Gravity-flotation synergistic recovery stage grading process for tin-containing spodumene ore

Abstract

The invention discloses a reselection-flotation synergetic recovery stage grading process for tin-containing spodumene ores, stage separation is realized by adopting a reselection-flotation synergetic beneficiation method, the process is efficient and green, ore properties such as specific gravity, granularity and dissemination relationship of the tin-containing spodumene ores are fully utilized, metal loss of lithium and tin caused by over-grinding is avoided, and the quality of the tin-containing spodumene ores is improved. And meanwhile, recovery of spodumene and associated cassiterite in coarse and fine particle fractions is achieved through the dense medium mineral separation, reselection and flotation processes, minerals in different particle fractions are recovered in a stepped mode under the optimal equipment environment and technological parameters, and valuable metal resources such as tin and lithium are recovered to the maximum extent. In addition, the invention creatively provides the method for recycling tin through reselection of the lithium concentrate smelting slag, and full recycling of resources can be truly achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ore dressing, and particularly relates to a gravity-flotation collaborative recovery stage separation process for tin-bearing spodumene ore. Background Art

[0002] Lithium is the metal with the lightest mass and the largest energy density in nature, and has important applications in the fields of lithium batteries, nuclear energy, glass, etc. With the soaring demand for clean energy, lithium has become a strategic resource. Lithium resources mainly include lithium-containing salt lakes and lithium-containing ores. Among them, spodumene has large reserves and wide distribution, and is the most widely mined ore type. Flotation is the main process for the separation and enrichment of spodumene. In addition to the flotation process, the separation methods of spodumene also include the heavy medium method, which can save the ore dressing cost and improve the comprehensive utilization rate of resources. At the same time, most spodumene ores contain associated metal tin, which is also an important element that needs to be comprehensively recovered.

[0003] Chinese Patent Application CN118403729A discloses a heavy medium beneficiation process for lithium ore to extract and refine and discard waste. This process makes full use of the principles of early discarding and less grinding, but ignores the comprehensive recovery and utilization of valuable elements in the fine-grained tailings. International Patent Application WO2024212608A1 discloses a full-size heavy medium ore dressing system and ore dressing method. This method realizes the heavy medium separation of coarse and fine-grained spodumene and fine-grained flotation, but this process only considers the recovery of spodumene. The over-crushing of associated metals during the crushing and grinding process may lead to poor enrichment effect at the back end. The spodumene ore dressing processes disclosed in Chinese Patent Applications CN117443555A and CN117583118A enable spodumene to be recovered by gravity separation and flotation, which can reduce the process cost, but ignore that there are valuable metals that have been monomer-dissociated in the -0.5mm fraction, and this part can be recovered in advance. Chinese Patent Application CN117065916A discloses a method for the comprehensive recovery and utilization of lithium slag. Under classification treatment, lithium concentrate and tantalum and niobium are recovered by flotation, realizing the efficient comprehensive recovery and utilization of lithium slag, but this process ignores the gravity separation recovery of cassiterite in the smelting slag. Chinese Patent Application CN116532235A discloses a method for the comprehensive utilization of spodumene smelting slag resources. This process can recover lithium, tantalum, and niobium in the lithium slag, but also ignores the separation and recovery of cassiterite in the smelting slag. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention aims to provide a gravity-flotation collaborative recovery stage separation process for tin-bearing spodumene ore, which makes full use of the differences in specific gravity and interfacial properties among spodumene, cassiterite, and gangue minerals, and recovers lithium and tin in spodumene ore and its smelting slag through gravity separation-flotation collaboration, realizing the green and maximum recovery and utilization of resources.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A gravity-flotation collaborative recovery stage separation process for tin-bearing spodumene ore, comprising the following steps:

[0007] S1. Crush the raw ore, and then obtain three particle sizes of greater than 6 mm, 0.5 mm - 6 mm, and less than 0.5 mm through screening and classification;

