Phase Behavior and Physical Parameters of Natural Gas Mixture withCO2

Abstract

The two-flash experiment, constant composition expansion experiment, saturation pressure measurement experiment, and phase transition observation experiment from well bottom hole to well head of four high CO2content natural gas samples were carried out by using the JEFRI-PVT apparatus made from DBR Company of Canada. The experimental results show that in the four high CO2content gas samples no phase transitions will take place at temperatures greater than 35°C. In the gas-liquid two-phase region, saturation pressures, critical pressure, critical temperature, and an integratedP-Tphase diagram of different CO2content natural gases are calculated by using the modified PR equation of state and modified (T) equation proposed by Saffari. The deviations between the saturation pressure calculated by using the model proposed in this study and experimental measured saturation pressure are very small; the average relative error is only 2.86%. Thus, the model can be used to predict the phase equilibrium parameters of high CO2content natural gas.

Identification and Quantification of CO2 Solidification in Cryogenic CO2 Capture from Natural Gas

“…Natural gas may have many impurities among which CO 2 is the major greenhouse gas. CO 2 content in natural gas may vary from 20% to 90% [3]. High CO 2 content in natural gas decreases its calorific value and also causes corrosion problems in the processing equipment.…”