Patent ID: 8468828

Claim:
A method for operating a steam cycle process which is performed in an apparatus comprising a steam generator, an expander, a condenser and a reservoir for the operating fluid, with the method comprising the following method steps: during the cold start of the steam cycle process, an operating fluid is supplied to the steam generator which comprises a working medium and an ionic fluid, with the ionic fluid being used as an anti-freeze and has a melting point beneath the freezing point of the working medium in the reservoir, with the decomposition temperature of the ionic medium lying above the evaporation temperature of the working medium in the steam generator; in the steam generator, the working medium is evaporated and is supplied in vapor form for relaxation to the expander by performing mechanical work and is subsequently condensed in the condenser; a separation of the ionic fluid and the working medium occurs upon reaching a predetermined operating temperature, so that the percentage by weight of ionic fluid in the operating fluid which is supplied to the steam generator decreases by at least 50%.