JP2594304B2 - Method for igniting and extinguishing a slurry burner in a slurry combustion device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for igniting and extinguishing a slurry burner in a slurry combustion apparatus, and particularly to a slurry combustion apparatus suitable for preventing solidification and blockage of a slurry in a pipe. And a method for igniting and extinguishing a slurry burner.

[Conventional technology]

As a method of burning coal and water slurry (hereinafter referred to as CWM), there is a direct combustion method by spray atomization. Since this method can treat solid coal in a fluid state, it can control the flow rate and burner There is an advantage that can be simplified, such as a simple structure, which is not available in raw water heating. Since CWM is a mixture of water and coal particles, the coal particles coagulate and solidify when water is depleted, and the coal particles precipitate and coagulate and consolidate when the proportion of water increases.

FIG. 3 is a diagram showing a system of a conventional CWM combustion device. This device supplies a CWM burner 9 having an atomizer for spraying CWM at a tip thereof and CWM1 to the CWM burner 9.
CWM comprising a CWM supply pipe 2, a CWM water purge valve 4, a CWM stop valve 5, a CWM burner inlet pipe 6, and a CWM flexible hose 7.
The supply system and steam 11 as a spray medium to the CWM burner 9
A spraying medium supply system comprising a steam supply pipe 12, a steam stop valve 13 and a steam flexible hose 15,
Water supply pipe connected to the CWM water purge valve 4 of the CWM supply system
And a water supply system including a water stop valve 23. The CWM water purge valve 4 is a three-way valve. Reference numerals 8 and 16 denote pressure gauges provided in the CWM supply system and the spray medium supply system, respectively.

In such a configuration, when the CWM burner 9 is ignited, the steam stop valve 13 is first opened and the CWM burner 9 is
At the same time, the CWM water purge valve 4 is connected to the water supply system and C
The CWM burner inlet pipe 6 and the CWM flexible hose 7 are moistened with water 21 by opening the CMW stop valve 5 and the water stop valve 23 at a position where the WM supply system communicates. Next, the CWM water purge valve 4 is set to C
The position is switched to a position where the WM supply pipe 2 and the CWM burner inlet pipe 6 communicate with each other, and the CWM 1 is charged into the CWM burner 9 to ignite.

On the other hand, when extinguishing the CWM burner 9, the CWM supply is stopped by switching the CWM water purge valve 4 to a position communicating the CWM supply system and the water supply system, and the CWM supply after the CWM water purge valve 4 is stopped. CWM1 in the system is purged with water 21 so that CWM1 does not remain in CWM burner 9. Then water prevention valve 2
3. Close the steam stop valve 13 to stop the operation of each system. Japanese Patent Application Laid-Open No. Sho 58-58
68952 and 58-50754.

[Problems to be solved by the invention]

However, the conventional technique has a problem that the purge of the CWM supply system is incomplete. That is, when the CWM supply system is purged with water 21 at the time of fire extinguishing, CWM1 in the CWM supply system after the CWM water purge valve 4 is gradually replaced with water, but coal particles remain unless the plug flow is complete. After stopping the purge with water 21, the coal particles settle and adhere to the inner wall of the pipe. For this reason, when the ignition and extinguishing of the CWM burner 9 are repeated, the coal particles gradually accumulate in the CWM burner inlet pipe 6 in a layered manner. There was a risk of clogging. By the way, it is preferable to lengthen the purging time with water 21 in order to complete the purging of CWM1 as much as possible.However, if a large amount of purge water is charged into the furnace of the combustion device in a high-temperature atmosphere, the gas temperature in the furnace decreases. However, there is a problem that stable combustion in another CWM burner is prevented and unnecessary heat loss occurs. There is also a problem that the furnace material is rapidly cooled and destroyed by the purge water. On the other hand, at the time of ignition, the CWM burner 9 is directly purged with water.
There is a problem that the tip of the burner 9 is rapidly cooled and the ceramic material is destroyed.

