Investigation on the reducing parameters of the Helmholtz energy equation of state for methane/methanol binary with VLE data

Natural gas is widely regarded as an efficient, relatively clean, and economically viable energy source. Its safe operation and continuous supply through pipeline infrastructure has led to its prominence in the energy sector. Methanol plays an important role in the natural gas industry, typically serving as a solvent or hydrate inhibitor. Therefore, the accurate estimation of thermodynamic properties for methane/methanol binary is extremely important to optimise the operating parameter, maximise the dehydration effect, and reduce the cost. As the Helmholtz energy equation of state is expected to offer high accuracy in predicting the vapour−liquid equilibrium of methane/methanol binary, four reducing parameters were derived based on collected experimental data. Additionally, the sensitivities of various reducing parameter combinations were simultaneously investigated. The results demonstrated a strong agreement between predicted fractions and experimental data, with the UMADs (uncertainty-weighted mean absolute deviation) of 3.484 and 0.665 for liquid and vapour phases, respectively. Meanwhile, it is deemed “very likely”, “likely”, and “unlikely” to achieve acceptable prediction for 3-parameter optimisation, 2-parameter optimisation and, 1-parameter optimisation, respectively.