Method for upgrading bauxite and efficiently enriching lithium
By employing a grinding-classification-gravity separation-flotation process, the problem of low aluminum-lithium separation efficiency in low-grade bauxite has been solved, achieving efficient synergistic recovery and enrichment of aluminum and lithium, improving the quality of aluminum concentrate and lithium recovery rate, and reducing beneficiation costs.
Patent Information
- Application Number
- CN202511496863.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-20
- Publication Date
- 2026-01-23
AI Technical Summary
Existing technologies are insufficient for efficiently separating and enriching aluminum and lithium in low-grade bauxite, resulting in high beneficiation costs, low efficiency, and unsatisfactory lithium recovery rates and aluminum-silicon ratios.
The process flow of grinding-classification-gravity separation-flotation is adopted. Bauxite is divided into coarse and fine particles through grinding, and then processed by gravity separation and flotation respectively. The flotation process is optimized by combining pH adjuster, inhibitor and collector to achieve synergistic recovery of aluminum and lithium.
It improved the quality and yield of aluminum concentrate, reduced the amount of material fed into flotation and the consumption of collectors, achieved efficient aluminum-lithium separation, and achieved an aluminum-silicon ratio of about 10, thereby reducing beneficiation costs and enhancing the economic value of the ore.
Smart Images
Figure CN121372647A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mineral processing technology, and in particular to a method for upgrading bauxite and synergistically enriching lithium efficiently. Background Technology
[0002] Currently, bauxite mining generally requires an aluminum-silicon ratio (ASR) greater than 2.5, while the Bayer high-pressure leaching process requires an ASR higher than 4.5. A large amount of low- and medium-grade bauxite in mining areas is used only in small quantities for blending due to a lack of economically effective upgrading technologies; the majority is either stockpiled as mining waste or left unmined. Therefore, developing technically feasible and economically sound key technologies for upgrading low- and medium-grade bauxite, and effectively revitalizing this resource, is of significant strategic importance for alleviating the shortage of bauxite resources in my country and enhancing its resource self-sufficiency.
[0003] It is worth noting that low- to medium-grade bauxite often contains high levels of lithium. In some areas, the lithium content in bauxite has reached industrial grade (Li₂O 0.1%–0.5%), demonstrating significant potential for comprehensive utilization.
[0004] In desilication and upgrading, flotation is currently the main method used. However, due to the fine particle size of gibbsite in bauxite, the grinding fineness during beneficiation usually needs to reach over 90% -0.074 mm. Although this process helps to fully liberate the valuable minerals, the excessively fine particle size of the feed material significantly reduces the selectivity of the separation process and makes dewatering of the beneficiated products difficult.
[0005] Lithium in bauxite is primarily found in clay minerals. Clay minerals are less hard than gibbsite and are preferentially ground during grinding, resulting in lithium enrichment in the finer particles and aluminum enrichment in the coarser particles. Direct flotation can initially separate and enrich aluminum and lithium; however, clay minerals are prone to mud formation during grinding, severely impacting flotation separation efficiency and consequently reducing the quality of the aluminum concentrate and the efficiency of aluminum-lithium separation. Therefore, there is an urgent need to develop novel and efficient aluminum-lithium separation and enrichment technologies to achieve the synergistic recovery and efficient utilization of aluminum and lithium. Summary of the Invention
[0006] This invention proposes a method for bauxite upgrading and synergistic lithium enrichment, which not only improves the quality of bauxite concentrate, but also reduces the amount of flotation feed and collector consumption by more than 30%, while achieving efficient lithium enrichment and a high aluminum-silicon ratio of around 10.
[0007] The technical solution of this invention is implemented as follows: A method for bauxite upgrading and synergistic lithium enrichment includes the following steps: (1) The lithium-bearing bauxite is ground and classified to obtain coarse-grained minerals and fine-grained minerals; (2) the coarse-grained minerals are subjected to gravity separation to obtain gravity separation concentrate and gravity separation tailings, and the gravity separation tailings and the fine-grained minerals are combined to perform a flotation operation to obtain flotation concentrate and flotation tailings; (3) the flotation tailings are lithium-rich products, and the flotation concentrate and the gravity separation concentrate are combined to obtain aluminum concentrate.
[0008] Further, in step (1), the Li2O grade of the lithium-bearing bauxite is 0.1% to 0.6%, the Al2O3 grade is > 50%, and the aluminum-silicon ratio is > 1.8.
[0009] Further, in step (1), the grinding fineness is 80% to 95% of -0.074 mm.
[0010] Further, in step (1), the classification particle size is 20 μm to 100 μm, and the classification method can be gravity field, centrifugal force field or screening, etc.
[0011] Further, in step (2), the flotation operation adopts bauxite direct flotation method, including once roughing, twice roughing and once cleaning, the tailings of the once roughing are subjected to the twice roughing to obtain roughing tailings, the concentrate of the once roughing and the concentrate of the twice roughing are combined to perform the once cleaning to obtain the flotation concentrate and cleaning tailings, and the cleaning tailings and the roughing tailings are combined to obtain the flotation tailings.
