METHOD OF OIL FORMATION STIMULATION Russian patent published in 2003 - IPC

FIELD: oil production; applicable in development of pools with high-viscosity oil, including bitumen oils for recovery of residual oil, selective waterproofing of formations, improvement of reservoir properties of oil-bearing formation, cleaning of bottomhole zones from mineral clusters and deposits of asphalt-resinous substances. SUBSTANCE: method includes running into one of wells, in zone of its perforation, of positive electrode-anode on tubing with connection of power immersed cable. Casing string of other well or string of group of other wells of same horizon serves as negative electrode-cathode. Wells of one group have hydrodynamic communication. Direct current with voltage of 150-450 V and current density of 0.1-100 A/sq. m is supplied to said electrodes. Current flow through formation multicomponent mixture results in its intensive heating. The higher is current density, the higher is temperature. Electrochemical, electrolytic, ion-plasma processes take place. Dissolved solid mineral clusters are withdrawn from formation to improve reservoir properties due to depression produced by pumps in all wells. Presence of high temperature results in change of oil viscosity to improve its fluidity and its displacement by agent. Relief temperature of formation is restored. Method provides for treatment of many wells economically efficiently without use of additional expensive chemical reagents, with observed ecological safety of oil recovery technology, considerable reduction of stimulation cost. EFFECT: higher efficiency of method. 1 ex