COMPOSITION FOR TERTIARY OIL PRODUCTION Russian patent published in 2002 - IPC

FIELD: oil and gas production. SUBSTANCE: invention proposes technology of tertiary displacement of oil involving reagents and their compositions, used to watering formations during production of oil from exhausted wells. Increase in oil recovery can be achieved when injecting composition lowering viscosity of oil to be displaced owing to presence in composition of low-molecular hydrocarbons, content of which being further increased by reaction of desulfurization of aromatic sulfonic acids and sulfonates in the course of tertiary oil production. Composition, in particular, contains, wt %: aromatic hydrocarbons 5-20, aromatic sulfonic acids and sulfonates 30-70, sulfuric acid or sodium, potassium, and ammonium sulfates 15-30, and water 5-35. Aromatic hydrocarbons can be represented by benzene, toluene, xylene, or their mixtures and aromatic sulfonic acids by benzene-, toluene-, and xylenesulfonic acids. EFFECT: increased oil recovery. 3 cl, 9 ex