Abstract: A process and system are disclosed for capturing carbon dioxide from a gas stream. The process and system comprises a first reactor in which a slurry of a metal silicate is reacted together with an ammonium salt in aqueous solution. The salt is one that does not form a precipitate with the metal silicate. In the first reactor the metal silicate reacts with the solution to produce a slurry of silica in an aqueous solution of a salt of the metal and ammonia. Ammonia gas is drawn off directly from the first reactor, and ammonia, including the ammonia drawn off from the first reactor, is added to the gas stream. The process and system also comprises scrubbing the gas stream, including with the added ammonia, with an aqueous solution, whereby the carbon dioxide and ammonia are absorbed into the solution and ammonium carbonate salt(s) are produced.

Abstract: A carbon dioxide sequestration process includes the following steps. In a first stage, a slurry of a metal silicate rock is mixed with ammonia so as to produce a ammonia/water/metal silicate slurry. In a second stage, the process includes scrubbing a gas stream containing carbon dioxide with the solution from the first stage to thereby absorb the carbon dioxide into a reactive slurry. In a third stage, the reactive slurry from the second stage is passed through a reactor that is controlled so as to promote the reaction between the carbon dioxide and the metal silicate to thereby produce a metal carbonate.

Abstract: A carbon dioxide sequestration process includes the following steps. In a first stage, a slurry of a metal silicate rock is mixed with ammonia so as to produce a ammonia/water/metal silicate slurry. In a second stage, the process includes scrubbing a gas stream containing carbon dioxide with the solution from the first stage to thereby absorb the carbon dioxide into a reactive slurry. In a third stage, the reactive slurry from the second stage is passed through a reactor that is controlled so as to promote the reaction between the carbon dioxide and the metal silicate to thereby produce a metal carbonate.