Predicting Phase Equilibria of Associating Fluids Using Cubic Plus Association Equation of State (CPA-EOS)
Personnel
| Chevron | TU PI's | Students |
|---|---|---|
| Jianxin Wang | Nagu Daraboina | Hanxiao Zhang |
Abstract
Peng-Robinson EOS is superior in predicting liquid densities especially for nonpolar materials and Soave-Redlich Kwong EOS is suitable for light hydrocarbons (C1-C10) and simple water handling. However, these cubic EOSs fail to predict phase equilibrium accurately for systems containing compounds capable of hydrogen bonding such as water, amines and alcohols. There are several cases in petroleum industry where phase equilibria of associating compounds is important. For example, calculation of the amount of hydrate inhibitors (methanol or ethylene glycol) to mitigate the risk of hydrate formation in offshore transport pipelines. It is important to predict the phase equilibria of these compounds accurately to design appropriate remediation strategies. Cubic plus association Equation of state (CPA-EOS) showed the promising advancement towards predicting these equilibrium conditions for associating fluids. CPA EOS is combination of simple cubic EOS, widely used in petroleum industry and association term in Statistical Associating Fluid Theory (SAFT) describing hydrogen bonding in a theoretically sound manner. The CPA EOS reduces to cubic EOS in the absence of hydrogen bonding compounds. The Overall goal of this project is to develop model to predict the thermodynamic experimental data of hydrocarbons and water systems using CPA- EOS.