Crystallization path of natural brine evaporation using the DPAO method Original Research Article

Understanding the full scope of the diagram representing saline solutions and the thermodynamics of the phase relationships is important for obtaining the most cost-effective process design for industrial salt recovery technology from salt lake resources. In previous works, we have shown that modeling electrolyte systems using the DPAO method can help us to represent the chemical compositions of highly concentrated solutions of natural brines extracted from two Tunisiansalt lakes, Sebkha and Chott. This simulation shows good agreement with classic representations but with the advantage that this method allows all the system components to be added without changes or approximations. The aim of this work is computing the chemical composition changes of a given initial solution and the number of moles of salt precipitated along a progressive concentration of brine solution by evaporation with DPAO, then to determine crystallization paths of a mineral assemblage reacting with water, and finally to compute the mineral quantities precipitated as well as chemical composition of solutions at different reaction progress rates. A comparison between experimental and predicted results was made to test the validity of the new approach and to develop evaporation sequences for the recovery of desired products. This simulation method helps to establish rules to navigate through the diagrams and to draw crystallization paths with the algebraic solution of material balances.