Beneficiation method for enriching vanadium by combining gravity and flotation of high-calcium vanadium-containing shale

Abstract

The invention discloses a high-calcium vanadium-containing shale gravity-flotation combined vanadium enrichment beneficiation method. Raw ore is subjected to one-rough-one-fine reverse flotation to obtain concentrate and tailings; and the tailings are subjected to gravity separation through a spiral chute, low-calcium products in the coarse fraction and high-calcium products in the fine fraction are obtained, the low-calcium products in the coarse fraction are subjected to decalcification flotation, and obtained decalcified concentrate returns to raw ore to form a closed cycle. By adopting the method, the calcium oxide component in the high-calcium vanadium-containing shale is removed, and the grade of the vanadium raw material is effectively improved under the condition that the recovery rate of vanadium pentoxide is at a relatively high level, so that the acid consumption of decalcification in the vanadium extraction process is reduced. And the yield of the vanadium concentrate after mineral separation is about 50%, so that the smelting investment can be reduced by compressing the treatment capacity of smelting materials, and the purpose of reducing the production cost of a unit product is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of vanadium ore dressing, and in particular to a method for dressing high-calcium vanadium-containing shale by refloating and jointly enriching vanadium. Background Art

[0002] High-calcium vanadium-containing shale is widely distributed in my country and has huge reserves. However, due to the high calcium oxide content and the richness of muscovite and other mica minerals, the vanadium extraction process is complex and difficult. The main methods currently used include roasting-leaching, flotation, chemical methods and other processes; the roasting-leaching method pre-decarbonizes through the roasting process, reduces the consumption of acid by impurities in the acid leaching process, and improves the efficiency of vanadium compounds reacting with hydrogen ions to form soluble vanadates. The vanadium leaching rate is high, but high-calcium vanadium-containing shale contains a large amount of calcium-containing minerals such as dolomite and calcite, which are very easy to react with acid during the leaching process, consuming a large amount of acid and affecting the leaching efficiency. In order to solve the problem that the enrichment of vanadium in high-calcium vanadium-containing shale is difficult, costly and has certain pollution, it is more appropriate to use mineral processing to decalcify and enrich vanadium resources.

[0003] CN104959212A discloses a classification beneficiation method for mixed calcareous and siliceous stone coal vanadium ore, which can efficiently enrich vanadium ore and reduce the amount of pulp pH adjuster and inhibitor through coarse grinding and positive flotation process, thereby effectively reducing the beneficiation production cost. However, the process is too long and the recovery rate of vanadium is low, resulting in a waste of available resources.

[0004] CN104060108A discloses a classification and beneficiation method for mixed calcareous and siliceous stone coal vanadium ore. The method achieves good results through cyclone classification and a process of first removing calcium and then selecting vanadium. However, the single flotation method of vanadium enriches vanadium and separates vanadium and calcium. Due to the fine ore particle size, the flotation effect is poor, the number of vanadium selection sweeps is too many, and the process is complicated.

[0005] In summary, although the existing vanadium ore flotation process can solve the problem of vanadium resource enrichment to a certain extent, when leaching vanadium from the concentrate, due to the presence of dolomite, a large amount of alkali or acid will inevitably be consumed, which is not conducive to industrial production. Summary of the invention

[0006] The present invention provides a high-calcium vanadium-containing shale refloatation combined with vanadium enrichment beneficiation method, which can effectively remove a large amount of gangue minerals, increase the vanadium content in the concentrate, and realize the efficient separation of vanadium ore.

[0007] The technical solution of the present invention is to provide a vanadium beneficiation method for high-calcium vanadium-containing shale refloatation combined with vanadium enrichment, comprising the following steps: S1, the raw ore is subjected to a coarse and fine reverse flotation to obtain concentrate and tailings; S2. The tailings are re-selected using a spiral chute to obtain a coarse-grained low-calcium product and a fine-grained high-calcium product. The coarse-grained low-calcium product is decalcified and floated, and the decalcified concentrate is returned to the original ore in S1 to form a closed loop.

[0008] Optionally, in the high-calcium vanadium-containing shale ore, V 2 O 5 The grade is 0.80%-1.20%, and the CaO content is 8.00%-12.00%. The raw ore is ground, slurried and the pH is adjusted to alkaline before a coarse and fine reverse flotation operation.

[0009] Optionally, when grinding and slurrying the raw ore in S1, the percentage of mineral particles with a fineness of -0.074 mm is controlled to be 60-70%, and the slurry concentration is 20-30%; and the pH is adjusted to 9.5-10.5.

