Compositions and methods for well treatment

摘要

A self-healing cement for use in wells in which carbon dioxide is injected, stored or extracted, comprises a carbonaceous material. In the event of cement-matrix failure, or bonding failure between the cement/casing interface or the cement/borehole-wall interface, the material swells when contacted by carbon dioxide. The swelling seals voids in the cement matrix, or along the bonding interfaces, thereby restoring zonal isolation.