[0008] S2. Return the ore with a particle size greater than 6 mm to step S1 for continuous crushing and screening; Feed the ore with a particle size of 0.5 mm - 6 mm into a heavy medium cyclone to obtain lithium concentrate 1, heavy medium middlings, and heavy medium tailings; Subject the ore with a particle size less than 0.5 mm to gravity separation to obtain tin concentrate 1 and gravity separation tailings 1;

[0009] S3. The heavy medium middlings obtained in step S2 and the gravity separation tailings 1 enter the grinding and classification system, are ground in a mill and then enter a hydrocyclone for classification, and the classified sand is returned to the grinding and classification system for continuous grinding and classification;

[0010] S4. Conduct flotation on the classified overflow obtained in step S3 to obtain lithium concentrate 2 and flotation tailings;

[0011] S5. Feed lithium concentrate 1 obtained in step S2 and lithium concentrate 2 obtained in step S4 into a smelting system to obtain lithium products and smelting slag, and conduct gravity separation on the smelting slag to obtain tin concentrate 2 and gravity separation tailings 2.

[0012] Further, in step S2, the feed pressure of the heavy medium cyclone is 0.15 MPa, and the inclination angle is 15°; The heavy medium material is ferrosilicon powder, and its density is 6.7 - 7.1 g / cm 3 , and its particle size is such that -0.045 mm accounts for 85 - 90%.

[0013] Further, in step S2, the ore with a particle size of 0.5 mm - 6 mm is processed by a two-stage heavy medium cyclone; Lithium concentrate 1 and the first-stage tailings are obtained in the treatment of the first-stage heavy medium cyclone, and the first-stage tailings enter the treatment of the second-stage heavy medium cyclone to obtain heavy medium middlings and heavy medium tailings.

[0014] Further, in step S2, the ore with a particle size less than 0.5 mm enters a sluice table for gravity separation operation.

[0015] Further, in step S3, calculated by dry weight per ton of raw ore, 700 g / t of sodium carbonate is added to the mill; The fineness of the classified overflow is such that -0.075 mm accounts for 65%.

[0016] Further, in step S4, the specific process of the flotation is as follows:

[0017] S4.1. Adjust the pulp mass concentration to 30% and then carry out the roughing operation; based on the dry weight of the ore entering the flotation, first add 150 g / t of sodium hydroxide to the pulp, stir for 15 minutes, then add 150 g / t of magnesium chloride, stir for 5 minutes, then add 1500 g / t of collector, stir for 3 minutes, and then inflate and skim the foam to obtain the roughing concentrate and the roughing tailings; the roughing concentrate enters step S4.4, and the roughing tailings enter step S4.2;

[0018] S4.2. First scavenging operation: based on the dry weight of the ore entering the flotation, add 70 g / t of magnesium chloride to the roughing tailings, stir for 5 minutes, then add 300 g / t of collector, stir for 3 minutes, and then inflate and skim the foam. The first scavenging concentrate obtained is returned to the roughing operation, and the first scavenging tailings obtained enter the second scavenging operation;

[0019] S4.3. Second scavenging operation: based on the dry weight of the ore entering the flotation, first add 35 g / t of magnesium chloride to the first scavenging tailings and stir for 5 minutes, then add 150 g / t of collector and stir for 3 minutes. After inflating and skimming the foam, the second scavenging concentrate obtained is returned to the first scavenging operation, and the second scavenging tailings obtained are added to the tailings pond;

[0020] S4.4. First cleaning operation: based on the dry weight of the ore entering the flotation, add 400 g / t of sodium carbonate to the roughing concentrate and stir for 5 minutes, and then inflate and skim the foam. The first cleaning concentrate obtained enters the second cleaning operation, and the first cleaning tailings obtained are returned to the roughing operation;

[0021] S4.5. Second cleaning operation: based on the dry weight of the ore entering the flotation, add 200 g / t of sodium carbonate to the first cleaning concentrate and stir for 5 minutes, and then inflate and skim the foam. The second cleaning concentrate obtained enters the third cleaning operation, and the second cleaning tailings obtained are returned to the first cleaning operation;

[0022] S4.6. Third cleaning operation: based on the dry weight of the ore entering the flotation, add 100 g / t of sodium carbonate to the second cleaning concentrate and stir for 5 minutes, and then inflate and skim the foam to obtain lithium concentrate 2. The third cleaning tailings obtained are returned to the second cleaning operation.

