The south of Tunisia is a sunny region. This area contains many mineral reserves of natural brines which currently are not well exploited. These reserves are estimated to several millions of cubic meters. They are called sebkhas and chotts, with complex high concentrated solutions. To study these kinds of saline solutions, many authors assimilate them to a quinary system represented by Na+, K+, Mg2+/Cl-, SO42- // H2O. In previous works we noted the insufficiency of classic representations; consequently, we think that the use of computers can help us to resolve this problem. For this purpose the DPAO method was employed to simulate brine evaporation and to foresee the solid phases deposed during the process. The computer allows the hyper-space calculation of all components; therefore, the DPAO is a reliable, universal, and flexible method.