Boiler Components and Equipment

Boiler Auxiliaries

• Boiler auxiliaries include air preheaters, soot blowers, safety valves, fans, and boiler circulation pumps.
• These components are essential to the operation of the boiler and represent a significant portion of the overall steam-generator investment.

Air Preheaters

• Air preheaters are sized based on air and gas flows and temperatures, as well as allowable static pressure losses.
• Steam coil air preheaters require a manual for operation.
• Air preheaters can be water washed, but only when necessary, with the air preheater out of service, and after the boiler has been shut down and vacuumed clean.

Soot Blowers

• Soot blowers are selected based on the boiler configuration and probable dirtying characteristics of the oil ash.
• Soot blower systems include half retract and full retract soot blowers.

Fans

• Fans are used in the boiler auxiliary system, including forced draft air fans and gas recirculation fans.

Safety Valves

• Safety valves are used in the boiler system, including electromatic relief valves.

Boiler Circulation Pumps

• Boiler circulation pumps are used to circulate water within the boiler circuit.

Operation and Maintenance

• Station air must be supplied to the high-pressure nozzles for 5 minutes after soot blowing.
• High-pressure water washing should be conducted only when required to reduce the gas side pressure drop to within acceptable operating limits.
• Off-load high-pressure water washing should be conducted only when required.
• The air preheater should be inspected through the observation ports during and after washing.

References

• Multiple manuals and P&ID diagrams are referenced for specific equipment and systems.

Boiler Controls Training

• Warmkeeping System Line Valve Control prevents low pressure nuisance trips and zeros flow if no burner is in service.
• Remote demand comes in with delta setpoint to actual, restricted by the number of burners in service.

Controlled Equipment - Unit

• ID & FD FAN BLADE PITCH CONTROL is part of the CLC controlled equipment.
• FUEL CONTROL VALVES, BOILER FEEDWATER DEMAND, SH & RH SPRAYWATER CONTROL VALVES, STARTUP SYSTEM CONTROL VALVES, WINDBOX AIR DAMPERS, WINDBOX TILTS, GAS RECIRCULATION DAMPERS, and STEAM COIL CONTROL VALVES are also part of the CLC controlled equipment.

Fan Control

• Redundant pressure transmitters are used in fan control.

Combustion Air and Flue Gas Overview

• Combustion air and flue gas overview is a crucial part of boiler controls training.

Combustion Air and Flue Gas Train A

• Specific training is provided for combustion air and flue gas Train A.

Furnace Pressure Control Mimic (ID FAN CONTROL)

• Furnace pressure control mimic is used in ID FAN CONTROL.

Furnace Pressure / ID FAN CONTROL

• Furnace pressure control is crucial for ID FAN CONTROL.

NFPA 85 - Furnace Pressure Control Functional Requirements

• Block A shows the requirements for three furnace pressure transmitters arranged in an auctioneered median-select system, each on a separate pressure sensing tap, as per NFPA 85.

NFPA 85 Igniter Types

• Class 1 Igniter: Provides sufficient ignition energy (over 10% of full load burner input) to ignite fuel input under any burner light-off or operating conditions.
• Class 2 Igniter: Provides ignition energy (4-10% of full load burner fuel input) under prescribed light-off conditions and supports ignition under low load or adverse operating conditions.
• Class 3 Igniter: A small igniter that ignites fuel input to the burner under prescribed light-off conditions, with a capacity not exceeding 4% of the full load burner fuel input.
• Class 3 Special Igniter: A high energy electrical igniter capable of directly igniting the main burner fuel.

High Energy Arc (HEA) Retractable Ignitor

• Defined as a Class 3 Special Ignitor per NFPA 85.
• Capable of directly igniting the main burner fuel without a separate pilot ignitor.
• Standard GE practice for light-off of oil guns since the 1980s.
• Features an 8” stroke pneumatic cylinder, solenoid (retracts on loss of power), and advance and retract limit switches.

HEA Rod Assembly

• Comprises a guide tube and an HEA spark rod (Champion).
• The HEA spark rod is part of the HEA rod assembly.

HEA Insertion Target

• The HEA insertion target has an 8” stroke and inserts 7” into the spray.

Yanbu III Key Features

• Twin Fireball - Eight (8) Main WB Assemblies – Vertically Stacked Nozzles with +/- 30° Tilt Range.
• Future NG Elevation - Top End Air.
• 4 Spinner Vane Stabilized Oil Elevations / HEA & Flame Scanner.
• 3 NG Elevations / Twin Ignitor & Flame Scanner.
• Auto Tilt System +/- 30° CC-OFA thru UFA.
• CC-OFA +/- 20° Yaw.
• Top / BTM End Air.
• UFA Elevation.
• FGR Elevations +/- 30° Manual Tilt.

Corner Firing - Twin Fireball / One Burner - Control

• Features a corner firing arrangement.

Gas Firing System

• Yanbu firing system orientation is used for gas firing.
• Air flow control and distribution are crucial for proper air distribution.

Ignitor Assembly

• Components of the LimelightTM NG Pipe Ignitor include Spark Wiring, DFI Wiring Connection, Air Inlet, Dust Cap, Camlock Coupling, and ¼” NPT Gas Pressure Tap.

Gas Supply and Pressure

• NG Supply Pressure should be set to 2.8 psig for 12 BTU/hr.
• Air Pressure should be set to 3 in wc dp with lower furnace static pressure.
• NG Pressure can be adjusted via Valve Train Manual Globe Valve.
• Air Pressure can be adjusted via Butterfly Valve.

Scanner Cooling Air/Ignitor Air

• A pressure control damper is used to maintain a constant differential pressure between the Scanner Cooling/Ignitor Air Header and the Furnace.
• The ignition system may also be sized to provide sufficient heat input for warming of the unit.

NG Compartment – Pipe Ignitor

• NFPA Class 1 Ignitor is used to ignite the fuel input through the burner and to support ignition under any burner light-off or operating conditions.
• The ignitor provides sufficient ignition energy, typically in excess of 10% of full load burner input, at its associated burner to raise any credible combination of burner inputs of both fuel and air above the minimum ignition temperature.

NG Pipe Ignitor – 2 x 12 MBTU/Hr

• Class I Ignitor provides 10% Heat Input.
• NG Total Fuel Heat Input is 6,087 MBTU/Hr BMCR.
• Ignitor Firing Rate is 24 MBTU/Hr.
• Compartment Ignitor Proven Vote requires proving both ignitors in the compartment are in-service via IFM Flame Rod.
• Main Gas Operation requires 3 of 4 Compartment Ignitor Votes at Elevation - per Furnace Cell.