[0023] Furthermore, the collector used in steps S4.1, S4.2 and S4.3 is fatty oxime acid.

[0024] Furthermore, in step S5, lithium concentrate 1 and lithium concentrate 2 in the smelting system are subjected to transformation roasting and sulfation roasting, and then the roasted ore is subjected to water leaching for lithium extraction. After the water leaching is completed, liquid-solid separation is carried out to obtain the tin-containing smelting slag and the lithium-containing leaching solution. The lithium-containing leaching solution is recovered for lithium to obtain lithium products.

[0025] Even further, in step S5, the smelting slag enters a shaking table for gravity separation operation, and the shaking table is a slime shaking table.

[0026] The beneficial effects of the present invention are as follows:

[0027] (1) For the tin-bearing spodumene ore, the present invention adopts a beneficiation method combining gravity separation and flotation to achieve staged separation, which is efficient, green, and makes full use of the ore properties such as the specific gravity, particle size, and dissemination relationship of the tin-bearing spodumene ore, avoiding the metal loss of lithium and tin caused by over-grinding. At the same time, the heavy medium beneficiation, gravity separation, and flotation processes realize the recovery of spodumene and associated cassiterite in coarse and fine particle sizes, enabling different particle size minerals to be recovered step by step under the optimal equipment environment and process parameters, and maximizing the recovery of valuable metal resources of tin and lithium.

[0028] (2) For the spodumene concentrate mainly composed of spodumene, during the roasting and leaching smelting processes of spodumene, mineral phase reconstruction occurs, and most metal cations are leached. However, due to the high melting and boiling points of cassiterite and its insolubility in water and dilute acid solutions, its physical and chemical properties are relatively stable, and mineral phase reconstruction basically does not occur during the smelting process, resulting in a further increase in the specific gravity difference between the two. In the traditional process, the smelting slag of spodumene concentrate is directly sent to the tailings pond, causing the associated metal tin not to be recovered and resulting in resource waste. The present invention creatively proposes to recover tin from the smelting slag by gravity separation, which can truly achieve the full recovery and utilization of resources.

[0029] (3) The present invention provides a staged separation process for comprehensively recovering tin and lithium from spodumene ore with high efficiency, greenness, and high resource utilization rate, which can provide reference for the recovery of this type of spodumene ore resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a process flow chart of Embodiment 1 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The present invention will be further described below with reference to the drawings. It should be noted that this embodiment is based on the present technical solution and gives detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to this embodiment.

[0032] Embodiment 1

[0033] The ore selected in this embodiment is a spodumene ore from a certain place in Africa. The original ore contains 1.46% Li2O and 0.06% Sn. The main useful minerals in the ore are spodumene and cassiterite, and the gangue minerals are quartz, feldspar, etc.

[0034] This embodiment provides a gravity-flotation collaborative recovery staged separation process for tin-bearing spodumene ore to process the above ore, as Figure 1 shown, including the following steps:

[0035] S1. Crush the raw ore using a high-pressure roller mill, and then obtain three particle sizes, namely greater than 6 mm (+6 mm), 0.5 mm - 6 mm (-6 mm + 0.5 mm), and less than 0.5 mm (-0.5 mm), through screening and classification.

[0036] S2. Return the coarse particle size ore greater than 6 mm to the high-pressure roller mill for continued crushing, screening, and classification; feed the ore with a particle size of 0.5 mm - 6 mm into a heavy medium cyclone. The feed pressure of the heavy medium cyclone is 0.15 MPa, the inclination angle is 15°, the heavy medium material is ferrosilicon powder, and its density is 6.7 g / cm 3 , and its particle size is such that -0.045 mm accounts for 85%. Lithium concentrate 1 and the first-stage tailings are obtained during the treatment of the first-stage heavy medium cyclone. The first-stage tailings enter the treatment of the second-stage heavy medium cyclone to obtain heavy medium middlings and heavy medium tailings. Feed the ore with a particle size less than 0.5 mm into a sluice table for gravity separation operation. After the gravity separation operation, tin concentrate 1 and gravity separation tailings 1 are obtained.

