JPS63194126A - Method for ignition and extinguishment of coal-water slurry burner - Google Patents

Abstract

PURPOSE:To lengthen the service life of burner apparatus by preventing its clogging or damage and ensure the steady operation of a combusting device by cooling stepwise an atomizer at the time of burner ignition and purging the atomizer gun at the time of extinguishment. CONSTITUTION:At the time of burner ignition operation, an air switch valve 14 is actuated based on the signal from a sequence panel 12, and an atomizer gun 13 is inserted into the furnace. Steam 1 is introduced through piping 5A and flexible tube 11A into an outer shell passage 18 and ejected into the furnace through an atomizer 21. The atomizer 21 is gradually cooled down as steam 1 is ejected, and a water valve 7 is opened to introduce water 2 into an inner tube passage 19 in the atomizer gun 13 for further cooling. A water-coal-water slurry mixing (CWM) switch valve 9 is switched to the CWM side to feed CWM to the inner tube passage 18. On the other hand, when the burner is to be extinguished, a drive 4B is actuated based on the signal from the sequence 12 cause the water valve 7 to be opened and the water-CWM switch valve 9 to be switched to the water side to stop the supply of CWM 3 to the atomizer gun 13.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to coal-water slurry (Coal Water M
(hereinafter simply referred to as CWM) burner ignition/extinguishing method, in particular, the method of igniting and extinguishing CWM fuel in a burner, in which an atomizer gun is inserted into a predetermined position inside the furnace to ignite it, and the atomizer gun is pulled out from inside the furnace to extinguish it. The present invention relates to a method for igniting and extinguishing a CWM burner suitable for preventing damage to burner equipment.

[Conventional technology]

When igniting a CWM burner, insert an atomizer gun inside the furnace and use steam as the atomizing medium, C
The water in the WM evaporates and the coal particles in the CWM agglomerate,
There is a risk of blockage in the burner gun.

In order to eliminate such adverse effects, a method has been proposed in which the inside of the burner is cooled and purged with water at the time of ignition of the burner and before CWM is supplied to the burner (Japanese Patent Application Laid-Open No. 1983-1989).
68952, Japanese Unexamined Patent Publication No. 58-50754).

[Problem that the invention seeks to solve]

However, in the conventional method described above, when there is a flame from a burner other than the burner being ignited, the tip of the atomizer gun inserted into the furnace is rapidly heated to a high temperature by the radiant heat inside the furnace, and at the same time the heat capacity is reduced. Since the tip of the atomizer is rapidly cooled by a large amount of water, the tip of the atomizer is subjected to a thermal shock, resulting in problems such as a shortened lifespan due to thermal fatigue of the material.

In particular, when a 7D miser gun or the like is made of highly wear-resistant ceramics in order to mix and inject CWM at high speed and atomize the CWM fuel, ceramics themselves have high hardness but are brittle. There is a problem in that the atomizer gun, etc., may crack or break instantly due to rapid thermal changes in the atomizer gun, etc.

In this way, in the past, no consideration was given to the effects of heat and temperature changes on burner components, which shortened the life of the burner, impaired the spray function of the burner, destabilized combustion, and caused damage to boiler plants, etc. There was a problem that caused tripping, etc.

The purpose of the present invention is to solve the problems of the prior art described above,
An object of the present invention is to provide a method for turning on and extinguishing a CWM burner, which can extend the life of the burner equipment by preventing clogging due to coal particles in the CWM burner, damage to the burner equipment, etc., and ensure stable operation of a combustion device.

[Means for solving problems]

The above purpose is to supply an atomizing 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 has been 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 extinguishing the burner.

[Effect]

When 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, thereby preventing the atomizer from becoming abnormally heated.

The atomizer gun then uses a steam or air atomizing medium,
The stepwise introduction of water and CWM cools down the atomizer gradually, preventing damage to the atomizer due to thermal shock and thermal fatigue.

In addition, by monitoring the temperature of the part of the atomizer gun that becomes a high-temperature atmosphere and appropriately selecting the injection timing of the atomizing medium, water, and CWM, ignition can be made smooth and excessive cooling in the furnace can be prevented.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings. 1st
The figure 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 equipped with a drive 4A that drives a steam valve 6 disposed in the middle of a steam 1 piping 5A, and a water valve 7 disposed in the middle of a water 2 piping.
Drive 4B is installed to drive CWM3.
A drive 4C is installed to drive a CWM valve 8 disposed in the middle of the piping. Furthermore, at the junction of the pipe in which the water valve 7 is disposed and the pipe in which the CWM valve 8 is disposed, there is water-C.
A WM switching valve 9 is provided, and a drive 4D for driving this water-○WM switching valve 9 is installed.

The steam 1 piping 5A is connected to the outer cylinder passage 18 inside the atomizer gun 13 via the flexible tube 1)A, and the piping 5B from the water-CWM switching valve 9 is connected to the inside of the atomizer gun 13 through the flexible tube IIB. It communicates with the inner cylinder passage 18. This atomizer gun 13 is installed so as to be movable in the axial direction of the gun between distances A and B in the figure in accordance with the operation of an air cylinder 15 by the operation of an air switching valve 14.