[0010] Optionally, decalcified collector and depressant are added to the raw ore in S1 for rough and fine reverse flotation; in the roughing, the amount of decalcified collector added is 1.0 kg / t-1.1 kg / t, and the amount of depressant added is 1.2kg / t-1.4 kg / t; in the fine separation, the amount of decalcified collector added is 0.4 kg / t-0.5 kg / t, and the amount of depressant added is 1.0kg / t-1.2kg / t.

[0011] Optionally, the tailings collected in S2 are first thickened by adding a flocculant and then enter a spiral chute for gravity separation.

[0012] Optionally, the flocculant for the thickening treatment is polyacrylamide, and the dosage is 1.0 kg / t -1.2 kg / t.

[0013] Optionally, at least one of the following conditions is met during reselection in S2: the spiral chute has a diameter ratio of 0.5-0.8; the chute diameter is 0.8-1.2 meters; the ratio of the interception points from the inside to the outside to the chute length is (3~4): (6~7).

[0014] Optionally, during decalcification flotation, a decalcification collector and a depressant are added; the amounts of the depressant and the decalcification collector are 0.2 kg / t -0.5 kg / t and 0.4 kg / t -0.5 kg / t, respectively.

[0015] Optionally, the inhibitor is a mixture of aluminum sulfate and water glass with a modulus of 2.0-3.0 in a ratio of 1:1-1.5.

[0016] Optionally, the decalcification collector is composed of sodium oleate, coconut amine and sodium lauryl sulfate, wherein sodium oleate accounts for 70-75wt%, coconut amine accounts for 10-15wt%, and sodium lauryl sulfate accounts for 10-20wt%.

[0017] The present invention has the following beneficial effects: The present invention provides a ore dressing method for high-calcium vanadium-containing shale re-floating and enriching vanadium. When the vanadium ore is crushed and screened, the calcium grade under the -300 mesh sieve has a significant upward trend. It is found through experiments that the lowest grade part is mainly dolomite. Dolomite is easy to grind, and the dissociation degree of the ground dolomite monomer is high. Most of them are fine-grained particles. It is more appropriate to separate them by re-selection. However, since a small part of vanadium resources exists in clay minerals with a high dissociation degree, directly using the re-selection method will cause a waste of part of the vanadium resources. Therefore, the present invention adopts a combination of re-selection and flotation to perform ore dressing.

[0018] The present invention carries out gravity separation and classification on the flotation tailings, and effectively separates the vanadium-containing minerals from the gangue minerals, wherein the gravity separation concentrate is a coarse-grained low-calcium product, which is a vanadium-containing mineral, and after a stage of reverse flotation, the concentrate is returned to the original ore for circulation; the gravity separation tailings are a fine-grained high-calcium product, which is a gangue mineral, and the removal of this part of the material significantly reduces the amount of reagents used in the tailings scavenging stage, saves the cost of flotation reagents, and simplifies the process flow.

[0019] The present invention realizes the enrichment and recovery of vanadium metal. The vanadium concentrate can be used as a raw material for smelting and extracting vanadium. The calcium oxide component in the high-calcium vanadium-containing shale can be removed, and the grade of the vanadium raw material can be effectively improved under the condition that the recovery rate of vanadium pentoxide is at a high level, thereby reducing the acid consumption of decalcification in the vanadium extraction process. The V content in the obtained vanadium concentrate is 2 O 5 Grade ≥1.7%, CaO grade ≤3.8% V 2 O 5 The recovery rate is ≥92%. The present invention also reduces the processing volume of smelting materials and reduces smelting investment, thereby achieving the purpose of reducing the production cost of unit products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Attached Figure 1 The invention provides a process flow chart of a mineral processing method. DETAILED DESCRIPTION

[0021] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0022] The experimental methods in the following examples are conventional methods unless otherwise specified. The raw materials, reagents, etc. used in the following examples are commercially available products unless otherwise specified.

[0023] Example 1 A method for ore dressing by refloating and enriching vanadium in high-calcium vanadium-containing shale In the high-calcium vanadium-containing shale sample of this example, V2 O 5 The grade is 1.02%, the CaO content is 10.08%, and the grinding and slurry adjustment operation is first carried out. The grinding fineness is -0.074mm, and the percentage of mineral particles is 70%. Water is added to adjust the concentration to 25%. Then it is subjected to flotation. Figure 1 shown.

