METHOD OF THERMAL ACID TREATMENT OF OIL AND GAS PLATES (OPTIONS) Russian patent published in 2018 - IPC E21B43/24 C09K8/592 

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to the field of oil production. Method of thermal acid treatment of oil and gas reservoirs having a temperature of 20–160 °C, in the first embodiment, is characterized by the fact that metallic magnesium or aluminum, or zinc in the form of rods with a diameter of 30–35 mm and a length of up to 1,000 mm or in the form of granules, are lowered into the response zone in a container on tubing, then ammonium nitrate is pumped in the form of a homogeneous 50–70 % aqueous solution, ammonium nitrate solution is pushed into the reservoir with water or oil, then 15–20 % hydrochloric acid is pumped in an amount of 110–120 parts per one part of magnesium or aluminum, or zinc, the ammonium nitrate solution is pumped into the reservoir to remove from each other at a distance of 4–15 m reaction zones – hydrogen formation zone by magnesium interaction or aluminum, or zinc with hydrochloric acid and the zone of reduction of ammonium nitrate to ammonium nitrite and the simultaneous decomposition of the resulting ammonium nitrite into nitrogen and water. Method according to the second variant is characterized in that an aqueous gel solution of ammonium nitrate with polyacrylamide is pumped into the well with the simultaneous introduction into it of the calculated amount of magnesium or aluminum powder, or zinc, and the ammonium nitrate solution is forced through with water or oil, then 15–20% hydrochloric acid in the amount of 110–120 parts per one part of magnesium or aluminum, or zinc is pumped; the ammonium nitrate solution is displaced into the reservoir to remove 4–15 m of the reaction zones from the other – the zone of formation hydrogen by the interaction of magnesium or aluminum, or zinc with hydrochloric acid and a zone of reduction of ammonium nitrate to ammonium nitrite and the simultaneous decomposition of the resulting ammonium nitrite into nitrogen and water.

EFFECT: improving the efficiency and safety of the method of thermo-acid treatment of the bottomhole zone, regulation of the acid neutralization rate.

2 cl, 2 ex