Integration of a Ca looping system for CO 2 capture in existing power plants

This work analyses a Ca looping system that uses CaO as regenerable sorbent to capture CO 2 from the flue gases generated in power plants. The CO 2 is captured by CaO in a CFB carbonator while coal oxycombustion provides the energy required to regenerate the sorbent. Part of the energy introduced into the calciner can be transferred to a new supercritical steam cycle to generate additional power. Several case studies have been integrated with this steam cycle. Efficiency penalties, mainly associated with the energy consumption of the ASU, CO 2 compressor and auxiliaries, can be as low as 7.5% p. of net efficiency when working with low‐CaCO 3 make‐up flows and integrating the Ca looping with a cement plant that makes use of the spent sorbent. The penalties increase to 8.3% p. when this possibility is not available. Operation conditions aiming at minimum calciner size result in slightly higher‐efficiency penalties. © 2010 American Institute of Chemical Engineers AIChE J, 2011