METHOD FOR BOTTOMHOLE PRODUCTIVE RESERVOIR ZONE TREATMENT Russian patent published in 2008 - IPC E21B43/18 

FIELD: oil industry, particularly enhanced recovery methods for obtaining hydrocarbons by repressuring or vacuum methods.

SUBSTANCE: method involves lowering pipe string in well; installing pipe string shoe provided with cavitational generator within productive reservoir range; injecting working agent; flushing bottom zone; injecting and forcing hydrocarbon solvent in reservoir. Pipe string shoe has integrated cavitational generator with working diffusers. Number of working diffusers is equal to 2 - 4 pairs. The working diffusers are transversal to well bore axis and are grouped in pairs tangentially directed to well bore wall so that 30-60° angle is defined in-between. Working agent is injected under depression in stalling cavitation regime along with cavitational generator reciprocation inside perforated reservoir thickness range.

EFFECT: increased well producing ability due to increased cavitational field power, cavitational field energy direction on productive reservoir along with production string protection against breaking cavitational field action on productive reservoir in depression state.

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