METHOD FOR EXTRACTING NON-HOMOGENOUS MULTIBED OIL DEPOSIT Russian patent published in 2004 - IPC

FIELD: oil extractive industry.

SUBSTANCE: method includes pumping of working agent through force wells and extraction of oil through product wells from the beds. At least one well is stopped, previously perforated intervals are cemented, cement bridge is placed in the well with forming of new artificial pit-face above perforation intervals. At depth higher than upper interval of perforation a new slanting shaft of well is drilled with junction to horizontal shaft in non-extracted bed. New face is placed at distance of no less than 50m from face of previously drilled well. Drilled well is used as force well. Length of horizontal portion of well is selected on basis of needed well acceleration. Pressure and volume of pumping into drilled well is lessened for excluding outbreak of working agent into adjacent beds through behind-column space of main well shaft. Pumping of working agent is performed in cyclical mode. In product wells face pressure is heightened for value for which pressure of pumping working agent into force well was lessened.

EFFECT: higher oil yield due to better coverage of bed by operations, and use of previously idle productive beds.

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