Abstract: A combined cycle power plant and method for operating a combined power plant with stack energy control are presented. The combined cycle power plant includes a gas turbine, a heat recovery steam generator including a plurality of heating surfaces, and a steam turbine. The heating surfaces may be partially bypassed to reduce steam production in the heat recovery steam generator during power plant startup. Less energy may be extracted from exhaust gas of the gas turbine. More energy may be dumped through an exhaust stack. The steam turbine may start without restriction of a gas turbine load during power plant startup. The steam turbine may start without increasing a size of an air cooled condenser while maintaining a higher load of a gas turbine during power plant startup.

Abstract: A combined cycle power plant and method for operating a combined power plant with stack energy control are presented. The combined cycle power plant includes a gas turbine, a heat recovery steam generator including a plurality of heating surfaces, and a steam turbine. The heating surfaces may be partially bypassed to reduce steam production in the heat recovery steam generator during power plant startup. Less energy may be extracted from exhaust gas of the gas turbine. More energy may be dumped through an exhaust stack. The steam turbine may start without restriction of a gas turbine load during power plant startup. The steam turbine may start without increasing a size of an air cooled condenser while maintaining a higher load of a gas turbine during power plant startup.

Abstract: A system and method of treating an exhaust flow including nitrogen oxides (NOx) in a turbine engine power generation plant is provided. The turbine engine has a selective catalytic reduction system having a catalyst. During steady state operation of the engine, a reducing agent, such as ammonia, is supplied to an injector in an amount based on a measured molar flow of NOx in the exhaust flow. During a disturbance in the operation of the turbine engine, a reducing agent is supplied to the injector in an amount based on a predicted molar flow of NOx in the exhaust flow. In addition, the system can include a biasing feature in which additional reducing agent is supplied to the exhaust flow beyond the predicted molar flow of NOx. The system and method can mitigate NOx during transient engine operation, an operational mode in which emissions are difficult to predict and control.

Abstract: A system and method of treating an exhaust flow including nitrogen oxides (NOx) in a turbine engine power generation plant is provided. The turbine engine has a selective catalytic reduction system having a catalyst. During steady state operation of the engine, a reducing agent, such as ammonia, is supplied to an injector in an amount based on a measured molar flow of NOx in the exhaust flow. During a disturbance in the operation of the turbine engine, a reducing agent is supplied to the injector in an amount based on a predicted molar flow of NOx in the exhaust flow. In addition, the system can include a biasing feature in which additional reducing agent is supplied to the exhaust flow beyond the predicted molar flow of NOx. The system and method can mitigate NOx during transient engine operation, an operational mode in which emissions are difficult to predict and control.