JP2005147581A - Soot blower device and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soot blower device capable of controlling a steam jetting amount in operation. <P>SOLUTION: This soot blower device has: a lance tube 7 extractable/insertable to the inside of a furnace 12, having a nozzle 18 in a tip part; a motor 5 rotationally driving the lance tube 7; and a poppet valve 3 adjusting a feeding-in amount of a cleaning medium to the lance tube 7. In the soot blower device, the lance tube 7 is inserted into the furnace 12, the cleaning medium is fed in the lance tube 7 through the poppet valve 3, and the cleaning medium is jetted to a cleaning target object 19 from the nozzle 18. The soot blower device is provided with a sensor 22 detecting whether the nozzle 18 faces the cleaning target object 19 or not. Based on a signal from the sensor 22, when the nozzle 18 faces the cleaning target object 19, the poppet valve 3 is opened to jet the cleaning medium from the nozzle 18. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a soot blower device called a soot blower that removes ash and the like adhering to and depositing on a heat transfer part such as a coal fired boiler by spraying a cleaning medium such as steam. The present invention relates to a soot blower apparatus suitable for adjusting the injection amount of a cleaning medium during a soot blower operation and suppressing steam erosion of an object to be cleaned (tube, coil, etc.) and a control method thereof.

  FIG. 5 is a diagram showing the overall configuration of the soot blower device. In the same figure, the code | symbol 11 shows the furnace exterior (outside wall) of a boiler, and the code | symbol 12 shows the inside of a furnace (inside a wall). The soot blower is supported by a wall box 1 attached to the furnace wall and a rear support 10 of the frame 8, and a lance tube 7 that is inserted into and extracted from the furnace 12 is arranged at right angles to the furnace wall.

  The lance tube 7 and the feed tube 6 have a double tube structure. When the motor 5 is rotated, the carriage 4 moves forward along the feed tube 6 while rotating the lance tube 7, and enters the furnace 12 into the lance tube 7. To insert. Steam, which is a high-pressure injection medium that cleans the inside of the furnace 12, is sent to the lance tube 7 through the feed tube 6 by the opening and closing operation of the poppet valve 3 at the rear of the soot blower, and a nozzle (not shown) provided in the lance tube 7. ) Is injected into the furnace. Reference numeral 2 is a roller bracket, and 9 is an operation box.

  FIG. 6 shows a state when the lance tube 7 is inserted into the furnace 12. Only in this state, the feed tube 6 that is the inner tube of the double tube emerges from the lance tube 7. When the motor 5 is reversely rotated from this state, the carriage 4 rotates the lance tube 7 in the reverse direction at the time of insertion, starts retreating along the feed tube 6, and pulls the lance tube 7 out of the furnace 12. That is, the soot blower device repeats the state of FIG. 5 and the state of FIG. The operation time varies depending on the insertion length of the lance tube 7, but it is an operation time of about 5 minutes one way.

  FIG. 7 shows an opening / closing mechanism of the poppet valve 3. FIG. 4A is a front view of the poppet valve opening / closing mechanism, and FIG. 4B is a side view of the poppet valve opening / closing mechanism. The poppet valve 3 is opened and closed by a link mechanism installed on the frame 8, the cam 14 is tilted by the movement of the carriage 4, and the trigger 15 at the top of the poppet valve 3 is tilted by pulling the arm, so that the poppet valve stem (see FIG. (Not shown) is pushed down and steam is ejected from the nozzle. FIG. 7 shows a state where the trigger 15 is tilted.

  In the conventional soot blower device, this link mechanism tilts the cam 14 (steam injection) almost simultaneously with the advancement of the carriage 4 (that is, insertion of the lance tube 7 into the furnace), and raises the cam 14 immediately before stopping the carriage after pulling back ( (Steam injection stop) mechanism. That is, the high pressure steam continues to flow at a constant amount while the steam is turned on and off by the poppet valve 3.

  According to this mechanism, the soot blower arranged at the position for cleaning the hanging pendant coil 24 portion as shown in FIG. 8 performs the steam injection while rotating 360 °, so there is no target coil (hanging coil 24). It is always blowing in the vertical direction. This upward and downward steam is not involved in cleaning and is wasted steam. The amount is about 50% of one soot blower consumption. Reference numeral 18 denotes a nozzle provided on the lance tube 7, 23 denotes a steam injection unnecessary range, and 25 denotes a steam injection required range.

