Dual Pressure Steam/Immiscible Liquid Cycles for Gas Turbine Exhaust Heat Recovery

Abstract

A dual pressure steam/immiscible liquid cycle gas turbine bottoming plant is described. Three variants of the cycle are analysed. It is shown that under typical conditions one of these shows a 5 percent higher output than the conventional steam/steam cycle with only a 5 percent increase in heat extraction from the gas turbine exhaust. A larger LP preheater and condenser are required. Attention is drawn to the flexibility this type of cycle brings to the task of matching bottoming plant to gas turbine exhaust of combined cycles.