An object of the present invention is to solve the above-mentioned problems of the prior art, and
The CWM supply system during ignition and digestion of the M burner
It is an object of the present invention to provide a method for igniting and extinguishing a slurry burner in a slurry combustion apparatus which can be almost completely purged without quenching and without using a large amount of purge water.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a slurry combustion apparatus that supplies a slurry after purging a slurry supply system with water when igniting a slurry burner, and stops supplying the slurry during fire extinguishing, and then purges the slurry supply system with water. In the method for igniting and extinguishing a slurry burner according to the above, at the time of ignition, the slurry supply system is purged with air or / and steam,
After purging with water, supply the slurry.
After the supply of the slurry is stopped, the slurry supply system is purged with water and further purged with air or / and steam.

[Action]

When the slurry burner is ignited, the slurry supply system is purged with air or / and steam, and then the slurry is supplied after being purged with water, so that the slurry burner is purged with water after being cooled to some extent by air / and steam. That is, rapid cooling of the slurry burner can be avoided, so that damage due to thermal fatigue of the burner device can be prevented, and evaporation of water in the supplied CWM can be prevented, so that coal particles are solidified. Nor. Further, when extinguishing the slurry burner, after the supply of the slurry is stopped, a water purge is performed, and the air or /
By purging with steam and steam, the amount of purge water used can be minimized, and the residual purge water containing coal particles can be completely purged with air or / and steam. It is possible to reduce the adverse effects of the water purge on the members and to prevent the adverse effects such as clogging and clogging of the pipe due to residual coal.

In the present invention, the input flow rate and time of water, steam or air are preferably managed by using a thermometer installed in the CWM burner and a flow meter installed for each purge fluid, but installed in each purge fluid supply system. It can also be performed using a pressure gauge as a guide.

〔Example〕

 Next, the present invention will be described in more detail with reference to examples.

FIG. 1 is an apparatus system diagram showing one embodiment of the present invention. This device has a CWM burner 9 equipped with an atomizer using ceramics as a wear-resistant material for spraying CWM1,
A CWM supply system for supplying CWM1 to the CWM burner 9;
A spray medium supply system for supplying a spray medium to the M burner 9;
It mainly comprises a purge system branched from the spray medium supply system and communicating with the CWM supply system, and a water supply system connected to the purge system. CWM supply system is C
WM supply pipe 2, CWM return valve 3, CWM water purge valve 4, CWM stop valve 5, CWM burner inlet pipe 6, and CWM flexible hose 7
The spray medium supply system includes a steam supply pipe 12, a steam stop valve 13, a steam burner inlet valve 14, and a steam flexible hose 15. The purge system is branched from a pipe downstream of the steam stop valve 13 of the spray medium supply system.
The water supply system includes a purge pipe having a steam purge inlet valve 17 and a steam purge valve 24, and the water supply system includes a water supply pipe 22 having a water stop valve 23 communicating with the steam purge valve 24 of the purge system. In addition, 10 is a CWM return pipe for communicating the CWM return valve 3 of the CWM supply system with a CWM storage tank (not shown), and 8 and 16 are connected to the CWM burner 9 of the CWM supply system and the spray medium supply system, respectively. It is a pressure gauge provided.

In such a configuration, when the CWM burner 9 is to be ignited, first, the CWM return valve 3 is set to a position where the CWM supply pipe 2 communicates with the CWM return pipe 10, and then a CWM supply pump (not shown) is started to activate the CWM1 Is circulated between the CWM supply pipe 2, the CWM return valve 3, the CWM return pipe 10, and a CWM storage tank (not shown),
Enter WM1 input preparation stage. Next, after setting the CWM burner 9 to a state in which fuel may be charged, the steam stop valve 13 and the steam burner inlet valve 14 are opened, and the
Steam is supplied to the CWM burner 9 to cool the tip of the CWM burner 9 which has become hot due to the radiant heat of another CWM burner in the furnace. Next, the CWM water purge valve 4 is switched to a position communicating the purge system and the CWM supply system, and the steam purge valve 24 is switched to a position communicating the CWM supply system and the spray medium supply system, and the steam purge inlet valve 17 is opened. Steam is also supplied to the CWM supply system, and the CWM flow path at the tip of the CWM burner 9 is first purged with steam and cooled. Thereafter, the steam purge valve 24 is switched to a position where the CWM supply system and the water supply system communicate with each other.
The water stop valve 23 is opened to replace the steam in the CWM supply system and the inside of the CWM burner 9 with water, and simultaneously cool the tip of the atomizer with water. Finally, by switching the CWM return valve 3 and the CWM water purge valve 4 to a position where all the CWM supply systems communicate, the water in the CWM burner inlet pipe 6, the CWM flexible hose 7, and the CWM burner 9 is replaced with CWM from water. , The spray combustion of CWM1 is started.

