Method and roasting device for roasting lithium salt by using spontaneous combustion of lithium ore as heat source

Abstract

The invention discloses a method and a roasting device for roasting and making lithium salt by taking spontaneous combustion of lithium ores as a heat source. According to the method, the lithium oresare served as raw materials, the lithium ores and roasting auxiliary materials are mixed to serve as spontaneous combustion materials, and then roasting is carried out. The combustible is added intolithium ore powder according to a composite salt method formula, the combustible and the lithium ore powder are mixed and squeezed into spherulites, columns, cylinders, plates, bricks or the like witha uniform shape, the squeezed materials are placed uniformly into a tunnel kiln material trolley by adopting a tunnel kiln, the material trolley continuously passes through the tunnel kiln for roasting the materials, the combustible in the formed materials carries out the spontaneous combustion in the roasting process, and the temperature of the materials is enabled to be consistent. The method and the device solve the problem of a rotary kiln crusting phenomenon, the problem of undercooked materials is well solved by means of formed agglomeration squeezing and spontaneous combustion inside the agglomeration body, so that the lithium recovery rate is high, meanwhile, the yield is large, the energy consumption is low, the process is stable and easy to operate, and the production process issimple.

Description

Technical field: [0001] The invention relates to a method and a device for extracting a lithium salt solution, in particular to a method and a roasting device for roasting lithium salt by using lithium ore as a raw material and using lithium ore spontaneous combustion as a heat source. Background technique: [0002] Lithium sulfate is an important basic raw material for the development of new energy sources for lithium batteries, and its production and demand are increasing, and its price is getting higher and higher. [0003] Lithium salts such as lithium carbonate, lithium hydroxide, lithium sulfate and lithium chloride are important raw materials for the preparation of new energy lithium-ion batteries. At present, when lithium ore is used as the raw material for the production of lithium salt, the rotary kiln roasting is usually used to extract lithium. Although the above-mentioned roasting method is relatively mature, there are obvious process defects that affect industr...

AI Technical Summary

Problems solved by technology

At present, when the lithium ore used to prepare lithium salt is used as a raw material for production, the process of extracting lithium by roasting in a rotary kiln is usually used. Although the process using the above-mentioned roasting method is relatively mature, there are obvious process defects that affect industrialization: First, Lithium ore is in the form of powder, and kiln caking phenomenon is very easy to occur during the roasting process. If it is directly roasted without pre-drying, the kiln caking phenomenon will be more serious, and the energy consumption will be large, resulting in unstable and continuous production of the kiln, and the output is very low. It is difficult to release, and the annual output is also low, but thousands of tons; the reason is that the kiln cannot produce stably and continuously, and the phenomenon of raw material and kiln knotting often occurs during the calcination process

Very unstable production

Second, when lithium ore powder is roasted, it is easy to accumulate and agglomerate, and it is difficult to balance the heating temperature of the material, so raw material is easy to appear, which directly affects the recovery rate of lithium.

Therefore, it is necessary to solve the problems of material agglomeration and uneven temperature through continuous turning of the rotary kiln. However, this measure not only increases the power consumption of turning, but also limits the amount of roasting per unit time. The inter-heat conduction is slow, so it is necessary to prolong the calcination time or increase the calcination temperature appropriately, which will further aggravate the kiln knot phenomenon, increase the distortion of the furnace temperature, and make the calcination process difficult to control

In addition, the lithium ore powder is prone to dust pollution during the roasting process of the rotary kiln. At the same time, the lithium ore powder in the form of dust is absorbed during the tail gas treatment of the roasting process, which increases the loss of lithium ore powder

Disadvantages such as low metal recovery rate

At the same time, there are large material circulation, low equipment efficiency, high energy consumption, and kiln knot phenomenon.

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