JP2579474B2 - Fire extinguishing method for burner for coal-water slurry - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a coal-water slurry (hereinafter referred to as Coal Water Mixture).
In particular, the present invention relates to a method for igniting and extinguishing a burner for a burner. In particular, a burner that inserts an atomizer gun into a predetermined position inside the furnace to ignite and pulls out the atomizer gun from the furnace to extinguish the fire and blocks the burner equipment. The present invention relates to a method of igniting and extinguishing a burner for a CWM suitable for preventing damage.

[Conventional technology]

When igniting a burner for CWM, insert an atomizer gun inside the furnace, and when using steam as a spray medium, CW
Moisture in M may evaporate and coal particles in CWM may aggregate and block in the burner gun.

In order to eliminate such adverse effects, there has been proposed a method in which the inside of the burner is cooled and purged with water before the CWM is supplied to the burner during ignition of the burner (Japanese Utility Model Application No. 58-689).
52 (Japanese Utility Model Application No. 59-175847), Japanese Patent Application No. 58-50754 (Japanese Patent Application
176511). [Problems to be Solved by the Invention] However, according to the above-described conventional method, when there is a flame of a burner other than the burner to be ignited, the tip of the atomizer gun inserted into the furnace is placed in the furnace. There is a problem that the tip of the atomizer is subjected to thermal shock due to being rapidly heated to high temperature by radiant heat and simultaneously quenched by water having a large heat capacity, resulting in a shortened life due to thermal fatigue of the material.

In particular, when atomizing CWM fuel at high speed and injecting it to produce atomized CWM fuel, the atomizer gun and other parts are made of highly wear-resistant ceramics. There is a problem that a sudden change in heat of the gun or the like may cause instantaneous cracking or destruction of the atomizer gun or the like.

As described above, conventionally, no consideration has been given to the influence of the burner member due to the heat-temperature change, so that the life of the burner is shortened, the spray function of the burner is impaired, the combustion becomes unstable, and the boiler plant or the like is deteriorated. There was a problem that caused a trip.

An object of the present invention is to solve the above-mentioned problems of the prior art, to prevent clogging by coal particles in a burner for CWM and to prevent damage to the burner equipment, to extend the life of the burner equipment, and to achieve stable operation of the combustion device. It is an object of the present invention to provide a fire extinguishing method for a CWM burner.

[Means for solving the problem]

The above object is to supply a spray medium of steam or air to the atomizer gun when the burner is ignited, and then supply CWM to the atomizer gun after the internal atmosphere of the atomizer gun is sufficiently cooled by supplying water. This is achieved by purging at least the CWM passage in the atomizer gun with a cleaning fluid such as steam when the burner is extinguished.

[Operation] At the stage where the atomizer gun is inserted into the furnace and the tip of the atomizer gun is affected by the radiant heat in the furnace, a cooling fluid is inserted into the atomizer gun, preventing abnormal rise in the temperature of the atomizer. Is done.

The atomizer gun is then gradually cooled by a gradual charge of steam or air spray medium, water and CWM,
Effects of the atomizer on the members such as destruction and thermal fatigue due to thermal shock are prevented.

Also, by monitoring the temperature of the high temperature atmosphere of the atomizer gun and appropriately selecting the injection time of the spray medium, water, and CWM, the ignition can be performed smoothly and excessive cooling of the furnace can be prevented.

(Example of the invention)

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram showing one embodiment of a burner device for carrying out the method of the present invention.

The burner device shown in FIG. 1 is provided with a drive 4A for driving a steam valve 6 provided in the middle of a pipe 5A of the steam 1, and a water valve 7 provided in a middle of the pipe of the water 2. A drive 4B for driving is installed, and a drive 4C for driving the CWM valve 8 arranged in the middle of the pipe of CWM3 is installed. Further, a pipe provided with a water valve 7 and a CWM valve 8
A water-CWM switching valve 9 is disposed at a junction with the piping in which is disposed, and a drive 4D for driving the water-CWM switching valve 9 is provided.

