Combustion Air and Flue Gas System Training

521-01 Introduction to Combustion Air and Flue Gas Systems

When you complete this lesson, you will be able to describe how the overall combustion process works and demonstrate a working knowledge of the combustion air and flue gas systems.

  • Describe the indications of incomplete combustion
  • Define flash point
  • Describe primary and secondary air and the fans associated with them
  • Describe the following components of the flue gas system: Air preheater; Dust collector; Soot blower

521-02 Combustion Air and Flue Gas Flow Paths and Components

When you complete this lesson, you will be able to trace the flow paths of typical power plant combustion air and flue gas systems. You will also be able to describe the operation of major components within those flow paths.

  • Describe the individual flow paths of primary and secondary air
  • Compare the relative temperatures of the reheat and superheat boiler sections
  • Explain the use of forced and induced draft fans
  • Describe the function of the following flue gas system components:
    • Air preheaters
    • Scrubbers
    • Expansion joints

521-03 Control Loops and Methods of Control

When you complete this lesson, you will be able to discuss how control loops and methods of control can safely direct operational events in a power plant.

  • Demonstrate a fundamental understanding of logic diagrams
  • Discuss the importance of interlocks and describe how they work
  • Describe the operation of PID, closed loop methods of control

521-04 Combustion Air and Flue Gas System Start-up

When you complete this lesson, you will be able to describe the steps performed to put the boiler fan operation system into service.

  • Identify the importance of establishing air flow in the boiler with the induced draft (ID) fan
  • List verifications and tests to be completed prior to forced draft (FD) fan start-up
  • Describe the steps to start the FD fan
  • Describe preparations to ensure the ignitor air blowers are ready for service
  • List typical permissives to be satisfied before purging the boiler
  • Describe the steps to successfully purge the boiler
  • Describe the steps to put preheater into service

521-05 Maintaining Fan Operations in Combustion Air and Flue Gas Systems

When you complete this lesson, you will be able to describe how to perform the checks and monitoring necessary to maintain operation of fans and their components.

  • Identify the reasons for monitoring a fan’s current, bearing temperature, bearing vibration, and lubrication
  • List four checks you should perform as part of air preheater maintenance
  • Explain how leaks in the heat exchanger can affect fan performance
  • Describe operational maintenance procedures involving ignitor air fans, scanners, excess air, and the boiler
  • Discuss how to overcome the effects of abnormal conditions such as hunting, stalling, excess temperature, and vibration

521-06 Combustion Air and Flue Gas System Shutdown Process

When you complete this lesson, you will have an overall understanding of the shutdown process and general knowledge of an operator’s shutdown responsibilities.

  • Walk through the steps for boiler shutdown, describing procedures related to each of these critical components:
    • Primary Air (PA) Fan
    • Induced Draft (ID) Fan
    • Forced Draft (FD) Fan
    • Air preheaters
  • Explain how air flow and fuel flow are controlled during shutdown
  • Define thermal shock and explain how to avoid it during shutdown