Abstract: A gas and steam-turbine plant includes a waste-heat steam generator connected downstream of a gas turbine on the flue-gas side. The waste-heat steam generator has heating areas connected in a water/steam circuit of a steam turbine. A heat exchanger is provided for cooling a coolant of the gas turbine in order to ensure reliable cooling of the gas turbine even under varied operating conditions. The heat exchanger has a secondary side connected in a second water/steam circuit. The second water/steam circuit is connected to the water/steam circuit of the steam turbine in such a way that it can be shut off. A method is also provided for cooling a coolant of a gas turbine of a gas and steam-turbine plant.

Abstract: A gas and steam-turbine plant having a heat-recovery steam generator which is connected downstream of a gas turbine on a flue-gas side is described. The heat-recovery steam generator has heating surfaces connected in a water/steam circuit of a steam turbine. Cooled air for cooling the blades can be directed via an evaporator to the gas turbine. The evaporator is connected on a secondary side to the water/steam circuit and opens on an outlet side into a steam-collecting chamber. The steam-collecting chamber is connected to a water/steam drum via feed pipes connected in parallel on a steam side. The intention is to ensure that, during the transport of the water/steam mixture from the evaporator to the water/steam drum, a separation of the two-phase mixture is reliably prevented. Therefore, the steam-collecting chamber has a number of sub-chambers, which are connected to one another and in each case assigned to a feed pipe.