Lithium ore exists in two forms. One is lithium ore, such as spodumene, which is mainly distributed in Australia. The other is salt lake lithium ore, that is, salt lake brine, from which lithium is extracted. The current consumables of lithium batteries are mainly lithium carbonate rather than lithium metal. The main process of extracting lithium from ore to prepare lithium carbonate is sulfuric acid method, which is used to produce lithium sulfate and then to prepare lithium carbonate.
It is reported that salt lake brine is one of the important methods to prepare lithium carbonate, but the current comprehensive yield of lithium carbonate extracted from salt lake brine is only about 30%, which can not meet the needs of people. However, recently, there was good news that Tibet Urban Investment Co., Ltd. participated in two pilot projects of lithium extraction from salt lakes of Guoneng Mining, one of which realized the direct preparation of battery grade lithium carbonate from brine in Tibet, providing a new way for efficient and green utilization of lithium resources in carbonate salt lakes in Tibet. The salt lake industry has become a wind outlet this year. With the rapid rise of lithium product prices and technological progress, industrial capital has been heavily involved, and the salt lake industry has ushered in a period of accelerated development.
The common beneficiation methods of lithium ore include hand separation, flotation, magnetic separation, chemical method and multi process combination method. Among them, the flotation method is more widely used and has better separation effect. For the separation method, either the direct flotation method or the reverse flotation method can be selected.
The positive flotation process is the process of preferential flotation of spodumene. The method is to add sodium hydroxide to the pulp at the beginning to stir and scrub to remove surface pollutants, and then conduct flotation separation after desliming and ore washing; The reverse flotation process is carried out in alkaline pulp. Dextrin, starch, etc. are used as spodumene inhibitors, terpineol oil is used as foaming agent, and amine cationic collectors are used to flotation quartz, feldspar, mica and other gangue minerals. The products in the tank are spodumene after removing iron.
