Modelling and energy optimization of a natural gas combined cycle plant with post-combustion calcium looping CO2 capture

Abstract

Consulta en la Biblioteca ETSI Industriales (Riunet)

[EN] Greenhouse gases are becoming a highly important issue among the European governments, which have to meet what was agreed in Kyoto in 1997. In order to be able to comply with these objectives, a wide variety of possibilities can be used to attempt the target, such as the use of renewable energy sources or energy saving policies. Nevertheless, there is still a considerably big amount of gas, oil and coal that can provide the population energy for a number of years. A solution to use the resources and mitigate the contaminant emissions is to use carbon capture and storage. This technology can remove around 90% of power plant emissions, while integrated correctly with it. After that, the carbon dioxide is transported and stored in a safe location, such as depleted oil reservoirs or saline aquifers. The aim of this work is to study one of the possibilities of carbon capture applied to a specific power plant. The plant chosen in this case is a Natural Gas Combined Cycle. The technology selected for the capture is Calcium Looping which has recently been chosen as one of the most promising CO2 capture technologies [1]. For this study, a model of both plants will be performed in Aspen Plus, as well as an integration of both plants, discussing several possibilities. The best case scenario possible according to energy penalty calculations is to put the capture plant just after the gas turbine, in order to have hot gases entering the carbonator, which gives more heat into the reaction. This has an impact in the energy penalty decreasing it slightly without changing other parameters. Putting a secondary steam cycle also increases the performance of the plant substantially. .