[0037] S3. Feed the heavy medium middlings and gravity separation tailings 1 obtained in step S2 into a grinding and classification system. First, perform grinding in a ball mill, and 700 g / t of sodium carbonate is added to the mill per ton of dry weight of the raw ore; after grinding in the ball mill, enter a hydrocyclone for classification. The classified sand is returned to the grinding and classification system for grinding and classification, and the classified overflow enters a stirring tank. The fineness of the classified overflow is such that -0.075 mm accounts for 65%.

[0038] S4. Perform flotation on the classified overflow obtained in step S3 to obtain lithium concentrate 2 and flotation tailings:

[0039] S4.1. Roughing operation: Adjust the pulp mass concentration to 30% and then perform the roughing operation. During the roughing operation, based on the dry weight of the ore entering the flotation, first add 150 g / t of sodium hydroxide to the pulp, stir for 15 minutes, then add 150 g / t of magnesium chloride, stir for 5 minutes, then add 1500 g / t of collector fatty acid oxime, stir for 3 minutes, and then inflate and skim the foam to obtain roughing concentrate and roughing tailings; the roughing concentrate enters step S4.4, and the roughing tailings enter step S4.2;

[0040] S4.2. First scavenging operation: Based on the dry weight of the ore entering the flotation, add 70 g / t of magnesium chloride to the roughing tailings, stir for 5 minutes, then add 300 g / t of collector fatty acid oxime, stir for 3 minutes, and then inflate and skim the foam. The first scavenging concentrate obtained is returned to the roughing operation, and the first scavenging tailings obtained enter the second scavenging operation;

[0041] S4.3. Second scavenging operation: Based on the dry weight of the ore entering the flotation process, first add 35 g / t of magnesium chloride to the tailings of the first scavenging operation and stir for 5 minutes, then add 150 g / t of the collector fatty acid hydroxamate and stir for 3 minutes. After aeration and skimming, the second scavenging concentrate obtained is returned to the first scavenging operation, and the second scavenging tailings obtained are added to the tailings pond;

[0042] S4.4. First cleaning operation: Based on the dry weight of the ore entering the flotation process, add 300 g / t of sodium carbonate to the rougher concentrate and stir for 5 minutes, then aerate and skim. The first cleaning concentrate obtained enters the second cleaning operation, and the first cleaning tailings obtained are returned to the rougher operation;

[0043] S4.5. Second cleaning operation: Based on the dry weight of the ore entering the flotation process, add 150 g / t of sodium carbonate to the first cleaning concentrate and stir for 5 minutes, then aerate and skim. The second cleaning concentrate obtained enters the third cleaning operation, and the second cleaning tailings obtained are returned to the first cleaning operation;

[0044] S4.6. Third cleaning operation: Add 50 g / t of sodium carbonate to the second cleaning concentrate and stir for 5 minutes, then aerate and skim to obtain lithium concentrate 2. The third cleaning tailings obtained are returned to the second cleaning operation.

[0045] S5. Feed lithium concentrate 1 obtained in step S2 and lithium concentrate 2 obtained in step S4 into the smelting system. After transformation roasting and sulfation roasting, the roasted ore is subjected to water leaching for lithium extraction. After the water leaching is completed, liquid-solid separation is carried out to obtain tin-containing smelting slag (yield 95%) and lithium-containing leachate. Recover lithium from the lithium-containing leachate to obtain lithium products. The smelting slag enters the slime shaking table for gravity separation to obtain tin concentrate 2 and gravity separation tailings 2.

[0046] It should be noted that the collector fatty acid hydroxamate used is the fatty acid hydroxamate disclosed in Chinese Patent Application CN119114293A.

[0047] Comparative Example 1

[0048] The ore processed in this comparative example is the same as that in Examples 1 and 2. The processing flow includes the following steps:

[0049] S1. Crush the raw ore using a high-pressure roller mill, and then obtain three particle sizes of greater than 6 mm, 0.5 mm - 6 mm, and less than 0.5 mm through screening and classification.

