The preservation and longevity of power generation plant and stored machinery components is a significant problem, particularly in prolonged cold shut down situations.
Power station protection and component preservation using the desiccant dehumidifier method is not new and has been used since the mid 60’s in the power industry as a barrier to moisture related degradation.
Places in a power station where desiccant air dryers are recommended during shut down include:
Re-heater – tubes are thinner than superheater tubes and more susceptible to corrosion. Inter-granular attacks on austenic stainless steel can be minimised using dry air.
Generator – it is important to keep the windings dry to prevent corrosion and ensure a shorter restart time. Dry air can also supplement generator heaters.