New association schemes for tri-ethylene glycol

Transportation of natural gas extracted from subterranean reservoirs is subject to several risks introduced by the presence water. These can be mitigated through subsea dehydration, design which requires an accurate understanding thermodynamics these systems. Having previously investigated use mono-ethylene glycol as a dehydration agent, this research focusses on industry workhorse: tri-ethylene (TEG). The Cubic-Plus-Association (CPA) equation state has provided good description for systems equal complexity and in work literature 4C 6D association schemes, well four newly proposed schemes (4F, 5F, 6F 5C) are evaluated TEG. explained manuscript, represent different ways self-association Pure component parameters estimated fitting vapor pressure, liquid density, liquid-liquid equilibrium data, with statistical uncertainty analysis implemented determine confidence intervals parameters. Binary interaction similarly fitted binary vapor-liquid (VLE) data. Optimized testing their performance predicting ternary VLE Due strong influence certain experimental data sets, shown unsuitable applications work. need consistent quantifying both phases, specifically TEG – CH4 been highlighted. best overall was obtained using 4F scheme. Along improved various LLE systems, average absolute relative deviations generally between 2-20%, single parameter sensitivity shows optimality also not included parameterization. This indicative better fundamental characterization molecule. value parameters, where temperature-dependent correlation unnecessary optimum schemes.