[0050] S2. Return the coarse particle size ore greater than 6 mm to the high-pressure roller mill for further crushing; feed the ore with a particle size of 0.5 mm - 6 mm into the heavy medium cyclone; the feed pressure of the heavy medium cyclone is 0.15 MPa, the inclination angle is 15°, the heavy medium material is ferrosilicon powder, and the density is 6.7 g / cm 3, the particle size of -0.045mm accounts for 85%. Lithium concentrate 1 and the first-stage tailings are obtained in the treatment of the first-stage heavy-medium cyclone. The first-stage tailings enter the treatment of the second-stage heavy-medium cyclone to obtain heavy-medium middlings and heavy-medium tailings.

[0051] S3. Grinding and classification operation: The heavy-medium middlings obtained in step S2 and the product with a particle size less than 0.5mm in step S1 are fed into the grinding and classification system. First, grinding is carried out in a ball mill, and after grinding in the ball mill, it enters a hydrocyclone for classification. The classified sand is returned to the grinding and classification system for grinding and classification, and the classified overflow enters a stirring tank. The fineness of the classified overflow is that -0.075mm accounts for 65%.

[0052] S4. Gravity separation operation: The classified overflow product obtained in step S3 enters the gravity separation operation, and after tabling gravity separation, tin concentrate and gravity separation tailings are obtained;

[0053] S5. Floatation is carried out on the gravity separation tailings obtained in step S4:

[0054] S5.1. Rougher operation: After adjusting the pulp mass concentration to 30%, the rougher operation is carried out. In the rougher operation, calculated by the dry weight of the ore volume entering the flotation, first add 150g / t of sodium hydroxide to the pulp, stir for 15 minutes, then add 150g / t of magnesium chloride, stir for 5 minutes, then add 1500g / t of the collector fatty acid hydroxamate, stir for 3 minutes, and then inflate and foam to obtain rougher concentrate and rougher tailings; The rougher concentrate enters step S5.4, and the rougher tailings enter step S5.2;

[0055] S5.2. First scavenging operation: The rougher tailings obtained in step S5.1 are subjected to the first scavenging operation; In the first scavenging operation, add 70g / t of magnesium chloride to the rougher tailings, stir for 5 minutes, then add 300g / t of the collector fatty acid hydroxamate, stir for 3 minutes, and then inflate and foam. The first scavenging concentrate obtained is returned to the rougher operation, and the first scavenging tailings obtained enter the second scavenging operation;

[0056] S5.3. Second scavenging operation: In the second scavenging operation, first add 35g / t of magnesium chloride to the first scavenging tailings and stir for 5 minutes, then add 150g / t of the collector fatty acid hydroxamate and stir for 3 minutes. After inflating and foaming, the second scavenging concentrate obtained is returned to the first scavenging operation, and the second scavenging tailings obtained are added to the tailings pond;

[0057] S5.4. First cleaning operation: The rougher concentrate obtained in step S4.1 enters the first cleaning operation; In the first cleaning operation, add 300g / t of sodium carbonate to the rougher concentrate and stir for 5 minutes, and then inflate and foam. The first cleaning concentrate obtained enters the second cleaning operation, and the first cleaning tailings obtained are returned to the rougher operation;

[0058] S5.5, Second concentration operation: In the second concentration operation, 150 g / t of sodium carbonate is added to the concentrate from the first concentration, and after stirring for 5 minutes, air is introduced for foaming. The concentrate obtained from the second concentration enters the third concentration operation, and the tailings obtained from the second concentration are returned to the first concentration operation;

[0059] S5.6, Third concentration operation: In the third concentration operation, 50 g / t of sodium carbonate is added to the concentrate from the second concentration, and after stirring for 5 minutes, air is introduced for foaming to obtain lithium concentrate 2. The tailings obtained from the third concentration are returned to the second concentration operation.

