(181e) Estimating the Compressibility Factor for CO2-Natural Gas Mixtures

There is a consensus among nations that CO2 emission to the atmosphere must be controlled via creating economically viable technologies for capturing, separation and long term storage of CO2 (CCSS). One of many possible proposed sequestrations is the injection of CO2 into depleted oil and gas fields.  However for planning such CO2 sequestration projects, accurate estimation of CO2-natural gas properties is required.

In this study a large data bank containing physical properties of various mixtures of CO2-natural gas properties at various temperatures and pressures has been collected. The data bank has been used to assess the accuracy of the industry standard methods in calculating the compressibility factor. The study indicated that these methods have series errors when they applied at high pressures, high temperatures, or at high content of CO2.

A new method is proposed in this study to calculate compressibility factor and density of CO2-natural gas mixtures.  It is capable of estimating the CO2- natural gas mixtures properties at various temperatures and pressures and for any level of CO2 content