Application of accelerated carbonation treatment on alkaline residues

CAPPAI, GIOVANNA SALVATORICA;DE GIOANNIS, GIORGIA;DE GIUDICI, GIOVANNI BATTISTA;MUNTONI, ALDO;PIREDDA, MARTINA

2012-01-01

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Abstract

In this experimental study we evaluated the application of an accelerated carbonation treatment on alkaline residues, such as Air Pollution Control ash and Red Mud, to exploit their mineral alkalinity as permanent carbon storage via the mineral carbon sequestration process and at the same time improve their environmental stability. A direct aqueous accelerated process was applied to the two selected materials individually as well as to a mixture of the two residues (5% RM w/w). At the mild operating conditions adopted during the experiments, CO2 uptakes of 200 g/kg APC, 5.1 g/kg RM and 124.4 g/kg Mix APC+RM were obtained, that can represent a contribution to the reduction of their CO2 related plant emissions. Moreover, accelerated carbonation was able to neutralize Red Mud, decreasing its toxicity, and to reduce the mobility of Pb and Zn from APC, although it had a mobilization effect on Cd, Mo, Sb.