[0060] S6. Feed lithium concentrate 1 obtained in step S2 and lithium concentrate 2 obtained in step S5 into the smelting system. After transformation roasting and sulfation roasting, the roasted ore is subjected to water leaching for lithium extraction. After the water leaching is completed, liquid-solid separation is carried out to obtain tin-containing smelting slag and lithium-containing leaching solution. The lithium in the lithium-containing leaching solution is recovered to obtain lithium products.

[0061] The process indexes of Example 1 and Comparative Example 1 are shown in Table 1.

[0062] Table 1

[0063]

[0064]

[0065] As can be seen from Table 1, in Example 1, the grade of tin concentrate can reach 45.84%, the comprehensive recovery rate of tin beneficiation is 65.38%, the grade of spodumene concentrate is 6.00%, and the comprehensive recovery rate of lithium beneficiation is 86.98%. In Comparative Example 1, the grade of tin concentrate is 46.96%, the comprehensive recovery rate of tin beneficiation is 34.41%, the grade of spodumene concentrate is 6.00%, and the comprehensive recovery rate of lithium beneficiation is 87.09%.

[0066] Compared with Comparative Example 1, in the method of Example 1, when the comprehensive recovery rate of lithium beneficiation only decreases by about 0.11%, the comprehensive recovery rate of tin beneficiation increases by about 31%, and the grade of tin concentrate meets the requirements of the same grade. Therefore, Example 1 greatly improves the economic benefits of the minerals.

[0067] The method of Example 1 utilizes the ore property characteristics of pegmatite-type minerals. Generally, the spodumene is closely disseminated with cassiterite, and the dissemination size of spodumene is relatively coarse. Ore with a particle size of 0.5 mm - 6 mm is fed into the heavy medium separation to obtain spodumene concentrate, and the cassiterite closely disseminated with spodumene is enriched in the spodumene concentrate 1 during the heavy medium separation operation. Ore with a particle size less than 0.5 mm is first fed into the gravity separation system to recover some of the already dissociated cassiterite. Then, the middlings from the heavy medium separation and the gravity separation tailings 1 are ground and classified and then fed into the flotation operation. Under the action of the collector, lithium and tin are enriched into the spodumene concentrate 2. In the method of Comparative Example 1, ore with a particle size less than 0.5 mm is directly fed into the flotation operation, ignoring the dissociation of cassiterite in the particle size range less than 0.5 mm. However, the content of the particle size range of -0.355 + 0.025 mm in the particle size range less than 0.5 mm accounts for more than 80%, which fully meets certain gravity separation conditions. This is an important reason for the relatively low comprehensive recovery rate of tin ore dressing in Comparative Example 1.

[0068] For those skilled in the art, various corresponding changes and deformations can be given according to the above technical solutions and concepts, and all such changes and deformations should be included within the protection scope of the claims of the present invention.

Claims

1. A gravity-floatation collaborative recovery stage separation process for spodumene ore containing tin, characterized in that, It includes the following steps: S1. Crush the raw ore, and then obtain three particle sizes of greater than 6 mm, 0.5 mm - 6 mm, and less than 0.5 mm through screening and classification; S2. Return the ore with a particle size greater than 6 mm to step S1 for continuous crushing and screening; Feed the ore with a particle size of 0.5 mm - 6 mm into a heavy medium cyclone to obtain lithium concentrate 1, heavy medium middlings, and heavy medium tailings; Perform gravity separation on the ore with a particle size less than 0.5 mm to obtain tin concentrate 1 and gravity separation tailings 1; S3. The heavy medium middlings and gravity separation tailings 1 obtained in step S2 enter the grinding and classification system, are ground in a mill and then enter a hydrocyclone for classification, and the classified sand is returned to the grinding and classification system for continuous grinding and classification; S4. Perform flotation on the classified overflow obtained in step S3 to obtain lithium concentrate 2 and flotation tailings; S5. Feed lithium concentrate 1 obtained in step S2 and lithium concentrate 2 obtained in step S4 into a smelting system to obtain lithium products and smelting slag, and the smelting slag is subjected to gravity separation to obtain tin concentrate 2 and gravity separation tailings 2.

