METHOD FOR NEAR WELL-BORE TREATMENT WITH ACID Russian patent published in 2013 - IPC E21B43/27 

FIELD: oil and gas industry.

SUBSTANCE: method for near well-bore treatment with acid involves at the first stage pumping into the well of 10-15% aqueous solution of hydrogen chloride in a volume calculated on the basis of 0.25-0.5 m³ per 1 running metre of penetrated stratum depth; at the second stage - pumping of 10-15% aqueous solution of hydrogen chloride with a retarder of the acid reaction with rock in the volume of 2-5% of acid solution volume in total volume of pumping calculated on the basis of 1-1.5 m³ per 1 running metre of penetrated stratum depth at initial pressure equal to the final pressure value during pumping at the previous stage; overflushing by oil in volume of 5-15 m³ at initial pressure equal to the final pressure value during pumping at the previous stage; soaking during 16-48 hours and input of the well into operation.

EFFECT: improvement in efficiency of near-wellbore treatment.

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