METHOD FOR STIMULATING BOTTOMHOLE FORMATION ZONE OF INJECTION WELL Russian patent published in 2016 - IPC E21B43/20 E21B37/06 

FIELD: oil industry.

SUBSTANCE: invention relates to oil production, and in particular to methods and devices for stimulation of formation and bottomhole zone in order to increase injectivity of injection wells. Method comprises conducting geophysical and hydrodynamic studies. According to results thereof, determining current state of bottomhole formation zone of injection well. Current state of bottomhole formation zone is considered unsatisfactory if a certain current value pickup is less than allowable limit value pick-up for an injection well. Flushing bottomhole formation zone with a volume of surfactant, providing rim, washed collector, subsequent injection. Volume of surfactant is determined based on geological formation parameters, including volume of treated area and porosity factor of formation. Providing dosing of surfactant for a predetermined time based on geologic formation parameters, including filtration and capacitive parameters of process variable and average daily volume of water injection into well. Daily dose volume of surfactant does not exceed 1 % of daily volume of water injection. Repeating geophysical and hydrodynamic studies. According to results thereof, determining current state of bottomhole formation zone of injection well. If re-determined current value pickup is greater than maximum limit value pickup for injection well, current state of bottomhole formation zone is considered satisfactory. If re-determined current value pickup is less than allowable limit value pick-up for an injection well, then make adjustments of surfactant dose and repeat step dosing surfactant. Adjusting dose of surfactant includes step of performing an adjustment of daily dosage amount of a surfactant, and adjustment of time of feed. Time for feeding next dose of surfactant is adjusted based on current radius of bottomhole formation zone, which is under influence of surfactant at a certain distance from bottom of injection well based on an analytical expression.

EFFECT: technical result is increasing injectivity of injection wells due to possibility of using fresh water in clastic reservoirs and ensure a uniform oil displacement.

10 cl, 2 dwg