An Investigation of the Effects of Separating Pressure on the Efficiency and the Reliability of Three-Circuit Combined-Cycle Power Plants with Steam Reheating

摘要

The authors discuss the influence of selection of the separating pressure in designing three-circuit combined-cycle power plants (CCPP) with steam reheating on their technical and economical characteristics. The changes occurring in steam flow rates in the circuits, as well as in the efficiency of the waste heat recovery boiler (WHRB), the dryness factor, heat drops, the capacity and the efficiency of the steam turbine cylinders, the efficiency of the steam turbine and the CCPP as a whole, with the changes in the separating pressure, have been analyzed. It has been shown that the optimum separating pressure for the steam-power cycle with subcritical steam conditions ranges from 2.0 to 2.5 MPa.