LIGHT-WEIGHT OIL-WELL CEMENT MIX (VARIANTS) Russian patent published in 2005 - IPC

FIELD: building materials, particularly oil-well cements for cementing oil-, gas- and geothermal wells to prevent ingress of water and aqueous solutions into well.

SUBSTANCE: cement mix having 1.1-1.4 g/cm³ density consists of cement of widely used brand and light-weight filling agent added to cement in amount of 5.0-60.0% by weight. Light-weight filling agent is formed of composition including hollow aluminosilicate microspheres in amount of 80.0-95.0% by weight, kaolin in amount of 3.0-15.0% by weight and surface-active aluminum hydroxide in amount of 2.0-5.0% by weight. Hollow aluminosilicate microspheres are obtained by hydroseparation of aqueous ash slurry in ash disposal pond and have dimensions of 10-400 mcm and bulk weight of 0.3-0.5 g/cm³. One of well-known types of secondary or enriched kaolin containing Al₂O₃ in amount of 30.0-45.0 % by weight may be used as the kaolin for cement mix production. Surface-active aluminum hydroxide may be obtained by low-temperature carbonization of aluminate solutions and has specific surface of 300-500m²/g. Portland cements or other building cements are used for cement mix production. Cement mix having 1.1-1.4 g/cm³ density consists of cement of widely used brand and light-weight filling agent including hollow aluminosilicate microspheres with humidity of 30.0-65.0 % by weight added to cement in amount of 15.0-85.0% by weight. Portland cements or other building cements are used for cement mix production.

EFFECT: provision of necessary cement mix properties, easiness of cement mix availability, reduced cost.

10 cl, 2 tbl