Wide Range, High Accuracy PρT Measurements by Single Sinker Magnetic Suspension Densimeter for Natural Gas-Like Mixtures

Force Transmission Error Analysis for a High-Pressure Single-Sinker Magnetic Suspension Densimeter

“…The titanium sinker mass and volume were 30.39159 g and 6.741043 cm 3 , and the copper sinker mass and volume were 30.398939 g and 3.403268 cm 3 (determined using the apparatus and procedure described by McLinden and Splett [9]). Patil et al [3,4] described the single-sinker MSD, and additional modifications to expand the range of measured temperature appeared in [5,6]. The Platinum resistance thermometer (PRT) (Minco Products Model S1059PA5X6) has been calibrated at fixed temperature points defined by ITS-90 and by a calibrated PRT traceable to NIST.…”

“…Knowledge of the apparent weight of the sinker and its properties allows determination of accurate densities for the fluid. The general features of this apparatus appear in [1] and [2], and the specific details of the present instrument appear in [3][4][5][6].…”

“…Rubotherm Präzisionsmesstechnik GmbH manufactured our single-sinker MSD designed to work at pressures up to 200 MPa over a temperature range of 193 K to 523 K. We have used this apparatus to measure densities of mixtures similar to natural gas as well as for low-and high-pressure densities for pure components [3][4][5][6]. The FTE [8], but not exactly the same procedure because of peculiarities in this MSD (thicker cell wall causing a higher apparatus contribution to the FTE).…”

Density measurements on binary mixtures (nitrogen + carbon dioxide and argon + carbon dioxide) at temperatures from (298.15 to 423.15) K with pressures from (11 to 31) MPa using a single-sinker densimeter

“…It basically consisted of a high-pressure measuring cell, which was installed inside a vacuum-insulated two-stage thermostat, a magnetic-suspension coupling incorporated in the measuring cell, and an analytical balance at the top of the apparatus. Both [29], C 2 H 6 [30], N 2 [28], CH 4 [31], natural gases [8,9,15,32,33] 5.0 mK [9] 0.01% of (40 or 200) MPa [28] 0.1% [9] Chamorro (250 to 400) K [25] Up to 20 MPa [25] 0 to 2000 kg/m 3 [25] CH 4 ÀN 2 [34], CO 2 ÀN 2 [10,35], CH 4 ÀCO 2 [36], COÀN 2 [37] 3.9 mK [25] (0.007 to 0.015)% of 20 MPa [25] (0.020 to 0.155)% [25] Kuramoto (293.15 to 473.15) K [22] Designed up to 20 MPa [22] n/a iso-Octane, n-nonane, n-tridecane, water, 2,4-dichlorotoluene, 3,4-dichlorotoluene, bromobenzene [22] 3.0 mK [22] n/a (6.7 to 11.7) ppm [22] Wagner (235 to 520) K [38] Up to 30 MPa [39] (2 to 2000) kg/m 3 [39] Cyclohexane, toluene, and ethanol [39], n-heptane, n-nonane, 2,4-dichlorotoluene, and bromobenzene [40], Ethylene, ethane, and sulfur hexafluoride [38], Ar and N 2 [41], CH 4 and CO 2 [42] 8.0 mK [39] 0 a The uncertainties listed, are just for information purposes and especially those estimated before 1990 are from a current point of view possibly not reliable because (i) the confidence probability was not provided in the original paper; (ii) there was no general standard to declare the measurement uncertainty at that time; or (iii) no complete analysis on the measurement uncertainty was done for these apparatuses. The...…”

Accurate p–ρ–T Data for a Synthetic Residual Natural Gas Mixture (0.95 CH4 + 0.04 C2H6 + 0.01 C3H8) at Temperatures between (135 and 500) K at Pressures to 200 MPa

“…3 Patil et al 4,5 describe the single-sinker MSD, and additional modifications to expand the range of measured temperature have appeared. 6,7 A typical data point results from averaging five individual measurements. The apparatus requires approximately 2 h to equilibrate after changing conditions.…”