JP3520567B2 - Boiler flood prevention method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention is in the combustion stop of the boiler, to a full level prevention method for preventing the boiler is filled with water.

[0002]

2. Description of the Related Art When a boiler is stopped after the operation is stopped, the inside of the can is cooled by heat radiation and steam is changed into water . To do. Sometimes, it sometimes can internal pressure force is below atmospheric pressure, In such a state, the water is sucked into the canister through the water supply line, the can is filled with water.

[0003] When resuming the operation of the boiler remains filled with water, such as this, water-full level is heated to change to vapor canister internal pressure exceeds the allowable limit pressure increases rapidly.
Then, the boiler detects abnormal high pressure and stops operation.
It stopped or the safety valve actuated, and it gushed out from this safety valve.
Controlled by the boiler water equipment, a situation that auxiliary equipment such as fouling or damage to <br/> occurs. Moreover, the may not reach the point the safety valve is actuated, a droplet is large quantities dry season of poor vapor flows out of the mixed is not preferable.

[0004]

[Problems that the Invention is to Solve] solved by the present invention
The problem to be during the combustion stop of the boiler, and reliably prevent the inside of the vessel of the boiler is filled with water, when restarting the boiler,
Immediate supply of high-quality steam with good dryness
Der Ru.

[0005]

The present invention has been made to solve the above-mentioned problems, and the invention as set forth in claim 1
During combustion stop of the boiler, the can is full level of the boiler
Or it determines whether it is, can and was judged to be filled with water
In full water prevention method of a boiler for performing blanking row operation, when the can internal pressure force of the <br/> boiler is equal to or greater than a preset value,
It is characterized by starting a blow operation.

[0006] The present invention as described in claim 2, during the combustion stop of the boiler, when the can internal pressure force of the boiler falls below preset value, electrostatic provided to the water supply line of the boiler <br / > It is characterized by closing the valve.

[0007]

During combustion stop of the action] boiler, the can of the boiler is determined whether or not filled with water, can and <br/> it is determined that it is filled with water, have rows Bed row operation of the boiler when the can internal pressure force becomes equal to or larger than a preset value, and starts blowing operation.
By doing so, since the can and the can is a negative pressure state without opening the blow <br/> over valve, never draw air and sewage through blow pipe. Further, during combustion stop of the boiler,
When the can internal pressure force of the boiler falls below a preset value, by closing the motor-operated valve in the water supply line, to prevent suck water into Kan'nai through water supply line.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will now be described with reference to the drawings.
Will be described in detail. First, the first embodiment shown in FIG.
And explain. In FIG. 1, a boiler 1 includes a can body having a structure in which a substantially annular upper header 2 and a lower header 3 are connected by a plurality of water pipes 4. A burner 6 to which a blower 5 is connected is placed on the upper surface of the upper header 2.
A fuel supply line 8 provided with a fuel supply solenoid valve 7 is connected to the burner 6. Operation of the burner 6, the stop has to perform on the basis of the can internal pressure force of the boiler 1, based on the output signal from the pressure detector 9 connected to the upper header 2, a can internal pressure of the boiler 1 Once the force reaches a predetermined value, the burner 6 is stopped, the boiler
After 1 of the can internal pressure force is reduced to a predetermined value, the burner 6
Control to operate.

[0009] The lower header 3, the water supply line 12 is connected in which a check valve 10 and the water supply pump 11. Then, the water level control cylinder 13, the water level detector 14 is provided, the upper end of the water level control cylinder 13 is connected to the upper header 2 via the upper communication pipe 15, whereas the lower end is lower contact It is consolidated in the lower header 3 through the pipe 16. The water supply pump 11 includes the water level detector 14
Based on the output signal from the on-off control, the water level of the voice <br/> La 1 is adapted to be maintained at a predetermined level.

A main steam valve 17 is provided on the upper header 2.
A girder steam pipe 18 is connected. The steam generated in the boiler 1 is subjected <br/> is fed through the steam pipe 18 to each device.

[0011] The lower header 3, set the blow valve 19
The digit blow pipe 20 is connected. The tip of the blow pipe 20 is disposed in the drain groove (not shown) within.

