#section6 — Public Fediverse posts

#BoilerManual #CycloneOperation #Section6 #Page23

5. When the cyclone start button is pushed the control system will check to see that all boiler, lighter and cyclone permissives have been met. Next the feeder outlet valve opens and the feeder is started. The secondary air control damper will move to its firing position. The shutoff damper will be fully open. Once windbox temperature exceeds 300 F the primary-tertiary air damper will go fully open. With a main flame detected the cyclone is successfully lit.

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#BoilerManual #CycloneOperation #Section6 #Page23

5. When the cyclone start button is pushed the control system will check to see that all boiler, lighter and cyclone permissives have been met. Next the feeder outlet valve opens and the feeder is started. The secondary air control damper will move to its firing position. The shutoff damper will be fully open. Once windbox temperature exceeds 300 F the primary-tertiary air damper will go fully open. With a main flame detected the cyclone is successfully lit.

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#BoilerManual #CycloneOperation #Section6 #Page22

Answers for cyclone operation

1. The four stages involved in cyclone startup are:

.......... 1. ___Furnace must be purged. ________________

.......... 2. ___The lighter mus be successfully ignited.______

.......... 3. ___Boiler must meet start-up conditions.________

.......... 4. ___Cyclone must be started_________________

2. Air flow is controlled by modulating the secondary air shutoff dampers, one at a time, until 25 to 30% total air flow is established. If air flow is under 25%, the dampers are opened, one at a time, until air flow is between 25 and 30% full load air flow.

3. The five boiler firing permissives necessary for cyclone startup are:

.......... 1. Boiler must be out of the trip mode.

.......... 2. Windbox-to-furnace differential pressure should be within correct limits.

.......... 3. Boiler air flow should be greater than 25% full load air flow.

.......... 4. Lighter oil pressure should be greater than 150 psi.

.......... 5. No cyclones should be in the start or stop sequence.

4. When the lighter start button is pushed the control system will first check to see that all boiler and lighter startup permissives have been met. Next, the lighter assembly is inserted and the spark probe is energized. Then, the oil valve opens, allowing oil to flow through the lighter. The oil is ignited by the energized lighter assembly, producing the flame.

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#BoilerManual #CycloneOperation #Section6 #Page22

Answers for cyclone operation

1. The four stages involved in cyclone startup are:

.......... 1. ___Furnace must be purged. ________________

.......... 2. ___The lighter mus be successfully ignited.______

.......... 3. ___Boiler must meet start-up conditions.________

.......... 4. ___Cyclone must be started_________________

2. Air flow is controlled by modulating the secondary air shutoff dampers, one at a time, until 25 to 30% total air flow is established. If air flow is under 25%, the dampers are opened, one at a time, until air flow is between 25 and 30% full load air flow.

3. The five boiler firing permissives necessary for cyclone startup are:

.......... 1. Boiler must be out of the trip mode.

.......... 2. Windbox-to-furnace differential pressure should be within correct limits.

.......... 3. Boiler air flow should be greater than 25% full load air flow.

.......... 4. Lighter oil pressure should be greater than 150 psi.

.......... 5. No cyclones should be in the start or stop sequence.

4. When the lighter start button is pushed the control system will first check to see that all boiler and lighter startup permissives have been met. Next, the lighter assembly is inserted and the spark probe is energized. Then, the oil valve opens, allowing oil to flow through the lighter. The oil is ignited by the energized lighter assembly, producing the flame.

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#BoilerManual #CycloneOperation #Section6 #Page21

Questions for cyclone operation

1. Name the four stages involved in cyclone startup.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

2. How is air flow to the boiler controlled, during the purge stage?

3. What are the five boiler firing permissives necessary for cyclone startup?

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

.......... 5. ________________________________

4. What happens in the cyclone when the lighter start button is pushed?

5. What happens in the cyclone when the cyclone start button is pushed?

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#BoilerManual #CycloneOperation #Section6 #Page21

Questions for cyclone operation

1. Name the four stages involved in cyclone startup.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

2. How is air flow to the boiler controlled, during the purge stage?

3. What are the five boiler firing permissives necessary for cyclone startup?

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

.......... 5. ________________________________

4. What happens in the cyclone when the lighter start button is pushed?

5. What happens in the cyclone when the cyclone start button is pushed?

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#BoilerManual #CycloneOperation #Section6 #Page20

There is a 5 second delay between the time the feeder stops and the feeder outlet valve closes. This allows the coal line to be clear of coal before closing the valve.

The feeder may be run manually only when the cyclone is in the test mode. Therefore, if the feeder is unloaded for maintenance purposes, the cyclone must be put in test in order to fill the feeder belt, prior to startup of the cyclone.

FLAME MONITOR

The boiler flame monitor logic continually monitors the boiler for a Fuel No Flame condition. An immediate boiler trip will occur if no flame is detected in the boiler and any cyclone is tripped. Effectively, if one cyclone is in service and it trips, an immediate boiler trip will occur. During a furnace purge, a no flame trip delay of 30 seconds will be initiated (no cyclone tripped) so that continuous boiler trips will not occur as a result of no flame detection at startup.

During normal operation if a feeder is running and main flame is not detected on that cyclone for more than 30 seconds, and unit load is less than 60%, the boiler is tripped. If a total flame-out occurs, the boiler is tripped after a 30 second time delay.

This concludes out discussion on cyclone operation. You should now be familiar with the associated equipment for cyclone firing, the controls used in this process and the various operational parameters which must be satisfied to maintain efficient operation of the system.

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#BoilerManual #CycloneOperation #Section6 #Page20

There is a 5 second delay between the time the feeder stops and the feeder outlet valve closes. This allows the coal line to be clear of coal before closing the valve.

The feeder may be run manually only when the cyclone is in the test mode. Therefore, if the feeder is unloaded for maintenance purposes, the cyclone must be put in test in order to fill the feeder belt, prior to startup of the cyclone.

FLAME MONITOR

The boiler flame monitor logic continually monitors the boiler for a Fuel No Flame condition. An immediate boiler trip will occur if no flame is detected in the boiler and any cyclone is tripped. Effectively, if one cyclone is in service and it trips, an immediate boiler trip will occur. During a furnace purge, a no flame trip delay of 30 seconds will be initiated (no cyclone tripped) so that continuous boiler trips will not occur as a result of no flame detection at startup.

