CROSS-LINKING BACKFILL MATERIAL FOR ISOLATION OF HIGH-INTENSITY ABSORPTION INTERVALS Russian patent published in 2024 - IPC C09K8/467 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, namely to backfill materials used for isolation of high-intensity absorption intervals. Cross-linking backfill material for isolating high-intensity absorption intervals includes caustic magnesite, magnesium chloride, a polysaccharide-based sedimentation stability regulator and water, wherein as a polysaccharide-based sedimentation stability regulator, the material contains guar gum, and additionally the material contains a thickening regulator based on oxalic acid, a gelation regulator – chromium acetate and a water-repellent additive in the form of an ethylene oxide solution in a non-polar solvent, with the following ratio of components, wt.pts.: caustic magnesite 100.0, thickening regulator 1.0-5.0, sedimentation stability regulator 0.25-0.6, water-repellent additive 3.18, gelling regulator 3.9-9.0, magnesium chloride 25.0-38.0, water 108.0-133.0, wherein magnesium chloride is contained in the form of an aqueous solution with density of 1.18-1.24 g/cm³, and the ratio of the amount of caustic magnesite in the material to the volume of the aqueous solution of magnesium chloride is 1:1.3-1.6. Additionally, the material contains a setting regulator – citric acid up to 2.0 wt.pts.

EFFECT: achievement of insulating properties, technologically necessary in conditions of high-intensity absorption with fracture opening from 10 mm, providing high structural and mechanical properties, low flowability and erosion of material in hollow space with simultaneous high thixotropy and ability to form indelible and impermeable cement screen, having high adhesion properties to the rock due to the combination of cross-linking properties of the polymer and the backfill material.

1 cl, 2 tbl