The pipe 5A of the steam 1 is communicated with the outer cylinder passage 18 in the atomizer gun 13 through the flexible tube 11A.
The piping 5B from the CWM switching valve 9 is a flexible tube 11B
Through the inner cylinder passage 18 in the atomizer gun 13. The atomizer gun 13 is installed so as to be movable in the axial direction of the gun between the distances A and B in the figure according to the operation of the air cylinder 15 by the operation of the air switching valve 14.

A temperature element 23 is installed near the atomizer 21, and a temperature change of the temperature element 23 is detected by a temperature detector 24. The temperature detector 24 is connected to the sequence board 12 by electric connection. The sequence board 12 is connected to the drives 4A, 4B, and 4C via electrical connections a, b, and d.
Reference numeral 12 is connected to the drive 4D by the electric connection c. Furthermore, the sequence board 12 is electrically connected to the drive unit of the air switching valve 14.
Contacted by 10.

In FIG. 1, reference numeral 16 denotes a wind box, 17 denotes an air register, 20 denotes a furnace, and 22 denotes a throat.

Next, an example of an ignition / extinguishing method in the above-described burner device will be described. In this operation, a flow sheet of the operation procedure is shown in FIG. 2, and a temperature change near the atomizer 21 is shown in FIG.

During the ignition operation of the burner, the air switching valve 14 operates based on a signal from the sequence board 12, the air cylinder 15 moves from A to B in the drawing, and the atomizer 13 is inserted into the furnace (A in FIG. 2). ).

Atomizer gun at the start of insertion of atomizer gun 13 into furnace
The temperature 21 is the point I in FIG.

Then, the temperature of the atomizer 21 starts to rise rapidly due to the action of radiant heat in the furnace. When the temperature of the atomizer 21 by the temperature detector 24 exceeds the set temperature, the sequence board 12
The drive 4A is activated based on the signal from the controller, the steam valve 6 is opened, and the steam 1 is introduced into the outer cylinder passage 18 in the atomizer gun 13 through the pipe 5A and the flexible tube 11A, and is ejected from the atomizer 21 into the furnace. (B in FIG. 2).

The temperature of the atomizer 21 at the start of the steam 1 ejection is point II in FIG. 3. As the steam 1 is ejected, the atomizer 21 is gradually cooled, and the temperature of the atomizer 21 is gradually decreased.

Next, the drive 4B operates based on the signals of the electric connection b and the electric connection c from the sequence board 12, the water valve 7 is opened, and the water-CWM switching valve 9 is switched to the water side,
Water 2 is introduced into the inner tube passage 19 in the atomizer gun 13 via the pipe 5B and the flexible tube 11B (C in FIG. 2). By this operation, the temperature of the atomizer 21 is further decreased from the position III in FIG.

Next, the sequence is performed when the temperature detection value of the atomizer 21 by the temperature detector 24 becomes lower than the temperature set in advance as the temperature at which the water of the CWM evaporates and the coal particles do not agglomerate even if the CWM is supplied to the atomizer 21. Electrical connection c from panel 12
And the CWM valve 8 is opened based on each signal of the electric connection d and the water-C
When the WM switching valve 9 is switched to the CWM side, the piping 5
CWM3 is injected into the inner cylinder passage 18 in the atomizer 13 via B and the flexible tube 11B (D in FIG. 3).

As the temperature for determining the start of the above-mentioned CWM supply, considering the clogging of the coal particles in the atomizer gun 13, the internal atmosphere of the atomizer gun 13 is 150 ° C or less, preferably 1 ° C.
00 ° C. or lower is preferred.

The temperature of the atomizer 21 at this time is a point IV in FIG. 3, and the combustion of the CWM is started from the point of the IV, and the temperature of the atomizer 21 is also in a steady state. The combustion air is supplied from the wind box 16 through the air register 17 to the inside of the furnace 20 from the throat 22, and is atomized from the atomizer 21 by the atomized CWM3.
Mixed with.

