A Simple Formula for Saturation Temperature/Pressure of NaCl Solutions

Abstract

The saturation temperature and pressures of NaC1 solutions throughout the geothermally interesting range can be calculated by psia = exp [6.7028-5.52x10/-7(ppm Ca) - 3712/F+4601)] Results of this equation agree with tabular data generally to within +2.5 percent of psia for NaC1 concentrations up to 15 weight percent at 300°. At higher NaC1 concentrations different sets of tabular data are themselves out of conformance while the equation yields intermediate values. This equation can be adapted to mixed salt brines and to dynamically flashing systems by including modifiers for just the second term in brackets.