[0012] In the configuration of this first embodiment, during the combustion stop of the ball <br/> Ira 1, to determine whether the can of the boiler 1 is <br/> at full level state, filled with water when it is determined that it is,
Perform a blow operation (full water blow operation) . At that time, when the can internal pressure force of the ball <br/> Ira 1 is equal to or higher than a preset value,
The blow operation Ru open Hajimesu open the blow valve 19. The <br/> judged whether or not the can of the boiler 1 is filled with water is carried out based on the output signal from the <br/> water level detector 14. The installation position of the water <br/> position detector 14, in addition to the Ru level control cylinder 13 in and to <br/>, may be Rukoto and in the upper header 2. The can
When pressure is negative flatly state, by opening the blow valve 19, the so through blow pipe 20 will suck sewage in the air and the water discharge groove, based on the output signal from the pressure detector 9 when the can internal pressure forces became more (0.2 kg / cm ² if example <br/> it was) value that is set in advance, the blow valve 1
9 open start the blow operation. By doing so, it is possible to prevent the occurrence of rust in the reactor that attributable suction mini air and sewage is mixed into the steam quality of the steam can be prevented.

[0013] The blow over operations, at the time of resuming the operation the boiler 1, the operation switch or combustion switch (both not Ministry
Can also be omitted) is in an odd line Migihitsuji turned on
And may other on the operation switch or the combustion switch is turned on in and during the combustion stop state, to be performed in the state of Sunawa Chi combustion waiting. In that case, the boiler 1 it is determined whether the cold-state,
When it is determined that the cold-state, the water level in the reactor is drained until the proper level by opening the blow valve 19. Determining the volume <br/> Ira 1 is whether cold-state is carried out by comparing the the temperature set value of the elapsed time after stopping the combustion or the water pipe 4,.

[0014] Next, a description is given of a second embodiment shown in FIG. Since the configuration of the second embodiment is basically the same as that of the first embodiment, the description of the configuration common to both is omitted. In this second embodiment, the electric valve 21 provided in the <br/> water supply line 12. The electric valve 21, the opening and closing control based on the output signal from the pressure detector 9, the combustion stop of the boiler 1 (if e DOO was 0.2 kg / cm ²⁾ can internal pressure force preset value below Then, the electric valve 21 is closed. Then, the pressure within the can is equal to or greater than (0.2 kg / cm ² if example preparative was) value that is set in advance
During operation of the water supply pump 11 was KOR, the electric valve 21
The Open.

According to the configuration of the second embodiment, even if the voice <br/> La 1 of the can is a negative pressure, no water can be sucked into the canister through the water supply line 12, the Boiler 1
When restarting the, it is possible to immediately supply the good quality of the steam of dryness fraction. When water is drawn into the can, but the water until in the <br/> steam pipe 18 there is input Rukoto, it can be reliably avoided such a situation. Also, can with the voice <br/> La 1 of the can is a negative pressure, the water flowing into the cans,
Water is not medicated at all, and the inside of the can easily corrodes.
That possibility but there was Tsu, according to the configuration, it is possible to reliably avoid such a situation.

[0016]

Effects of the Invention According to the present invention, during the combustion stop of the boiler, and reliably prevent the inside of the vessel of the boiler is filled with water, when restarting the boiler, the good quality of the steam of dryness fraction immediately subjected teapot can Rukoto.

[0017] Sunawa Chi, if elm invention described in claim 1,
The can the can is to be the negative pressure state, the blow valve is not opened, is not inhaling air and sewage through blow pipe. It was although I, it is possible to prevent the occurrence of rust in the reactor that attributable suction mini air and sewage is mixed into the steam quality of the steam can be prevented.

In addition,According to the invention of claim 2,Bo
Even if the pressure inside the can of the irra becomes negative,
In the canWhatWhen the boiler is restarted without being sucked,Dry
Immediate supply of good quality steamCan
It

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of a boiler to which the present invention is applied .

FIG. 2 is an explanatory diagram showing a second embodiment of a boiler to which the present invention is applied .

[Explanation of symbols]

1 boiler 12 Water supply line 21 Motorized valve

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Claims (2)

(57) [Claims] During combustion stop according to claim 1] boiler 1, in <br/> the can the boiler 1 it is determined whether or not filled with water, was determined as the full level and comes boiler performing blanking row operation in full water prevention method <br/>, when the can internal pressure force of the boiler 1 is equal to or greater than a preset value, full level method for preventing boiler, characterized in that to start the blow operation. Wherein during the combustion stop of the boiler 1, when <br/> can internal pressure force of the boiler 1 becomes equal to or less than a preset value, the voice
A method for preventing the boiler from being filled with water, characterized in that a motor-operated valve 21 provided in the water supply line 12 of La 1 is closed.