METHOD OF EQUALIZATION OF INJECTIVITY PROFILE IN INJECTION WELLS AND RESTRICTION OF WATER INFLOWS TO PRODUCING WELLS Russian patent published in 2001 - IPC

FIELD: oil producing industry; applicable in development of oil pools at late stage. SUBSTANCE: method includes injection of isolating composition based on polymer, cross-linking agent and water into formation. Isolating composition is used in form of dispersion in water of carboxymethyl cellulose, polyacrylamide and cross-linking agent with the following amounts of components, wt.%: carboxymethyl cellulose 0.1-3.0; polyacrylamide 0.005-0.5; cross-linking agent 0.01-0.2; the balance water. Isolating composition, before gel formation is forced into formation to distance ensuring exclusion of influence of pressure differential on gel up to safe level. In high injectivity of well, isolating composition contains additionally filler in amount of 0.5- 10.0 wt.%. EFFECT: higher oil recovery from pool. 2 cl, 3 ex