In this way, the high-temperature changing part due to the in-furnace radiant heat at the tip of the atomizer is injected with fuel while being gradually cooled by steam → water → CWM. Since it can be avoided, cracking and breakage can be prevented even in the case of an atomizer made of a ceramic material, and the durability and reliability of the burner device can be improved. In addition, at the stage of charging the CWM3 into the atomizer gun 13, the temperature of the atomizer gun 13 is lower than a predetermined temperature, so that evaporation and condensation of the CWM can be prevented.

In the embodiment described above, the atomizer by the temperature detector 24 is used.
The temperature of the vicinity 21 is detected, and the drive of each valve is operated from the sequence board 12 based on the detected temperature value. The output may be output to each drive, and each drive may be operated.

When the temperature of the atomizer 21 is continuously monitored by the temperature detector 24, the switching timing of each valve is determined, and the sequence board 12 outputs the drive to each of the drives 4A, 4B, 4C, and 4D to operate each valve. 2 can be controlled so that the temperature rise of I → II in FIG. 2 is minimized, and the optimal switching operation of each valve is selected from the relationship between the temperature drop gradient between II → III and III → IV and time. it can. For this reason, the purge amounts of the steam 1 and the water 2 charged into the furnace from the atomizer 21 can be effectively selected, and the CWM can be stably supplied without cooling the inside of the furnace more than necessary.

Next, at the time of fire extinguishing of the burner, as shown in FIG. 2, from the combustion operation of CWM (E in FIG. 2), the drive 4B operates based on the signal from the sequence board 12, and the water valve 7 is opened,
The water-CWM switching valve 9 is switched to the water side, the supply of CWM3 to the atomizer gun 13 is stopped (F in FIG. 2), the drive 4C operates to close the CWM valve 8, and the atomizer gun 13 is closed.
(G in FIG. 2).

Next, after the supply of water to the atomizer gun 13 is stopped, the drive 4A operates, the steam valve 6 is closed, and the supply of the steam 1 to the atomizer gun 13 is stopped (H in FIG. 2). Next, based on a signal from the sequence board 12, the air switching valve 14 operates, the rear end of the air cylinder 15 moves to the position shown in FIG. 1A, and the atomizer gun 13 is pulled out of the furnace (FIG. 2). I).

When the burner is extinguished, it is important to prevent clogging by the coal particles in the CWM.
It is necessary to purge the inside. For this reason, when the atomizer gun 13 is pulled out of the furnace, it is preferable that the atomizer 21 is gradually cooled. In order to avoid rapid cooling of the atomizer 21, water is supplied to the atomizer gun 13 at the same time as the steam 1 is supplied to the atomizer gun 13. Purge by 2 and atomization into the furnace are good.

Even when the burner is extinguished, the temperature detector 24 detects the temperature in the vicinity of the atomizer 21, outputs the temperature from the sequence board 12 to each drive based on the detected temperature value, and may operate each drive. It is also possible to output the operating procedure and timing of each drive to each drive according to a preset time chart, and to operate each drive.

In the present invention, when the burner is ignited, steam → water → CW
It is not limited to the procedure of charging M, and instead of steam, a spray medium capable of lowering the cooling rate for the atomizer 21 than water can be used. Air can also be used as such a spraying medium.

In addition, in any operation of steam → water → CWM or air → water → CWM, the steam or air atomizer gun
The time when the charging of the atomizer 13 is started may be any stage from the stage affected by the radiant heat in the furnace to the atomizer 21 to the stage where the atomizer gun 13 is set at a predetermined position. Therefore, it is most effective to start introducing steam or air while the atomizer gun 13 is moving inside the furnace.However, the movement of the atomizer gun 13 stops, and the atomizer gun 13 stops at a predetermined position. You may put in immediately after doing.

