Experimental study on concentration of winter brines in Zabuye Salt Lake, Tibet

Based on the local conditions, a new idea of combining the method of multi-level natural freezing-separation and natural solar evaporation-concentration is proposed to guide the experiment. The method fully uses the unique cold resources and solar resources on the Tibetan plateau. During the experiment, solid and liquid are separated after freezing of brines. The residual brines are subjected to solar evaporation and again frozen and separated, and this operation is repeated multiple times. The results of the experiment show that, after multi-level freezing and solar evaporation, the concentration of lithium ions in the brine goes up from 0.957 g/L at first to 7.97 g/L in the brines at last. This value is more than double the highest value of 2.8 g/L got by natural solar evaporation, and that the CO2-3 content decreases from 20.2% to 11-14%. This experiment makes it possible to provide good-quality brines for the large-scale extraction of Li2CO3 of industrial value and furnishes a scientific experimental basis for the establishment of a complete optimum technological process.