Effect of milling mechanism on the CO2 capture performance of limestone in the Calcium Looping process

This work analyzes the relevant influence of milling on the CO2 capture performance of CaO derived from natural limestone. Diverse types of milling mechanisms produce contrasting effects on the microstructure of the CaO formed after calcination of the milled limestone samples, which affects cruciall...

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Bibliographic Details
Authors: Benítez Guerrero, Mónica, Valverde Millán, José Manuel, Perejón Pazo, Antonio, Sánchez Jiménez, Pedro Enrique, Pérez Maqueda, Luis Allan
Format: article
Status:Versión aceptada para publicación
Publication Date:2018
Country:España
Institution:Universidad de Sevilla (US)
Repository:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/137873
Online Access:https://hdl.handle.net/11441/137873
https://doi.org/10.1016/j.cej.2018.03.146
Access Level:Open access
Keyword:Ball milling
Calcium-Looping
CO2 capture
Crystallite size
Porosity
Description
Summary:This work analyzes the relevant influence of milling on the CO2 capture performance of CaO derived from natural limestone. Diverse types of milling mechanisms produce contrasting effects on the microstructure of the CaO formed after calcination of the milled limestone samples, which affects crucially the kinetics of carbonation at conditions for CO2 capture. The capture capacity of CaO derived from limestone samples milled using either shear or impact based mills is impaired compared to as-received limestone. After calcination of the milled samples, the resulting CaO porosity is increased while crystallinity is enhanced, which hinders carbonation. Conversely, if the material is simultaneously subjected to intense impact and shear stresses, CaO porosity is promoted whereas CaO cristanillity is reduced, which enhances carbonation in both the reaction and solid-state diffusion controlled regimes.