Abstract: Many processes generate wastewater streams rich in sulfate and chloride. These salt components are traditionally not recovered and are discharged to the environment. The invention recovers pure water for recycle/reuse and simultaneously generates valuable pure salts of NaCl and Na2SO4 for beneficial reuse, eliminating the waste stream. Process consists of the sequential crystallization of salt products with an intermediate purification step in which a chemical reactant is added to elevate levels of purity. The process is configured to simultaneously achieve zero liquid discharge.

Abstract: A sodium chloride recovery method for upgrading a mixed salt stream from lower sodium chloride purity to an increased sodium chloride purity is provided. The salt recovery method utilizes the solubility properties of the impurities in the mixed salt to preferentially dissolve them over sodium chloride. As the impurities are removed from the solid phase using a salt stripper, sodium chloride rich slurry is generated. The rich salt slurry is processed by an upgrader to remove the remaining impurities. The upgraded sodium chloride slurry is dewatered and washed in the phase separator to generate sodium chloride salt at a higher purity.

Abstract: Many processes generate wastewater streams rich in sulfate and chloride. These salt components are traditionally not recovered and are discharged to the environment. The invention recovers pure water for recycle/reuse and simultaneously generates valuable pure salts of NaCl and Na2SO4 for beneficial reuse, eliminating the waste stream. Process consists of the sequential crystallization of salt products with an intermediate purification step in which a chemical reactant is added to elevate levels of purity. The process is configured to simultaneously achieve zero liquid discharge.