芒硝真空蒸发冷却结晶介稳区宽度研究

提出了利用溴化锂溶液的强吸湿性，以硫酸钠溶液表面水蒸气压力与溴化锂溶液表面水蒸气压力之差为推动力，实现芒硝真空蒸发冷却结晶的方法。基于此方法研究了芒硝介稳区宽度，并用多元线性回归拟合得到了硫酸钠溶液的超溶解度曲线回归方程。实验结果表明：硫酸钠溶液质量分数为9%~24%，芒硝介稳区宽度随着硫酸钠溶液质量分数的增大呈现先变窄后变宽的趋势；提高结晶器的搅拌转速、增加吸收器内溴化锂溶液的浓度，皆使芒硝介稳区宽度变窄。该研究可为芒硝真空蒸发冷却结晶的工程设计提供参考。

Study on metastable zone width of glauber salt′s vacuum evaporation cooling crystallization

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.