METHOD FOR REAGENT PROCESSING OF WELL Russian patent published in 2019 - IPC E21B43/22 E21B43/27 C09K8/40 C09K8/42 C09K8/74 C09K8/594 

FIELD: mining.

SUBSTANCE: invention relates to fuel and mining industry. Well reagent treatment method includes well killing by potassium-containing liquid containing, wt%: potassium carbonate K₂CO₃ – 5; water – balance. Volume of potassium-containing liquid is 2 m³ per 1 running meter of perforated thickness of formation. Then to the formation there pumped is an acidic process solution with pH 0.98–1.5, containing, wt%: NaHSO₄ sodium bisulphate – 3.0–8.0; potassium bromate KBrO₃ – 2.5–6.5; an anionic surfactant – 0.3; water for a process solution of acid action – balance, wherein water for process solution of acid action is saturated with protons in anode zone of electrolysis cell to oxidation-reduction potential equal to +650 mV before preparation of process solution of acid action. Volume of acidic process solution is 1 m³ per 1 running meter of perforated thickness of formation. Above acid action solution is maintained in formation for 1.5 hours. Then a buffer solution is injected into the formation, containing wt%: non-ionic surfactant – 0.1; water – balance. Volume of buffer solution is 2 m³ per 1 running meter of perforated thickness of formation. Immediately after injection of a buffer solution into the formation, a process solution of alkaline action with pH 8.85–9.5 is injected into the formation containing the following, wt%: sodium bicarbonate NaHCO₃ – 2.0–5.0; sodium hydroxide NaOH – 2.0–4.0; cation-active surfactant – 0.3; water for process solution of alkaline action – balance, wherein water for alkaline process solution is saturated with free electrons in cathode zone of electrolytic cell before oxidation-alkaline process solution preparation to oxidation-reduction potential equal to -550 mV. Alkali action process solution volume makes 1 m³ per 1 running meter of perforated thickness of formation. Said solution of alkaline action is maintained in formation for 1.5 hours. After that, well is developed with gaseous nitrogen.

EFFECT: increasing removal efficiency of colmatage formations at reagent treatment of well and well development as a whole.

7 cl, 19 tbl