Combined cycle power plant with auxiliary air-cooled condenser
AssigneeSiemens Westinghouse Power Corporation
InventorMichael Briesch
Life of this patent
Estimating the term…
Abstract
A combined cycle power plant (20) including a main air-cooled condenser (22) condensing steam at a first pressure and an auxiliary air-cooled condenser (24) condensing steam at a second pressure higher than the first pressure. Designing an air-cooled combined cycle power plant for startup on a hot day can significantly increase the size and cost of the required air-cooled condenser. Adding an auxiliary air-cooled condenser having appropriate thermal characteristics relative to a main air cooled compressor to the steam bypass circuit of an air-cooled combined cycle power plant enables the plant to meet plant startup requirements during periods of peak thermal load in a more cost effective manner than would be achievable with the main air cooled condenser alone.
Claims11
A condenser apparatus for a combined cycle power plant, said apparatus comprising:
- a main air-cooled condenser configured to condense steam at a first operating pressure;
- and
- an auxiliary air-cooled condenser coupled to the main air-cooled condenser, said auxiliary condenser configured to condense steam at a second operating pressure higher than said first operating pressure.
A combined cycle power plant comprising:
- a gas turbine;
- a heat-recovery steam generator receiving condensate and exhaust fluid from the gas turbine for producing steam;
- a steam turbine selectively receiving the steam from the heat-recovery steam generator;
- a main air-cooled condenser receiving the steam from the steam turbine and producing condensate;
- a condensate pump for returning the condensate to the heat-recovery steam generator;
- and
- a steam bypass circuit for selectively bypassing the steam around the steam turbine, the steam bypass circuit further comprising an auxiliary air-cooled condenser connected in parallel to the main air-cooled condenser and configured to operate at a pressure higher than an operating pressure of the main air-cooled condenser.
A method for performing a steam turbine startup comprising:
- operating a steam turbine bypass circuit comprising:
- a main air-cooled condenser configured to condense steam at a first operating pressure and an auxiliary air-cooled condenser coupled to the main air-cooled condenser, said auxiliary condenser configured to condense steam at a second operating pressure higher than said first operating pressure;
- selectively coupling said auxiliary condenser to the main air-cooled condenser using a valve;
- setting the valve in a closed condition, thereby allowing steam flow to bypass the auxiliary condenser and into the main condenser;
- and
- upon reaching a predefined steam turbine exhaust pressure, switching said valve to an open condition, thereby causing the auxiliary condenser to be in parallel circuit flow with the main condenser.
Dependencies are inferred from the claim text.