Abstract
In Kyoto, Japan on 11 December 1997, The Kyoto Protocol was adopted where leaders from various countries gathered to fight global warming by reducing greenhouse gas concentrations in the atmosphere to "a level that would prevent dangerous anthropogenic interference with the climate system". As they agreed to outline emissions targets such as CO2, various methods such as CO2 capture and storage were taken into considerations. Additionally, as a part of CCUS (Carbon Capture Utilization and Storage) technology, mineral carbonation technology (MCT) has caught attention in research as the “CO2 is chemically reacted with calcium- and/or magnesium-containing minerals to form stable carbonate materials which do not incur any long-term liability or monitoring commitments”.
MCT can be categorized into direct and indirect carbonation as illustrated in the Table 1. Direct carbonation was used for this study as it can be approached more easily in contrast to the indirect carbonation. In addition, in case of advanced electric power generation technologies such as the integration of coal gasification with combined cycles (IGCC) or with molten carbonate fuel cells (IGMCFC), direct gas-solid reaction reflects more efficiency of CO2 capture maintaining power generation. However, the disadvantage it holds is low carbonation rate and recycling the material.
MSW (Municipal Solid Waste) was utilized for mineral carbonation in this study. MSW thermal treatments generate fly ash and bottom ash. The latter is landfilled in South Korea after intermediate processing such as Solidification/Stabilization as it meets the allowable standard value of heavy metals although it has recyclable components. Also, the ash spawned could be exploited as an additive in cement or building materials. Therefore, we aim to perform mineral carbonation using MSW ash.
A comparative analysis of the efficiency of carbonation in context to the combustion method employing fluidized bed reactor and a fixed bed reactor was carried out. Furthermore, different experimental parameters were also examined to determine optimal experimental conditions for achieving maximum efficacy.
