Combined collecting agent, flotation reagent and method for scheelite flotation

Abstract

The invention belongs to the field of flotation, and particularly relates to a combined collecting agent, a flotation reagent and a flotation method for scheelite flotation. The combined collecting agent comprises a component A and a component B, the component A comprises a compound # imgabs 0 # with a structure shown in a formula 1; the component B comprises a compound with a structure shown in a formula 2 # imgabs 1 #; in the combined collecting agent, the weight content of the component A is larger than or equal to 40%. According to the method, the scheelite concentrate with the high WO3 grade can be obtained through one-time concentration, the WO3 enrichment ratio exceeds 10, and the flotation recovery rate is high. The combined collecting agent is simple in component and environmentally friendly, the loss rate of scheelite in flotation tailings is low, and efficient flotation of the scheelite and flotation separation between the scheelite and calcium-containing gangue minerals can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of mineral processing and beneficiation, and relates to an application of a composite in the normal-temperature flotation of scheelite. Background Art

[0002] Scheelite (CaWO4) is widely distributed in Hunan, Jiangxi, Fujian and other regions, but the ore grade is generally low, the mineral composition is complex, and it is often associated with other minerals such as fluorite, calcite, apatite, quartz and other minerals, and is a difficult ore to select. Therefore, the mining and utilization of scheelite resources has become increasingly important.

[0003] As mentioned above, scheelite often presents a complex symbiotic relationship with calcium-containing gangue minerals such as fluorite (CaF2), calcite (CaCO3), apatite (Ca5(PO4)3OH), etc., and these calcium-containing minerals have similar surface physical and chemical properties, similar Ca active sites, and similar floatability. Therefore, achieving efficient flotation separation between scheelite and these calcium-containing gangue minerals, especially fluorite and calcite, is the focus and difficulty of current scheelite flotation research.

[0004] In order to solve this world problem, flotation collectors with strong collection ability and good selectivity are the key to research. Fatty acid collectors have been widely used in the flotation of scheelite for a long time because of their strong collection ability, but their selectivity is poor. Therefore, for scheelite deposits with high calcium gangue mineral content, their flotation indicators are generally poor; chelate collectors have good selectivity and are often used in the flotation of scheelite and wolframite to obtain good flotation indicators, but the synthesis steps of chelate collectors are relatively complicated and the cost of reagents is relatively high, so it is difficult to put them into practice when used alone to flot scheelite. Therefore, for the flotation of scheelite, the selection of collectors with both high selectivity and strong collection ability is the top priority. However, studies have shown that it is often difficult for a single collector to have both high selectivity and strong collection ability at the same time. Therefore, the mixed use of multiple different types of collectors can not only enhance their collection ability, but also significantly increase the selectivity of reagents due to the synergistic effect between reagents, which is of great significance for the efficient and clean flotation separation of scheelite.

[0005] Therefore, there is a need in the art for a composite reagent with strong collection ability and high selectivity for the flotation of scheelite, so as to achieve efficient flotation separation between scheelite and calcium-containing gangue minerals such as calcite and fluorite. Summary of the invention

[0006] In order to solve the problem that the flotation collector cannot have both the collecting ability and selectivity when flotating scheelite using the existing flotation technology, resulting in the difficulty in separating scheelite from calcium-containing gangue minerals, the present invention provides a scheelite flotation combined collector (also called a composite collector) with simple composition, strong selectivity and strong collecting ability, which significantly improves the flotation recovery rate and grade of scheelite and effectively reduces the content of calcium-containing gangue minerals such as calcite and fluorite in the rough concentrate.

[0007] Another object of the present invention is to provide an application case of a composite reagent comprising the combined collector in the selective separation of scheelite and calcium-containing gangue.

[0008] A combined collector comprises component A and component B; the component A comprises a compound having a structure of formula 1; the component B comprises a compound having a structure of formula 2;

[0009]

[0010] R1 is an alkyl group; M is H, K or Na, and n is an integer of 2 to 6;

[0011] The Ar is an aromatic group;

[0012] In the combined collector, the weight content of component A is ≥40%.

