Abstract: In a method of operating a gas turbine and steam turbine installation with a gas turbine which can be operated with both gas and oil, a partial flow of heated feed water is injected into the cold condensate when a change is made from gas operation to oil operation. For this purpose, the installation comprises a mixing device, in which at least one spray head connected to a hot-water main, is arranged for the supply of the partial flow.

Abstract: In a method operating a gas and steam turbine installation having a gas turbine which can be operated with both gas and oil, during a change of operation from gas to oil, a partial-flow mixture formed from a first partial flow of heated feedwater and from a second partial flow of comparatively cool feedwater is admixed directly with the cold condensate. Thus, this is done without a heat exchanger. To this end, the installation includes a feed line for the heated feedwater. The feed line is directed to the condensate preheater and includes an admixing point for feeding the comparatively cool feedwater.

Abstract: In a method operating a gas- and steam-turbine plant (1) having a gas turbine (2) which can be operated with both gas and oil, during a change of operation from gas to oil, a partial-flow mixture (t1,2) formed from a first partial flow (t1) of heated feedwater (S′) and from a second partial flow (t2) of comparatively cool feedwater (S) is admixed directly with the cold condensate (K) and thus without a heat exchanger. To this end, the plant (1) comprises a feed line (104) for the heated feedwater (S′), this feed line (104) being directed to the condensate preheater (36) and having an admixing point (103) for feeding the comparatively cool feedwater (S).

Abstract: In a method of operating a gas turbine and steam turbine installation with a gas turbine which can be operated with both gas and oil, a partial flow of heated feed water is injected into the cold condensate when a change is made from gas operation to oil operation. For this purpose, the installation comprises a mixing device, in which at least one spray head connected to a hot-water main, is arranged for the supply of the partial flow.

Abstract: For achieving a high plant efficiency, a waste-heat steam generator, in particular for a combined-cycle power plant, has a number of heating surfaces heatable by a flue gas and carrying a medium to be heated. The steam generator can be operated at critical or supercritical pressures and has a once-through evaporator connected in countercurrent to the flue gas provided on a medium side. The evaporator is followed by a preheater and preceded by a superheater on a flue-gas side.

Abstract: A gas and steam turbine plant includes a coal gasification plant, a gas turbine connected downstream of the coal gasification plant, a steam turbine having a water-steam loop and a steam generator connected downstream of the gas turbine. The steam generator includes a preheater connected to the water-steam loop, a heater of a high-pressure stage connected downstream of the preheater, and a heater of a low-pressure stage connected upstream of the preheater. An outflow line leads into the coal gasification plant and is connected to the water-steam loop downstream of the preheater, as seen in water flow direction. A heat exchanger has a primary side integrated with the water-steam loop between the low-pressure stage and the high-pressure stage and a secondary side connected parallel to the outflow line.

Abstract: A gas and steam turbine plant includes a coal gasification plant, a gas turbine connected downstream of the coal gasification plant, a steam turbine having a water-steam loop and a steam generator connected downstream of the gas turbine. The steam generator includes a preheater connected to the water-steam loop, a heater of a high-pressure stage connected downstream of the preheater, and a heater of a low-pressure stage connected upstream of the preheater. An outflow line leads into the coal gasification plant and is connected to the water-steam loop downstream of the preheater, as seen in water flow direction. A heat exchanger has a primary side integrated with the water-steam loop between the low-pressure stage and the high-pressure stage and a secondary side connected parallel to the outflow line.