Method for solving argillization of acid-mixed amblygonite

Abstract

The invention discloses a method for solving acid-mixed argillization of amblygonite. The problem that industrialization cannot be realized due to rapid argillization and hardening of materials in the acidification process of amblygonite is solved by adopting industrial-grade diatomite. Particle crushing and powder selecting are completed on the amblygonite particles through a ball mill and a powder selecting machine, sulfuric acid and materials are mixed through acid mixing equipment, kieselguhr is added into the acid mixing equipment according to the water content ratio of the materials, the materials are fed into an acidification roasting kiln in a loose state after multiple times of stirring, acidification roasting is completed on the acidified materials in a rotary kiln, and the materials are recycled. And the roasted material is subjected to ball milling and then is leached, the lithium content of leached slag is within 0.30%, the lithium leaching yield is 89% or above, and the amblygonite leaching section is completed.

Description

Technical Field

[0001] The present invention relates to the field of spodumene treatment, and specifically relates to a method for solving the problem of spodumene turning into sludge after mixing with acid. Background Art

[0002] After spodumene is mixed with acid, the material turns into sludge due to the water absorption of concentrated sulfuric acid, and the hardening caused by the water absorption of aluminum sulfate / lithium sulfate leads to the inability to industrialize the acidification roasting process of spodumene. There are mainly 4 methods in the prior art to solve the problem of turning into sludge after mixing with acid: using fly ash, calcium sulfate, sodium sulfate or pre-calcination. Among them, fly ash will increase the sulfuric acid consumption; calcium sulfate and sodium sulfate will increase the salt content in the leaching solution and reduce the liquid quality; pre-calcination requires a large amount of natural gas consumption and high cost. In view of these problems, diatomite is used in this paper to solve these problems. First, the inward water absorption of diatomite ensures that spodumene will not turn into sludge for a period of time. Diatomite can also make the acid-mixed material more fluffy, which is helpful for the conversion of lithium during acidification roasting; second, sulfuric acid will not react with diatomite to increase the sulfuric acid consumption, and no impurity elements will be introduced into the leaching system; third, there is no need to use pre-calcination to increase the cost. The addition amount of diatomite is up to 2.5% of the total amount of spodumene, and the use cost is relatively low. Summary of the Invention

[0003] In order to overcome the problems existing in the prior art, the present invention uses diatomite to solve the problem of spodumene turning into sludge after mixing with acid. Because the main component of diatomite is silicon dioxide, it will not react with sulfuric acid to increase the consumption of auxiliary material sulfuric acid. The water absorption and larger pore size of silicon dioxide can make the material after mixing with acid more fluffy, and the excess water in the acid mixing kettle is locked by diatomite; nor will it introduce other impurities to reduce the liquid quality.

[0004] The present invention provides a method for solving the problem of spodumene turning into sludge after mixing with acid. During the acid mixing process, adding diatomite can prevent the spodumene after mixing with acid from turning into sludge within 1 hour.

[0005] Further, the diatomite is industrial-grade diatomite, which is weakly alkaline, with a main content of more than 85% and a moisture content of within 1%.

[0006] Further, 98% concentrated sulfuric acid is used during acid mixing.

[0007] Further, during acid mixing, the mass ratio of diatomite to spodumene material ≤ 2.5%.

[0008] Further, the addition amount of concentrated sulfuric acid is 1.5 times - 2 times the lithium molar equivalent in spodumene.

[0009] Further, before mixing spodumene with acid, it needs to be crushed first, and a ball mill and a powder separator are selected for crushing.

[0010] Further, the moisture content of spodumene after crushing is controlled within 1%.

[0011] Further, adding diatomaceous earth during the acid mixing process can make the material after acidifying spodumene fluffier, which is more conducive to roasting, and can make the lithium leaching yield of the material after acidifying spodumene above 89%.

