A Study on Maximizing Power Output of IGCC Plants Considering Operating Limitations of Gas Turbine

Abstract

This study aims to provide a systematic overview of the relations between IGCC performance and major design and operating parameters such as integration degree, nitrogen dilution, and ambient temperature. A unique feature of this study is that allowable maximum values of both the gas turbine power ouput and the turbine blade temperature were considered. For this purpose, a simulation tool to predict operation and performance of a syngas turbine, which was modified from a base gas turbine model, was set up using off-design models. Then, an entire integrated gasification combined cycle using the syngas turbine was modeled. The power block (i.e. the combined cycle) was modeled in detail and mass and energy interactions of the power block with a gasifier block and an air separation unit were included. Variation in syngas turbine power output according to varying nitrogen dilution was simulated and operating conditions where gas turbine power needs to be suppressed to the allowable maximum value were found out. Maximum net IGCC power output under the limitations of gyngas turbine power and blade temperature was predicted for various integration degrees in a wide ambient temperature range. The influence of steam dilution on plant performance was also investigated.