During normal operation if a feeder is running and main flame is not detected on that cyclone for more than 30 seconds, and unit load is less than 60%, the boiler is tripped. If a total flame-out occurs, the boiler is tripped after a 30 second time delay.

This concludes out discussion on cyclone operation. You should now be familiar with the associated equipment for cyclone firing, the controls used in this process and the various operational parameters which must be satisfied to maintain efficient operation of the system.

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#BoilerManual #CycloneOperation #Section6 #Page19

* Feeder temperature normal.
* Cyclone jacket cooling water on.
* Coal detected at feeder inlet
* Coal detected on feeder belt (5 second delay).

The main flame monitor delay (20 seconds) begins to time when the feeder is started. During this 20 seconds, if the lighter is not successfully lit, the cyclone will trip. At the end of the time delay, if a main flame is not detected the cyclone will trip. Also, at the end of the 20 second time delay, the primary/tertiary air and secondary air shutoff dampers and feeder outlet valve are checked for proper position. If an of these devices are not at the proper position for longer than 10 seconds, the cyclone will trip.

The lighter will remain in service at least five minutes after the cyclone is successfully lit. The Main Flame light will light white when a main flame is being detected.

The Cyclone Trouble light will flash amber when a cyclone trouble alarm is present. The pushbutton, when depressed, acknowledges the alarm and changes the flashing alarm to a steady indication.

When the cyclone is not successfully lit, the analog control for thte feeder and the secondary air velocity damper are commanded to light off. Once the cyclone becomes successfully lit, the analog controls are released to set the firing rate of the cyclone.

When the cyclone is stopped or tripped, it will go into the following shutdown sequence:

1. Feeder stops.
2. Feeder outlet valve closes.
3. Lighter shutdown.

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#BoilerManual #CycloneOperation #Section6 #Page19

* Feeder temperature normal.
* Cyclone jacket cooling water on.
* Coal detected at feeder inlet
* Coal detected on feeder belt (5 second delay).

The main flame monitor delay (20 seconds) begins to time when the feeder is started. During this 20 seconds, if the lighter is not successfully lit, the cyclone will trip. At the end of the time delay, if a main flame is not detected the cyclone will trip. Also, at the end of the 20 second time delay, the primary/tertiary air and secondary air shutoff dampers and feeder outlet valve are checked for proper position. If an of these devices are not at the proper position for longer than 10 seconds, the cyclone will trip.

The lighter will remain in service at least five minutes after the cyclone is successfully lit. The Main Flame light will light white when a main flame is being detected.

The Cyclone Trouble light will flash amber when a cyclone trouble alarm is present. The pushbutton, when depressed, acknowledges the alarm and changes the flashing alarm to a steady indication.

When the cyclone is not successfully lit, the analog control for thte feeder and the secondary air velocity damper are commanded to light off. Once the cyclone becomes successfully lit, the analog controls are released to set the firing rate of the cyclone.

When the cyclone is stopped or tripped, it will go into the following shutdown sequence:

1. Feeder stops.
2. Feeder outlet valve closes.
3. Lighter shutdown.

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#BoilerManual #CycloneOperation #Section6 #Page18

temperature. The primary/tertiary air shutoff damper will go to fully open at a windbox temperature greater than 300 F.

A Maintained lighter may only be initiated when the cyclone is off management. In order to start a maintained lighter when the cyclone is on management, the operator must take the cyclone off management, start the lighter via Lighter Start push button, and transfer the cyclone back on management. The Lighter Start pushbutton will backlight red.

If a cyclone stop is commanded by the computer while the cyclone is On Management and Maintained lighter is in service, the lighter is shutdown along with the cyclone.

To reset a lighter trip, depress the Lighter Stop pushbutton. It will backlight green when the stop command has been memorized.

The Lighter Trouble indicator will flash amber when a lighter trouble alarm is present. The pushbutton, when depressed, acknowledges the alarm and changes the flashing alarm to a steady indication.

CYCLONE COAL MONITOR

If a cyclone remains in a start or stop sequence for longer than one minute, sequence monitoring will be required. At the end of one minute if the cyclone is started but not successfully lit, or stopped and not successfully shutdown, the cyclone will be tripped.

Monitoring of the cyclone begins when the feeder starts. If when the feeder starts the following permissives are not met, the cyclone will trip.

* Feeder pressurized
* Feeder outlet valve opened.
* Feeder inlet valve opened.

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#BoilerManual #CycloneOperation #Section6 #Page18

temperature. The primary/tertiary air shutoff damper will go to fully open at a windbox temperature greater than 300 F.

A Maintained lighter may only be initiated when the cyclone is off management. In order to start a maintained lighter when the cyclone is on management, the operator must take the cyclone off management, start the lighter via Lighter Start push button, and transfer the cyclone back on management. The Lighter Start pushbutton will backlight red.

If a cyclone stop is commanded by the computer while the cyclone is On Management and Maintained lighter is in service, the lighter is shutdown along with the cyclone.

To reset a lighter trip, depress the Lighter Stop pushbutton. It will backlight green when the stop command has been memorized.

The Lighter Trouble indicator will flash amber when a lighter trouble alarm is present. The pushbutton, when depressed, acknowledges the alarm and changes the flashing alarm to a steady indication.

CYCLONE COAL MONITOR

If a cyclone remains in a start or stop sequence for longer than one minute, sequence monitoring will be required. At the end of one minute if the cyclone is started but not successfully lit, or stopped and not successfully shutdown, the cyclone will be tripped.

Monitoring of the cyclone begins when the feeder starts. If when the feeder starts the following permissives are not met, the cyclone will trip.

* Feeder pressurized
* Feeder outlet valve opened.
* Feeder inlet valve opened.

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#BoilerManual #CycloneOperation #Section6 #Page17

* Cyclone jacket cooling water on.
* Cyclone and lighter trips reset.

When the lighter is required by the cyclone sequence and all permissives are met, the Lighter Ready indicating light is lit.

CYCLONE START SEQUENCE

With the permissives for the boiler, cyclone and lighters satisfied, the cyclone start may be initiated. Depress the Cyclone Start pushbutton, it will backlight red.

