METHOD FOR HORIZONTAL WELL BOTTOM ZONE INTERVAL TREATMENT Russian patent published in 2008 - IPC E21B43/27 E21B43/18 

FIELD: oil production, particularly methods for stimulating production by forming crevices or fractures using eroding chemicals.

SUBSTANCE: method involves determining zones characterized by different oil saturation and permeability in horizontal uncased well bore; arranging flow string in cased vertical part of the well; locating extreme-line coiled tubing pipe inside flow string; arranging coiled tubing pipe end opposite to reservoir zone having minimal oil saturation and permeability; injecting acid solution in well through extreme-line coiled tubing pipe; lifting extreme-line coiled tubing pipe in cased well zone; forcing acid solution in reservoir through flow string; serially arranging extreme-line coiled tubing pipe end in reservoir zones characterized by increasing oil saturation and permeability; injecting acid solution in well through extreme-line coiled tubing pipe aligned with each zone; lifting extreme-line coiled tubing pipe in casing pie; forcing acid solution in reservoir through pipe string; performing time-delay and carrying out swabbing operation. Acid solution is forced at rate of 3-4 m³/hour under 1-3 MPa pressure at well head.

EFFECT: increased deliverability of well drilled in non-uniform reservoir.

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