Absorption of CO2 With Amines in a Semiclosed GT Cycle: Plant Performance and Operating Costs

Abstract

A CO2 removal system, using aqueous solutions of amines, is applied to a Semi-Closed Gas Turbine/Combined Cycle (SCGT/CC) power plant. The SCGT/CC is interesting because of the possibility of achieving low emissions at the stack, with a decreased overall flow rate, lower NOx concentration and an increased CO2 concentration (over 15% in volume), which facilitates the removal treatment. Several compositions of the absorbing solution have been investigated, by means of simulations with ASPEN PLUS. A 18% DEA + 12% MDEA composition resulted the most convenient in terms of flow rate and energy requirement for the stripping. A cost analysis of the removal plant allows to estimate additional costs for CO2 removal with respect to conventional power plants.