PROCEDURE FOR TREATMENT OF BOTTOMHOLE ZONE OF WELL Russian patent published in 2011 - IPC E21B37/00 E21B33/10 

FIELD: oil and gas production.

SUBSTANCE: procedure consists in evacuation of fluid - water, condensate and mechanic impurities from bottomhole zone of well, in pumping reagents into oil-well tubing at closed annular space, in delivery of reagents to bottomhole of well with power of compressed air of annular space, in forcing reagents through into reservoir upon stabilisation of pressure in pipe and annular space, in evacuation of reaction products from reservoir, and in lowering and setting instrument - density metre - for record of changes of fluid density at bottomhole of well upon well shutdown. Reagents are driven into the reservoir and the bottomhole zone through orifices cut in a production string in gas medium in an interval of planned water-isolating operations, simultaneously there is supplied compressed nitrogen into annular and tube space and pressure of performed operation is controlled. The density metre is first arranged 10-15 m above lower orifices of the perforation interval, but upon pumping water-isolating reagents and upon forming a water-isolating screen a blocking solution is pumped and the density metre is positioned 100-150 m above a roof of the perforation interval to fix a level of the blocking solution. After process sedimentation calculated volume of killing fluid is refilled; its level is also measured with the density metre.

EFFECT: maintaining permeability of reservoir during repair operations.

6 dwg