Abstract
The Natural gas Combined Cycle (NGCC) with post combustion capture using liquid solvents may in some cases be of interest
to design with a flexible steam bottoming cycle, so that it can operate both with and without CO2 capture. It is then important
that the choice of the low pressure (LP) steam turbine exhaust size is made accordingly. The paper describes why a flexible
NGCC requires a LP steam turbine with smaller exhaust than the corresponding NGCC without CO2 capture, and how this will
affect the LP turbine exhaust loss and NGCC process efficiency. Handling large variations in LP steam flow is in fact wellknown technology in combined heat and power (CHP) plants, and the use of 3D simulation tools can further help making the
best LP steam turbine design choice.
to design with a flexible steam bottoming cycle, so that it can operate both with and without CO2 capture. It is then important
that the choice of the low pressure (LP) steam turbine exhaust size is made accordingly. The paper describes why a flexible
NGCC requires a LP steam turbine with smaller exhaust than the corresponding NGCC without CO2 capture, and how this will
affect the LP turbine exhaust loss and NGCC process efficiency. Handling large variations in LP steam flow is in fact wellknown technology in combined heat and power (CHP) plants, and the use of 3D simulation tools can further help making the
best LP steam turbine design choice.
