The formation permeability decreases in the process of oil wells operation. Ultrasonic treatment of the reservoir is an effective method of increasing the permeability without the risk of damage to nature. The method of acoustic treatment can be used as an additional method after applying the methods of physicochemical refining. At the same time, it should provide for increasing the effect of removal of solid particles and products of chemical treatment reactions from the treated zone by pressure drawdown. The experience of successful application of acoustic treatment at oil fields of Tatarstan and Western Siberia is analyzed. A magnetostrictive mechanical system, on which a variable voltage with a frequency of 10-20 kHz and a power of up to 5 kW was applied from the earth's surface via a geophysical cable, was used to create an ultrasonic field in the borehole. An algorithm for approximate evaluation of ultrasonic wave parameters in the reservoir is proposed. A formula for the wave damping coefficient is obtained. The effectiveness of acoustic treatment to increase permeability is shown experimentally by the method of neutron logging. It is established that the effect of the treatment begins to appear at a density of the emitted acoustic power of 20 kW/m2, the exposure time of 4–12 hours and the frequency of the acoustic generator selected within 10–20 kHz. It is established that the acoustic treatment has resonant behavior. An estimate of the effective zone radius for different wells under study is given.
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