Study of phase and physical property changes during gas lift injection of high CO ₂ ‐content associated gas in the offshore M oil field

The gas lift in the offshore M field will be performed with high CO2-content associated gas, but change of wellbore temperature and pressure during injection process lead to phase physical parameters which has a great impact on design lift. To ensure smooth implementation field, this paper conducts study considering CO2 state. We obtained density, viscosity, compression factor, constant specific heat capacity, thermal conductivity, Joule Thomson coefficient at each by Hysys calculation, regression analysis obtain model parameters; finally, was compared flash experiment calculation results. results show that large influence R2 > 0.8, indicates sufficient reliability; comparison empirical formulas all properties have accuracy superiority except Joule–Thomson coefficients. In addition, formula also good not exceeding 22 MPa. changes content provides basis for subsequent multiphase flow calculations Although is only applicable sample, it feasible research method other samples.