Method for preparing lithium salt ore from plateau sulfate type salt lake brine

Abstract

The invention discloses a method for preparing lithium salt ore from plateau sulfate type salt lake brine. The method comprises the following steps of: evaporating sulfate type salt lake brine to be in the sodium chloride saturated state, freezing in winter to separate out mirabilite, and carrying out solid-liquid separation when the content of the sulfate ion in the brine is controlled to be 1g / L to 7g / L; evaporating the brine from which the mirabilite is separated out, so as to separate sodium chloride; evaporating the brine from which the sodium chloride is separated out, so as to separate out sylvine, carnallite and epsomite, carrying out solid-liquid separation when the lithium ion concentration in the brine is controlled to be greater than or equal to 6g / L, wherein the brine subjected to solid-liquid separation is the brine with high magnesium chloride content; mixing the brine with high magnesium chloride content with the mirabilite to react so as to separate out sodium salt and magnesium salt, and carrying out solid-liquid separation when the magnesium-lithium ratio in the solution is controlled to be less than or equal to 8:1, so as to obtain boron-lithium-rich brine; and reacting the boron-lithium-rich brine with water to separate out boron rock, carrying out solid-liquid separation so as to obtain lithium-rich brine; and introducing the lithium-rich brine into a lithium salt pool, and evaporating so as to separate out the lithium salt ore.

Description

technical field [0001] The invention relates to a development and utilization process of salt lake brine, in particular to a method for preparing lithium salt ore by utilizing plateau sulfate type salt lake brine. Background technique [0002] Lithium, known as the "energy upstart" in the 21st century, is the lightest and most active metal element in nature, and it is a new energy raw material. Lithium resources in nature mainly exist in granite pegmatite deposits, salt lake brine, sea water and geothermal water. [0003] China is one of the countries with the richest salt lake lithium resources in the world. There are a large number of salt lakes on the Qinghai-Tibet Plateau in my country. Among them, the salt lakes in the Qaidam area of ​​Qinghai, such as Chaerhan Salt Lake, Dachaidan Salt Lake, East-West Taijinel Salt Lake, Yiliping Salt Lake, Gasikule Salt Lake, etc., after decades of large investment by the state, infrastructure such as roads and railways The condition...

AI Technical Summary

Problems solved by technology

In the development of these salt lakes, people are unremittingly trying to realize the comprehensive utilization of potassium, lithium, boron, magnesium, sodium and other resources. Some technologies have successfully achieved industrial trial production, but only potassium fertilizer and sodium fertilizer have truly achieved large-scale industrial production. The production of salt and magnesium salt series products has begun to take shape, but the production of boron and lithium is still full of difficulties

[0004] The environmental conditions in the plateau salt lake area are relatively harsh, which seriously affects the development and utilization of salt lake brine. The main reasons are: high altitude. For example, the altitude of the salt lake in Tibet is generally in the range of 4000-5000m, and the highest is over 5000m. The natural environment is extremely harsh and the ecological environment is very fragile. , high environmental protection requirements; inconvenient transportation, for example, the traffic conditions of the salt lake in Tibet are extremely poor, far away from the national highway, the best condition can only be reached by gravel road, and far away from the product market consumption area, the shortest transportation distance is 2000km, most of them are more than 3000km The basic infrastructure is blank, far away from the power grid, and there is no condition for building a large-scale chemical plant. There are no chemical companies and auxiliary facilities available for hundreds of kilometers.

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