2. The process according to claim 1, characterized in that, In step S2, the feed pressure of the heavy medium cyclone is 0.15 MPa and the inclination angle is 15°; the heavy medium material is ferrosilicon powder with a density of 6.7 - 7.1 g / cm 3 , and the particle size of -0.045 mm accounts for 85 - 90%.

3. The process according to claim 1, characterized in that, In step S2, the ore with a particle size of 0.5 mm - 6 mm is processed by a two-stage heavy medium cyclone; Lithium concentrate 1 and the first-stage tailings are obtained in the processing of the first-stage heavy medium cyclone, and the first-stage tailings enter the processing of the second-stage heavy medium cyclone to obtain heavy medium middlings and heavy medium tailings.

4. The process according to claim 1, characterized in that, In step S2, the ore with a particle size less than 0.5 mm enters a sluice table for gravity separation operation.

5. The process according to claim 1, characterized in that, In step S3, calculated by the dry weight of each ton of raw ore, 700 g / t of sodium carbonate is added to the mill; The fineness of the classified overflow is 65% of -0.075 mm.

6. The process according to claim 1, characterized in that, In step S4, the specific process of the flotation is as follows: S4.

1. Adjust the pulp mass concentration to 30% and then perform roughing operation; Calculated by the dry weight of the ore entering the flotation, first add 150 g / t of sodium hydroxide to the pulp, stir for 15 minutes, then add 150 g / t of magnesium chloride, stir for 5 minutes, then add 1500 g / t of collector, stir for 3 minutes, and then inflate and scrape foam to obtain roughing concentrate and roughing tailings; The roughing concentrate enters step S4.4, and the roughing tailings enter step S4.2; S4.

2. First scavenging operation: Calculated by the dry weight of the ore entering the flotation, add 70 g / t of magnesium chloride to the roughing tailings, stir for 5 minutes, then add 300 g / t of collector, stir for 3 minutes, and then inflate and scrape foam. The first scavenging concentrate obtained is returned to the roughing operation, and the first scavenging tailings obtained enter the second scavenging operation; S4.

3. Second scavenging operation: Calculated by the dry weight of the ore entering the flotation, first add 35 g / t of magnesium chloride to the first scavenging tailings and stir for 5 minutes, then add 150 g / t of collector and stir for 3 minutes, inflate and scrape foam, and the second scavenging concentrate obtained is returned to the first scavenging operation, and the second scavenging tailings obtained are added to the tailings pond; S4.

4. First cleaning operation: Calculated by the dry weight of the ore entering the flotation, add 400 g / t of sodium carbonate to the roughing concentrate and stir for 5 minutes, then inflate and scrape foam. The first cleaning concentrate obtained enters the second cleaning operation, and the first cleaning tailings are returned to the roughing operation; S4.5, Second-stage cleaning operation: Based on the dry weight of the ore fed into the flotation process, add 200 g / t of sodium carbonate to the concentrate from the first-stage cleaning, stir for 5 minutes, then aerate and skim the foam. The concentrate obtained from the second-stage cleaning enters the third-stage cleaning operation, and the tailings from the second-stage cleaning are returned to the first-stage cleaning operation; S4.6, Third-stage cleaning operation: Based on the dry weight of the ore fed into the flotation process, add 100 g / t of sodium carbonate to the concentrate from the second-stage cleaning, stir for 5 minutes, then aerate and skim the foam to obtain lithium concentrate 2. The tailings from the third-stage cleaning are returned to the second-stage cleaning operation.

7. The process according to claim 6, characterized in that, The collector used in steps S4.1, S4.2 and S4.3 is fatty oxime acid.

8. The process according to claim 1, characterized in that, In step S5, lithium concentrate 1 and lithium concentrate 2 are in the smelting system. After transformation roasting and sulfation roasting, the roasted ore is subjected to water leaching for lithium extraction. After the water leaching is completed, liquid-solid separation is carried out to obtain tin-containing smelting slag and lithium-containing leachate. The lithium in the lithium-containing leachate is recovered to obtain lithium products.

9. The process according to claim 1 or 8, characterized in that, In step S5, the smelting slag enters a shaking table for gravity separation operation, and the shaking table is a slime shaking table.

Images