On the other hand, when extinguishing the CWM burner 9, first, the supply of the CWM1 to the burner 9 is stopped by switching the CWM return valve 3 so that the CWM supply pipe 2 and the CWM return pipe 10 form a circulation flow path. . Next, the water stop valve 23 is opened, and the steam purge valve is opened.
24 is connected to the water supply system and the CWM supply system.
By switching the WM water purge valve 4 to a position that connects the CWM supply system and the purge system, C remaining in the CWM supply system is reduced.
Purge WM1 with water 21. Next, the steam purge inlet valve 17
The steam purge valve 24 is switched to connect the CWM supply system and the spray medium supply system so that the water in the CWM supply system after the steam purge valve 24 and the CWM water purge valve 4 is replaced with steam. Purging coal particles remaining in the purge water in the CWM supply system without leaving the system. Next, as a complete stop operation of the CWM combustion device, the steam burner inlet valve 14 and the steam purge inlet valve 17 are closed to stop the supply of steam.

According to the present embodiment, when the CWM burner 9 is ignited, the temperature in the tip of the CWM burner 9 is gradually cooled by gradually switching the inside of the CWM supply system from steam to water and from water to CWM. In addition to preventing the ceramic member from being damaged by thermal shock, the CWM1
The agglomeration and solidification of coal particles due to rapid evaporation of water in the coal is avoided. In addition, since steam purge is performed before water purge, the amount of purge water can be reduced compared to cooling with water only, preventing stable combustion of another CWM burner in the furnace, and rapidly cooling members around the burner. Adverse effects can be minimized.

On the other hand, when extinguishing the CWM burner, after the CWM supply system is purged with water, the system can be switched to steam purge immediately, and the flow velocity of the purge fluid in the pipe can be made larger than in the conventional technology. Can be. Further, by increasing the amount of purge steam by minimizing the amount of purge water, it is possible to avoid misfire and rapid cooling of another CWM burner in the furnace.

In this embodiment, when the CWM burner 9 whose combustion is stopped receives the radiant heat of the flame of another operating CWM burner, the purge gas supplied to the CWM supply system from the steam purge inlet valve 17 of the purge system is used. Preferably, the steam is continuously supplied as it is, and the CWM burner 9 is continuously cooled.
This not only cools the CWM burner 9, but also purges the remaining coal particles in the system more completely, and
It is also a preparation operation when re-igniting the CWM burner. Further, in this embodiment, when the supply of CWM1 is stopped, the CWM water purge valve 4 is switched to a position communicating the CWM supply system and the purge system, and the CWM return valve 3 connects the CWM supply pipe 2 and the CWM return pipe 10. It is preferable to form a circulating flow at the communicating position. Thereby, even if the CWM water purge valve 4 is heated by the steam, the CWM in the CWM return valve 3 does not solidify due to the heating.

