... as an example):SystemMain equipmentBoiler properSteam drum, air heater, soot blower, refractory material, cyclone separator, air preheaterCoal feeding systemCoal silo, coal feeder, coal ... pipelineAir/gas systemPrimary air fan, secondary air fan, induced draft fan, high-pressure fluidized air fan, air fan motor, fan silencer, air/gas ductOil firing ...