[0024] A pH adjuster is added to the adjusted pulp to adjust the pH to 10, and then an inhibitor and a decalcification collector are added to perform a coarse-fine reverse flotation operation to obtain a concentrate K. Among them, the inhibitor (specifically aluminum sulfate and water glass with a modulus of 2.4 are mixed in a mass ratio of 1:1) and the decalcification collector (specifically composed of sodium oleate, coconut amine and sodium dodecyl sulfate, wherein sodium oleate accounts for 75wt%, coconut amine accounts for 12wt%, and sodium dodecyl sulfate accounts for 13wt%) are used in an amount of 1.0 kg / t and 0.4 kg / t of inhibitor, and 1.2kg / t and 1.0kg / t of decalcification collector. It should be noted that the inhibitors and decalcification collectors and their amounts listed in this case are only for the purpose of clearly explaining this case. Other inhibitors and decalcification collectors are also applicable to the present invention, and the protection scope of the present invention is not limited thereto.

[0025] The tailings from the coarse and fine reverse flotation operations are collected, and flocculant (polyacrylamide, dosage 1kg / t) is added for thickening. After the slurry is adjusted to a concentration of 25%, it enters the spiral chute for gravity separation to obtain a coarse-grained low-calcium product and a fine-grained high-calcium product.

[0026] The interception points of the coarse-grained low-calcium products and the fine-grained high-calcium products in the spiral chute are 4:6 in length from inside to outside, the spiral chute has a diameter ratio of 0.6 and a chute diameter of 1.2 meters.

[0027] The coarse-grained low-calcium product is subjected to a reverse flotation operation, and the dosage of the inhibitor and decalcification collector is 0.3 kg / t and 0.5 kg / t respectively. The concentrate obtained after reverse flotation is returned to the original ore for reselection, and finally the concentrate K, the fine-grained high-calcium product and the tailings X are obtained. For details, see Figure 1 .

[0028] The obtained product was tested according to GB / T14506.22-1993, and the specific results are shown in Table 1 below.

[0029] Table 1

[0030] In Example 1, the re-flotation process was used to obtain the V 2 O 5 The grade is 1.72%, the yield is 54.85%, and the recovery rate reaches 92.10%.

[0031] Example 2 A vanadium beneficiation method for high-calcium vanadium-containing shale refloatation and vanadium enrichment. The sample properties described in this example are the same as those in Example 1, but the coarse-grained low-calcium product is not returned for reselection, and medium ore II is produced, and the dosage of other reagents remains unchanged.

[0032] like Figure 1 As shown, a pH adjuster is added to the adjusted pulp to adjust the pH to 10, and then an inhibitor and a decalcified collector are added to carry out a coarse-fine reverse flotation operation to obtain a concentrate K. Among them, the dosage of the inhibitor and the decalcified collector in the coarse-fine reverse flotation operation is 1.0 kg / t and 0.4 kg / t for the inhibitor, and 1.2 kg / t and 1.0 kg / t for the decalcified collector.

[0033] The tailings from the coarse and fine reverse flotation operations are collected, thickened by adding flocculants, and then slurried to a concentration of 25% before entering the spiral chute for gravity separation to obtain a coarse-grained low-calcium product and a fine-grained high-calcium product.

[0034] The interception points of the coarse-grained low-calcium products and the fine-grained high-calcium products in the spiral chute are 4:6 in length from inside to outside, the spiral chute has a diameter ratio of 0.6, the chute diameter is 1.2 meters, the flocculant is polyacrylamide, and the dosage is 1.0kg / t.

[0035] The low-calcium product of the coarse particle size is subjected to a reverse flotation operation to produce the medium ore II. The dosage of the inhibitor and decalcification collector is 0.3 kg / t and 0.5 kg / t respectively.

[0036] Through the above experiments, concentrate K and intermediate ore II were obtained respectively, and the test results are shown in Table 2 below.

[0037] Table 2

[0038] Flotation concentrate KV obtained by gravity flotation combined separation process 2 O 5 The grade is 1.82%, the yield is 40.54%, and the recovery rate is 73.15%. Although the grade of vanadium pentoxide is enriched, the yield is significantly reduced. 2 O 5 The grade is less than 1.5%, and the calcium oxide content is relatively high, making it difficult to utilize. Therefore, it is necessary to return the middling ore II for reselection.

[0039] Example 3 A vanadium beneficiation method for refloating and enriching high-calcium vanadium-containing shale. The sample properties described in this example are the same as those in Example 1, and the interception points of the coarse-grained low-calcium product and the fine-grained high-calcium product in the spiral chute are respectively 5:5 in the chute length from the inside to the outside, and the other conditions remain unchanged.

[0040] Through the above experiments, the test results of the products obtained are shown in Table 3 below.

[0041] Table 3

[0042] Flotation concentrate KV obtained by gravity flotation combined separation process 2 O 5 The grade is 1.51%, the yield is 58.23%, the recovery rate is 87.22%, and the concentrate KV 2 O 5 The grade is significantly reduced and the CaO content is highly enriched, so when the spiral chute interception band changes, it has a greater impact on this method.

