Isobaric heat capacities of liquefied natural gas (LNG) mixtures by differential scanning calorimetry at temperatures from 116 K to 150 K and pressures up to 6.90 MPa
Year: 2024
Type: article
Abstract: The isobaric heat capacity (cp) is a crucial thermodynamic property for LNG industries in process design and optimization. Reliable cp results can be applied to validate and improve the equation of state performance under relevant industry conditions. Here, we report the results of cp measurements performed for eight LNG mixtures between (116.3 to 150.3) K and pressures ranging to 6.90 MPa. The results achieved were compared against four thermodynamic models: the fundamental equation of state (EOS) for liquefied natural gas (EOS-LNG), the Peng-Robinson (PR) cubic EOS widely applied in process design, the Lee-Kesler-Plöcker (LKP) EOS, which is reliable for gas enthalpy computation, and the Statistical Associating Fluid Theory (SAFT)-γ Mie EOS integrating contributions from functional groups. The EOS-LNG, which is equivalent for the mixtures investigated in this work to the GERG-2008 Helmholtz equation of state, can satisfactorily compute all the measured heat capacities. The SAFT-γ Mie EOS exhibits excellent accuracy when the correct ideal gas heat capacity correlation is implemented. On the contrary, the PR and LKP EOS show systematic deviations as a function of density, which stem from poor residual heat capacity predictions for the pure constituents and binary mixtures.
Source: Fuel
Authors: Xiong Xiao, Markus Richter, Eric F. May
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,200
OpenAlex ID: W4402889774