Application of gas lift plugging removal technology in exploitation of weakly volatile oil and gas reservoirs

Abstract A certain block exhibits the characteristics of a weakly volatile oil and gas reservoir featuring strong oil volatility, substantial gas production and high pressure. Owing to insufficient formation energy and tubing blockage, retrograde condensate oil and formation water accumulate in the wellbore, significantly affecting the normal development and production of the oilfield. Aiming at the issue that the production layer is suppressed by the water column, through the research and application of the supporting technology of the membrane nitrogen gas lift unplugging process, the parameters like the pressure, flow rate, and time of the injected nitrogen were precisely calculated and simulated to attain the optimal unplugging effect. Through gas lift, the bottomhole pressure was decreased, the production pressure differential was increased, the wellbore temperature was prominently raised, and the viscosity of the wellbore crude oil was effectively reduced. The accumulated liquid was rapidly discharged, the formation energy was replenished timely, the secondary damage to the reservoir was minimized to the greatest extent, and the self-flowing ability of the formation was successfully restored, which strongly guaranteed the normal production of the oil well and ultimately achieved the goal of significantly enhancing the development effect of the oilfield.