Review, modeling, Heat Integration, and improved schemes of Rectisol®-based processes for CO2 capture

The paper evaluates the thermodynamic performances and the energy integration of alternative schemes of a methanol absorption based acid gas removal process designed for CO2 Capture and Storage. More precisely, this work focuses the attention on the Rectisol (R) process specifically designed for the selective removal of H2S and CO2 from syngas produced by coal gasification. The study addresses the following issues: (i) perform a review of the Rectisol (R) schemes proposed by engineers and researchers with the purpose of determining the best one for CO2 capture and storage; (ii) calibrate the PC-SAFT equation of state for CH3OH-CO2-H2S-H-2-CO mixtures at conditions relevant to the Rectisol (R) process; (iii) evaluate the thermodynamic performances and optimize the energy integration of a "Reference" scheme derived from those available in the literature; (iv) identify and assess alternative Rectisol (R) schemes with optimized performance for CO2 Capture and Storage and Heat Integration with utilities. On the basis of the analysis of the Composite Curves of the integrated process, we propose some possible improvements at the level of the process configuration, like the introduction of mechanical vapor recompression and the development of a two stage regeneration arrangement. (C) 2014 Elsevier Ltd. All rights reserved.