| Popis: |
Aqueous mineral carbonation has been studied at the Albany Research Center as a potential option for CO2 sequestration. Studies have focused on the reaction of Ca-, Fe-, and Mg-silicate minerals with gaseous CO2 to form geologically stable, naturally occurring solid carbonate minerals. Process development has progressed in parallel with a process evaluation study, which was conducted for a mineral carbonation unit scaled to sequester 100% of the CO2 emissions from a 1.3 GW coal-fired power plant. The carbonation plant would require roughly 55 kt/day of mineral reactant to carbonate about 24 kt/day of CO2. The overall cost estimate was approximately $54(US)/ton CO2 sequestered. The power requirement determined for the mineral carbonation unit was about 352 MW, which represents 27% of the net power plant output. Improved mineral pretreatment and reactor design indicate that costs could be reduced by improvements to the reaction efficiency. However, because the material balance is dependent on the stoichiometry of the reaction, the chemistry of the silicate ore reactants, as well as the rection efficiency, the silicate ore demand cannot be reduced beyond a theoretical ratio of about 2:1, silicate ore to CO2. Based on these factors, mineral carbonation may be best suited as a nichemore » option for sequestration, where CO2 point sources coincide with sources of the desired mineral reactants, and may also favor an in situ methodology. Laboratory studies of in situ carbonation have shown promise.« less |
