METHOD OF ISOLATION OF FORMATION HIGH-PERMEABILITY INTERVALS Russian patent published in 2002 - IPC

FIELD: oil producing industry; particularly, methods of isolation of formation high-permeability intervals in injection and producing wells. SUBSTANCE: method includes successive injection in fresh water buffers of fringes of polymer-silicated solution and aqueous solution of polyvalent metal salts. Fringe of polymer-silicate solution is injected in form of mixture of 0.05-0.1% solution of camcel with 5-10% solution of sodium silicated taken in ratio of 1:1. Fringe of aqueous solution of polyvalent metal salt is injected in form of aqueous solution of calcium chloride with density of 1.05-1.1 g/cu. cm. Fringes of solutions are injected in same volumes, 5-200 cu. cm each, until well injectivity drops by not in excess of 50%, with additional forcing of at least 40% of solution fringe volume. EFFECT: higher efficiency of isolation of high-permeability formation intervals due to increase of strength characteristics of grouting body, reduced its synergism in time, increased duration of isolation effect. 2 tbl, 2 ex