With the initiation of the Cyclone Start pushbutton, the start lighter sequence can begin. When the Lighter Start pushbutton is depressed, the lighter assembly will be inserted and the high energy probe energized by the ignition transformer. After a purge delay, the oil valve is opened. At this point a 5 second lighter flame monitor delay will begin. When the delay times out, the secondary air shutoff damper must be at lightoff or above. Also, the primary/tertiary air damper must be open, the lighter must be inserted, and a lighter flame must be detected. With these conditions satisfied, the lighter is successfully lit.

Once the lighter is successfully lit, the Lighter On indicator will backlight red. When a lighter flame is being detected, the white Lighter Flame indicator is lit. {A note about the flame detectors--the naked eye can be fooled into thinking a lighter is lit when it is not just because the eye is likely blinded by other successfully lit cyclones, so an instrument is used incorporating a vacuum tube type detector manufactured by FyrEye...I hope I remember the spelling correctly.}

Following Lighter Successful the coal feeder may be started if the feeder outlet valve is open. Once the feeder speed exceeds 25%, the secondary air control damper will move to the firing position. The secondary air shutoff damper will be fully open. The primary/tertiary air shutoff damper will be at light off or fully open, depending on the windbox

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#BoilerManual #CycloneOperation #Section6 #Page17

* Cyclone jacket cooling water on.
* Cyclone and lighter trips reset.

When the lighter is required by the cyclone sequence and all permissives are met, the Lighter Ready indicating light is lit.

CYCLONE START SEQUENCE

With the permissives for the boiler, cyclone and lighters satisfied, the cyclone start may be initiated. Depress the Cyclone Start pushbutton, it will backlight red.

With the initiation of the Cyclone Start pushbutton, the start lighter sequence can begin. When the Lighter Start pushbutton is depressed, the lighter assembly will be inserted and the high energy probe energized by the ignition transformer. After a purge delay, the oil valve is opened. At this point a 5 second lighter flame monitor delay will begin. When the delay times out, the secondary air shutoff damper must be at lightoff or above. Also, the primary/tertiary air damper must be open, the lighter must be inserted, and a lighter flame must be detected. With these conditions satisfied, the lighter is successfully lit.

Once the lighter is successfully lit, the Lighter On indicator will backlight red. When a lighter flame is being detected, the white Lighter Flame indicator is lit. {A note about the flame detectors--the naked eye can be fooled into thinking a lighter is lit when it is not just because the eye is likely blinded by other successfully lit cyclones, so an instrument is used incorporating a vacuum tube type detector manufactured by FyrEye...I hope I remember the spelling correctly.}

Following Lighter Successful the coal feeder may be started if the feeder outlet valve is open. Once the feeder speed exceeds 25%, the secondary air control damper will move to the firing position. The secondary air shutoff damper will be fully open. The primary/tertiary air shutoff damper will be at light off or fully open, depending on the windbox

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#BoilerManual #CycloneOperation #Section6 #Page16

CYCLONE FIRING PERMISSIVES

The common firing permissives as well as the individual cyclone firing permissives must be satisfied in order to start a cyclone. The common firing permissives are the same as the boiler firing permissives. The individual cyclone firing permissives are as follows:

* Lighter and cyclone trips reset.
* Cyclone enabled.
* Feeder speed and velocity control damper set to light off.
* Feeder switch in remote.
* Feeder outlet valve closed.
* Feeder inlet valve open.
* Coal detected at feeder inlet (secoal).
* Feeder off.
* Feeder temperature normal.
* Feeder pressurized.
* Cyclone jacket cooling water on.
* Lighter successfully lit.

If all these permissives are satisfied, the red Cyclone Ready indicating light on the cyclone control panel will be lit.

LIGHTER

The lighter permissives again integrate the common (boiler firing) as well as the individual lighter permissives. The individual lighter permissives include:

* Lighter oil valve closed.
* Lighter retracted.
* Cyclone successfully lit or shutdown.

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#BoilerManual #CycloneOperation #Section6 #Page16

CYCLONE FIRING PERMISSIVES

The common firing permissives as well as the individual cyclone firing permissives must be satisfied in order to start a cyclone. The common firing permissives are the same as the boiler firing permissives. The individual cyclone firing permissives are as follows:

* Lighter and cyclone trips reset.
* Cyclone enabled.
* Feeder speed and velocity control damper set to light off.
* Feeder switch in remote.
* Feeder outlet valve closed.
* Feeder inlet valve open.
* Coal detected at feeder inlet (secoal).
* Feeder off.
* Feeder temperature normal.
* Feeder pressurized.
* Cyclone jacket cooling water on.
* Lighter successfully lit.

If all these permissives are satisfied, the red Cyclone Ready indicating light on the cyclone control panel will be lit.

LIGHTER

The lighter permissives again integrate the common (boiler firing) as well as the individual lighter permissives. The individual lighter permissives include:

* Lighter oil valve closed.
* Lighter retracted.
* Cyclone successfully lit or shutdown.

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#BoilerManual #CycloneOperation #Section6 #Page15

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Alt = Notes I made on the page: B7 STOP =Either A1 or A6 or both
A1 STOP = A6 only
A6 STOP = A1 only
This image is of a complex flow chart marked Sequece 4 with the number circled; also marked BOILER AIR FLOW DAMPER MANAGEMENT. It uses Cyclone A5 as the beginning of logic that applies to all cyclones in the sequence covered in the main text, but a label in the center of the chart reads "SAME FOR ALL CYCLONES" as it points to the points in the logic flow Cyclone successful yes/no at the top side and also to the bottom side at the point that reads "Delay timed out? yes".

#BoilerManual #CycloneOperation #Section6 #Page15

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Alt = Notes I made on the page: B7 STOP =Either A1 or A6 or both
A1 STOP = A6 only
A6 STOP = A1 only
This image is of a complex flow chart marked Sequece 4 with the number circled; also marked BOILER AIR FLOW DAMPER MANAGEMENT. It uses Cyclone A5 as the beginning of logic that applies to all cyclones in the sequence covered in the main text, but a label in the center of the chart reads "SAME FOR ALL CYCLONES" as it points to the points in the logic flow Cyclone successful yes/no at the top side and also to the bottom side at the point that reads "Delay timed out? yes".

