During the startup of the triple-pressure HRSGs, plant staff noticed steam coming from the stack and a discrepancy between feedwater and steam flows. On shutting down the unit a T23 superheater tube was found with a complete circumferential failure. The failed tube was removed and the bore was plugged with some difficulty due to poor access and the uncommon material.
Waterside Deposits in evaporator tubes have been an issue in steam generators as long as boilers have been used. Substantial experience in deposit formation and management has been gained in conventional goal and oil/gas boilers over time. The role of boiling modes in the steam generator tubes is very critical to areas of deposit formation.