[0012] Further, the once roughing uses 500-1000 g / t of pH adjuster, 10-30 g / t of depressant and 200-400 g / t of collector; The twice roughing uses 100-200 g / t of collector; The once cleaning uses 100-200 g / t of pH adjuster, 10-20 g / t of depressant and 80-100 g / t of collector.
[0013] Further, the pH adjuster is sodium carbonate, the depressant is sodium hexametaphosphate, and the collector is one or more of oleic acid, oxidized paraffin soap, petroleum sulfonate sodium or hydroxamic acid.
[0014] Further, the gravity separation adopts one of a shaking table, a spiral chute and a centrifugal concentrator.
[0015] The beneficial effects of the present application are as follows: The present application reduces the influence of fine particles on aluminum recovery by adopting grinding-classification-coarse and fine separation, which is beneficial to obtaining high-quality aluminum concentrate, and can reduce the flotation amount and collector consumption by more than 30%; on this basis, the optimization of the flotation operation ensures efficient recovery of aluminum, realizes an aluminum-silicon ratio of about 10, and simultaneously realizes efficient enrichment of lithium. The process reduces the beneficiation cost while improving the economic value of the ore. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.
[0017] Figure 1 Process flow diagram of the method for upgrading bauxite and synergistically efficiently enriching lithium; Figure 2 Picture of the gravity concentration concentrate of Example 1; Figure 3 Picture of the aluminum concentrate of Comparative Example 1. DETAILED DESCRIPTION
[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only constitute some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0019] Example 1 A lithium-containing bauxite, with Al2O3 content of 57.67%, SiO2 content of 11.73%, Li2O content of 0.15%, and main mineral composition of diaspore, kaolinite, illite, etc.
[0020] A method for upgrading bauxite and synergistically efficiently enriching lithium, comprising the following steps: (1) grinding the lithium-containing bauxite ore into a rod mill for grinding, with grinding fineness of -0.074 mm accounting for 88%; (2) classifying the ground ore by screening classification method, with classification particle size of 74 μm, to obtain coarse-grained minerals and fine-grained minerals; (3) gravity concentrating the classified coarse-grained minerals by a shaking table to obtain gravity concentration concentrate and gravity concentration tailings, and the picture of the gravity concentration concentrate is as shown in Figure 2 (4) the heavy selection tailings and the classified fine particle grade minerals are combined and put into a flotation tank, and flotation is carried out by adding a pH regulator, an inhibitor and a collector, and the flotation process adopts "two rough selections and one selection", the pH regulator of rough selection 1 is sodium carbonate, the dosage is 500 g / t, the inhibitor is sodium hexametaphosphate, the dosage is 30 g / t, the collector is oleic acid and benzenecarbohydroxamic acid (10:1), and the dosage is 400 g / t; the dosage of the collector of rough selection 2 is 150 g / t; the dosage of sodium carbonate of selection is 100 g / t, the dosage of sodium hexametaphosphate is 15 g / t, and the dosage of the collector is 80 g / t, the tailings of selection and the tailings of rough selection are combined to be a lithium-rich product, and the flotation concentrate and the heavy selection concentrate are combined to be an aluminum concentrate.
[0021] According to the beneficiation process steps of the present application, the lithium-containing bauxite is comprehensively recovered, and the results obtained in the embodiment are as follows: the yield of the aluminum concentrate is 67.32%, the Al2O3 grade is 62.21%, the recovery rate is 72.62%, and the A / S is 9.77; the yield of the lithium-rich product is 32.68%, the Li2O grade is 0.28%, the recovery rate is 63.45%, and the enrichment ratio of lithium is 1.87.
[0022] Example 2 A certain lithium-containing bauxite, the content of Al2O3 is 52.89%, the content of SiO2 is 17.51%, the content of Li2O is 0.28%, and the main mineral components are diaspore, kaolinite and illite.
[0023] A method for upgrading bauxite and synergistically efficiently enriching lithium, comprising the following steps: (1) the lithium-containing bauxite ore is ground in a rod mill, and the grinding fineness is 90% of -0.074 mm; (2) the ground ore is classified by screening, and the classification particle size is 74 μm; (3) the classified coarse particles are subjected to gravity separation by a shaking table to obtain a shaking table concentrate and tailings; (4) the tailings of the shaking table and the classified fine particles are combined and put into a flotation tank, and flotation is carried out by adding a pH regulator, an inhibitor and a collector, and the flotation process adopts "two rough selections and one selection", the pH regulator of rough selection 1 is sodium carbonate, the dosage is 800 g / t, the inhibitor is sodium hexametaphosphate, the dosage is 30 g / t, the collector is oleic acid and petroleum sodium sulfonate (2:1), and the dosage is 300 g / t; the dosage of the collector of rough selection 2 is 100 g / t; the dosage of sodium carbonate of selection is 200 g / t, the dosage of sodium hexametaphosphate is 20 g / t, and the dosage of the collector is 80 g / t, the tailings of selection and the tailings of rough selection are combined to be a lithium-rich product, and the flotation concentrate and the shaking table concentrate are combined to be an aluminum concentrate.