#BoilerManual #CycloneOperation #Section6 #Page14

BOILER AIR FLOW DAMPER CONTROL

One minute after a boiler trip, the secondary air shutoff dampers are commanded to light-off. With all cyclone shutoff dampers and control dampers open (including the flue gas recirculation system), the FD and ID fan inlet vanes are opened, until boiler air flow is 25-30% of full load air flow. The air flow is maintained for not less than 5 minutes, to complete the purge cycle.

Whenever the boiler is not tripped, the system will try to maintain boiler air flow between 25% and 30%.

If total boiler air flow is greater than 30%, the damper control scheme, Sequence 4, will initiate a close signal to the secondary air damper controller beginning with cyclone B6. After a 10 second time delay (T.D.O.) if the total air flow is still greater than 30%, the secondary air damper on cyclone A2 will begin to close. Subsequently a 10 second time delay will initiate a close command to the next cyclone (B2) and the next (A6) and so forth until the air flow goes below 30%. The remaining cyclone damper controls will time out. If

the air flow is below 25%, the same procedure is followed with the only difference being the dampers are opened rather than closed.

If after cycling through all the cyclones a demand signal still exists, whether for more or less air flow, an alarm will be annunciated. If air flow is greater than 30%, the annunciator indicates available dampers closed. If the air flow is less than 25% the annunciator indicates available dampers open. {A word about annunciators--you'd expect those to be in the control room, but they're actually elsewhere and at Baldwin, a company called Sentry made units that had large white, labeled lights to go with the alarms.}

Note: When unit load is above 30%, the alarm available dampers closed will be present.

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#BoilerManual #CycloneOperation #Section6 #Page14

BOILER AIR FLOW DAMPER CONTROL

One minute after a boiler trip, the secondary air shutoff dampers are commanded to light-off. With all cyclone shutoff dampers and control dampers open (including the flue gas recirculation system), the FD and ID fan inlet vanes are opened, until boiler air flow is 25-30% of full load air flow. The air flow is maintained for not less than 5 minutes, to complete the purge cycle.

Whenever the boiler is not tripped, the system will try to maintain boiler air flow between 25% and 30%.

If total boiler air flow is greater than 30%, the damper control scheme, Sequence 4, will initiate a close signal to the secondary air damper controller beginning with cyclone B6. After a 10 second time delay (T.D.O.) if the total air flow is still greater than 30%, the secondary air damper on cyclone A2 will begin to close. Subsequently a 10 second time delay will initiate a close command to the next cyclone (B2) and the next (A6) and so forth until the air flow goes below 30%. The remaining cyclone damper controls will time out. If

the air flow is below 25%, the same procedure is followed with the only difference being the dampers are opened rather than closed.

If after cycling through all the cyclones a demand signal still exists, whether for more or less air flow, an alarm will be annunciated. If air flow is greater than 30%, the annunciator indicates available dampers closed. If the air flow is less than 25% the annunciator indicates available dampers open. {A word about annunciators--you'd expect those to be in the control room, but they're actually elsewhere and at Baldwin, a company called Sentry made units that had large white, labeled lights to go with the alarms.}

Note: When unit load is above 30%, the alarm available dampers closed will be present.

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#BoilerManual #CycloneOperation #Section6 #Page13

BOILER FIRING AND PURGE PERMISSIVES

The boiler firing permissives are the conditions common to all cyclones that must be

satisfied before firing is permitted in the boiler; they are:

* Boiler NOT in trip mode.
* The windbox to furnace differential is within limits.
* Boiler air flow is equal to or greater than 25%.
* Lighter oil pressure is greater than 150 psi.
* No other cyclone is i the start or stop sequence.

If a boiler trip has occurred, the control system memory will be set to the trip side. The memory may be reset only when purge is complete and boiler trip contact is no longer closed. The boiler purge sequence is as follows:

* Lighter fuel oil shutoff valves closed.
* Lighter fuel oil vent valve open.
* All lighter oil valves closed.

* Feeders off.
* Cyclone valve closed.
* Circulation valve closed.
* 2 out of 3 gas recirculation fans on with shutoff dampers open.
* Gas recirculation control dampers and gas tempering control dampers not closed.
* 1 out of 3 FD fans on.
* 1 out of 3 ID fans on.
* Air flow greater than 25%
* Windbox to furnace differential delta-P greater than 10" H2O.

When all of the above conditions have been satisfied continuously for five minutes, the purge is complete.

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#BoilerManual #CycloneOperation #Section6 #Page13

BOILER FIRING AND PURGE PERMISSIVES

The boiler firing permissives are the conditions common to all cyclones that must be

satisfied before firing is permitted in the boiler; they are:

* Boiler NOT in trip mode.
* The windbox to furnace differential is within limits.
* Boiler air flow is equal to or greater than 25%.
* Lighter oil pressure is greater than 150 psi.
* No other cyclone is i the start or stop sequence.

If a boiler trip has occurred, the control system memory will be set to the trip side. The memory may be reset only when purge is complete and boiler trip contact is no longer closed. The boiler purge sequence is as follows:

* Lighter fuel oil shutoff valves closed.
* Lighter fuel oil vent valve open.
* All lighter oil valves closed.

* Feeders off.
* Cyclone valve closed.
* Circulation valve closed.
* 2 out of 3 gas recirculation fans on with shutoff dampers open.
* Gas recirculation control dampers and gas tempering control dampers not closed.
* 1 out of 3 FD fans on.
* 1 out of 3 ID fans on.
* Air flow greater than 25%
* Windbox to furnace differential delta-P greater than 10" H2O.

When all of the above conditions have been satisfied continuously for five minutes, the purge is complete.

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#BoilerManual #CycloneOperation #Section6 #Page12

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Alt = Image containing 3 logic flow charts inside of one frame. Each, in turn, is marked Sequence 1 with the number circled, marked SYSTEM POWER; Sequence 2 with the number circled, marked CYCLONE MANAGEMENT ON/OFF; Sequence 3 with the number circled, marked CYCLONE ENABLE/TEST MODE. These flow charts simply illustrate the wording in the main text which refers to them.

