METHOD FOR RECOVERY OF LIQUID FROM UNDERGROUND RESERVOIR Russian patent published in 1997 - IPC

FIELD: oil and gas industry. SUBSTANCE: this can be used for recovery of hydrocarbon liquid from depleted oil reservoirs in oil and gas production industry. According to method, producing string is run down with lift of smaller diameter pipes and high-pressure chamber. This chamber is made of larder diameter pipes which are fastened on lift by means of adapter. Gas is injected into underground reservoir through inter-string space. Liquid is displaced from inter-string space and annular passage of high-pressure chamber. Gas is delivered from inter-spring space and reservoir to lift through high-pressure chamber. Liquid is recovered from gas lift. Upper part of high-pressure chamber is located above level of liquid in reservoir and is connected with reservoir. Gas is delivered from high-pressure chamber to lift through non-return valve. Created behind high-pressure chamber is column of liquid, and injection pressure and gas flow rate are maintained constant. EFFECT: high efficiency. 1 cl, 3 dwg