The El Segundo Combined Cycle Power Plant
Rob Swanekamp, PE, is director of the
HRSG User’s Group Conference and Ex-positon. Thamarai P. Chelvan is the engineering manager of Boiler and HRSG
Services for Siemens Energy Inc.
The Missing Link
BY ROB SWANEKAMP AND THAMARAI P. CHELVAN
WHEN STARTUP teams conduct overall-plant efficiency testing of new combined-cycle projects, they often overlook one of the necessary correction factors.
When they’re looking within the system boundary of the overall plant, the Startup
team typically does a thorough job—closely monitoring, and correcting for such
gas-turbine variables as firing temperature, ambient temperature, ambient humidity,
When they’re looking within the system boundary of the GT, however, some
Startup teams don’t do as thorough of a job. Specifically, they don’t always monitor,
and correct for tube fouling in the heat-recovery steam generator (HRSG), because
they assume that a brand-new HRSG isn’t going to have any significant fouling.
But experience in the HRSG User’s
Group—the combined-cycle industry’s
original and longest-running user group—
Our experience shows that even newly
erected HRSGs without a single operating
hour can have one to two inches, water
column, of tube fouling.
That’s what we’re calling “the missing
link” in combined-cycle efficiency calculations and we’re reminding Startup teams
of it in this article.
HOW CAN A BRAND NEW
HRSG HAVE THAT MUCH
Contamination starts depositing on
HRSG tubes “right from the get go,”
meaning it starts all the way back during
initial fabrication, because the original
equipment manufacturers (OEMs) aren’t