A semiempirical approach for estimating the water content of natural gases

A semiempirical approach for estimating the equilibrium water content of natural gases in the liquid water-vapor and ice-vapor regions has been developed. This method estimates the water content of natural gases using water/ice vapor pressure and water/ice molar volume as well as pressure and temperature of the system. The approach has been developed using the experimental water content data for methane at a temperature range of 273.15 and 377.59 K and pressures up to 13.81 MPa. Experimental data for the water content of a hydrocarbon gas mixture (94% methane + 4% ethane + 2% n-butane) have been generated at a temperature range of 288.15 to 313.14 K and pressures up to 17.56 MPa using a static-analytic apparatus, taking advantage of a pneumatic capillary sampler for fluid sampling. These independent data have been used in examining the reliability of the semiempirical approach. The predictions of this approach are in good agreement with the experimental data generated in this work and those reported in the literature.