Comparative Life-Cycle Assessment of Slurry vs. Wet Carbonationof BOF Slag
Accelerated carbonation is a new C02 storage method under development as a solutionfor climatechangecausedbyanthropogenicactivities.Inacceleratedcarbonationanalkalinesourcesuch as minerals or industrial resid ues react with carbon dioxide in a presence of slightly acidicsolution to produce stable solid carbonates. There are varieties of accelerated carbonation routes,which differ in process condition. The aim of this study was to evaluate and compare the potential of a slurry route process and a wet route process for the carbonation of basicoxygenfurnace slag using the C02 emitted by a conventional natural gas power plant. For this pmpose alife cycle assessment (LCA) study was performed based on principles and guidelines provided byISO 14040:2006 and routines and data provided by the SimaPro V8 software package.Thematerial and energy requirements for each of the steps involved in the carbonation process, i.e.pre-treatment of raw material, C02 compression, transportation, carbonation step, after-treatmentand landfill, were calculated and included in the LCA study. The slurry and wet route resulted innet C02 reduction of 87.4% and 72.3% respectively. However, a positive contribution to otherenvironmental issues was observed with the wet route leading to higher impact mainly due tohigh heating requirement. An exception was the contribution of the slurry route to abioticresource depletion, which was higher for the slurry route due to high water requirement. Ageneral conclusion was that the electricity consumption is the main cause ofenvironmentalissues. Sensitivity analyses showed that the environmental impacts are dependent on thetransp01iation distance and electricity source, while no dependence was observed with respect toconstruction of the carbonation plant.
HÄR KAN DU HÄMTA UPPSATSEN I FULLTEXT. (följ länken till nästa sida)