PROCEDURE LEVELING PROFILE OF ACCEPTANCE OF INJECTION WELLS Russian patent published in 2001 - IPC

FIELD: exploitation of oil fields at latest stage with pumping of isolating compounds. SUBSTANCE: procedure includes determination of filtering properties of pool opened by injection well and isolation of interlayers with different absorption degree ( high, medium and low ) with subsequent isolation of them by pumping of isolating compounds. Isolation is started from interlayers with maximum absorption. Each interlayer is isolated by isolating compound penetrating this interlayer but not penetrating interlayer with less absorption. Compounds for isolation of interlayers with different absorption are selected by degree of their dispersity and viscosity. Viscoelastic gels and/or polymer-dispersive and fibrous compounds with particle size of 0.1- 1.0 mm is pumped for isolation of interlayers with high absorption-jointing supercollectors, isolating compound with particle size 0.005-1.0 mm is injected into pool with medium absorption and compounds forming high-dispersion sediment with particle size 0.01-0.4 μ after interaction in pool and/or gel-forming compositions with viscosity of 4.0-15.0 mPa•s is pumped for isolation of interlayers with low absorption. Isolating compounds are pumped practically without interruption. Stops between injections of isolating compounds into zones of different absorption can be made for period sufficient for gel formation, swelling of fibrous particles and/or settling of sediment in porous-jointing space of pool. EFFECT: provision for maximum coverage of pool by flooding thanks to prevention of advance of forcing agent over various most penetrable interlayers and man-made cracks. 1 cl, 1 tbl