Lepidolite cycling roasting defluorination method

Abstract

The invention provides a lepidolite circular roasting defluorination method, achieving the characteristic of thorough defluorination by a process of circularly performing roasting reaction on lepidolite for multiple times in a circulating roasting furnace. The method comprises the following steps: putting lepidolite mineral powder, subjected to crushing disposal, into a primary airflow preheater and a secondary airflow preheater for drying preheating and gas-solid separation, then transmitting into the circulating roaster, and circularly performing a process of roasting defluorination for multiple times with high-temperture combustion gas containing steam, collecting defluorinated ore powder by a cyclone dust catcher, and then transferring into a cooler, and cooling to obtain a finished product. According to the method, the material is circulated for multiple times in the furnace, and makes contact reaction with the high-temperture steam, the heat stability of a system is high, and equipment is long in service life; moreover, the ore powder in the frnace is evenly roasted and defluorinated under the stirring of the high-temperture combustion gas, so the defluorination is thorough;the heat utilization ratio of the whole set of equpment is high, treatment capacity is great, and temperature control is accurate.

Description

technical field [0001] The invention belongs to the technical field of mineral raw material processing, and in particular relates to a method for defluorinating lepidolite by cyclic roasting. Background technique [0002] Lithium has the reputation of "21st century energy metal" and "tomorrow's aerospace alloy". With the development of high technology, lithium, as a green new energy material, is widely used in electric vehicles, lithium-ion batteries and other fields, making the world's demand for lithium and its compounds grow explosively. my country is rich in lepidolite minerals, and the study of new defluorination methods is of great significance to the subsequent lithium extraction industry from ores. [0003] Currently existing ore lithium extraction processes mainly include limestone sintering method, soda ash pressure cooking method, sulfuric acid method, chlorination roasting method and sulfate method. These methods have disadvantages such as high energy consumptio...

AI Technical Summary

Problems solved by technology

Compared with other defluorination methods: such as: defluorination of lepidolite ore in a rotary kiln, there is insufficient contact between the lepidolite material and water vapor, the furnace temperature is not easy to control, the material in the furnace is easy to melt and form rings, the energy consumption is high, the productivity is low, and the equipment occupies There are outstanding problems such as large land area and high maintenance costs; in addition, the defluorination method of fluidized bed roasting has problems such as uneven reaction temperature in the defluorination process and long residence time of materials due to the large bed area in the fluidized bed.

Images