Lepidolite ore and sodium sulfate roasting and leaching method

Abstract

The invention belongs to the technical field of extraction of lithium from ore, and particularly relates to lepidolite ore and sodium sulfate roasting and leaching method. The lepidolite ore and sodium sulfate roasting and leaching method comprises the following steps of: step (1). processing raw materials, and finely grinding sodium sulfate, calcium oxide, calcium carbonate and a rubidium and cesium displacer to a set degree; step (2). mixing, to be specific, uniformly mixing lepidolite concentrate powder with the sodium sulfate, the calcium oxide, the calcium carbonate and the rubidium and cesium displacer finely ground in the step (1) according to the set ratio; step (3). calcination, to be specific, calcining the above mixture at the temperature of 850 to 1000 DEG C to obtain a calcined clinker called calcine; step (4). finely grinding; step (5). transferring the finely ground calcine to a leaching tank, and leaching lithium and rubidium in the calcine; and step (6). mixing leaching residues with a set amount of water, stirring and washing at a set temperature, and washing out lithium, rubidium, and cesium in the leaching residues. According to the technical solution of the lepidolite ore and sodium sulfate roasting and leaching method, potassium sulfate is not used; and only single sodium sulfate is used, is a by-product of a lithium carbonate precipitation process, and does not need to be purchased, thus, the reagent cost is reduced, and the sulfate roasting technology has economical efficiency.

Description

technical field [0001] The invention belongs to the technical field of extracting lithium from ores, in particular to a method for roasting and leaching lepidolite sodium sulfate. Background technique [0002] Due to the development of electric vehicles, the demand for lithium batteries in the global market continues to rise, resulting in a rapid increase in the demand for lithium. How to develop and utilize various lithium resources to prepare lithium carbonate to meet the market demand for lithium carbonate is in front of us. urgent task. [0003] Lithium exists in nature in two forms: solid mineral resources and liquid deposit resources. Solid mineral resources are further divided into spodumene minerals and lepidolite minerals. China's spodumene mineral resources are relatively scarce, but lepidolite is very rich. The reserves of lepidolite in Yichun, Jiangxi Province are huge, and the lithium reserves (calculated as lithium oxide) are 2.578 million tons. Lepidolite al...

AI Technical Summary

Problems solved by technology

[0013] The traditional kraft roasting method generally uses a single potassium sulfate, or mainly mixes potassium sulfate with less sodium sulfate or other sulfates. Potassium sulfate is expensive, and the cost of reagents is high, and lithium sulfate is easy to produce due to the high concentration of potassium in the leaching solution. Potassium double salt precipitation limits the increase of lithium concentration, so the traditional lithium mica sulfate roasting process for lithium extraction has little industrial application value

The current sulfate roasting lithium extraction process is to reduce the amount of potassium sulfate as much as possible and increase the amount of sodium sulfate. On the premise of ensuring the lithium leaching rate, the reagent cost of potassium sulfate should be reduced as much as possible. However, after increasing the amount of sodium sulfate, the calcined sand will be sintered. Even melting, resulting in the impossibility of industrial operation, and the leaching rate of rubidium and cesium is very low

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