[0013] The present invention innovatively discovered that the combination of free NH at position 3 and above and its monoacylated structure in formula 1 can achieve synergy and improve its capture capacity and selectivity in scheelite. In addition, the combination of the aromatic methyl structure and the trisubstituted number and P=O structure in formula 2 can achieve synergy and optimize its capture capacity and selectivity in scheelite. Further, the combination of formula 1 and formula 2 of the structure can achieve intermolecular targeted enhancement on the basis of intramolecular synergy, which can further synergistically improve the flotation capacity and selectivity of scheelite.

[0014] In the present invention, in Formula 1, R1 is C 10 ~C 20 The alkyl group may further be a straight-chain alkyl group; the n may further be 2 to 3.

[0015] In the present invention, in Formula 2, Ar is a phenyl group or an alkyl-substituted phenyl group.

[0016] In the present invention, the separation effect can be significantly improved by controlling the ratio of each reagent in the combined collector, and the separation effect between scheelite and calcium-containing gangue, especially fluorite, can be further improved;

[0017] Preferably, in the combined collector, the weight content of component A is 40-75%, preferably 50-70%. The invention has found through experiments that under the synergistic effect of the reagents of formula 1 and formula 2, by mixing and adding auxiliary collectors such as sodium oleate, the selectivity of the reagents can be ensured while further improving the collection capacity of scheelite.

[0018] In the present invention, the ratio of component A to component B may be 2 to 3:1.

[0019] The combined collector further comprises component C, which comprises oleic acid and its salt.

[0020] In the combined collector, the weight content of component C is ≤25%, preferably 5 to 25%, and more preferably 10 to 20%.

[0021] The present invention further provides a composite flotation reagent, which comprises the combined collector of the present invention.

[0022] The composite pharmaceutical composition of the present invention comprises an inhibitor;

[0023] The inhibitor may be a conventional calcium-containing gangue inhibitor, for example, at least one of sodium fluorosilicate and water glass.

[0024] The present invention also provides a method for flotation of scheelite, wherein the ore to be selected including scheelite and a flotation agent are mixed for flotation to obtain scheelite concentrate; the flotation agent comprises the combined collector of the present invention.

[0025] The flotation reagent is the flotation reagent described in the present invention;

[0026] Preferably, the mineral to be selected further comprises gangue minerals, and the gangue minerals include calcium-containing gangue;

[0027] Preferably, the calcium-containing gangue includes at least one of calcite and fluorite.

[0028] In the present invention, the amount of the combined collector in the flotation stage is 300-1500 g / t, further 500-1200 g / t, and further 600-1000 g / t in consideration of the effect and composition. In the present invention, the amount of the combined collector in the roughing flotation can be 300-600 g / t.

[0029] Preferably, the dosage of the inhibitor is 1500-4500 g / t, preferably 2000-4000 g / t.

[0030] Preferably, the pH of the flotation stage is 7 to 10.5, preferably 7.5 to 8.5.

[0031] Preferably, the pulp temperature during flotation operation is -5 to 40°C; further, it can be 20 to 30°C.

[0032] At the same time, the present invention provides a process flow for flotation separation of calcium-containing scheelite, which adopts the flotation agent for flotation separation, and obtains high-grade scheelite concentrate through two concentrations. The calcium gangue content in the concentrate, especially fluorite, is low.

[0033] Beneficial effects:

[0034] 1. The combination of free NH at position 3 and above of formula 1 and its monoacylated structure can achieve synergy and improve its capture capacity and selectivity in scheelite. In addition, the combination of the aromatic methyl structure and the trisubstituted number and P=O structure in formula 2 can achieve synergy and optimize its capture capacity and selectivity in scheelite. Further, the combination of formula 1 and formula 2 of the structure can achieve intermolecular targeted enhancement on the basis of intramolecular synergy, which can further synergistically improve the flotation capacity and selectivity of scheelite.

[0035] The combined collector of the present invention has both strong collecting ability and strong selectivity. It has poor collecting ability for calcium-containing gangue minerals, especially fluorite, and can effectively solve the problems of poor selectivity of traditional fatty acid collectors, large amounts of fluorite and calcite mixed in the concentrate, resulting in low WO3 grade and unsatisfactory flotation indicators.

