METHOD OF GROUTING MORTAR-PREPARATION Russian patent published in 2003 - IPC

FIELD: methods of preparation of grouting mortars applicable in well cementing in oil and gas producing industry. SUBSTANCE: method includes dissolving in water of modifying reagent and superplasticizer S-3 based on sodium salt of product of condensation of naphthalenesulfonic acid and formaldehyde with subsequent mixing with oil-well Portland cement. Grouting mortar is prepared with 0.30-0.35 water-cement ratio. Modifying reagent is used in form of still bottoms of monoethanolamine - waste of cleaning of process gases with monoethanolamine in ammonia production. Still bottoms in amount of 0.1-0.3% of cement weight are dissolved in 90-92% of water of its total amount and mixed with oil-well Portland cement and subsequent mixing of forming suspension for 10-15 min, and superplasticizer 5-3 in amount of 0.7-1.5% of cement total weight is dissolved in remained water and mixed with suspension. EFFECT: higher quality of well lining due to use of grouting mortar with improved main mechanical and physical properties whose setting results in formation of strong cement stone with low permeability and higher adhesion to metal. 3 tbl, 12 ex