Method for operating a gas turbine power plant with flue gas recirculation

摘要

A method is provided for operating a gas turbine power plant with flue gas recirculation, in which the flue gases are split into a first flue gas flow for recirculation into an intake flow of the gas turbine and into a second flue gas flow for discharging to the environment. The first flue gas flow is cooled in a recooler before its mixing with ambient air for forming the intake flow. The recirculation flow, after being recooled, is reheated in order to avoid condensation of vaporous water contained in the recycled flue gases during cooling as a result of the mixing with the ambient air. A gas turbine power plant is provided with flue gas recirculation, which includes a heat exchanger for reheating the recirculation flow after being recooled.

主权项

1. A method for operating a gas turbine power plant with flue gas recirculation, the gas turbine power plant including a gas turbine having a controller, a heat recovery steam generator and a flue gas splitter,
the method comprising:
splitting, by the flue gas splitter, flue gases of the gas turbine power plant into a first flue gas flow for recirculation into an intake flow of the gas turbine, and into a second flue gas flow for discharging to the environment;controlling, by a control element, the first flue gas flow;cooling, by a recooler, the first flue gas flow before mixing the first flue gas flow with ambient air for forming the intake flow; andafter the first flue gas flow is cooled in the recooler and before the first flue gas flow is mixed with the ambient air, reheating the first flue gas flow in a heat exchanger to avoid condensation of vaporous water contained in the first flue gas flow during cooling as a result of mixing with the ambient air, the heat exchanger being arranged in a recirculation line between the recooler and a location at which the mixing of the first flue gas flow with the intake flow occurs.