Compositions and Methods for Well Completions

摘要

A self-healing cement for use in wells in which acid gases are injected, stored or extracted, comprises an acid-swelling 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 acid gases, including carbon dioxide and hydrogen sulfide. The swelling seals voids in the cement matrix, or along the bonding interfaces, thereby restoring zonal isolation. The acid swelling material may also be used without cement for remedial treatments to restore zonal isolation.

主权项

1. A composition, comprising water, a cement and a material that swells when contacted by a fluid with a pH lower than about 6, wherein the material comprises an amine polyacrylate copolymer.