#BoilerManual #CycloneOperation #Section6 #Page12

------------------------------------------------- 12 ------------------------------------------------------
Alt = Image containing 3 logic flow charts inside of one frame. Each, in turn, is marked Sequence 1 with the number circled, marked SYSTEM POWER; Sequence 2 with the number circled, marked CYCLONE MANAGEMENT ON/OFF; Sequence 3 with the number circled, marked CYCLONE ENABLE/TEST MODE. These flow charts simply illustrate the wording in the main text which refers to them.

#BoilerManual #CycloneOperation #Section6 #Page11

Sequence 2, conditions for transferring the cyclone on or off management, are as follows:

Requirements:

1. Cyclone not tripped.

2. Cyclone not in test.

3. System in operate and management on.

4. Cyclone not selected management off.

To transfer the cyclone on to management, depress the Management On pushbutton. The red Select light will backlight red. The lower field will backlight red when the cyclone is on management.

The same process is followed for cyclone Management Off. However, it will be indicated with a green backlight.

Sequence 3 shows the requirements for transferring a cyclone into the enable or test mode, the cyclone is disabled so that its logic may respond to inputs from the test panel, but at the same time will not affect the condition of controlled devices. A single cyclone can be in the test mode while the other cyclones are in the operate mode, but a permissive for selecting the test mode is that the logic be in the shutdown state.

Requirements: Cyclone Enabled

1. System in operate.

2. Cyclone stopped and successfully shutdown.

3. Cyclone disabled not required.

With the requirements satisfied, the cyclone enable mode is established automatically. Anytime the cyclone is in the enabled mode and the system is in operate, the cyclone trip monitor will be on.

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#BoilerManual #CycloneOperation #Section6 #Page11

Sequence 2, conditions for transferring the cyclone on or off management, are as follows:

Requirements:

1. Cyclone not tripped.

2. Cyclone not in test.

3. System in operate and management on.

4. Cyclone not selected management off.

To transfer the cyclone on to management, depress the Management On pushbutton. The red Select light will backlight red. The lower field will backlight red when the cyclone is on management.

The same process is followed for cyclone Management Off. However, it will be indicated with a green backlight.

Sequence 3 shows the requirements for transferring a cyclone into the enable or test mode, the cyclone is disabled so that its logic may respond to inputs from the test panel, but at the same time will not affect the condition of controlled devices. A single cyclone can be in the test mode while the other cyclones are in the operate mode, but a permissive for selecting the test mode is that the logic be in the shutdown state.

Requirements: Cyclone Enabled

1. System in operate.

2. Cyclone stopped and successfully shutdown.

3. Cyclone disabled not required.

With the requirements satisfied, the cyclone enable mode is established automatically. Anytime the cyclone is in the enabled mode and the system is in operate, the cyclone trip monitor will be on.

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#BoilerManual #CycloneOperation #Section6 #Page10

------------------------------------------------- 10 ------------------------------------------------------
Alt = Labeled Fig. 4 Cyclone test panel. The image is sideways with the bottom along the right edge and the top along the left edge. This image is a drawn rendering of the front of a rack-mountable box with vertical handles, one on the right and one on the left.
At the top center of the box is marked TEST PANEL. In the middle is a large rotary switch pointer, halfway surrounded by small squares indicating 9 possible positions to the right of the switch. The top position is marked Idle Damper and the switch appears to be engaged with that position. To the left of the switch are 3 columns of toggle switches and round lights marked LIGHTER. The column to the right of the switch is labeled CYCLONE with 3 columns of toggle switches and round lights, but at the top of the column it has one less light than the left hand column.
Between the two columns, below the rotary switch, are three lamps marked Transformer, Lighter on and Cyclone on. Between the two columns, above the rotary switch, are one toggle switch marked Trip, and two lights each marked Open/close, and Trouble respectively.

The left column of lights and switches under the LIGHTER label are, in top down order:
leftmost column are lights marked Ready, Close, Close, then a toggle marked Ltr. press. > 150 psi, then a light marked Stop, then a toggle marked Oil valve.
Middle column has lights, one unmarked below the LIGHTER label, Pri. Damper, Sec. Damper, then a toggle marked Air flow > 30%, then a toggle marked Lighter, then a toggle marked Lighter flame.The rightmost column under LIGHTER is all lights, marked in top-down order: Pri. air cold, Open, Open, Sec. air L.O., Start, and Flame.

The right hand column of lights and switches under the CYCLONE label are, in top down order:
left column consists of 3 lights and two toggles, labeled from top down, Closed, Stop, Trouble acking {sic}, Feeder speed > 24%, Jacket flow;
middle column has one light under the CYCLONE label, then the remainder are toggle switches marked, top down: Feeder out valve, Feeder, Main flame, Air temp. > 300 F, and Feeder in valve;
rightmost column are the lights labeled Ready, Open, Start, Established, then two toggles labeled Feeder unload and Coal on belt.

#BoilerManual #CycloneOperation #Section6 #Page10

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Alt = Labeled Fig. 4 Cyclone test panel. The image is sideways with the bottom along the right edge and the top along the left edge. This image is a drawn rendering of the front of a rack-mountable box with vertical handles, one on the right and one on the left.
At the top center of the box is marked TEST PANEL. In the middle is a large rotary switch pointer, halfway surrounded by small squares indicating 9 possible positions to the right of the switch. The top position is marked Idle Damper and the switch appears to be engaged with that position. To the left of the switch are 3 columns of toggle switches and round lights marked LIGHTER. The column to the right of the switch is labeled CYCLONE with 3 columns of toggle switches and round lights, but at the top of the column it has one less light than the left hand column.
Between the two columns, below the rotary switch, are three lamps marked Transformer, Lighter on and Cyclone on. Between the two columns, above the rotary switch, are one toggle switch marked Trip, and two lights each marked Open/close, and Trouble respectively.

The left column of lights and switches under the LIGHTER label are, in top down order:
leftmost column are lights marked Ready, Close, Close, then a toggle marked Ltr. press. > 150 psi, then a light marked Stop, then a toggle marked Oil valve.
Middle column has lights, one unmarked below the LIGHTER label, Pri. Damper, Sec. Damper, then a toggle marked Air flow > 30%, then a toggle marked Lighter, then a toggle marked Lighter flame.The rightmost column under LIGHTER is all lights, marked in top-down order: Pri. air cold, Open, Open, Sec. air L.O., Start, and Flame.

