Sea-water solubility phase diagram. Application to an extractive process

The main goal of this presentation is to tentatively forecast or improve an extrac- tive process. The sea-water system is described using a graphical representation of the quinary ion-pair system Na + , K + , Mg 2+ / Cl - , SO 4 2- // H 2 O. The operations required by extraction or purification of a sea-water component are simulated by a path through the sol- ubility diagram. The procedure is applied to isothermal evaporation of Black Sea water at 25 °C, and the balance of the crystallization sequence is determined. In the same way, the cooling of residual brine, after precipitation of pure sodium chloride, is studied.