Method for operating a once-through steam generator and once-through steam generator

摘要

The forced-flow steam generator (1) has one or more heating surfaces (2, 4) in its economizer (2) and vaporizer (4). A desired value of mass flowrate is made available to equipment adjusting the feedwater supply. At the same time a correction factor (K) is taken into account. This compensates for the rate of enthalpy- or density variation in the input flow to the heating surfaces. The correction factor is derived from the sum of derivatives with respect to time, of the density of the flow at both the inlets to and the outlets from the heating surfaces. An independent claim is included for a once-through or forced-flow steam generator.