# A Genetic Algorithm for optimization binary interaction coefficients for Methane

**Abstract **

In tins paper a Genetic algorithm as an advanced numerically method, has designed for a ternary system solution by Methane-Water-Ethylene glycol system solution, which System components based on absorption of natural gas process have reviewed. For this case, binary interaction parameters are very important at the cubic

Equations of state to the calculations of phase behavior at non ideal solution, and should be appointed for solutions. Here an equation of state for extending solutions at equilibrium of a multi-component system by using suitable mixing rules has defined. By applying the NRTL thermodynamic model for the Peng Robinson Equation of state, the water activity coefficients were calculated for the Methane-Water-Ethylene glycol ternary system. then Fugacity coefficient as a dependent parameter of activity coefficient and Gibbs energy appointed. Finally, water content as a function of fugacity, used for prediction of water associated in wet gas. a genetic algorithm for optimization binary interaction coefficients for Methane-Water-EG to appoint water activity coefficients and gas water content of gas has trained. This optimization can predict the parameters used for prediction of natural gas very well.