METHOD FOR PROCESSING OF FORMATION FACE ZONE Russian patent published in 2004 - IPC

FIELD: oil and gas industry, in particular, methods for processing of formation face zone with reactants.

SUBSTANCE: method involves sequentially injecting alkaline buffer liquid, active reactant; holding to provide for reaction with formation rock and silt substances; withdrawing used reactant; removing reaction products from formation and bringing in a well. Injection of active reactant and withdrawal of used reactant are executed cyclically until natural formation face zone permeability is recovered. Active reactant is solution of the following composition, wt%: Trilon 0.35-28; alkaline metal hydroxide 0.05-7; water the balance. Upon withdrawal, used reactant is subjected to regeneration process. Volume ratio of alkaline buffer liquid to active reactant is: k=1.0-1.5. Method is preferably used on deposits, wherein well has been driven with the use of clay mortar heavy with barite-barium sulfate, as well as on deposits with abnormally high formation pressure and in super deep wells.

EFFECT: increased efficiency and provision for recovery of natural permeability of formation face zone.

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