Article : Dessalement efficace au gel des suspensions des eaux usées de la mine pour séparer l'eau propre et les sels

19 février 2018
Types d'actualités

Environ. Chem. Lett (2016), N° 14

Suspension freeze desalination is a promising technique for producing clean water from mine wastewaters. The principle is that growing ice crystals reject impurities during freezing. As a result, pure water is separated from mine wastewaters as clean ice. Actually, there is a need for improved techniques to increase water yield and purity. Here we tested ice formation in complex synthetic solutions during cool ing and addi tion of seed.
Solutions included: pure distilled water, 50, 33 g/L NaCl and 17, 50 g/L Na2SO4, 50 g/L NaCl and 50 g/L Na2SO4.
Results show that heat of crystallization was the highest with pure distilled water at 8859 J, whereas the lowest heat of crystallization, of 4608 J, was for the solution of 50 g/L NaCl and 50 g/L Na2SO4, indicating that the presence of the salt enhances ice formation. As an application, we designed a new flow diagram, which, in addition to heat exchanger and ice filter, now includes a fluidized bed reactor for salt crystallization and recovery, and a separate heat exchanger for ice crystallization.