A temperature element 23 is installed near the atomizer 21, and the temperature change of this temperature element 23 is detected by the temperature detector 2.
4 is detected.

The temperature sensor 24 is connected to the sequence board 12 through an electrical connection. In addition, the sequence board 12 has a drive 4A,
The drive 4B and the drive 4C are connected to each other by electrical connections a, b, and d, and the sequence board 12 is connected to the drive 4D by an electrical connection C. More sequences! 12 is connected to the drive section of the air switching valve 14 by an electrical connection 10.

In addition, in Figure 1, 16 is a wind box, 17 is an air register, 2
0 is the inside of the furnace, and 22 is the throat.

Next, an example of an ignition/extinguishing method in the burner device as described above will be explained. During this operation, a flow sheet of the operating procedure is shown in FIG. 2, and temperature changes near the atomizer 21 are shown in FIG.

When the burner is ignited, the air switching valve 14 is activated based on a signal from the sequence panel 12, the air cylinder 15 moves from A to B in the figure, and the atomizer gun 13 is inserted into the furnace (see Figure 2). A).

Atomizer 21 when the atomizer gun 13 starts to be inserted into the furnace
The temperature is the point marked ■ in Figure 3.

Then, the temperature of the atomizer 21 begins to rise rapidly due to the action of radiant heat within the furnace. When the temperature of the atomizer 21 determined by the temperature detector 24 reaches or exceeds the set temperature, the drive 4A is activated based on the signal from the sequence panel 12, the steam valve 6 is opened, and the steam 1 is sent to the atomizer via the piping 5A and the flexible tube IIA. It is introduced into the outer cylinder passage 18 in the gun 13, and is ejected from the atomizer 21 into the furnace (B in FIG. 2).

The temperature of the atomizer 21 at the time when the steam 1 starts spewing out is at point H in FIG.
temperature gradually decreases.

Next, the drive 4B is activated based on the signals from the electrical connections SNO and C from the sequence panel 12, the water valve 7 is opened, and the water-CWM switching valve 9 is switched to the water side, and the piping 5B and Water 2 is introduced into the inner cylinder passage 19 in the atomizer gun 13 through the flexible tube IIB (C in FIG. 2). Through this operation, the temperature of the atomizer 21 continues to fall from the position marked with ■ in FIG. 3.

Next, when the temperature detected by the temperature detector 24 of the atomizer 21 falls below a preset temperature at which the water in the CWM will evaporate and the coal particles will not aggregate even if the CWM is introduced into the atomizer 21. CWM based on each signal of electrical connection C and electrical connection d from sequence board 12
By opening the valve 8 and switching the water-WM switching valve 9 to the CWM side, the piping 5B and the flexible tube 1
) B to the inner cylinder passage 18 in the atomizer 13.
(D in Figure 3).

Considering the clogging of coal particles in the atomizer gun 13, the temperature for determining the start of CWM supply described above is as follows:
The internal atmosphere of the atomizer gun 13 is preferably 150°C or lower, preferably 100°C or lower.

The temperature of the atomizer 21 at this time is the point ■ in FIG. 3, and the combustion of CWM starts from this point ■.
The temperature of the atomizer 21 also becomes steady. The combustion air is supplied from the wind box 16 through the air register 17 to the throat 22 into the furnace 20, and is mixed with the atomized CWM 3 from the atomizer 21.

In this way, the part at the tip of the atomizer where the temperature changes due to the radiant heat inside the furnace is cooled step by step by steam → water → CWM while fuel is injected, reducing the large thermal shock that occurs when parts are rapidly heated and cooled. CWM can be avoided even in the case of an atomizer made of ceramic material, and the durability and reliability of the burner equipment can be improved.
3, the temperature of the atomizer gun 13 is below a predetermined temperature, so that evaporation and condensation of CWM can be prevented.

In the embodiment described above, the temperature near the atomizer 21 is detected by the temperature detector 24, and the response drive is operated from the sequence board 12 based on the detected temperature value. may be outputted from the sequence board 12 to each drive according to a preset time chart, and each drive may be operated.

In addition, the temperature of the atomizer 21 is continuously monitored by the temperature detector 24, the switching timing of the response is determined, and the timing is outputted from the sequence board 12 to each drive 4A, 4B, 4C, and 4D. ■−■ in Figure 2
It can be controlled to minimize the temperature rise of ■→■
, I-rl/, the optimum switching operation for answering can be selected from the relationship between the temperature decrease gradient and time. Therefore, the purge amounts of steam 1 and water 2 introduced into the furnace from the atomizer 21 can be effectively selected, and CWM can be stably supplied without cooling the inside of the furnace more than necessary.

Next, when the burner is extinguished, as shown in Fig. 2, the drive 4B is activated based on the signal from the sequence panel 12 from the CWM combustion operation (E in Fig. 2), the water valve 7 is opened, and the - The CWM switching valve 9 is switched to the water side, the supply of CWM 3 to the atomizer gun 13 is stopped (F in Figure 2), the drive 4C is activated and the CWM valve 8 is closed,
Supply water 2 to the atomizer gun 13 (G in Figure 2)
.

