BACKFILLING CEMENT GROUT OF SELECTIVE ACTION Russian patent published in 2009 - IPC C09K8/487 

FIELD: oil and gas production.

SUBSTANCE: invention refers to methods of sealing of annular and tube space and to elimination of inter-bed overflows in wells with closely located water-oil contact and can be used at repair-insulating works at oil production. Backfilling solution of producing wells contains, weight shares: Portland cement - 100, organic solvent compatible with water and oil - 32-40, oil soluble surface active substance SAS - 0.5-1.0, water soluble SAS - 0.5-1.0, fluid loss reducer of CFL type - 0.5-1.0, adhesion additive Concrepol - 1.0. Solution contains butyle-cello-solv or isopropyl alcohol or methyl alcohol, or glycol as the said solvent.

EFFECT: ability to complete replacement of liquid phase of backfilling solution with bed fluid at interaction, also high selectiveness of backfilling solution effect at high strength, and increased stability and sedimentation resistance, adhesion to metal and reduced viscosity.

2 cl, 2 tbl, 13 ex