A calcite flotation combined inhibitor and its application

Abstract

The present invention discloses a combined inhibitor for calcite flotation and its application, belonging to the technical field of mineral flotation. The combined inhibitor for calcite flotation includes fluorosulfuric acid, magnesium aluminum silicate, tartaric acid and flavanol compounds. For the first time, the present invention combines fluorosulfuric acid, magnesium aluminum silicate, tartaric acid and flavanol compounds into a combined inhibitor for calcite flotation, which synergistically inhibits calcite, improves the high recovery and high grade effects of fluorite concentrate, and the chemical properties of the combined inhibitor are stable. In addition, the present invention applies the combined inhibitor to the fluorite and calcite flotation process, and the process has good selectivity, high separation efficiency, high recovery rate, low ore dressing cost, simple and reliable process flow, and stable indexes.

Description

Technical Field

[0001] The present invention belongs to the technical field of mineral flotation, and particularly relates to a combined depressant for calcite flotation and its application. Background Art

[0002] Fluorite is a strategic mineral, the only mineral that can extract a large amount of fluorine elements. At the same time, it is also used as a flux in steelmaking to remove impurities. It plays a great role in a country's economic development and is extremely widely distributed around the world. For a long time in our country, as one of the advantageous mineral products for earning foreign exchange through exports, it has a wide range of uses and can be used in industries such as metallurgy, chemical industry, ceramics, optics, cement, and glass.

[0003] Calcite is the main mineral of limestone and marble and has many uses in production and life. Calcite is used as a flux in the metallurgical industry; in the construction industry, it is used to produce cement and lime; it is used in plastics, paper, and toothpaste; it is used as an additive in food; when calcite is added to glass production, the resulting glass will become translucent, which is especially suitable for making glass lamp shades.

[0004] The separation method of fluorite ore is not only related to the particle size of fluorite minerals, but also related to the types of gangue minerals symbiotic with it. Generally speaking, gangue minerals with high silicon content and low calcium content are easier to separate, and it is easy to obtain high-quality fluorite concentrates with high economic benefits. Gangue minerals with low silicon content and high calcium content have a complex symbiotic relationship, and their flotabilities are similar, making it relatively difficult to separate. Conventional flotation methods generally use oleic acid and its substitutes as collectors, and use water glass, sodium hexametaphosphate, tannins, etc. as regulators. However, many reports show that the inhibitory effect of water glass alone on calcite is not strong, especially when fine-grained calcite is present, the separation of fluorite and calcite is even more difficult. Therefore, to obtain high-quality fluorite concentrates, especially the separation of fluorite and calcium carbonate, a reasonable separation process and an efficient reagent system are necessary. Summary of the Invention

[0005] Aiming at the above-mentioned shortcomings of the prior art, the present invention provides a combined depressant for calcite flotation and its application.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a combined depressant for calcite flotation, comprising fluorosulfuric acid, magnesium aluminum silicate, tartaric acid, and flavanol compounds.

[0007] The flavanol compounds include three types of compounds. The first type is natural flavan-3-ols, including their dimers, a few 3-position glycosides, and gallic acid esters; the second type is flavan-3,4-diols, that is, colorless anthocyanidin aglycones; the third type is condensed proanthocyanidin aglycones.

[0008] Flavanol compounds. Flavanol is a natural plant compound that exists in Gymnocladus chinensis, cocoa, tea, red wine, fruits and vegetables, and among them, the content of flavanol in cocoa is the highest. Flavanol compounds have multiple phenolic hydroxyl groups in their structures. When inhibiting gangue minerals such as calcite, they are fixed on the surface of calcite by physical or chemical adsorption with the help of phenolic ions, with the hydroxyl groups facing outward, forming a water film with water molecules through hydrogen bonding forces, which affects the floatability of gangue minerals such as calcite.

[0009] As a preferred embodiment of the present invention, the mass percentage content of each raw material in the calcite flotation combined inhibitor: fluorosulfuric acid 10 - 30%, magnesium aluminum silicate 30 - 50%, tartaric acid 30 - 50%, flavanol compounds 10 - 30%.

[0010] The application of the calcite flotation combined inhibitor in the flotation separation of fluorite and calcite.

