A comparative study of experimental and computed compressibility factors of methane-nitrogen-carbon dioxide system

Experimentally determined compressibility factors of a natural gas with impurities like carbon dioxide and nitrogen are found to differ with the values computed by various methods making use of compositional breakup of the gas. Compressibility factors for five mixtures of known composition were experimentally determined at room temperature, 100ºF, 125ºF, and 150ºF, and at pressure ranging between 1000 psi to 4000 psi. Using the known composition of the mixtures, compressibility factors were calculated by additive volume method and by Eilerts method. The deviation between computed and experimentally determined compressibility factors are at a maximum in the lower and higher pressure ranges --Abstract, page ii