Site screening for in situ mineral carbonation options in southern Portugal.

Abstract

The Sines industrial area is the largest CO2 emitting cluster in Portugal, with a coal power plant, a refinery and petrochemical facilities that can be responsible for almost a third of the national emissions from stationary sources. This cluster is seen as an early opportunity to deploy CO2 Capture and Storage (CCS) in Portugal, but the nearby offshore sedimentary formations do not provide economic conditions for storage of the CO2 [1]. If CCS is to be implemented, CO2 must be transported to other regions or alternative storage options need to be found. In-situ mineral carbonation in mafic and ultramafic rocks has been proved to be a valid alternative for permanent storage of CO2 at Carbfix (Iceland) and Wallula (USA) pilot injection sites. Furthermore, Carbfix demonstrated that CO2 dissolution in water during injection reduces the time scale for mineral carbonation to months and years, discards the need for extensive cap-rocks and allows for shallower injection depths, down to 200 m to 300 m [2]. These characteristics prompted project INCARBON to conduct a site screening process for mafic and ultramafic rocks in southern Portugal that can provide a mineral carbonation opportunity for the Sines cluster. Ongoing phases address the geological characterization and laboratory experiments.