Gas and steam-turbine plant

A gas and steam-turbine plant, comprising:

• a gas turbine having blades;
• a steam turbine;
• a water/steam circuit connected to said steam turbine;
• a heat-recovery steam generator connected downstream of said gas turbine on a flue-gas side, said heat-recovery steam generator having heating surfaces connected in said water/steam circuit to said steam turbine;
• a steam collecting chamber having a number of sub-chambers connected to one another, said sub-chambers formed by a configuration of a number of bulkhead plates;
• a water/steam drum;
• a plurality of feed pipes disposed in parallel on a steam side connecting said water/steam drum to said steam collecting chamber, each of said sub-chambers of said steam collecting chamber connected to one of said feed pipes;
• and
• an evaporator disposed external to said heat-recovery steam generator and connected to said gas turbine for feeding cooled air to said blades of said gas turbine for cooling said blades, said evaporator having an inlet for receiving air as a heating medium and said evaporator cooling said air resulting in the cooled air, said evaporator having a secondary side connected to said water/steam circuit and open on an outlet side into said steam-collecting chamber.