Simulation of a NGCC power plant with CO2 capture: Exhaust gas pre-treatment strategies

BELZUNCE, PABLO S.; GARCÍA LAGOS, MARÍA V.; RODRÍGUEZ, MARÍA LAURA

Congreso; WCCE11 - 11th WORLD CONGRESS OF CHEMICAL ENGINEERING; 2023

The generation of electrical energy in Argentina depends heavily on thermal power plants, which in 2022 contributed 63% of the energy supply, 45% corresponds to natural gas combined cycle (NGCC). Post-combustion CO2 capture is promising in treating of exhaust gases due to its relative ease of integration into thermal power plants already built. Lithium orthosilicate (Li4SiO4) is considered a material of interest for this application CO2 reactive absorption is carried at 550 ºC and 10 bar. The CO2 separation process is significantly influenced by the CO2 concentration and the volumetric flow of the gas to be treated. This work aims to evaluate the energy efficiency of different exhaust gas pre-treatment configurations of a triple pressure NGCC power plant of 420 MW with CO2 capture. In the S1 strategy, the conditioning of the exhaust gases is carried out without modifying the original configuration of the standard plant. In the S2 strategy, the partial recycle of the flue gas stream towards the inlet of the gas turbine air compressor is proposed.The possibility of carrying out a recirculation of the exhaust gases has a favourable effect in increasing the absorption efficiency and in reducing the volume of the absorber.