Calculation Method of Critical Flow Rate in Condensate Gas Wells Considering Real Interfacial Tension

Through study of gas-liquid interfacial tension of condensate gas reservoir and conventional gas well continuous-removal liquid model, this paper proposes a calculation method of critical flow rate in condensate gas wells with real interfacialtension to improve the accuracy of judgment of gas well liquid loading status used by conventional models. Analysis of thechanging characteristics of interfacial tension shows that condensate oil has low interfacial tension. When condensate gas wellliquid loading is analyzed, wells are suggested to be divided into two types: oil-gas wells and oil-water wells. Oil-gas interfacialtension was used in calculation for oil-gas wells, while gas-water interface tension was used in calculation for oil-water wells.According to the well production state, the actual temperature and pressure were used to calculate the interfacial tension.Three general models were modified by considering the variable interfacial tension, and the critical flow rates were calculatedfor 20 gas wells of a condensate gas field in Xinjiang. The results show that the accuracy rate of critical flow rate calculated bythe modified Turner's model reached 90%, which can be used as the judging standard of prediction of liquid loading in thisregion.