METHOD OF BOTTOM-HOLE ZONE TREATMENT OF LOW-PERMEABLE TERRIGENOUS FORMATIONS (VERSIONS) Russian patent published in 2012 - IPC E21B43/27 E21B43/22 

FIELD: oil and gas production.

SUBSTANCE: method of bottom-hole zone treatment of low-permeable terrigenous formation according to the first version consists in flushing of killed well, sequential pumping of methanol, 18-20% solution of hydrochloric acid for acid bath installation, then the well is repeatedly pumped by 18-20% solution of hydrochloric acid and buffer-gas condensate, acid composition is squeezed into bottom-hole zone of formation by inert gas, then mud acid solution is pumped, gas influx from formation is caused and then reaction products are removed together with gas flow, the well is treated through flare line with removal of reaction products till it reaches design conditions and then the well is placed under production. Method of bottom-hole zone treatment of low-permeable terrigenous formation according to the second version consists in sequential pumping of methanol, 18-20% solution of hydrochloric acid and buffer-gas condensate into non-killed well through tubing casing, acid composition is squeezed into bottom-hole zone of formation by inert gas, then mud acid solution is pumped, gas influx from formation is caused and then reaction products are removed together with gas flow, the well is treated through flare line with removal of reaction products till it reaches design conditions and then the well is placed under production.

EFFECT: recovery of gas-hydro-dynamic connection of well with low-permeable and highly colmataged terrigenous productive formation in condition of abnormally low formation pressure.

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