles,
Since the flame-holding fuel gas is supplied from the flame-holding gas chamber to the flame-holding gas nozzles of the plurality of fuel nozzles, the diameter of the throttle hole becomes large to some extent and can be secured beyond the clogging limit.
Therefore, it is possible to obtain this kind of gas burner device in which the gas flow passage of the flame holding nozzle does not become clogged and the imbalance in the gas ejection in the circumferential direction does not occur.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a gas burner device of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a front view seen from the direction of arrow B in FIG.

FIG. 4 is a vertical sectional side view showing an embodiment of the fuel nozzle of the gas burner device of the present invention.

5 is a cross-sectional view taken along the line CC of FIG.

6 is a cross-sectional view taken along the line DD of FIG.

7 is a cross-sectional view taken along the line EE of FIG.

[Explanation of symbols]

1 ... Gas fuel, 2 ... Gas chamber, 3 ... Main gas passage, 4 ... Main gas jet flow, 5 ... Combustion air, 6 ... Air flow, 7 ... Air supply port,
8 ... Combustion chamber, 9 ... Head plate, 10 ... Spark plug, 11 ...
Discharge spark, 12 ... Combustor wall, 13 ... Flame holding gas chamber, 14 ...
Gas manifold, 15 ... Fuel nozzle, 16 ... Flame stabilizer, 1
7 ... Nozzle head, 20 ... Flame holding gas throttle hole, 21 ... Flame holding gas inlet, 22 ... Flame holding gas passage A, 23 ... Flame holding gas resistance part, 24 ... Flame holding gas passage B, 25 ... Main gas injection port , 26
... Flame-holding gas injection port, 27 ... Nozzle outer wall, 28 ... Nozzle inner wall, 29 ... Flame-holding gas narrow passage, 30 ... Blind plate.

Claims (8)

[Claims] 1. A plurality of fuel nozzles having a main fuel injection port and a flame holding fuel injection port are provided, and fuel is distributed and supplied from a gas chamber of a manifold to the main fuel injection port and the flame holding fuel injection port. In the formed gas burner device, the manifold is provided with a flame holding gas chamber adjacent to the gas chamber, the flame holding gas chamber and the gas chamber are connected by a throttle hole, and the flame holding gas chamber is formed. A gas burner device for a combustor, characterized in that the flame holding gas nozzles of the plurality of fuel nozzles are connected to each other. 2. A plurality of fuel nozzles having a main fuel injection port and a flame holding fuel injection port are provided, and fuel is distributed and supplied from the gas chamber of the manifold to the main fuel injection port and the flame holding fuel injection port. A gas burner device for a combustor, characterized in that the amount of flame holding gas fuel of the fuel nozzle is supplied to a plurality of fuel nozzles through a single throttle hole. 3. A plurality of fuel nozzles having a main fuel injection port and a flame holding fuel injection port are provided, and the fuel is distributed and supplied from the gas chamber of the manifold to the main fuel injection port and the flame holding fuel injection port. In the formed gas burner device, the manifold is provided with a flame holding gas chamber adjacent to the gas chamber, the flame holding gas chamber and the gas chamber are connected by a throttle hole, and the flame holding gas chamber is formed. A flame burner device for a combustor, wherein flame holding fuel gas is supplied to the flame holding gas nozzles of the plurality of fuel nozzles. 4. A gas flow passage between the flame-holding fuel injection port of the fuel nozzle and the flame-holding gas chamber is provided with flow resistance means for resistance to the flow of the flame-holding gas. Burner equipment for the combustor of. 5. The gas burner device for a combustor according to claim 3, wherein the flame holding gas flow passage is formed on the outer periphery of the main fuel flow passage. 6. The flame holding gas flow passage is formed in a screw shape on the outer periphery of the main fuel flow passage.
Alternatively, the gas burner device of the combustor according to item 5. 7. The gas burner device for a combustor according to claim 3, 4, 5 or 6, wherein the throttle hole is located at the center of the flame holding gas chamber. 8. The gas burner device for a combustor according to claim 3, wherein a window and a blind cover that covers the window are provided on the manifold wall surface facing the throttle hole.