Next, in the system shown in FIG. 1, an example in which all of the valves are provided with a driving device as a valve configuration has been described. However, the valve structure and the driving method can be appropriately selected. Alternatively, the valve may be manually operated. Also,
It goes without saying that the cylinder for inserting the atomizer gun 13 into the furnace and for pulling out the atomizer gun 13 from the furnace is not limited to the electric type, but may be a manual type. Furthermore, the temperature element is not limited to the outer peripheral surface of the atomizer 21, but may be installed in the high temperature atmosphere inside the atomizer 21 or near the atomizer 21.

〔The invention's effect〕

As described above, according to the present invention, when the burner is ignited, the CWM is ignited while the atomizer is gradually cooled without being rapidly cooled, and when the burner is extinguished, the inside of the atomizer gun is purged. Therefore, the following effects can be exhibited.

It is possible to prevent a change in the structure of the material of a burner device such as an atomizer and a decrease in strength, and to prevent a decrease in the life of the burner device such as an atomizer. In particular, when the atomizer material is ceramics, cracking and breakage can be prevented. In addition, it is possible to avoid loosening of the screw tightening portion and the like due to thermal expansion and rapid contraction.

CWM in atomizer gun during ignition and fire extinguishing
Stable CW that can prevent clogging due to coal particles inside
M combustion operation can be performed.

Further, when the introduction of the fluid to the atomizer gun is performed by a time chart or a temperature monitoring control, the temperature fluctuation width of the atomizer can be suppressed to a minimum, and the above-mentioned effect is more highly achieved.

A minimum amount of a cooling medium such as steam, sky, or water is supplied to the atomizer gun so that excessive cooling in a furnace such as a boiler can be avoided.

[Brief description of the drawings]

1 is a system diagram of a burner apparatus for carrying out the method of the present invention, FIG. 2 is a flowchart showing one embodiment of the method of the present invention, and FIG. 3 is a temperature change with respect to time around an atomizer at the time of burner ignition. FIG. 1 ... Steam, 2 ... Water, 3 ... CWM, 6 ... Steam valve, 7 ... Water valve, 8 ... CWM valve, 9 ... Water-CWM switching valve, 12 ... Sequence board, 13 ... … Atomizer Gun, 14…
... air switching valve, 15 ... air cylinder, 16 ... wind box, 17 ...
… Air register, 18 …… Inner cylinder passage, 19 …… Outer cylinder passage, 20
…… In the furnace, 21 …… Atomizer, 22 …… Throat, 23 ……
Temperature element, 24 ... Temperature detector.

Claims (5)

(57) [Claims] 1. A coal-water slurry which burns a coal-water slurry using air or steam as a spray medium, inserts an atomizer gun of a burner for a coal-water slurry into the furnace and ignites it, and withdraws the atomizer gun from the furnace during fire extinguishing. In the method of igniting and extinguishing a slurry burner, when the burner is ignited, air or a spray medium of steam is supplied to the atomizer gun, and then water is supplied to the atomizer gun, and after the temperature near the tip of the atomizer gun decreases, the atomizer is supplied to the atomizer gun. A method for point-extinguishing a burner for a coal-water slurry, comprising a step of supplying a coal-water slurry and purging at least a coal-water slurry supply passage of an atomizer gun with a cleaning fluid when the burner is extinguished. 2. The method according to claim 1, wherein the supply of the spray medium to the atomizer gun is started at a stage where the atomizer gun is affected by radiant heat in the furnace.
A method for extinguishing a fire for a coal-water slurry burner according to claim 7. 3. The supply of the coal-water slurry to the atomizer gun is performed at an ambient temperature of 150 ° C. inside the atomizer gun.
The method according to claim 1, wherein the method is started when the following conditions are satisfied. 4. The method according to claim 1, wherein said cleaning fluid is steam. 5. The supply of the coal-water slurry to the atomizer gun is performed at an ambient temperature of 100 ° C. inside the atomizer gun.
4. The method for extinguishing a coal-water slurry burner according to claim 3, wherein the method is started when the following conditions are satisfied.