At present, lithium resources around the world are in urgent need, and the mining and processing of spodumene, lepidolite and salt lake lithium are accelerated in many places. Lithium extraction from spodumene has become an important method due to its simple process and low investment cost. The main purpose of lithium ore dressing is to remove impurities in lithium ore and increase the content of lithium oxide in lithium ore. If spodumene ore contains feldspar, how should we separate it? Here we introduce the separation method and process flow of spodumene and feldspar.
In this project, the main mineral of lithium ore is spodumene, the gangue mineral is feldspar, accompanied by magnetic iron impurities, and the content of harmful elements such as sulfur and phosphorus is low. The separation methods of spodumene and feldspar can be flotation, magnetic separation, etc. For this batch of lithium ores, Xinhai has conducted a beneficiation test and analysis, and finally determined the process flow of crushing grinding desliming flotation magnetic separation.
Separation process of spodumene and feldspar:
According to the principle of "more crushing and less grinding", the three-stage and one closed circuit crushing process is adopted in the crushing stage, and the ore crushing particle size is controlled below 15mm. The selected equipment is two jaw crushers for coarse crushing and intermediate crushing, one cone crusher for fine crushing, and one round vibrating screen for screening.
Process flow in crushing stage: the raw ore is fed from the raw ore bin to the first section crusher by the feeder for coarse crushing, and the crushed product is fed to the second section crusher by the 1 # belt conveyor for intermediate crushing. The crushed product is transported to the circular vibrating screen by the 2 # belt conveyor for screening. The screened material is returned to the second section crusher by the 3 # belt conveyor for re crushing, while the screened material is transported to the third section crusher for fine crushing, and the crushed product is sent to the storage bin, Prepare to enter the next stage of grinding. The process in this stage not only reduces the energy consumption of grinding, but also avoids the sliming caused by large fluctuation of feed particle size and continuous grinding.
A grinding process is adopted in the grinding and classification stage of spodumene, and a wet lattice ball mill and spiral classifier are configured.
Process flow of grinding stage: the materials are transported to the ball mill by pump from the feed bin for grinding, the products after grinding enter the classifier for classification, the overflow returns to the ball mill for regrinding, and the underflow is sent to the next stage for desliming.
Spodumene desliming process adopts inclined plate thickener for desliming. After the thick mud sliding along the inclined plate enters the lower cone, it is compressed for dehydration and discharged by gravity to realize desliming operation.
The products after desliming enter the flotation operation. The flotation process of spodumene adopts a coarse one sweep three fine flotation process.
Process flow in the flotation stage: Before entering the flotation, the thickener overflow pulp is first fed into the stirring tank, and at the same time, the dosing agent is mixed evenly before being fed into the flotation machine to complete the flotation process of one roughing, one sweeping and three finishing. In the concentration stage, the SF flotation machine is used, and the middlings are returned in turn to obtain qualified spodumene concentrate. After flotation, the tailings enter the magnetic separation stage, and the feldspar concentrate with high purity (relatively white) is obtained by magnetic separation to remove iron.
In the magnetic separation stage, the process flow of one stage weak magnetic separation - two stages strong magnetic separation is adopted. The main purpose of the process in this stage is to remove iron from the tailings after flotation by magnetic separation to select feldspar ore with high purity. In order to enhance the effect of iron removal, high frequency fine screening is carried out to separate the slag before magnetic separation, and then feldspar powder is obtained after one time of magnetic separation and two times of strong magnetic separation.
Through the above five processes, spodumene and feldspar are well separated, and the production index is stable, the economic benefit is good, and the recovery rate of spodumene is high. The whiteness of feldspar powder can reach 62.0%, and the ideal production index is obtained.