[0036] 2. The combined collector provided by the present invention is used in the flotation of scheelite, and has good flotation effects under neutral and alkaline pulp conditions, a wide tolerance to pulp pH, and is insensitive to changes in flotation pulp temperature. The flotation indicators are better at lower temperatures;

[0037] 3. The combined collector provided by the present invention has the advantages of good flotation effect, strong collecting ability, strong reagent selectivity and no pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The XRD analysis results of the mineral composition of the scheelite ore used in the present invention;

[0039] Figure 2 It is a flow chart of the closed-circuit flotation test of the present invention. DETAILED DESCRIPTION

[0040] Embodiment 1:

[0041] 1. Select the original scheelite ore from a certain place for flotation experiment, Figure 1Table 1 and Table 1 are the semi-quantitative analysis results of XRD of scheelite ore. The main useful minerals in the ore are scheelite, chalcopyrite, etc., among which the WO3 content is 0.50%. The main gangue minerals are quartz, pyroxene, (clinopyroxene, sodium) feldspar, mica, chlorite, amphibole, calcite, fluorite, etc., among which the fluorite content is about 6.13% and the calcite content is about 7.44%.

[0042] Table 1 Relative composition of raw ore minerals

[0043] mineral Chlorite talc amphibole Mica quartz Calcite content(%) 7.95 5.78 7.87 5.96 16.33 7.44 mineral Scheelite fluorite Pyroxene Feldspar other content(%) 0.67 6.13 16.79 23.30 1.78

[0044] 2. The raw ore was crushed and screened to less than -2 mm, and then fully mixed and bagged for storage. A laboratory small ball mill was used to put 700 g of raw ore and 350 g of tap water into it, and the ore was ground to -200 mesh (-74 μm), accounting for 76%;

[0045] 3. Flotation process Figure 2 , pour the slurry into a 1.5L aerated flotation machine, adjust the slurry pH to about 8.0 (±0.1), then add 3.0kg / t sodium fluorosilicate as an inhibitor, and the slurry mixing time is 3 minutes; finally, add a combined collector (or a single collector for comparison), the collector dosage is 400g / t, the slurry mixing time is 3 minutes, the roughing time is 8 minutes, and only the combined collector is added in the scavenging stage, the dosage of the combined collector is half of that in the previous stage, the scavenging operation times are 3 times, the middling products obtained by flotation are returned in sequence, and the obtained rough concentrate is subjected to one-stage concentrating to obtain tungsten concentrate;

[0046] In this case, the collector selected in Formula 1 has n=2, R1 is n-dodecyl C 12 H 25 , M is H. It should be noted that M in the flotation stage can be partially or completely converted into a salt type (M is K or Na) according to the control of pH in the flotation stage. The formula 2 refers to the collector of formula 2 in which Ar is phenyl.

[0047] The flotation temperature is 25-30°C.

[0048] 6. Weigh the flotation products, then assay the flotation products, measure the grade of WO3 in each flotation product, and calculate the recovery rate, yield and grade of each flotation product.

[0049] The composition of the collectors in each experimental group of Example 1 and the flotation results are shown in Table 1:

[0050] Table 1

[0051]

[0052]

[0053] Note: In Table 1, the total amount of collector used in each experimental group is the same;

[0054] Comparison formula a:

[0055] Contrast formula b: n = 2;

[0056] Contrast formula c:

[0057] Contrast formula d: The structure is similar to Formula 1, R1 and M are the same as Formula 1 in this case, and n=1;

[0058] Contrast formula e:

[0059] Formula 1A: Formula 1, wherein R1 is n-hexadecyl, n=3, and M is Na;

[0060] As shown in the table above, the WO3 grade of the original ore is 0.500%. By comparing Group A and Group B, it can be seen that the combination of Formula 1 and Formula 2 in the combined collector has a strong inhibitory effect on calcite and fluorite in the original ore, but the flotation recovery rate of tungsten ore is relatively high. As a preferred embodiment, when the weight content ratio of Formula 1 and Formula 2 collectors is 2 to 3:1, the effect is best, and the grade and recovery rate of the flotation concentrate are relatively high;

[0061] By comparing Group A, Group B and Comparative Groups 1, 2 and 3, it can be seen that when Formula 1, Formula 2 and auxiliary collector act alone, the flotation effect is poor, and the grade and recovery rate of scheelite concentrate are both low;

[0062] By comparing Group A, Group B and Comparative Group 4, it can be seen that the weight content of Formula 1 in the combined collector must be no less than 40%. When the content of Formula 1 collector is low, the flotation index is poor.

