Case Study A: How can we help with your bottoming cycle issues.
CCGT plant with vacuum problems. Customer claims poor ST performance. ACC cleaning very disruptive for an uncertain return.
Scenario:
- 650 MW 2×1 CCGT power plant, 3-p level
- HRSGs and ACC as heat sink.
- Steep vacuum degradation over time.
- Drop in ST output.
- Risk of high-vacuum trips on hot days preventing GT to reach baseload.
- ACC cleaning may help but unsure how much. It’s also costly and disruptive for operations.
Recommended Services:
- Detailed Performance Assessment.
- Bottoming cycle focus.
Resolution
Audits & Testing
- Transmitter checks on ST and HRSG. (incl. water legs)
- WSC isolation audit.
- Air in-leakages assessment.
- ST steam seal system review.
- Max. load and 70% load data collection.
Analysis
- ST thermal characterization:
Swallowing capacities, P-ratio and section efficiency analysis. - HRSG characterization: flows & temperatures.
- ACC heat duty calculation.
- ACC performance validation.
- ACC techno-economic assessment.
Findings
+3%
ST OUTPUT
recoverable from excessive air-ingress & steam leaks detection.
+5%
GT OUTPUT
recoverable on hot days by eliminating risk of high vacuum
trips at baseload.
-10%
MAINTENANCE COST
from extended ACC cleaning periods through vacuum tracking.
How to Prevent: Degradation Tracker can help monitor ST performance and ACC condition.