A. Process flow of lithium carbonate extraction from lithium ore
1、Roasting section
Conversion roasting: Lithium pyroxene concentrate is added to the end of the lithium carbonate rotary kiln, and the concentrate is dried with high temperature gas in the preheating section at the end of the kiln, and the concentrate is crystallized and roasted at a temperature of about 1200℃ in the calcination section.
Acid roasting: The roasted material is cooled down in the cooling section and discharged from the kiln head, then naturally cooled and ground by the ball mill to 0.074mm particle size above 90%, then transported to the tailing bin of the acid roasting kiln, added to the acid mixer and mixed with concentrated sulfuric acid in a certain ratio, and reacted with sulfuric acid to get acid clinker.
Slurry leaching and washing: The clinker is cooled and slurried, so that the soluble lithium sulfate in the clinker is dissolved into the liquid phase, and the leaching residue is attached to the liquid containing lithium sulfate, in order to reduce lithium loss, the leaching residue is washed by reverse stirring, and the washing liquid is returned to slurry leaching.
Leaching solution purification: In the leaching process, although some of the impurities in the clinker can be removed, leaching solution purification using the alkaline decalcification method to remove the calcium in the leaching solution and the calcium brought in by the alkalizing agent lime milk. The alkaline decalcification slurry is separated by liquid-solid separation, the resulting solution is the purification solution, the filter cake is the calcium slag, return to the slurry leaching.
Evaporation and concentration of purification solution: use sulfuric acid to adjust the purification solution to pH6~6.5, evaporation and concentration by three-effect evaporator, so that the concentration of lithium sulfate in the concentrated solution reaches 200g/L. The concentrated solution is separated by pressure filtration, the filtrate is the finished liquid for the next process, and the filter cake is the finished slag returned to the slurry leaching.
Lithium carbonate
2、Lithium carbonate production section
The finished liquid and soda ash are added to the evaporation lithium sink for lithium evaporation, and the lithium precipitation is separated from the primary crude lithium carbonate (containing less than 10% filtrate) and the primary lithium sink mother liquor by centrifuge while it is hot. Secondary lithium precipitation, the secondary crude product and secondary mother liquor, sodium precipitation mother liquor back to the deployment of the primary mother liquor.
Primary crude lithium carbonate and secondary crude attached liquid containing impurities such as Na2SO4, and then stirring and washing with clean water, washing liquid sent to the alkali, washing with a centrifuge to separate the wet fine lithium carbonate while hot, and then dried by far-infrared dryer, magnetic separation to remove the dryer off the wire shavings and other debris, and then crushed by airflow, packaging into storage.
3、Anhydrous lithium chloride section
The finished liquid from the roasting section is separated from the calcium chloride solution by complex decomposition reaction, and the solid NaCl is separated to get LiCl concentrated solution. the LiCl concentrated solution is transported to the refining kettle, and the LiCl finished liquid is obtained after separation, and the finished liquid is spray dried to get the anhydrous lithium chloride product with uniform particles.
B. How is the lithium ore milling process realized?
Lithium ore powder making can use LUM vertical mill, which adopts the ultra-fine grinding process and develops a new type of grinding equipment, suitable for ultra-fine grinding of various non-metallic minerals, such as lithium mica, calcite, marble, dolomite, etc.
LUM ultrafine vertical mill is mainly composed of electric motor, reducer, grinding roller device, grinding disk device, pressurizing device, powder selector, body and oil station.
The main motor drives the grinding disc through the reducer, while the wind enters the mill through the air inlet, and the material falls in the middle of the grinding disc through the screw feeder downcomer. Under the action of centrifugal force, the material moves evenly from the middle to the edge of the grinding disc, and when it passes through the grinding roller channel area on the grinding disc, it is crushed by the grinding rollers, and the large pieces of material are directly crushed, and the fine-grained material is squeezed to form a material bed for intergranular crushing. The crushed material continues to move to the edge of the grinding disc until it is taken away by the strong airflow at the wind ring, while the larger granular material falls back to the grinding disc to continue to be crushed, and the material in the airflow passes through the upper separator, under the action of the rotor blades, the coarse particles return to the grinding disc for grinding, and the qualified fine powder comes out of the mill with the airflow and is collected by the powder collector of the system, and the collected powder is the ultra-fine vertical grinding product. Iron and other debris mixed into the material with the movement of the material to the edge of the grinding plate, because of its own weight and can not be blown up by the wind, fell to the lower cavity of the mill is installed in the bottom of the grinding plate scraper scraping into the slag discharge mouth out of the machine.
If you are interested in our products please call us at 0086-371-67997088 or click Business Link Online We will be online 24 hours a day, welcome to call. Our customer service staff will provide you with detailed answers, thoughtful service, will be happy to provide you with product information and application knowledge, so that you can not only get valuable equipment, but also get our attentive service.
