SEQUENCE CRYSTALLIZATION DURING ISOTHERM EVAPORATION OF SOUTHERN ALGERIA CHOTT BAGHDAD NATURAL BRINE

Southern Algerian's natural brine sampled from chott Baghdad may be a source of mineral salts with a high economic value. These salts are recoverable by simple solar evaporation. Indeed, during isothermal solar evaporation, it is possible to recover mineral salts and to determine the precipitation sequences of different salts as a function of the chemical composition and the density of the brine. In this study, the variation of ionic composition of concentrated brine during isothermal evaporation was measured; then the experimental pathway of the point representing its composition on the oceanic fivefold diagram Na + , K + , Mg 2+ , Cl - , SO 4 2- //H 2 O was plotted. In order to follow the precipitation sequences of mineral salts, during solar evaporation at 35°C, X-Ray diffraction was performed on the precipitated and removed salts from the brine during evaporation. Keywords: seawater quinary diagram, Janecke projection, isothermal evaporation, mineral salts, chott Baghdad brine