[en] The device is designed to remove the afterheat of a e.g. gas-cooled reactor if the steam turbine of the steam power plant including a water-steam separating vessel is shut down. For this purpose already existing components are used to a large extent. E.g. a heat exchanger, which may be cooled externally, is connected to the outlet for the condensed water of a start-up flash tank of the plant. It is also possible to use the heat exchanger as a preheater, whose connections for the turbine steam may selectively be connected to coolant pipes. (orig./PW)