[0011] As a preferred embodiment of the present invention, the flotation separation of calcite and fluorite is carried out under the condition that the pH is 8 - 11 by using the calcite flotation combined inhibitor.

[0012] Under slightly alkaline conditions of the present invention, tartaric acid and flavanol compounds can significantly enhance the surface hydrophilicity of calcite and have a selective inhibitory effect on calcite. Flavanol compounds have both chemical adsorption and physical adsorption on fluorite and calcite. The action mode is that there is a direct Ca - O chemical bond between the phenolic hydroxyl group at the molecular end and the surface particles of calcite, the activated Ca - O chemical bond, hydrogen bond and electrostatic attraction; under ideal conditions, there is an interconversion between fluorite and calcite, and the critical pH for the conversion is 8.5. Therefore, the combined inhibitor described in this patent is used in combination within the pH range of 8 - 11 to inhibit calcite, so as to achieve the separation purpose.

[0013] As a preferred embodiment of the present invention, the application includes the following steps:

[0014] (1) Grind the ore containing fluorite and calcite, add water, and adjust the pH value to 8 - 11 with sodium carbonate to obtain pulp;

[0015] (2) Add a fatty acid collector and a foaming agent to the pulp, act for 1 minute, and conduct a primary rough selection to mix and select into a fluorite - calcite mixed concentrate;

[0016] (3) Add the calcite flotation combined inhibitor to the mixed concentrate, act for 1 minute, and then heat the pulp temperature to 30 - 35 °C for cleaning to obtain a cleaned pulp;

[0017] (4) Filter the cleaned pulp, add a foaming agent and the calcite flotation combined inhibitor to the filtered cleaned pulp for secondary cleaning;

[0018] (5) Repeat step (4) for 3 to 6 times of selection to obtain fluorite concentrate and tailings.

[0019] As a preferred embodiment of the present invention, the fineness of grinding is such that the content of -0.074 mm accounts for 75%.

[0020] As a preferred embodiment of the present invention, in step (3), the dosage of the calcite flotation combined inhibitor is 600 g / t.

[0021] As a preferred embodiment of the present invention, in step (4), the dosage of the calcite flotation combined inhibitor is 50 g / t.

[0022] As a preferred embodiment of the present invention, the dosage of the fatty acid collector is 300 g / t.

[0023] As a preferred embodiment of the present invention, in step (4), the dosage of the foaming agent is 300 g / t; the foaming agent is a conventional foaming agent.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention first compounded fluorosulfuric acid, magnesium aluminum silicate tartaric acid and flavanol compounds into a calcite flotation combined inhibitor, which synergistically inhibits calcite, improves the high recovery and high grade effect of fluorite concentrate, and the combined inhibitor has stable chemical properties. In addition, the present invention applies the combined inhibitor to the fluorite and calcite flotation process, and the process has good selectivity, high separation efficiency, high recovery rate, low beneficiation cost, simple and reliable process flow, and stable indexes. Detailed Embodiments

[0025] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0026] Example 1

[0027] The calcite flotation combined inhibitor in this example comprises raw materials with the following mass percentages: 15% of fluorosulfuric acid, 35% of magnesium aluminum silicate, 35% of tartaric acid, and 15% of flavanol compounds.

[0028] In this example, the flavanol compounds are natural flavan-3-ols; the foaming agent is pine oil; the ore containing fluorite and calcite is a certain fluorite ore in Hunan, and the fluorite ore contains 38.01% of CaF 2 , 6.85% of CaCO 3 and 51.19% of SiO 2 , and -200 mesh in the ore accounts for -65%; the fatty acid collector is oleic acid.

[0029] The application of the calcite flotation combined inhibitor in the flotation separation of fluorite and calcite comprises the following steps:

[0030] (1) Grind the ore containing fluorite and calcite, add water, and adjust the pH value to 8 - 11 with sodium carbonate to obtain pulp; the fineness of grinding is such that the content of -0.074mm accounts for 75%;

[0031] (2) Add 300g / t of fatty acid collector and frother to the pulp, let it act for 1 minute, and conduct a rough selection to mix and select a fluorite - calcite mixed concentrate;

[0032] (3) Add 600g / t of calcite flotation combination inhibitor to the mixed concentrate, let it act for 1 minute, and then heat the pulp temperature to 35°C for cleaning to obtain a cleaned pulp;

[0033] (4) Filter the cleaned pulp, and add 300g / t of frother and 50g / t of calcite flotation combination inhibitor to the filtered cleaned pulp for secondary cleaning;

[0034] (5) Repeat step (4) for 6 times of cleaning to obtain fluorite concentrate and tailings.