The right hand column of lights and switches under the CYCLONE label are, in top down order:
left column consists of 3 lights and two toggles, labeled from top down, Closed, Stop, Trouble acking {sic}, Feeder speed > 24%, Jacket flow;
middle column has one light under the CYCLONE label, then the remainder are toggle switches marked, top down: Feeder out valve, Feeder, Main flame, Air temp. > 300 F, and Feeder in valve;
rightmost column are the lights labeled Ready, Open, Start, Established, then two toggles labeled Feeder unload and Coal on belt.

#BoilerManual #CycloneOperation #Section6 #Page9

Operate/test Cyclone (#)
Includes 14 two-position toggle switches, one per cyclone. When in the test position, the inputs and outputs to the control logic are removed from the cyclone to permit testing. Inoperate the control inputs and outputs are reconnected to the associated cyclone. Cyclones may be transferred in or out of test only when that cyclone is successfully shutdown.

Operate Cyclone (#)
Includes 14 indicating lights (one per cyclone) next to its associated operator/test switch. When lit, these lights indicate which cyclone is in the operate mode.

d) Test Panel
The cyclone test panel, Figure 4, located in systems cabinet four serves dual purposes. When the cyclone operate/test switch is in the operate position (Cyclone Operate light lit) the lights on the test panel reflect the actual condition of the logic for the selected cyclone. When in the test position(Cyclone Operate light is not lit) the lights on the test panel reflect the condition of the logic being tested. The toggle switches on the cyclone test panel are used to simulate burner front conditions during a cyclone test. When in the operate mode,the toggle switches on the test panel are ineffective.

The following sequences illustrate thte system logic which takes place in the Logic Cabinets.

Sequence 1 shows the system's reaction to a loss of resumption of power. When a total loss of power occurs, a boiler trip is required. On resumption of power the system outputs become active 5 seconds after power is resumed. Following the activation of the system outputs, there is a 20 second delay while the system is being monitored. Once the system monitor delay times out, the system is in the operator mode with the boiler trip monitor on.

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#BoilerManual #CycloneOperation #Section6 #Page9

Operate/test Cyclone (#)
Includes 14 two-position toggle switches, one per cyclone. When in the test position, the inputs and outputs to the control logic are removed from the cyclone to permit testing. Inoperate the control inputs and outputs are reconnected to the associated cyclone. Cyclones may be transferred in or out of test only when that cyclone is successfully shutdown.

Operate Cyclone (#)
Includes 14 indicating lights (one per cyclone) next to its associated operator/test switch. When lit, these lights indicate which cyclone is in the operate mode.

d) Test Panel
The cyclone test panel, Figure 4, located in systems cabinet four serves dual purposes. When the cyclone operate/test switch is in the operate position (Cyclone Operate light lit) the lights on the test panel reflect the actual condition of the logic for the selected cyclone. When in the test position(Cyclone Operate light is not lit) the lights on the test panel reflect the condition of the logic being tested. The toggle switches on the cyclone test panel are used to simulate burner front conditions during a cyclone test. When in the operate mode,the toggle switches on the test panel are ineffective.

The following sequences illustrate thte system logic which takes place in the Logic Cabinets.

Sequence 1 shows the system's reaction to a loss of resumption of power. When a total loss of power occurs, a boiler trip is required. On resumption of power the system outputs become active 5 seconds after power is resumed. Following the activation of the system outputs, there is a 20 second delay while the system is being monitored. Once the system monitor delay times out, the system is in the operator mode with the boiler trip monitor on.

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#BoilerManual #CycloneOperation #Section6 #Page8

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Alt = Labeled Fig. 3 Cyclone control station. Similar to Fig. 2 on the previous page, switches and indicator lamps are depicted but in 2 columns of 6 each. Left column is marked Status; right column is marked Control. In the left column, at the top, is indicator marked Test; the indicator under that is laterally divided in half with the top half marked Lighter flame and the bottom half marked Main flame; below that is an indicator marked Lighter ON; the one below that is designated a pushbutton switch, marked Lighter trouble; below that is an indicator marked Cyclone ON, and below that is the last one in the column, designated a pushbutton switch, marked Cyclone trouble.

In the right column, at the top, is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Select and the bottom half marked Management ON; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Select and the bottom half marked Management OFF; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Lighter ready and the bottom half marked Lighter start; the one below that is designated a pushbutton switch, marked Lighter Stop; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Cyclone ready and the bottom half marked Cyclone start; The bottom most indicator is designated to be a pushbutton switch and is marked Cyclone stop.

#BoilerManual #CycloneOperation #Section6 #Page8

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Alt = Labeled Fig. 3 Cyclone control station. Similar to Fig. 2 on the previous page, switches and indicator lamps are depicted but in 2 columns of 6 each. Left column is marked Status; right column is marked Control. In the left column, at the top, is indicator marked Test; the indicator under that is laterally divided in half with the top half marked Lighter flame and the bottom half marked Main flame; below that is an indicator marked Lighter ON; the one below that is designated a pushbutton switch, marked Lighter trouble; below that is an indicator marked Cyclone ON, and below that is the last one in the column, designated a pushbutton switch, marked Cyclone trouble.

In the right column, at the top, is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Select and the bottom half marked Management ON; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Select and the bottom half marked Management OFF; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Lighter ready and the bottom half marked Lighter start; the one below that is designated a pushbutton switch, marked Lighter Stop; below that is an indicator laterally divided in half and designated a pushbutton switch, with the top half marked Cyclone ready and the bottom half marked Cyclone start; The bottom most indicator is designated to be a pushbutton switch and is marked Cyclone stop.

