SYSTEM FOR SEALING A SPACE IN A WELLBORE

摘要

A SYSTEM IS PROVIDED FOR SEALING A SPACE (7) IN A WELLBORE (1) FORMED IN AN EARTH FORMATION (2). THE SYSTEM COMPRISES A SWELLEABLE BODY (12) ARRANGED IN THE WELLBORE (1) IN A MANNER SO AS TO SEAL SAID SPACE UPON SWELLING OF THE SWELLEABLE BODY (12), THE SWELLEABLE BODY (12) BEING SUSCEPTIBLE OF BEING IN CONTACT WITH FORMATION WATER (4) FLOWING INTO THE WELLBORE (1), THE SWELLEABLE BODY (12) INCLUDING A MATRIX MATERIAL PROVIDED WITH A COMPOUND SOLUBLE IN SAID FORMATION WATER (4). THE MATRIX MATERIAL SUBSTANTIALLY PREVENTS OR RESTRICTS MIGRATION OF THE COMPOUND OUT OF THE SWELLEABLE BODY (12) AND ALLOWS MIGRATION OF SAID FORMATION WATER (4) INTO THE SWELLEABLE BODY (12) BY OSMOSIS SO AS TO INDUCE SWELLING OF THE SWELLEABLE BODY (12) UPON MIGRATION OF SAID FORMATION WATER (4) INTO THE SWELLEABLE BODY (12).