  The same applies to the case of the horizontally placed coil 26 shown in FIG. 9, and since there is no object (the horizontally placed coil 26) in the lateral direction, the steam injection in the lateral direction is useless steam injection. The steam consumption is calculated as follows.

  The steam consumption in one soot blower operation differs depending on the place where it is placed, but if the average consumption per unit is 6 t / h, 1 ton of steam is ejected per operation per unit (When the operation time per time is 5 minutes × 2 = 10 minutes as described above). Considering the boiler as a whole, the installed number of long soot blowers in a 1000MW class coal fired boiler is about 50 units, so it takes 50 tons of steam to operate the soot blower sequentially and clean the entire boiler. Will be.

  Moreover, the present situation is that the soot blower is operated three times a day in the coal fired boiler. That is, the amount of steam consumed by the soot blower in one day operation is 150 ton / day. Therefore, the half of 75 ton is jetted to a place where there is no object, which is a wasteful consumption not related to the cleaning function which is the original device purpose. This is about 27,000 tons per year. The fuel cost can be reduced by reducing this useless steam.

  Another problem is that the lance tube advances steam against the target tube to remove the ash, but the reverse operation also injects steam, so the forward steam injection removes the ash and cleans it. The act of spraying steam again on the surface of the tube / coil that has become This steam injection at the time of backward movement becomes a problem as steam erosion of the tube.

  That is, in the conventional soot blower device, regardless of the presence or absence of the object and the degree of contamination of the object, the steam injection amount is constant until the operation is completed when the operation starts, and no consideration is given to the control of the amount. .

Patent documents related to soot blower devices include the following.

JP 2002-286221 A JP2002-213729

  In the above prior art, no consideration has been given to the amount of steam consumed as a cleaning medium, and the steam injection amount is constant until the operation is completed, regardless of the presence or absence of the object to be cleaned and the degree of contamination of the object. No consideration was given to the amount of control. As a result, it is uneconomical and has problems such as promotion of steam erosion on the object to be cleaned.

  An object of the present invention is to provide a soot blower apparatus that eliminates the disadvantages of the prior art, is economical, and that can suppress steam erosion on a cleaning object, and a control method therefor.

In order to achieve the above object, the first means of the present invention includes a lance tube that can be inserted and removed from the furnace and has a nozzle at the tip, a motor that rotationally drives the lance tube, steam for the lance tube, etc. A poppet valve that adjusts the amount of cleaning medium fed in, and the lance tube is inserted into a furnace, the cleaning medium is fed into the lance tube through the poppet valve, and the nozzle is applied to a cleaning object such as a tube or a coil. In a soot blower device for cleaning by jetting a cleaning medium,
A sensor is provided for detecting when the nozzle of the lance tube rotated by the motor is opposed to the object to be cleaned, and the nozzle of the lance tube is to be cleaned based on a signal from the sensor. When facing the object, the poppet valve is opened and a cleaning medium is ejected from the nozzle.

  The second means of the present invention is characterized in that, in the first means, the poppet valve can be switched to a plurality of stages of full opening, full closing and intermediate opening.

The third means of the present invention adjusts the amount of cleaning medium fed into the lance tube, a lance tube that can be inserted into and removed from the furnace and having a nozzle at the tip, a motor that rotationally drives the lance tube, and the lance tube. In a control method of a soot blower apparatus, comprising a poppet valve, inserting the lance tube into a furnace, sending a cleaning medium to the lance tube through the poppet valve, and jetting a cleaning medium from the nozzle to a cleaning object.
The opening of the poppet valve can be switched between full opening and intermediate opening, and it detects when the nozzle of the lance tube rotating by the motor is facing the object to be cleaned or not. When the nozzle of the lance tube faces the object to be cleaned based on the signal from the sensor, the poppet valve is fully opened and the cleaning medium is sprayed from the nozzle, and the nozzle of the lance tube is cleaned. When not facing the object, the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle.

The fourth means of the present invention is a lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip, a motor that rotationally drives the lance tube, and an amount of cleaning medium fed into the lance tube. In a control method of a soot blower apparatus, comprising a poppet valve, inserting the lance tube into a furnace, sending a cleaning medium to the lance tube through the poppet valve, and jetting a cleaning medium from the nozzle to a cleaning object.
The opening of the poppet valve can be switched between full opening and intermediate opening, and it detects when the nozzle of the lance tube rotating by the motor is facing the object to be cleaned or not. When the nozzle of the lance tube faces the object to be cleaned based on the signal from the sensor, the poppet valve is fully opened to inject the cleaning medium from the nozzle, and the lance tube is removed from the furnace. When extracting, the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle.

