摘要：This work evaluated the phase transition from well bottom to well head and the physical parameters of high CO_2-bearing natural gas. The experimental results show that no phase change occurs in the process of reducing CO_2-containing natural gas from 45 MPa to 10 MPa. As the pressure increases, the gas deviation factor decreases first and then increases, the volume coefficient and the compression coefficient decrease, the density increases, and the amplitude of the density increase under high pressure is lower.When the pressure is the same, the relative volume, volume coefficient and compression coefficient of natural gas are basically unchanged with the increase of CO_2 content; the higher the CO_2 content, the smaller the deviation factor of natural gas and the higher the density. When the temperature rises, the relative volume and volume coefficient of natural gas increase, and the amplitude of increase under low pressure is more obvious than that under high pressure; the deviation factor increases, and the variation range is the largest at around 20 MPa; the density decreases, and the amplitude decreases under high pressure. The following is obvious; the effect of temperature on the compression factor is negligible.