[0035] Example 2

[0036] The calcite flotation combination inhibitor described in this example comprises raw materials with the following mass percentages: 10% of fluorosulfuric acid, 30% of magnesium aluminum silicate, 50% of tartaric acid, and 10% of flavanol compounds.

[0037] The flavanol compounds are flavan - 3,4 - diols; the frother is pine oil; the ore containing fluorite and calcite is a certain fluorite ore in Hunan, and the fluorite ore contains 38.01% of CaF 2 , 6.85% of CaCO 3 and 51.19% of SiO 2 , and the -200 mesh in the ore accounts for -65%; the fatty acid collector is oleic acid.

[0038] The application of the calcite flotation combination inhibitor in the flotation separation of fluorite and calcite comprises the following steps:

[0039] (1) Grind the ore containing fluorite and calcite, add water, and adjust the pH value to 8 - 11 with sodium carbonate to obtain pulp; the fineness of grinding is such that the content of -0.074mm accounts for 75%;

[0040] (2) Add 300g / t of fatty acid collector and frother to the pulp, let it act for 1 minute, and conduct a rough selection to mix and select a fluorite - calcite mixed concentrate;

[0041] (3) Add 600g / t of calcite flotation combination inhibitor to the mixed concentrate, let it act for 1 minute, and then heat the pulp temperature to 30°C for cleaning to obtain a cleaned pulp;

[0042] (4) Filter the selected pulp, and add 300 g / t of foaming agent and 50 g / t of calcite flotation combined inhibitor to the filtered selected pulp for secondary selection;

[0043] (5) Repeat step (4) for three times of selection to obtain fluorite concentrate and tailings.

[0044] Example 3

[0045] The calcite flotation combined inhibitor described in this example comprises raw materials with the following mass percentages: 10% of fluorosulfuric acid, 50% of magnesium aluminum silicate, 30% of tartaric acid, and 10% of flavanol compounds.

[0046] The flavanol compounds are flavan-3,4-diols; the foaming agent is pine oil; the ore containing fluorite and calcite is a certain fluorite ore in Hunan, and the fluorite ore contains 38.01% of CaF 2 , 6.85% of CaCO 3 and 51.19% of SiO 2 , and -200 mesh in the ore accounts for -65%; the fatty acid collector is oleic acid.

[0047] The application steps of the calcite flotation combined inhibitor in the flotation separation of fluorite and calcite are the same as those in Example 1.

[0048] Example 4

[0049] The calcite flotation combined inhibitor described in this example comprises raw materials with the following mass percentages: 10% of fluorosulfuric acid, 30% of magnesium aluminum silicate, 30% of tartaric acid, and 30% of flavanol compounds.

[0050] The flavanol compounds are flavan-3,4-diols; the foaming agent is pine oil; the ore containing fluorite and calcite is a certain fluorite ore in Hunan, and the fluorite ore contains 38.01% of CaF 2 , 6.85% of CaCO 3 and 51.19% of SiO 2 , and -200 mesh in the ore accounts for -65%; the fatty acid collector is oleic acid.

[0051] The application steps of the calcite flotation combined inhibitor in the flotation separation of fluorite and calcite are the same as those in Example 1.

[0052] Example 5

[0053] The calcite flotation combined inhibitor described in this example comprises raw materials with the following mass percentages: 30% of fluorosulfuric acid, 30% of magnesium aluminum silicate, 30% of tartaric acid, and 10% of flavanol compounds.

[0054] The flavanol compound is a flavan-3,4-diol; the foaming agent is pinitol; the ore containing fluorite and calcite is a certain fluorite ore in Hunan, and the fluorite ore contains 38.01% CaF 2 , 6.85% CaCO 3 and 51.19% SiO 2 , and -200 mesh in the ore accounts for -65%; the fatty acid collector is oleic acid.