[0024] The comprehensive recovery of the lithium-containing bauxite according to the beneficiation process step of the present application obtains the results that the yield of the aluminum concentrate is 63.28%, the grade of Al2O3 is 60.56%, the recovery rate is 72.45%, and the A / S is 10.33; the yield of the lithium-rich product is 36.72%, the grade of Li2O is 0.58%, the recovery rate is 75.37%, and the enrichment ratio of lithium is 2.07.
[0025] Comparative Example 1 The raw material treated in Comparative Example 1 and Example 2 is the same, and the difference is that the full flotation process is used in the comparative example, the raw ore is directly ground to a fineness of 90% of -0.074 mm, and then the flotation reagents are added to directly perform the flotation, the flotation process adopts "two roughing and two cleaning", the pH adjusting agent for roughing 1 is sodium carbonate, the dosage is 3500 g / t, the depressant is sodium hexametaphosphate, the dosage is 60 g / t, and the collector is oleic acid, the dosage is 500 g / t; the dosage of the collector for roughing 2 is 200 g / t; the dosage of sodium carbonate for cleaning 1 is 300 g / t, the dosage of sodium hexametaphosphate is 40 g / t, and the dosage of the collector is 100 g / t; the dosage of the collector for cleaning 2 is 50 g / t, the cleaning tailings, the roughing tailings and the fine particle level are combined as the lithium-rich product, and the flotation concentrate is the aluminum concentrate, and the picture of the aluminum concentrate is shown in Figure 3 .
[0026] The results obtained in the present comparative example are that the yield of the aluminum concentrate is 62.37%, the grade of Al2O3 is 59.35%, the recovery rate is 70.09%, and the A / S is 8.32; the yield of the lithium-rich product is 37.63%, the grade of Li2O is 0.52%, the recovery rate is 70.70%, and the enrichment ratio of lithium is 1.86.
[0027] In the present comparative example, the grade, the recovery rate and the aluminum-silicon ratio of the aluminum concentrate are all lower than those of Example 2, the grade and the recovery rate of the lithium-rich product are all lower than those of Example 2, and the flotation process of Example 2 is shorter and the reagent consumption is lower.
[0028] The above only describes the preferred embodiments of the present application and should not be used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims
1. A method for synergistically upgrading bauxite and efficiently enriching lithium, characterized in that, The method comprises the following steps: (1) grinding and classifying the lithium-bearing bauxite to obtain coarse-grained minerals and fine-grained minerals; (2) performing gravity separation on the coarse-grained minerals to obtain gravity separation concentrates and gravity separation tailings, and combining the gravity separation tailings and the fine-grained minerals to perform flotation operation to obtain flotation concentrates and flotation tailings; (3) the flotation tailings are lithium-rich products, and the flotation concentrates and the gravity separation concentrates are combined to obtain aluminum concentrates; Further, in step (1), the lithium-bearing bauxite has a Li2O grade of 0.1% to 0.6%, an Al2O3 grade of more than 50%, and an aluminum-silicon ratio of more than 1.
8.
2. The method for synergistically enriching lithium with bauxite upgrading according to claim 1, characterized in that, In step (1), the grinding fineness is 80% to 95% of -0.074 mm.
3. The method for synergistically enriching lithium with bauxite upgrading according to claim 1, characterized in that, In step (1), the classification particle size is 20 μm to 100 μm.
4. The method for synergistically enriching lithium with bauxite upgrading according to claim 1, characterized in that, In step (2), the flotation operation adopts a bauxite direct flotation method, which comprises primary roughing, secondary roughing, and primary cleaning, the tailings of the primary roughing are subjected to the secondary roughing to obtain roughing tailings, the concentrates of the primary roughing and the secondary roughing are combined to perform the primary cleaning to obtain the flotation concentrates and cleaning tailings, and the cleaning tailings and the roughing tailings are combined to obtain the flotation tailings.
5. The method for synergistically enriching lithium with bauxite upgrading according to claim 4, characterized in that, The dosage of the pH adjuster for the primary roughing is 500-1000 g / t, the dosage of the depressant is 10-30 g / t, and the dosage of the collector is 200-400 g / t; The dosage of the collector for the secondary roughing is 100-200 g / t; The dosage of the pH adjuster for the primary cleaning is 100-200 g / t, the dosage of the depressant is 10-20 g / t, and the dosage of the collector is 80-100 g / t.
6. The method for synergistically enriching lithium with bauxite upgrading according to claim 5, characterized in that, The pH adjuster is sodium carbonate, the depressant is sodium hexametaphosphate, and the collector is one or more of oleic acid, oxidized paraffin soap, petroleum sulfonate sodium, or hydroxamic acid.