METHOD FOR TREATMENT OF WELL PERFORATED ZONE Russian patent published in 1995 - IPC

FIELD: mining industry. SUBSTANCE: method for treatment of well perforated zone includes injection into well of process solution, its holding in well, with subsequent removal of process solution and reaction products before arriving of formation fluid to well. Well perforated zone is treated in three stages: the first stage injection into well of process solution containing, mas. water 90.0-100.0; calcium dihydroorthophosphate 10.0-15.0; sulfur oxygen-containing compound 30.0-40.0; surfactant 0.15-0.25; the third stage injection into well of process solution containing, mas. water 90.0-100.0; sulfur oxygen-containing compound 30.0-40.0; surfactant 0.15-0.25. In so doing after injection of each process solution, additionally alternately injected and withdrawn is formation water in volume of 0.2-0.4 of pore volume of treated zone for 2-4 h. In this case, each process solution is held in well for 6-8 h. EFFECT: higher efficiency. 1 tbl