FIG. 2 is an apparatus system diagram showing another embodiment of the present invention. This device is obtained by adding an air supply system and an air purge system that branches off the air supply system to the device shown in FIG. The air supply system is for the burner seal,
It comprises a supply pipe 32 for air 31, an air seal valve 33, an air seal gun inlet pipe 34, and an air seal flexible hose 35, and is connected to an air seal box 36 communicating with an air seal passage 38 of the CWM burner 9. The air purge system branches off from the air supply pipe 32 and is a CWM stop valve 5a of the CWM supply system.
A purge pipe having an air purge valve 40 and a purge pipe branched from the air supply pipe 32 and having an air cooling valve 39 communicating with a pipe downstream of the steam stop valve 13 of the spray medium supply system. Has become.

In such a configuration, the air 31 passes through an air supply pipe 32, an air seal valve 33, an air seal gun inlet pipe 34, and an air seal flexible hose 35 for a burner seal.
It is introduced into the air seal box 36 of the CWM burner 9 to prevent the gas in the furnace from flowing backward from inside the furnace to outside when the pressure inside the furnace is positive. When the burner is digested, an air purge valve is used instead of steam purging after water purging the CWM burner 9.
The CWM stop valve 5a is opened so that the CWM stop valve 5a communicates with the CWM supply system and the air purge system, and the residual water in the CWM supply system after the CWM stop valve 5a is purged with the air 31. At this time, the spray medium supply system can also be purged by the air 31 by closing the steam stop valve 13 and opening the air cooling valve 39.

According to the present embodiment, as the purge fluid at the time of the ignition and digestion of the CWM burner 9, by performing stepwise with steam or / and air to water and water to steam or / and air,
The CWM 1 can be completely purged, and the shock due to the heat of the CWM burner 9 can be mitigated to prevent damage to components, thereby improving the life and reliability of the plant. Also, since the amount of water required for purging can be minimized and the latent heat loss of water can be reduced, a decrease in the furnace ambient temperature can be prevented, and interference with combustion of another CWM burner can be avoided.

In this embodiment, if air is purged at the time of ignition of the burner, the cooling effect at the tip of the gun of the CWM burner 9 is greater than that of steam, and the purging operation can be performed even when the steam source is not sufficient. Also by air
Purging the CWM supply system eliminates concerns about overheating of the CWM due to steam, evaporation of moisture, and solidification of coal particles.
Further, when air is used without using steam as the spraying medium, there is no fear of agglomeration and solidification of coal particles due to evaporation of water in the CWM. Can be ignited.
That is, it is also possible to perform ignition ignition of the CWM burner by using air as the spray medium and directly purging the slurry supply system with only air. In this embodiment, the air supply system may be different from that for the seal box 36.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, at the time of ignition and ignition of a slurry burner in a slurry combustion device, the inside of a slurry supply system can be efficiently purged without giving a thermal shock to a burner and a furnace.

[Brief description of the drawings]

FIG. 1 is an apparatus system diagram showing one embodiment of the present invention, FIG. 2 is an apparatus system diagram showing another embodiment of the present invention, and FIG.
It is a figure showing the system of the conventional slurry combustion device. 10… CWM return pipe, 14… Steam burner inlet valve, 17 …… Steam purge inlet valve, 24 …… Steam purge valve, 32 …… Air supply pipe, 33 …… Air seal valve, 36 …… Air seal box ,
39: air cooling valve, 40: air purge valve.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-194126 (JP, A) JP-A-59-176511 (JP, A) JP-A-59-71921 (JP, A)

Claims (2)

(57) [Claims] 1. A method for igniting and extinguishing a slurry burner in a slurry combustion apparatus for purging a slurry supply system with water when igniting a slurry burner and supplying the slurry after stopping the supply of the slurry when extinguishing the fire, and then purging the slurry supply system with water. At the time of ignition, the slurry supply system is supplied with air or /
And supplying the slurry after purging with water and further purging with water. At the time of fire extinguishing, after the supply of the slurry is stopped, the slurry supply system is purged with water and further purged with air or / and steam. For igniting and extinguishing a slurry burner in a slurry combustion apparatus. 2. A spraying medium vapor as a purge vapor,
The method for igniting and extinguishing a slurry burner in a slurry combustion apparatus according to claim 1, wherein air for a burner seal is branched and used as air for purging.