[0012] Beneficial effects: The present invention uses diatomaceous earth to solve the problem of spodumene turning into sludge during acid mixing. The main component of diatomaceous earth is silicon dioxide, which does not react with concentrated sulfuric acid, will not increase the amount of sulfuric acid used, controls the amount of diatomaceous earth within 2.5%, and has almost no impact on the leaching yield; the water absorption and larger pore size of silicon dioxide can make the material after acid mixing fluffier, and the excess water in the acid mixing kettle is locked by diatomaceous earth; it will not introduce other impurities to reduce the liquid quality. For 1 ton of lithium carbonate equivalent, the cost of using diatomaceous earth is within 200 yuan, and the use cost is relatively low; using diatomaceous earth can increase the amount of spodumene used in acid mixing, which is beneficial to improving the leaching rate, and can ensure that the lithium leaching yield of the material after acidifying spodumene is above 89%. Specific embodiments

[0013] The present invention will be described in detail below with reference to the embodiments. Example 1

[0014] A batch of 150 tons of spodumene material with a lithium content of 2.83%, a moisture content of 0.50%, and particle size of irregular small particles of 0.30 cm passes through a ball mill and a powder separator to achieve a 200-mesh 80% sieve passing rate target. According to 500±20 kg of the material, 12.5 Kg of diatomaceous earth is added, and 98% concentrated sulfuric acid is added according to 1.5 times the lithium content. After 5 minutes of grinding, the mixing of 98% sulfuric acid and the material is completed. The material after acid mixing is fluffy and has no lumps. Cooling water is used to control the acid mixing equipment within 85 degrees, and it is sent to the acidification kiln through a conveying device. It is controlled at 280 - 300 degrees in the heating zone, the main kiln speed is 9HZ, the cooling kiln speed is 10HZ, and it is ground to 80 mesh with an 80% sieve passing rate, and then sent for water leaching. Calcium carbonate is used to adjust the pH between 4.0 - 5.0, and a filter press is used to complete the solid-liquid separation. The average lithium content in the slag is 0.30%, the dry slag ratio is 1.0:1, and the lithium leaching yield is 89%. Example 2

[0015] A batch of 200 tons of spodumene materials with a lithium content of 3.40%, a water content of 0.25%, and irregular small particles with a particle size of 0.20 cm pass through a ball mill and a powder separator to achieve a 200-mesh 80% sieve passing rate target. According to the material of 500±20 kg, the amount of diatomaceous earth added is 10 kg, and 98% concentrated sulfuric acid is added according to 1.8 times the lithium content. After 8 minutes of grinding, the mixing of sulfuric acid and materials is completed. After acid mixing, the materials are fluffy and without caking. Cooling water is used to control the acid mixing equipment within 85 degrees, and then it is transported to the acidification kiln by belt. The heating zone is controlled at 290-320 degrees, the main kiln speed is 8HZ, and the cooling kiln speed is 10HZ. After grinding to 80 mesh and 80% sieve passing rate by a small ball mill, it is sent for water leaching. Calcium carbonate is used to adjust the pH between 4.0-5.0, and a filter press is used to complete the solid-liquid separation. The average lithium content in the slag is 0.29%, the dry slag ratio is 1.10:1, and the lithium leaching yield is 90.6%.

Claims

1. A method for solving the problem of spodumene acid-slurry sludging, characterized in that During the acid mixing process, adding diatomaceous earth can prevent the spodumene material after acid mixing from becoming muddy and caking within 1 hour.

2. The method for solving the problem of spodumene mud formation during acid mixing according to claim 1, wherein, The diatomaceous earth is industrial-grade diatomaceous earth, which is weakly alkaline, with a main content of more than 85% and a moisture content within 1%.

3. A method for solving the problem of sludging of spodumene with acid as claimed in claim 2, characterized in that, 98% concentrated sulfuric acid is used during acid mixing.

4. A method for solving the problem of sludging of spodumene with acid as described in claim 3, characterized in that, During acid mixing, the mass ratio of diatomaceous earth to spodumene material ≤ 2.5%.

5. The method for solving the problem of spodumene mudification in mixing with acid according to claim 4, characterized in that, The addition amount of concentrated sulfuric acid is 1.5 to 2.0 times the lithium molar equivalent in spodumene.

6. The method for solving the problem of slime formation of spodumene with acid according to claim 5, characterized in that, Before acid mixing of spodumene, it is necessary to first crush and select powder using a ball mill and a powder separator. The material passes through a 200-mesh sieve with a screening rate of 80%.

7. A method for solving the problem of sludging of spodumene with acid as described in claim 6, characterized in that, The moisture content of spodumene after crushing is controlled within 1%.

8. A method for solving the problem of sludging of spodumene with acid as described in claim 7, characterized in that, Adding diatomaceous earth during the acid mixing process can make the material after acidification of spodumene fluffy, which is more conducive to roasting, and thus ensure that the lithium leaching yield is above 89%.