[0063] By comparing group B with comparison groups 5 to 9, it can be seen that the combined control of the structures of formula 1 and formula 2 is the key to determining the strong capture ability and selectivity of the combined collector.

[0064] Example 2

[0065] The flotation method of Example 2 is the same as that of Example 1, the main difference being the addition of an auxiliary collector, sodium oleate. The other flotation conditions are the same as those of the example, and the flotation results are shown below (Table 2):

[0066] Table 2

[0067]

[0068]

[0069] As shown in the table above, by comparing Group A of Example 1 with Group A of Example 2, it can be seen that after adding the auxiliary collector sodium oleate, the WO3 grade in the flotation concentrate increased significantly by about 1.5%, and the calcite and fluorite contents in the concentrate decreased significantly (both ≥ 1.4%). While ensuring the selectivity of the reagent, the collection capacity of the combined collector increased significantly, and the WO3 recovery rate increased by more than 10%;

[0070] By comparing groups A to C of Example 2, when the weight content of sodium oleate is low, the recovery rate of the flotation concentrate decreases by about 5%, and the grade decreases by a small margin, indicating that the optimal weight content range of sodium oleate is 5 to 25%, and further 10 to 20%; when the dosage of sodium oleate is too high, the synergistic effect between the reagents deteriorates, and at this time, the grade and recovery rate of WO3 in the flotation concentrate are both reduced.

[0071] Example 3

[0072] The flotation method of Example 3 is consistent with that of Examples 1 and 2, and the weight content ratio of the combined collector used is consistent with that of Group A of Example 2. The main difference is that the flotation index difference is determined by changing the flotation pH, the amount of inhibitor, the amount of combined collector, etc. The final flotation results of each group are shown in Table 3:

[0073] Table 3

[0074]

[0075]

[0076] Note: The dosage of inhibitors and collectors in Table 3 refers to the dosage of reagents in the roughing process. The dosage of combined collectors in other flotation processes is halved step by step in the manner of Example 1.

[0077] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A combined collector, characterized in that: It comprises component A and component B; the component A comprises a compound having a structure of formula 1; the component B comprises a compound having a structure of formula 2; R1 is an alkyl group; M is H, K or Na, and n is an integer of 2 to 6; The Ar is an aromatic group; In the combined collector, the weight content of component A is ≥40%.

2. The combined collector according to claim 1, characterized in that In the formula 1, R1 is C 10 ~C 20 The alkyl group; wherein n is 2 or 3; Preferably, Ar is a phenyl group or an alkyl-substituted phenyl group.

3. The combined collector according to claim 1, characterized in that In the combined collector, the weight content of component A is 40-75%, preferably 50-70%.

4. The combined collector according to any one of claims 1 to 3, characterized in that: The invention also comprises component C, wherein the component C comprises oleic acid and its salt.

5. The combined collector according to claim 4, characterized in that In the combined collector, the weight content of component C is ≤25%, preferably 5 to 25%, and more preferably 10 to 20%.

6. A composite flotation reagent comprising a collector and a depressant, characterized in that: The collector comprises the combined collector according to any one of claims 1 to 5.

7. The composite flotation reagent according to claim 6, characterized in that: The inhibitor comprises at least one of sodium fluorosilicate and water glass.

8. A method for flotation of scheelite, comprising mixing a mineral to be selected including scheelite with a flotation agent for flotation to obtain scheelite concentrate; characterized in that: The flotation reagent comprises the combined collector according to any one of claims 1 to 5.

9. The method for flotation of scheelite according to claim 8, characterized in that: The flotation reagent is the flotation reagent according to any one of claims 6 to 7; Preferably, the mineral to be selected further comprises gangue minerals, and the gangue minerals include calcium-containing gangue; Preferably, the calcium-containing gangue includes at least one of calcite and fluorite.

10. The method according to claim 8 or 9, characterized in that In the flotation stage, the dosage of the combined collector is 300-1500 g / t, further 500-1200 g / t, and further 600-1000 g / t; Preferably, the dosage of the inhibitor is 1500 to 4500 g / t, preferably 2000 to 4000 g / t; Preferably, the pH of the flotation stage is 7 to 10.5, preferably 7.5 to 8.5.

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