METHOD FOR TREATING DOWN-HOLE ZONE OF WELL IN MULTIPLE-BED OIL DEPOSIT Russian patent published in 1997 - IPC

FIELD: oil production industry. SUBSTANCE: this improves efficiency of treating down-hole zone due to selective action upon oil and flooded beds and isolation of flooded beds. Method implies muriatic treatment of interval after interval in each bed of multiple-bed deposit. Then oil emulsion is injected into oil beds. Flooded and oil beds are separated. Muriatic acid solution is injected into flooded bed. After that, acid-resistant plugging material is injected into flooded bed under pressure which is 10-20% higher than acid injection pressure. Then flooded bed and oil beds are connected. Cement bridge is created in well down to top of oil bed or to level which is 10 m higher than flooded bed. Then technological delay is effected, cement bridge is drilled out and oil beds are perforated. EFFECT: high efficiency.