Next, after the supply of water to the 7 atomizer gun 13 is stopped, the drive 4A is activated, the steam valve 6 is closed, and the supply of steam 1 to the atomizer gun 13 is stopped (the second
Figure H) 0th order sequence! ! 1) Based on the signal from 2, the air switching valve 14 operates, the rear end of the air cylinder 15 moves to the position shown in Figure 1, and the atomizer gun 13 is pulled out from the furnace (as shown in Figure 2). 1).

When extinguishing the burner, it is important to prevent clogging by coal particles in the CWM, and therefore it is necessary to purge the inside of the inner cylinder passage 19, which is the passage of the CWM 3. For this reason, when pulling out the atomizer gun 13 from the furnace, it is preferable that the atomizer 21 is gradually cooled.
In order to avoid rapid cooling of steam 1, water 2 is supplied to the atomizer gun 13 at the same time as steam 1 is supplied to the atomizer gun 13.
Purging and atomization into the furnace are good.

Even when the burner is extinguished, the temperature near the atomizer 21 may be detected by the temperature detector 24, and based on the detected temperature value, the sequence board 12 may output it to each drive to operate each drive. It is also possible to output the operating procedure and timing of each drive to each drive in accordance with a predetermined time chart, and to operate each drive.

In the present invention, when igniting the burner, steam → water - CW
The method is not limited to the step of adding M, and instead of steam, it is possible to use a spraying medium that can lower the cooling rate of the atomizer 21 than water.Air can be used as such a spraying medium. You can also.

In addition, in the case of either steam-water-CWM or air-water-CWM operation, the time when steam or air starts to be introduced into the atomizer gun 13 is from the stage when the atomizer 21 is affected by radiant heat in the furnace to the time when the atomizer 21 is affected by radiant heat in the furnace. gun 1
Therefore, it is most effective to start introducing steam or air while the atomizer gun 13 is moving inside the furnace. However, atomizer gun 1
The atomizer gun 13 may be turned on immediately after the atomizer gun 13 stops moving at a predetermined position.

Next, an example in which all the valves in the system shown in FIG. , the valve may be operated manually;
It goes without saying that the cylinder for inserting the atomizer gun 13 into the furnace and for withdrawing the atomizer gun 13 from the furnace is not limited to an electric type, but can also be a manual type. Furthermore, the temperature element is not limited to the outer circumferential surface of the atomizer 21, but also inside the atomizer 21 or the atomizer 2.
It can also be installed in a high temperature atmosphere near 1.

〔Effect of the invention〕

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

■ It is possible to prevent changes in the structure and decrease in strength of the material of burner equipment such as atomizers, and it is possible to prevent a decrease in the life of burner equipment such as atomizers. Especially when the atomizer material is ceramic, cracking and damage can be prevented. Further, it is possible to avoid loosening of screw tightening parts and the like due to thermal expansion and sudden contraction.

■ CW inside the atomizer gun during ignition and extinguishing
Blockage due to coal particles in M can be prevented, and stable CWM combustion operation can be performed.

Furthermore, if the injection of fluid into the atomizer gun is carried out using a time chart or temperature monitoring control, (1) temperature fluctuations in the atomizer section can be minimized, and the above effect (2) can be achieved to a higher degree.

■ The minimum amount of cooling medium such as steam, air, water, etc. is injected into the atomizer gun, making it possible to avoid excessive cooling in boilers and other furnaces.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a burner device for carrying out the method of the present invention, Fig. 2 is a flowchart showing an embodiment of the method of the present invention, and Fig. 3 is a change in temperature around the atomizer over time when the burner is ignited. 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...
...Furnace, 21. Old... Atomizer, 22...
- Throat, 23 - Old... Temperature element, 24...
...Temperature detector. Representative Patent Attorney Masaru Nishimoto - Figure 1 1, -02. -83412

Claims (5)

[Claims] (1) The atomizer gun of the coal-water slurry burner is inserted into the inside of the furnace and ignited, and when extinguishing, the atomizer gun is pulled out from the furnace. In the ignition/extinguishing method, when the burner is ignited, an atomizing medium of air or steam is supplied to the atomizer gun, then water is supplied to the atomizer gun, and after the temperature near the tip of the atomizer gun has decreased, coal- A method for igniting and extinguishing a coal-water slurry burner, comprising the steps of supplying water slurry and purging at least the coal-water slurry supply path of an atomizer gun with a cleaning fluid when extinguishing the burner. (2) Supplying the above spray medium to the atomizer gun:
The method of igniting and extinguishing a burner for coal-water slurry according to claim 1, characterized in that the method starts when the atomizer gun is affected by radiant heat in the furnace. (3) The supply of the coal-water slurry to the atomizer gun starts when the atmospheric temperature inside the atomizer gun becomes 150°C or less. How to ignite and extinguish a burner for water slurry. (4) The method for igniting and extinguishing a burner for coal-water slurry according to claim (1), wherein the cleaning fluid is steam. (5) The supply of the coal-water slurry to the atomizer gun starts when the atmospheric temperature inside the atomizer gun becomes 100°C or less. How to ignite and extinguish a burner for water slurry.