chemical engineering research and design 8 9 ( 2 0 1 1 ) 1600–1608 Contents lists available at ScienceDirect Chemical Engineering Research and Design j ourna l ho me pa ge: www.elsevier.com/locate/cherd Modelling reactive absorption of CO 2 in packed columns for post-combustion carbon capture applications F.M. Khan 1 , V. Krishnamoorthi 2 , T. Mahmud ∗ Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, The University of Leeds, Leeds LS2 9JT, UK a b s t r a c t A rate-based process model for the reactive absorption of carbon dioxide (CO 2 ) from a gas mixture into an aqueous monoethanolamine (MEA) solution in a packed column is developed. The model is based on the fast second-order kinetics for the CO 2 –MEA reactions and takes into account the mass transfer resistances. The heat effects associated with the absorption and chemical reaction are included through energy balances in the gas and liquid phases. Appropriate correlations for the key thermodynamic and transport properties and for the gas–liquid mass transfer are incorporated into the model to ensure reliable predictions. The model predictions are validated by simulating a series of experiments conducted in pilot and industrial scale absorption columns with random and structured packings reported in the literature. Comparisons between the simulation results and the experimental data reveal good quality predictions of the gas phase CO 2 and MEA concentrations and the liquid temperature along the column height. The sensitivity studies reveal that the correlations for the gas- and liquid-film mass transfer coefficients given by Onda et al. (1968) provide better predictions than the penetration theory of Higbie (1935) and the correlation of Bravo et al. (1985). © 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Keywords: Carbon capture; CO 2 –MEA absorption; Reactive absorption; Process modelling 1. Introduction In recent years, there has been increasing demand for a sig- nificant reduction of carbon dioxide (CO 2 ) emissions from industrial sources to alleviate the global warming problem. Following the 1997 Kyoto Protocol, the European Union has set a target of 20% reduction of CO 2 emission by the year 2020. In order to meet this target, a significant reduction of CO 2 release from fossil fuel fired thermal power plants, which contribute approximately 25% to the total global emis- sions (WRI, 2007), will be required. This can be achieved by adopting an effective strategy for carbon capture and stor- age (CCS) such as the pre-combustion CO 2 capture technology as used in the integrated gasification and combined-cycle (IGCC) plants, oxyfuel combustion for the production of sequestration-ready CO 2 or the post-combustion CO 2 capture ∗ Corresponding author at: Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, The University of Leeds, Engineering (Houldsworth) Building, Leeds LS2 9JT, UK. E-mail address: T.Mahmud@leeds.ac.uk (T. Mahmud). Received 15 May 2010; Received in revised form 14 September 2010; Accepted 30 September 2010 1 BP Exploration, 1–4 Wellheads Avenue, Dyce, Aberdeen, AB21 7PB, UK. 2 Hindustan Unilever Research Centre, 64 Main Road, Whitefield, Bangalore-560066, India. from flue gases which would otherwise be vented to the atmo- sphere (Wilson and Gerard, 2007). The latter technology is being considered by the power generation industry as one of the potential options. In principle, CO 2 can be removed from a gas stream using several separation processes including physical/chemical absorption into a liquid solvent, adsorp- tion on solids, permeating through membranes, and chemical conversion. Reactive absorption using aqueous alkanolamine solutions, including monoethanolamine (MEA) solutions, in packed columns are widely used for the separation of CO 2 from process gas streams in the chemical and petroleum industries. This is a well-developed technology and is currently the most preferred process approach for the CO 2 capture from power plant flue gases (Freund, 2003; Idem and Tontiwachwuthikul, 2006). However, packed-bed absorption columns are known to suffer from various operational problems including high gas 0263-8762/$ – see front matter © 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.cherd.2010.09.020