A systematic approach for high temperature looping cycles integration

Abstract

High temperature solid cycles are promising technologies for implementing large-scale CO2 capture facilities in the mid-term. Energy integration plays a major role in the development of these cycles. Waste energy from the capture process may be used to retrofit an existing power plant or to power a new steam cycle, thus diminishing the energy penalty that the process entails. A procedure based on pinch analysis for the integration of these systems, is proposed and tested using limestone as CO2 sorbent. Although Li4SiO4 has been already dismissed for this purpose, it is used to validate the systematic procedure under a very different problem in terms of available heat and initial temperatures of hot streams. In both scenarios the integration was designed to take advantage of all available heat of the process and to power a supercritical steam cycle, quantifying their minimum energy penalty. A sensitivity analysis for each process was also developed, and the heat exchanger network achieved by the proposed algorithm obtained the best results in costs terms.