西藏藏北某盐湖卤水5℃等温蒸发实验研究

西藏藏北某碳酸型盐湖卤水富含有价元素Li、K、B和微量元素Rb、Cs等。为更好地了解该盐湖卤水在自然条件下的蒸发结晶规律,根据当地气候条件等,需对相应卤水进行低温室内等温蒸发实验研究。实验对该碳酸型盐湖夏季卤水进行了5℃等温蒸发实验,并参考Na＋、K＋//Cl-、SO24-、CO23-—H2O五元体系（25℃）介稳相图研究了该卤水5℃等温蒸发过程中盐类结晶路线和析出规律,结果表明：通过前处理工艺,有效改善了原卤组成和析盐行为,使锂的富集更为集中,实际析盐顺序为：NaCl、NaK3（SO4）2、Li2CO3和KCl,为该碳酸型盐湖卤水的综合开发利用提供了重要的依据。

Exporimental Study on Isothermal Evaporation at 5 C with Carbonate- type SahLake Brine in North Tibet

The special elements Li, K, B and trace elements Rb, Cs are contained abun- dantly in carbonate - type Salt Lake brine in North Tibet. In order to mow the crystallization rules of salt minerals at ambient temperatures, it is necessary to carry out an isothermal evaporation experi- ment at lower temperatures according to the location Climatic conditions. Referring to the metastable phase diagram of Na~ ,K ~//C1- ,SO~- ,CO~- - H20（25 ~C ） quinary system, the isotheral evapo- ration experiment of the summer brine in the salt lake of Tibet is carried out at 5 ~C. The crystalliza- tion route and seperation rules of salts are studied during the isothermal evaporation process. It indi- cates that the raw brine composition and separation behavior is improved effectively and the lithium comcentration is enriched after brine is pre - treated. The actual separation sequence of salt is： NaC1, NaK3 （SO4）2, LiCO3 and KC1. Those be important basis to muhipunpose utilization of the carbonate -type salt lake brine.