The fifth means of the present invention is a lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip, a motor that rotationally drives the lance tube, and an amount of cleaning medium fed into the lance tube. In a control method of a soot blower apparatus, comprising a poppet valve, inserting the lance tube into a furnace, sending a cleaning medium to the lance tube through the poppet valve, and jetting a cleaning medium from the nozzle to a cleaning object.
The opening of the poppet valve can be switched between full opening and intermediate opening, and it detects when the nozzle of the lance tube rotating by the motor is facing the object to be cleaned or not. When the nozzle of the lance tube faces the object to be cleaned based on the signal from the sensor, the poppet valve is fully opened and the cleaning medium is sprayed from the nozzle, and the nozzle of the lance tube is cleaned. When the lance tube is not opposed to the object and when the lance tube is pulled out from the furnace, the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle.

  According to the present invention, since the cleaning medium flow rate can be controlled during the soot blower operation, it is possible to reduce the amount of medium injection particularly in the direction where there is no cleaning object, which is very economical.

In addition, even when the object to be cleaned (tube / coil, etc.) is moved backward, it is not necessary to spray high injection pressure and injection amount necessary for the same ash removal effect, so that steam erosion generated on the object to be cleaned is suppressed. be able to.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same location as a prior art example, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a view showing a poppet valve closed state in a poppet valve opening / closing mechanism according to the present invention, and FIG. 2 is a view showing a poppet valve open state. In either case, (a) is a front view of the poppet valve opening / closing mechanism, and (b) is a side view of the poppet valve opening / closing mechanism. In the present invention, as shown in FIGS. 1 (b) and 2 (b), a small poppet valve opening / closing cam drive motor 13 is installed in the frame 8, and a rotational drive shaft 13a of the motor 13 [FIG. )] Is connected to the opening / closing cam 14, and the cam 14 is connected to the trigger 15.

  The motor 13 rotates by a predetermined angle in response to an ON signal from the sensor to tilt the cam 14, and the trigger 15 pushes down the stem 16 to inject steam.

3 is a cross-sectional view of the poppet valve 3 showing the open / closed state of the poppet valve 3. FIG. 3 (a) is a fully opened state of the poppet valve 3, and FIG. 3 (b) is an intermediate position (intermediate opening) of the poppet valve 3. FIG. 2C shows the fully closed state of the poppet valve 3. Reference numeral 16 denotes a stem that moves up and down as the trigger 15 rotates, and is always elastically biased upward by a coil spring. A disk 17 is attached to the lower end of the stem 16. As shown in FIG. 3, the rotation amount (rotation angle) of the cam 14 is switched in three stages: fully open (a), fully closed (c), and intermediate opening (b) of the poppet valve 3. This intermediate position (b) positions the poppet valve disc 17 so as to secure the minimum amount of steam necessary to prevent the lance tube 7 inserted into the furnace 12 from being thermally deformed by the furnace gas temperature. It is set.

  That is, the poppet valve 3 is closed at the soot blower stop position, the poppet valve 3 is opened simultaneously with the insertion of the lance tube 7 into the furnace, and the intermediate position (intermediate opening degree) is determined by information on the rotational direction of the lance tube nozzle 18 during the poppet valve opening. ) And fully open.

A sensor 22 for providing information on the rotation direction of the nozzle 18 is attached to the carriage 4 that moves in accordance with the advance of the lance tube 7. As the sensor 22, a photoelectric sensor or a limit switch is used.

  The rotation state of the lance tube 7 (nozzle 18) and the relationship between the dog 21 and the sensor 22 are shown in FIG. As shown in the figure, the lance tube 7 is disposed between the tubes 19 and the lance tube 7 is continuously rotated 360 degrees in the direction of the arrow 20 (A → B → C → D → A → ..). To do. A nozzle (jet port) 18 is provided on the side surface of the lance tube 7. In FIG. 4, one nozzle 18 is provided in the circumferential direction of the lance tube 7, but two nozzles 18 may be provided at symmetrical positions in the circumferential direction of the lance tube 7.

In consideration of the rotational speed of the nozzle 18 and the traveling speed of the tube 19, a dog 21 is attached to the frame 8 in a straight line over the entire length of the frame 8 in order to turn the sensor 22 on and off at a constant distance (pitch). Yes. The carriage 4 that has started to move moves the sensor 22 on and off by the dog 21. This ON-OFF signal is taken into the motor 13 that operates the opening / closing cam 14 of the poppet valve 3, and raises and lowers the stem 16 to limit the amount of steam injected.

