Solid-liquid phase equilibrium for chloride salt systems plays a vital role in the utilization of liquid wastes generated from soda ash production by the Solvay process. The equilibrium data for ternary systems AlCl3-NaCl-H2O, AlCl3-NH4Cl-H2O, and CaCl2-NH4Cl-H2O from 283 to 353 K were determined by a dynamic method. A chemical model for these systems was developed with the mixed-solvent electrolyte model parameterization with the average absolute relative deviation less than 5%. The new model is capable of calculating solubilities of NaCl and NH4Cl in the AlCl3-CaCl2-H2O system, and the average absolute relative deviation of predicted points is less than 6%. The experimental and calculated phase equilibria have been used in developing a recovery method for NaCl and CaCl2 in the liquid wastes from the Solvay process and the subsequent utilization of CaCl2.