[0043] Example 4 is the same as Example 1, except that the interception points of the coarse-grained low-calcium product and the fine-grained high-calcium product in the spiral chute are 4:6 from the inside to the outside, the spiral chute has a diameter ratio of 0.6, and the chute diameter is 1.8 meters. The test results of the obtained products are shown in Table 4 below.

[0044] Table 4

[0045] Flotation concentrate KV obtained by gravity flotation combined separation process 2 O 5 The grade is 1.46%, the yield is 51.23%, the recovery is 74.77%, and the concentrate KV 2 O 5 The grade and recovery rate are significantly reduced. Increasing the diameter of the spiral chute causes more coarse-grained gravity concentrate to enter the tailings, resulting in an increase in the vanadium content in the tailings, affecting the separation effect.

[0046] Example 5 is the same as Example 1, except that the interception points of the coarse-grained low-calcium product and the fine-grained high-calcium product in the spiral chute are 4:6 from the inside to the outside, the spiral chute has a diameter ratio of 0.8, and the chute diameter is 1.2 meters. The test results of the obtained products are shown in Table 5 below.

[0047] Table 5

[0048] Flotation concentrate KV obtained by gravity flotation combined separation process 2 O 5 The grade is 1.50%, the yield is 53.86%, the recovery is 80.79%, and the concentrate KV 2 O 5The grade and recovery rate are low. Increasing the pitch-to-diameter ratio of the spiral chute while keeping the chute diameter unchanged increases the chute height, resulting in a higher flow rate at the end of the slurry. Under the influence of centrifugal force, more coarse particles are enriched in the fine-grained high-calcium tailings, affecting the mineral processing efficiency.

[0049] The above embodiments describe the preferred implementation of the present invention, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A vanadium beneficiation method for high-calcium vanadium-containing shale refloatation combined with vanadium enrichment, characterized in that: The following steps are involved: S1. The raw ore is subjected to a coarse and fine reverse flotation to obtain concentrate and tailings; S2. The tailings are re-selected using a spiral chute to obtain a coarse-grained low-calcium product and a fine-grained high-calcium product. The coarse-grained low-calcium product is decalcified and floated, and the decalcified concentrate is returned to the original ore in S1 to form a closed loop.

2. The method according to claim 1, characterized in that: In the high-calcium vanadium-containing shale ore, the V2O5 grade is 0.80%-1.20%, and the CaO content is 8.00%-12.00%. The ore is ground, slurried and the pH is adjusted to alkaline before a coarse and fine reverse flotation operation.

3. The method according to claim 1, characterized in that: When grinding and slurrying the raw ore in S1, the fineness is controlled to be 60-70% of the mineral particles with a particle size of -0.074 mm, and the slurry concentration is 20-30%; the pH is adjusted to 9.5~10.

5.

4. The method according to claim 1, characterized in that: The raw ore in S1 is added with decalcified collector and inhibitor respectively for rough and fine reverse flotation; in the roughing, the amount of decalcified collector added is 1.0 kg / t -1.1 kg / t, and the amount of inhibitor added is 1.2kg / t -1.4 kg / t; in the fine separation, the amount of decalcified collector added is 0.4 kg / t -0.5 kg / t, and the amount of inhibitor added is 1.0kg / t -1.2kg / t.

5. The method according to claim 1, characterized in that: The tailings collected in S2 are first thickened by adding flocculants and then enter the spiral chute for gravity separation.

6. The method according to claim 5, characterized in that The flocculant for thickening treatment is polyacrylamide, and the dosage is 1.0 kg / t -1.2 kg / t.

7. According to the method of claim 1, at least one of the following conditions is met during reselection in S2: the spiral chute has a diameter ratio of 0.5-0.8; the chute diameter is 0.8-1.2 meters; the ratio of the interception points from the inside to the outside of the chute length is (3~4): (6~7).

8. The method according to claim 1, characterized in that: During decalcification flotation, decalcification collector and inhibitor are added; the dosage of inhibitor and decalcification collector is 0.2 kg / t -0.5 kg / t and 0.4 kg / t -0.5 kg / t respectively.

9. The method according to any one of claims 1 to 8, characterized in that: The inhibitor is a mixture of aluminum sulfate and water glass with a modulus of 2.0-3.0 in a mass ratio of 1:1-1.

5.

10. The method according to any one of claims 1 to 8, characterized in that: The decalcification collector is composed of sodium oleate, coconut amine and sodium lauryl sulfate, wherein sodium oleate accounts for 70-75wt%, coconut amine accounts for 10-15wt%, and sodium lauryl sulfate accounts for 10-20wt%.

Images