That is, when the sensor 22 that moves in synchronization with the rotating nozzle 18 faces the dog 21, the light emitted from the sensor 22 is reflected by the surface of the dog 21, and the reflected light is immediately received by the sensor 22 and is detected by the sensor 22. Outputs an ON signal. At this time, the nozzle 18 is in the A position or (and) the C position or in the vicinity thereof, and the nozzle 18 faces the tube 19. When the nozzle 18 rotates and the sensor 22 does not face the dog 21, the light emitted from the sensor 22 is not reflected by the surface of the dog 21, so that the sensor 22 does not receive light and the sensor 22 is turned off. At this time, the nozzle 18 is in the B position or (and) the D position which is the steam injection unnecessary range 23.

  The ON / OFF signal of the sensor 22 is taken into the motor 13 that operates the opening / closing cam 14 of the poppet valve 3 to move the stem 16 up and down, thereby limiting the amount of steam to be injected.

  Moreover, if this function is used, the amount of steam that is jetted forward and the amount of steam that is pushed backward can be changed. This is because if the ash on the surface of the target tube can be removed by the forward steam injection, the carriage 4 starts to move backward by the limit switch at the forward limit. [See FIG. 3 (b)].

  This is because the ash is removed by spraying steam with the advance of the lance tube 7 with respect to the target tube 19, but the steam is sprayed in the reverse operation as well, so the ash is removed by the forward steam injection and becomes clean. When steam is blown again onto the surface of the tube / coil, steam erosion of the tube 19 occurs. Therefore, steam erosion of the tube 19 can be suppressed by reducing the opening of the poppet valve 3 to the intermediate opening when the carriage 4 is retracted.

  There is also a method to solve this problem by shifting the pitch between the forward process and the reverse process, but the air is blown twice on the surface of the object (tube / coil) due to the spread during the injection of steam. The range is out and promotes steam erosion. In addition, it is thought that steam will not be sprayed on a clean tube if the vapor pressure is reduced and adjustment is made so that ash removal is performed by two forward and backward injection operations instead of one operation by forward injection, Actually, a significant impact pressure is required for ash removal, and it seems that ash removal will not be effective unless the receiving pressure of one spray is set high.

When the soot blower device is stopped, the limit switch at the stop position is turned ON and the poppet valve 3 is fully closed. When the soot blower device starts to move, the limit switch is turned OFF and the poppet valve 3 is fully opened. become. Thus, one limit switch is installed at the stop position.

If the poppet valve 3 is fully closed when the photoelectric sensor 22 is OFF, the soot blower installed at a position where the gas temperature is high is free from cooling steam, and the lance tube 7 may be deformed by heat. Therefore, in the present embodiment, as described above, when the photoelectric sensor 22 is OFF, the poppet valve 3 is opened to the intermediate position to flow the cooling steam to prevent thermal deformation of the lance tube 7.

Further, in the embodiment of the present invention, since the cleaned target tube 19 does not need to be cleaned when the lance tube 7 is pulled back, the poppet valve is independent of the direction of the nozzle 18 from the beginning in the pulling process of the lance tube 7. The lance tube 7 is pulled back in a state where 3 is in the intermediate position. Since the driving current of the motor that drives the lance tube 7 is reversed in the insertion process and the pull-back process of the lance tube 7, the current change is detected to determine the pull-back process of the lance tube 7, and the opening degree of the poppet valve 3 is controlled. .

  The present invention provides the soot blower body with a function of controlling the amount of steam during the operation of the soot blower, and does not stick to the installation of the poppet valve control motor or the sensor attached to the carriage.

2A and 2B are views showing a state where the poppet valve is closed in the poppet valve opening / closing mechanism according to the present invention, in which FIG. 1A is a front view of the poppet valve opening / closing mechanism, and FIG. 2B is a side view of the poppet valve opening / closing mechanism; FIG. 4 is a diagram showing a state in which the poppet valve is opened in the poppet valve opening / closing mechanism, where (a) is a front view of the poppet valve opening / closing mechanism, and (b) is a side view of the poppet valve opening / closing mechanism. It is sectional drawing which shows each state of the poppet valve. It is a figure which shows the rotation state of a lance tube, and the relationship between a sensor and a dog. It is a figure which shows the whole structure of a soot blower. It is a figure which shows the whole soot blower structure at the time of lance tube insertion. It is a figure which shows the poppet valve opening / closing mechanism by a prior art, (a) is a front view of a poppet valve opening / closing mechanism, (b) is a side view of a poppet valve opening / closing mechanism. It is a figure which shows the effective cleaning range of the soot blower installed in the suspension coil. It is a figure which shows the effective cleaning range of the soot blower installed in the horizontal coil.

