CARBON DIOXIDE CHEMICAL SEQUESTRATION OF INDUSTRIAL EMISSIONS BY CARBONATION USING MAGNESIUM OR CALCIUM SILICATES

摘要

Processes, methods, system and uses in relation to chemical sequestration of carbon dioxide from a carbon dioxide containing gas by carbonation of an alkaline earth metal containing material. The carbon dioxide containing gas is contacted with an aqueous slurry in a carbonation unit for carbonation of at least a portion of the alkaline earth metal to produce a carbon dioxide depleted gas and a carbonate loaded slurry which is substantially exempt of precipitated alkaline earth. metal carbonates. The carbonate loaded slurry is then separated into an aqueous phase and a solid phase; and the aqueous phase is supplied to a precipitation unit for precipitating alkaline earth metal carbonates. The carbonation stage may be performed at a carbonation temperature between about 10° C. and about 40° C. and a carbonation pressure between about 1 bar and about 20 bars. The solid phase may be recycled to the carbonation stage.