Gas Turbine Repowering Systems and Application

Abstract

Cogeneration systems (CGS) have been widely accepted in the market, and various modified systems are in operation. Among them, a gas turbine repowering system is very interesting, in which a gas turbine generator (GT) is added to an existing combined power system of a boiler and a steam turbine (ST). In this system, the exhaust heat of GT is directed to ST, is used as an additional combined cycle, and the overall heat efficiency is improved.
The characteristics of this repowering are : energy saving by 10-30 percent by step-by-step (cascade) energy use, less emission of carbon dioxide and nitrogen oxides, additional power generation by GT and total energy saving in a mill.