#BoilerManual #CycloneOperation #Section6 #Page7

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Alt = Labeled Fig. 2 Remote common station. Image looks like a column of 6 framed oblong boxes topped by a flattened arch, representing 2 pushbutton switches at the top of the column and the remainder being indicating lights. There are no labels on the lighted oblongs but the top two designated switches are labeled, in top down order, System management ON; System management OFF. They're designated by a diagonal line across the lower right corner of each, and at the bottom of the column it reads "/Slanted line denotes pushbutton"

#BoilerManual #CycloneOperation #Section6 #Page7

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Alt = Labeled Fig. 2 Remote common station. Image looks like a column of 6 framed oblong boxes topped by a flattened arch, representing 2 pushbutton switches at the top of the column and the remainder being indicating lights. There are no labels on the lighted oblongs but the top two designated switches are labeled, in top down order, System management ON; System management OFF. They're designated by a diagonal line across the lower right corner of each, and at the bottom of the column it reads "/Slanted line denotes pushbutton"

#BoilerManual #CycloneOperation #Section6 #Page6

1. Conditions of burner equipment, such as the open or closed position of a damper.

2. Conditions of devices within the system, such as the operation of a delay timer.

3. Conditions of operator controls, such as the initiation of the start of a cyclone.

The logic diagrams which follow are simplified versions of the reasoning process by which the burner control system arrives at its decisions and either initiates an action or communicates to the operator, or both. Each path represents a train of thought, taking into consideration factors which will affect its conclusion. The system may be divided into two general categories of equipment: operator controls and logic cabinets.

The Operator Controls consist of the following items:

a) Remote Common Station
The remote common station, Figure 2, consists of one pushbutton module, located in the control room.

b) Remote Cyclone Station
Each cyclone control station, Figure 3, contains two pushbutton modules, located in the control room.

c) Test Switches and Indicators
The following switches and indicators are on a per cyclone basis. They are located in systems cabinet four.

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#BoilerManual #CycloneOperation #Section6 #Page6

1. Conditions of burner equipment, such as the open or closed position of a damper.

2. Conditions of devices within the system, such as the operation of a delay timer.

3. Conditions of operator controls, such as the initiation of the start of a cyclone.

The logic diagrams which follow are simplified versions of the reasoning process by which the burner control system arrives at its decisions and either initiates an action or communicates to the operator, or both. Each path represents a train of thought, taking into consideration factors which will affect its conclusion. The system may be divided into two general categories of equipment: operator controls and logic cabinets.

The Operator Controls consist of the following items:

a) Remote Common Station
The remote common station, Figure 2, consists of one pushbutton module, located in the control room.

b) Remote Cyclone Station
Each cyclone control station, Figure 3, contains two pushbutton modules, located in the control room.

c) Test Switches and Indicators
The following switches and indicators are on a per cyclone basis. They are located in systems cabinet four.

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#BoilerManual #CycloneOperation #Section6 #Page5

To ensure that sufficient air flow is provided to completely burn the fuel being fired, the requirement for air flow is increased whenever the measured fuel exceeds its requirement. The cyclone fuel requirement is compared with the measured total cyclone air flow which has been temperature compensated and calibrated for excess air requirements. Any difference will cause the Individual cyclone Air Flow Controls to reposition the velocity damper (secondary air flow control damper) until the measured cyclone air flow satisfies its requirement. A selector station is required for each cyclone to permit selection of automatic or manual operation of the velocity damper when desired.

Total Air Flow ControlAs the cyclone fuel loading increases, more air flow is obtained by opening the individual cyclone velocity dampers. The windbox to furnace differential setpoint may be varied from 30.5 to 32.5" H2O. An adjustable setpoint is provided to permit the operator to change the setpoint when desired. The Air Flow Control modulates the forced draft fan flow control to obtain the desired windbox to furnace delta-P.

The total air flow is then adjusted to obtain the desired flue gas O2 as measured at the economizer outlet.

BURNER OPERATION

The Bailey Control system continuously determines conditions pertinent to control of burner operation, then takes action based on three conditions. Conditions which must be recognized may be classified as follows:

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#BoilerManual #CycloneOperation #Section6 #Page5

To ensure that sufficient air flow is provided to completely burn the fuel being fired, the requirement for air flow is increased whenever the measured fuel exceeds its requirement. The cyclone fuel requirement is compared with the measured total cyclone air flow which has been temperature compensated and calibrated for excess air requirements. Any difference will cause the Individual cyclone Air Flow Controls to reposition the velocity damper (secondary air flow control damper) until the measured cyclone air flow satisfies its requirement. A selector station is required for each cyclone to permit selection of automatic or manual operation of the velocity damper when desired.

Total Air Flow ControlAs the cyclone fuel loading increases, more air flow is obtained by opening the individual cyclone velocity dampers. The windbox to furnace differential setpoint may be varied from 30.5 to 32.5" H2O. An adjustable setpoint is provided to permit the operator to change the setpoint when desired. The Air Flow Control modulates the forced draft fan flow control to obtain the desired windbox to furnace delta-P.

The total air flow is then adjusted to obtain the desired flue gas O2 as measured at the economizer outlet.

BURNER OPERATION

The Bailey Control system continuously determines conditions pertinent to control of burner operation, then takes action based on three conditions. Conditions which must be recognized may be classified as follows:

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#BoilerManual #CycloneOperation #Section6 #Page4

FUEL FLOW CONTROL

The measured fuel flow from individual cyclones is totaled and compared with the total fuel required. Any difference is corrected by changing the total fuel flow control on the cyclones in-service (on automatic).

The individual cyclone fuel flow must be controlled to maintain sufficient heat input to each cyclone to ensure that the slag remains in a molten condition so it will tap.

Individual Cyclone Fuel Flow Control

A manual bias is provided for each cyclone to permit an individual cyclone to carry more or less load with respect to the other cyclones. To insure that sufficient air is always available for burning the fuel safely, the cyclone fuel requirement is limited whenever the measured air flow fails to meet its requirement. Fuel flow to each cyclone is regulated by a variable speed gravimetric coal feeder. {Both the gravimetric and volumetric coal feeders required re-calibration by the C & I Department. This department had a book of listed routine assignments in addition to repair/replace function.} A selector station for each cyclone permits the operator to select automatic or to manually control the coal feeder speed when desired.

AIR FLOW CONTROL

The cyclone fuel requirement serves as the basis for individual cyclone air flow requirement. The Air Flow Control is designed to produce the correct air flow to satisfy the boiler requirements for total air while simultaneously ensuring that sufficient air flow is available for each cyclone in service. Provision is made to enable the air flow to lag its requirement both when the load is being decreased normally and following a unit trip.

