Figure 6.01. H2O-NaCl-KCl Diagram. Ternary phase diagram for the system H2O-NaCl-KCl at 20°C and 0.1 MPa pressure based on data from Gevantman (1971, Fig. 2.4). The diagram shows possible brine compositions (colored blue) limited by saturation curves (liquidus curves) for both halite (Hl) and sylvite (Syl). The two saturation curves meet at a point that gives the brine composition for a liquid saturated with both halite and sylvite. For bulk compositions beyond the saturation curves, the system may be a two-phase mixture of brine + halite, a two-phase mixture of brine + sylvite, or a three-phase mixture of brine + halite + sylvite. Click on the "Coordinates" button to see the chemical compositions of points in the diagram in weight percent as the mouse is moved over the diagram.
