Abstract: It presented the use of water vapor pressure difference between the surface of lithium bromide solution and that of sodium sulfate solution as the driving force to achieve vacuum evaporation cooling crystallization of glauber salt.This method is based on the strong moisture absorption of lithium bromide solution.Based on this method，the glauber salt metastable zone width was studied，and the sodium sulfate solution super-solvus regression equation by multiple linear regression was obtaained. The results showed that：when the mass fraction of sodium sulfate was between 9% and 24%，glauber salt metastable zone first decreased and then increased with increasing mass fraction of sodium sulfate；and the metastable zone decreased with the in- creasing stirring speed of crystallizer and the concentration of lithium bromide in the absorber.This study could provide a re- ference for engineering design of glauber salt vacuum evaporation cooling crystallization.

Key words: glauber salt, vacuum evaporation, crystallization, metastable zone