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#BoilerManual #CycloneOperation #Section6 #Page4

FUEL FLOW CONTROL

The measured fuel flow from individual cyclones is totaled and compared with the total fuel required. Any difference is corrected by changing the total fuel flow control on the cyclones in-service (on automatic).

The individual cyclone fuel flow must be controlled to maintain sufficient heat input to each cyclone to ensure that the slag remains in a molten condition so it will tap.

Individual Cyclone Fuel Flow Control

A manual bias is provided for each cyclone to permit an individual cyclone to carry more or less load with respect to the other cyclones. To insure that sufficient air is always available for burning the fuel safely, the cyclone fuel requirement is limited whenever the measured air flow fails to meet its requirement. Fuel flow to each cyclone is regulated by a variable speed gravimetric coal feeder. {Both the gravimetric and volumetric coal feeders required re-calibration by the C & I Department. This department had a book of listed routine assignments in addition to repair/replace function.} A selector station for each cyclone permits the operator to select automatic or to manually control the coal feeder speed when desired.

AIR FLOW CONTROL

The cyclone fuel requirement serves as the basis for individual cyclone air flow requirement. The Air Flow Control is designed to produce the correct air flow to satisfy the boiler requirements for total air while simultaneously ensuring that sufficient air flow is available for each cyclone in service. Provision is made to enable the air flow to lag its requirement both when the load is being decreased normally and following a unit trip.

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#BoilerManual #CycloneOperation #Section6 #Page3

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Alt = Image of a complex logic diagram is sideways with the bottom along the right edge and top along the left edge. Labeled Fig. 1 Fuel and air flow control--cyclone firing. Label is off to the bottom right of the diagram.

#BoilerManual #CycloneOperation #Section6 #Page3

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Alt = Image of a complex logic diagram is sideways with the bottom along the right edge and top along the left edge. Labeled Fig. 1 Fuel and air flow control--cyclone firing. Label is off to the bottom right of the diagram.

#BoilerManual #CycloneOperation #Section6 #Page2

time for the lighter flame. This control also shuts the lighter off when it is no longer required.

3. Controlling the ignition of the main fuel. The controls set the FD dampers, ID dampers, cyclone shutoff dampers, and cyclone control dampers to obtain the proper amount of air flow for igniting the main fuel. Also, the primary/tertiary air shutoff damper is set to an intermediate position to limit the primary and tertiary air to the cyclone burner while the combustion air temperature is below 300 F.

When the proper air flow is set, the main fuel is introduced at an appropriate rate of feed for
establishing a main flame.

The "Combustion Controls" control the cyclone firing rate and provides proper fuel to air ratio in the cyclone throughout the load range. Maintaining the proper fuel to air ratio will ensure safe and efficient operation of the unit. The combustion control system is shown schematically in Figure 1. The description of the control requirements for this system has been separated into two sections, Fuel Flow Control and Air Flow Control.

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#BoilerManual #CycloneOperation #Section6 #Page2

time for the lighter flame. This control also shuts the lighter off when it is no longer required.

3. Controlling the ignition of the main fuel. The controls set the FD dampers, ID dampers, cyclone shutoff dampers, and cyclone control dampers to obtain the proper amount of air flow for igniting the main fuel. Also, the primary/tertiary air shutoff damper is set to an intermediate position to limit the primary and tertiary air to the cyclone burner while the combustion air temperature is below 300 F.

When the proper air flow is set, the main fuel is introduced at an appropriate rate of feed for
establishing a main flame.

The "Combustion Controls" control the cyclone firing rate and provides proper fuel to air ratio in the cyclone throughout the load range. Maintaining the proper fuel to air ratio will ensure safe and efficient operation of the unit. The combustion control system is shown schematically in Figure 1. The description of the control requirements for this system has been separated into two sections, Fuel Flow Control and Air Flow Control.

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#BoilerManual #CycloneOperation #Section6 #Page1

Cyclone operation

Controls for cyclone-fired boilers vary from comparatively simple to verify complex control systems. This is dependent on several factors such as the amount of automation desired, the safety features required, the type of boiler, the different fuels fired, the number of cyclone furnaces, the type of cyclone burner and fuel system, the type of air supply to the cyclones, and the degree of sophistication of fuel to air flow balancing control required.

In order to effectively discuss cyclone operation, we will be describing the various components associated with cyclone burners, the control parameters and the operating characteristics of the burner equipment.

OPERATION

There are two basic areas of control required for cyclone furnaces; burner operation and combustion control.

The Burner Operation functions include the following:

1. Control the air purge of the cyclones. Control of the cyclone shutoff dampers can be set to obtain 25-30% full load air flow through the cyclone for purge. Initial firing with uncured refractory in the cyclone requires that the controls be capable of purging at 25% full load air flow with the windbox to furnace delta-P at 10" H2O.

2. Controlling the ignition of the oil lighter. This is accomplished by controlling the FD dampers, ID dampers, cyclone shutoff dampers, and cyclone control dampers to regulate the air flow to an amount suitable for establishing lighter flame. A separate lighter control system introduces the ignition spark and lighter fuel at the proper

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#BoilerManual #CycloneOperation #Section6 #Page1

Cyclone operation

Controls for cyclone-fired boilers vary from comparatively simple to verify complex control systems. This is dependent on several factors such as the amount of automation desired, the safety features required, the type of boiler, the different fuels fired, the number of cyclone furnaces, the type of cyclone burner and fuel system, the type of air supply to the cyclones, and the degree of sophistication of fuel to air flow balancing control required.

In order to effectively discuss cyclone operation, we will be describing the various components associated with cyclone burners, the control parameters and the operating characteristics of the burner equipment.

OPERATION

There are two basic areas of control required for cyclone furnaces; burner operation and combustion control.

The Burner Operation functions include the following:

1. Control the air purge of the cyclones. Control of the cyclone shutoff dampers can be set to obtain 25-30% full load air flow through the cyclone for purge. Initial firing with uncured refractory in the cyclone requires that the controls be capable of purging at 25% full load air flow with the windbox to furnace delta-P at 10" H2O.

2. Controlling the ignition of the oil lighter. This is accomplished by controlling the FD dampers, ID dampers, cyclone shutoff dampers, and cyclone control dampers to regulate the air flow to an amount suitable for establishing lighter flame. A separate lighter control system introduces the ignition spark and lighter fuel at the proper

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