Sulfation rates of cycled CaO particles in the carbonator of a Ca‐looping cycle for postcombustion CO2 capture

Calcium looping is an energy-efficient CO2 capture technology that uses CaO as a regenerable sorbent. One of the advantages of Ca-looping compared with other postcombustion technologies is the possibility of operating with flue gases that have a high SO2 content. However, experimental information on sulfation reaction rates of cycled particles in the conditions typical of a carbonator reactor is scarce. This work aims to define a semiempirical sulfation reaction model at particle level suitable for such reaction conditions. The pore blocking mechanism typically observed during the sulfation reaction of fresh calcined limestones is not observed in the case of highly cycled sorbents (N > 20) and the low values of sulfation conversion characteristic of the sorbent in the Ca-looping system. The random pore model is able to predict reasonably well, the CaO conversion to CaSO4 taking into account the evolution of the pore structure during the calcination/carbonation cycles. The intrinsic reaction parameters derived for chemical and diffusion controlled regimes are in agreement with those found in the literature for sulfation in other systems. © 2011 American Institute of Chemical EngineersAIChE J, 2012

[1]  Borja Arias,et al.  An analysis of the effect of carbonation conditions on CaO deactivation curves , 2011 .

[2]  J. Carlos Abanades,et al.  CO2 Capture Capacity of CaO in Long Series of Carbonation/Calcination Cycles , 2006 .

[3]  Robert H. Borgwardt,et al.  Kinetics of the reaction of sulfur dioxide with calcined limestone , 1970 .

[4]  Mónica Alonso,et al.  Application of the random pore model to the carbonation cyclic reaction , 2009 .

[5]  Vasilije Manovic,et al.  SO2 Retention by CaO-Based Sorbent Spent in CO2 Looping Cycles , 2009 .

[6]  John R. Grace,et al.  Removal of CO{sub 2} by calcium-based sorbents in the presence of SO{sub 2} , 2007 .

[7]  Edward J. Anthony,et al.  Sulfation phenomena in fluidized bed combustion systems , 2001 .

[8]  Juan Carlos Abanades,et al.  Integration of a Ca looping system for CO2 capture in existing power plants , 2011 .

[9]  T. Shimizu,et al.  A twin fluid-bed reactor for removal of CO2 from combustion processes , 1999 .

[10]  D. D. Perlmutter,et al.  A random pore model for fluid‐solid reactions: I. Isothermal, kinetic control , 1980 .

[11]  John R. Grace,et al.  SO2 Removal and CO2 Capture by Limestone Resulting from Calcination/Sulfation/Carbonation Cycles , 2005 .

[12]  Paul S. Fennell,et al.  The calcium looping cycle for large-scale CO2 capture , 2010 .

[13]  D. D. Perlmutter,et al.  The effect of pore structure on fluid‐solid reactions: Application to the SO2‐lime reaction , 1981 .

[14]  A. Sánchez-Biezma,et al.  Oxyfuel carbonation/calcination cycle for low cost CO2 capture in existing power plants , 2008 .

[15]  E. Anthony.  Solid looping cycles: A new technology for coal conversion , 2008 .

[16]  K. Bruce,et al.  Effect of specific surface area on the reactivity of CaO with SO2 , 1986 .

[17]  P. Gayán,et al.  Comparison of mechanistic models for the sulfation reaction in a broad range of particle sizes of sorbents , 1996 .

[18]  R. H. Borgwardt.  Kinetics of the Reaction of SO2 with Calcined Limestone , 2006 .

[19]  Mónica Alonso,et al.  Modeling of the Deactivation of CaO in a Carbonate Loop at High Temperatures of Calcination , 2008 .

[20]  C. Müller,et al.  The Performance of a Novel Synthetic Ca-Based Solid Sorbent Suitable for the Removal of CO 2 and SO 2 from Flue Gases in a Fluidised Bed , 2009 .

[21]  R. Barker,et al.  The reversibility of the reaction CaCO3 ⇄ CaO+CO2 , 2007 .

[22]  Vasilije Manovic,et al.  Competition of sulphation and carbonation reactions during looping cycles for CO2 capture by CaO-based sorbents. , 2010, The journal of physical chemistry. A.

[23]  J. C. Abanades,et al.  Conversion Limits in the Reaction of CO2 with Lime , 2003 .

[24]  R. L. Pigford,et al.  Rate of Diffusion-Controlled Reaction Between a Gas and a Porous Solid Sphere - Reaction of SO2 with CaCO3 , 1973 .

[25]  John R. Grace,et al.  Simultaneous CO2/SO2 Capture Characteristics of Three Limestones in a Fluidized-Bed Reactor , 2006 .

[26]  V. Manović,et al.  Sequential SO2/CO2 capture enhanced by steam reactivation of a CaO-based sorbent , 2008 .

[27]  Robert W. Coughlin,et al.  Reaction of sulfur dioxide with limestone and the grain model , 1976 .

[28]  J. C. Abanades.  The maximum capture efficiency of CO2 using a carbonation/calcination cycle of CaO/CaCO3 , 2002 .

[29]  Matteo C. Romano,et al.  Coal-fired power plant with calcium oxide carbonation for postcombustion CO2 capture , 2009 .

[30]  J. S. Dennis,et al.  Mechanism of the sulphation of calcined limestone particles in combustion gases , 1990 .

[31]  J. Szekely,et al.  A changing grain size model for gas—solid reactions , 1979 .

[32]  Yongping Yang,et al.  Integration and evaluation of a power plant with a CaO-based CO2 capture system , 2010 .

[33]  J. Carlos Abanades,et al.  Determination of the Critical Product Layer Thickness in the Reaction of CaO with CO2 , 2005 .

[34]  K. Bruce,et al.  Investigation of product-layer diffusivity for CaO sulfation , 1987 .

[35]  Jochen Ströhle,et al.  Simulation of the Carbonate Looping Process for Post‐Combustion CO2 Capture from a Coal‐Fired Power Plant , 2009 .

[36]  M. Hartman,et al.  Reaction of Sulfur Dioxide with Limestone and the Influence of Pore Structure , 1974 .

[37]  E. J. Anthony,et al.  Fluidized bed combustion systems integrating CO2 capture with CaO. , 2005, Environmental science & technology.

[38]  G. P. Curran,et al.  Carbon dioxide-acceptor (coal) gasification process. Studies of acceptor properties. [Process discussed in light of required properties of CaO acceptor; limestones and dolomites are equally useful in process] , 1967 .

[39]  F. García-Labiano,et al.  Modelling for the high-temperature sulphation of calcium-based sorbents with cylindrical and plate-like pore geometries , 2000 .

[40]  Mónica Alonso,et al.  Sulfation of CaO Particles in a Carbonation/Calcination Loop to Capture CO2 , 2008 .