Explanation of symbols

1: Wall box, 2: Roller bracket, 3: Poppet valve, 4: Carriage, 5: Drive motor, 6: Feed tube, 7: Lance tube, 8: Frame, 9: Operation box, 10: Rear support, 11: Outside the furnace, 12: Inside the furnace, 13: Motor for driving the opening / closing cam, 13a: Rotation drive shaft, 14: Poppet valve opening / closing cam, 15: Trigger, 16: Stem, 17: Disc, 18: Nozzle, 19: Target tube, 20: Direction of rotation of the lance tube, 21: Dog, 22: Photoelectric sensor, 23: Steam injection unnecessary range.

Claims (5)

A lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip;
A motor that rotationally drives the lance tube;
A poppet valve that adjusts the amount of cleaning medium fed into the lance tube;
In the soot blower device that inserts the lance tube into a furnace, sends a cleaning medium to the lance tube through the poppet valve, and injects the cleaning medium from the nozzle onto the object to be cleaned.
A sensor is provided for detecting when the nozzle of the lance tube rotated by the motor is opposed to the object to be cleaned, and the nozzle of the lance tube is to be cleaned based on a signal from the sensor. A soot blower device configured to inject a cleaning medium from the nozzle by opening the poppet valve when facing an object. 2. The soot blower apparatus according to claim 1, wherein the poppet valve is switchable to a plurality of stages of full opening, full closing, and intermediate opening. A lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip;
A motor that rotationally drives the lance tube;
A poppet valve that adjusts the amount of cleaning medium fed into the lance tube;
In the control method of the soot blower device, wherein the lance tube is inserted into a furnace, a cleaning medium is sent to the lance tube through the poppet valve, and the cleaning medium is sprayed from the nozzle onto the object to be cleaned.
The opening of the poppet valve can be switched between full opening and intermediate opening,
A sensor for detecting when the nozzle of the lance tube rotated by the motor is facing the object to be cleaned and when not facing the object to be cleaned;
When the nozzle of the lance tube faces the object to be cleaned based on the signal from the sensor, the poppet valve is fully opened and the cleaning medium is ejected from the nozzle, and the nozzle of the lance tube faces the object to be cleaned. If not, the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle. A lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip;
A motor that rotationally drives the lance tube;
A poppet valve that adjusts the amount of cleaning medium fed into the lance tube;
In the control method of the soot blower device, wherein the lance tube is inserted into a furnace, a cleaning medium is sent to the lance tube through the poppet valve, and the cleaning medium is sprayed from the nozzle onto the object to be cleaned.
The opening of the poppet valve can be switched between full opening and intermediate opening,
A sensor for detecting when the nozzle of the lance tube rotated by the motor is facing the object to be cleaned and when not facing the object to be cleaned;
Based on the signal from the sensor, when the nozzle of the lance tube faces the object to be cleaned, the poppet valve is fully opened to inject the cleaning medium from the nozzle, and when extracting the lance tube from the furnace, A control method for a soot blower device, wherein the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle. A lance tube that can be inserted into and removed from the furnace and has a nozzle at the tip;
A motor that rotationally drives the lance tube;
A poppet valve that adjusts the amount of cleaning medium fed into the lance tube;
In the control method of the soot blower device, wherein the lance tube is inserted into a furnace, a cleaning medium is sent to the lance tube through the poppet valve, and the cleaning medium is sprayed from the nozzle onto the object to be cleaned.
The opening of the poppet valve can be switched between full opening and intermediate opening,
A sensor for detecting when the nozzle of the lance tube rotated by the motor is facing the object to be cleaned and when not facing the object to be cleaned;
When the nozzle of the lance tube faces the object to be cleaned based on the signal from the sensor, the poppet valve is fully opened and the cleaning medium is ejected from the nozzle, and the nozzle of the lance tube faces the object to be cleaned. When controlling the soot blower device, the poppet valve is throttled to an intermediate opening to regulate the amount of cleaning medium injected from the nozzle when the lance tube is removed from the furnace.

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