A CCPP includes a gas turbine, a HRSG, a steam turbine a flash tank and first and second supply lines. The gas turbine, the HRSG and the steam turbine are interconnected to generate power. The gas turbine may include an air preheating system to preheat the air supplied in the gas turbine to enable expedite combustion therein. The flash tank is fluidically connected at a cold end of the HRSG to extract waste hot water from the cold end. Further, the first supply line is configured to interconnect the flash tank and the steam turbine to supply of flash steam to the steam turbine. Furthermore, the second supply line is configured to interconnect the flash tank and the air preheating system to supply hot flash condensate thereto.

A water/steam system for a combined cycle power plant and related method for operating said system are provided. The system comprises a heat recovery steam generator providing a flue gas stream path for extracting heat from a flue gas stream exhausted from a gas turbine, the heat recovery steam generator having a low pressure section including a low pressure evaporator arranged along the flue gas stream path for generating low pressure steam at a low pressure input level for a main input of a low pressure steam turbine. To use heat at low temperatures, the low pressure section may include a sub low pressure subsection with a sub low pressure evaporator for generating sub low pressure steam, at a sub low pressure level below the low pressure input level. The sub low pressure evaporator is disposed in the flue gas stream path downstream of a low pressure economizer.

Inlet air heating systems for combined cycle power plants and combined cycle power plants including inlet air heating systems are disclosed. The inlet air heating systems may include a plurality of heating coil assemblies partially positioned within an inlet housing of a gas turbine system, and a vent valve in fluid communication with each of the heating coils. The inlet air heating system may also include a supply line in fluid communication with the heating coils to provide water to the heating coils, and a hot water line in fluid communication with the supply line and a component positioned downstream of a condenser of the combined cycle power plant. The hot water line may provide hot water from the combined cycle power plant to the supply line. Additionally, the inlet air heating system may include a drain line in fluid communication with the heating coils and the condenser.

The present invention relates to a gas-steam combined cycle centralized heat supply device and a heat supply method. The gas-steam combined cycle centralized heat supply device comprises a gas-steam combined cycle system connected with a thermal station through a heating network return water heating system; the gas-steam combined cycle system comprises a gas turbine connected with a direct contact type flue gas condensation heat exchanger and a steam turbine via a waste heat boiler; the thermal station comprises a hot water type absorption heat pump and a water-water heat exchanger; the heating network return water heating system comprises a steam type absorption heat pump for recovering flue gas waste heat and a steam-water heat exchanger. The present invention can be widely applied to the industry of power plant waste heat recovery.

Integration of an oxyfuel combustion boiler at elevated pressures and a heat exchanger is achieved to produce carbon dioxide by feeding flue gas comprising carbon dioxide and water from the oxyfuel combustion boiler to a direct contact cooler column wherein water is condensed at a temperature of 0 to 10 C. lower than its dew point; feeding a portion of the condensed water from the direct contact cooler column to the oxyfuel combustion boiler; feeding a portion of the carbon dioxide from the direct contact cooler column to the oxyfuel combustion boiler; and recovering a portion of the carbon dioxide from the direct contact cooler column.

A power plant including a gas turbine, a waste heat steam generator and an intermediate circuit having a first heat exchanger, which is connected to an air inlet of the gas turbine, and a second heat exchanger, which is connected to a condensate circuit, having a condensate preheater in the waste heat steam generator. A first and a second high load valve, and parallel with these a first and a second low load valve for lower volume flows than through the first and second high load valve, are arranged on either side of the second heat exchanger. An associated method for optimizing efficiency and extending the operating range of a power plant.

The present invention provides a system for supplying heat by means of stratum coal in-place slurrying and a method for supplying power generation heat by means of stratum coal in-place slurrying, belonging to the technical field of ground-source well heat exchange. The system comprises a stratum coal slurrying device, a mid-deep well casing device and a heat exchange device. The stratum coal slurrying device comprises a water inlet pump and a coal slurry pump, which are connected to a directional slurry preparing drill through pipelines, respectively. The mid-deep well casing device comprises a vertically buried pipe, and a heat-insulating inner pipe that is coaxial with the vertically buried pipe and inserted into the vertically buried pipe. A microporous pipe assembly is arranged on the bottom of the heat-insulating inner pipe. An electric heater is arranged in the microporous pipe assembly, an annular cavity is formed between the vertically buried pipe and the heat-insulating inner pipe, and a power wire connected to the electric heater is arranged in the annular cavity. The coal slurry pump is connected to the annular cavity. The heat exchange device comprises a water outlet pipe that is inserted into the heat-insulating inner pipe and connected to the microporous pipe assembly. The present invention can directly combust the underground coal to generate heat energy to realize heat energy conversion, and the process is clean and harmless.

To provide a combined cycle plant, a control device thereof, and a steam turbine startup method that are aimed at improving the operability of a combined cycle plant by allowing a quick change of the output. A combined cycle plant is provided with: a gas turbine having a compressor, a combustor, and a turbine; a supplementary firing burner that raises the temperature of exhaust gas of the gas turbine; a heat recovery steam generator that generates steam using exhaust heat of the exhaust gas; a steam turbine that is driven by steam generated by the heat recovery steam generator; and a control device that changes both an output of the combustor and an output of the supplementary firing burner when an output of the combined cycle plant is to be changed.

Inlet air heating systems for combined cycle power plants and combined cycle power plants including inlet air heating systems are disclosed. The inlet air heating systems may include a plurality of heating coil assemblies partially positioned within an inlet housing of a gas turbine system, and a vent valve in fluid communication with each of the heating coils. The inlet air heating system may also include a supply line in fluid communication with the heating coils to provide water to the heating coils, and a hot water line in fluid communication with the supply line and a component positioned downstream of a condenser of the combined cycle power plant. The hot water line may provide hot water from the combined cycle power plant to the supply line. Additionally, the inlet air heating system may include a drain line in fluid communication with the heating coils and the condenser.

A power plant includes an exhaust duct that receives an exhaust gas from an outlet of the turbine outlet and an ejector having a primary inlet fluidly coupled to a compressor extraction port. The ejector receives a stream of compressed air from the compressor via the compressor extraction port. The power plant further includes a static mixer having a primary inlet fluidly coupled to a turbine extraction port, a secondary inlet fluidly coupled to an outlet of the ejector and an outlet that is in fluid communication with the exhaust duct. A stream of combustion gas flows from a hot gas path of the turbine and into the inlet of the static mixer via the turbine extraction port. The static mixer receives a stream of cooled compressed air from the ejector to cool the stream of combustion gas upstream from the exhaust duct. The cooled combustion gas mixes with the exhaust gas within the exhaust duct to provide a heated exhaust gas mixture to a heat exchanger.