Sea water bitterns (SWB) are encountered in the processes of desalination and sea-salt production where large quantities of bitterns and brines are produced, either as by-products, or as waste products. They could be described as “exhausted brines”. In theory, for every ton of sea-salt produced about one cubic meter of bittern is produced and is available for further processing. To exploit valuable salt products, in particular MgCl2 from sea water in desalination plants and/or salt production, various methods were carried out, in particular by the author and his colleagues. Mainly they consist in applying the physical concept of preferential-type of salt separation, where Mg Cl2 is the most soluble salt, will separate at the very end. An experimental work was initiated by Kettani and Abdel-Aal and extended by Abdel-Aal et al. Two case studies are presented and discussed in this paper.