Mineral trapping of CO2 via oil shale ash aqueous carbonation: Controlling mechanism of process rate and development of continuous-flow reactor system

Abstract

Ash containing considerable amounts of free lime as the most active compo-nent requires stabilization to assure safe landfilling. Using CO2 from flue gases as a neutralizing agent, also the emission of CO2 is diminished. The most extensive effect could be achieved by treating ash-water suspensions with CO2-containing gas. As even minute amounts of extraneous substances present in water influence the extent and rate of lime solubility in water, the behavior of lime as the key component of ash in various conditions was studied and the mechanism of process deceleration was proposed. As the next step, a laboratory-scale continuous-flow reactor system for aqueous carbonation of oil shale ash and main considerations for industrial pilot-scale plant design were developed. © 2009 Estonian Academy Publishers.