Having looked at the steam and water circuits of boilers and HRSGs, we now move on to examine the plant which is involved in the combustion of fuel in boilers. The heat used for generating the steam is obtained by burning fuel in a furnace, or combustion chamber, but to do this requires the provision of air which is provided by a forced-draught (FD) fan (in larger boilers, two such fans are provided). After the fuel has been burned, the hot products of combustion are extracted from the furnace by another fan, the induced draught (ID) fan, and fed to the chimney. Again, two ID fans are provided on larger boilers. In this chapter we shall examine not only the burners or other equipment used to burn the fuel but also the fans and air heaters. Finally we shall briefly examine how gas turbines are used in combined-cycle plant.

Inspec keywords: furnaces; gas turbines; heating elements; fans; boilers; combustion; flue gases

Other keywords: furnace; steam circuits; air heaters; HRSG; burners; fuel combustion; hot products; fuel burning; boilers; combined-cycle plant; chimney; flue-gas circuits; induced-draught fan; combustion chamber; water circuits; forced-draught fan; gas turbines

Subjects: Gas-turbine power stations and plants