A system for sealing a space in a wellbore comprising a swelleable body including a matrix material

摘要

A system is provided for sealing a space (7) in a wellbore (1), defined by a wellbore wall (8) and casing (6), formed in an earth formation (2) and capped by a wellhead (10) The system comprises a swelleable body (12) arranged in the wellbore in a manner so as to seal said space upon swelling of the swelleable body, the swelleable body being susceptible of being in contact with formation water flowing into the wellbore, the swelleable body including a matrix material provided with a compound soluble in said formation water. The matrix material substantially prevents or restricts migration of the compound out of the swelleable body and allows migration of said formation water into the swelleable body by osmosis so as to induce swelling of the swelleable body upon migration of said formation water into the swelleable body.