[0055] The application steps of the calcite flotation combined inhibitor in the flotation separation of fluorite and calcite are the same as those in Example 1.

[0056] Comparative Example 1

[0057] The treatment of the application steps in this comparative example is the same as that in Example 1, except that: the calcite flotation combined inhibitor in each flotation operation section is replaced with water glass of the same mass. The grade and recovery rate of the concentrate product obtained in Comparative Example 1 are shown in Table 1.

[0058] Comparative Example 2

[0059] The calcite flotation combined inhibitor in this comparative example is fluorosulfuric acid.

[0060] The treatment of the application steps in this comparative example is the same as that in Example 1. The grade and recovery rate of the concentrate product obtained in Comparative Example 2 are shown in Table 1.

[0061] Comparative Example 3

[0062] The calcite flotation combined inhibitor in this comparative example includes 50% magnesium aluminum silicate, 35% tartaric acid, and 15% flavanol compound.

[0063] The treatment of the application steps in this comparative example is the same as that in Example 1. The grade and recovery rate of the concentrate product obtained in Comparative Example 3 are shown in Table 1.

[0064] Comparative Example 4

[0065] The calcite flotation combined inhibitor in this comparative example is magnesium aluminum silicate.

[0066] The treatment of the application steps in this comparative example is the same as that in Example 1. The grade and recovery rate of the concentrate product obtained in Comparative Example 4 are shown in Table 1.

[0067] Comparative Example 5

[0068] The calcite flotation combined inhibitor in this comparative example includes 30% fluorosulfuric acid, 50% tartaric acid, and 20% flavanol compound.

[0069] The treatment of the application steps in this comparative example is the same as that in Example 1. The grade and recovery rate of the concentrate product obtained in Comparative Example 5 are shown in Table 1.

[0070] Comparative Example 6

[0071] The calcite flotation combined inhibitor described in this comparative example is tartaric acid.

[0072] The application steps of this comparative example are the same as those of Example 1. The grades and recovery rates of the concentrate products obtained in Comparative Example 6 are shown in Table 1.

[0073] Comparative Example 7

[0074] The calcite flotation combined inhibitor described in this comparative example includes 30% fluorosulfuric acid, 50% magnesium aluminum silicate, and 20% flavanol compounds.

[0075] The application steps of this comparative example are the same as those of Example 1. The grades and recovery rates of the concentrate products obtained in Comparative Example 7 are shown in Table 1.

[0076] Comparative Example 8

[0077] The calcite flotation combined inhibitor described in this comparative example is flavanol compounds.

[0078] The application steps of this comparative example are the same as those of Example 1. The grades and recovery rates of the concentrate products obtained in Comparative Example 8 are shown in Table 1.

[0079] Comparative Example 9

[0080] The calcite flotation combined inhibitor described in this comparative example includes 30% fluorosulfuric acid, 35% magnesium aluminum silicate, and 35% tartaric acid.

[0081] The application steps of this comparative example are the same as those of Example 1. The grades and recovery rates of the concentrate products obtained in Comparative Example 9 are shown in Table 1.

[0082] Comparative Example 10

[0083] The calcite flotation combined inhibitor described in this comparative example is the same as that in Example 1.

[0084] The only difference between the application of the calcite flotation combined inhibitor described in this comparative example in the flotation separation of fluorite and calcite and Example 1 is that: in step (1), the pH value is 5.

[0085] Table 1

[0086]

[0087]

[0088] As can be seen from Table 1, the effects of Examples 1-5 are better than those of Comparative Examples 1-10, indicating that the calcite flotation combined inhibitor of the present invention can effectively and selectively inhibit calcite. Comparing Comparative Examples 2-9 with the Examples, when fluorosulfuric acid, magnesium aluminum silicate, tartaric acid or flavanol compounds are used alone or a certain component is missing in the combined inhibitor, the recovery rate and grade of fluorite concentrate are not as high as those with the combined inhibitor, indicating that fluorosulfuric acid, magnesium aluminum silicate, tartaric acid or flavanol compounds synergize with each other to achieve the inhibition of calcite and effectively recover fluorite concentrate. Fluorosulfuric acid can oxidize the surface of calcite. Magnesium aluminum silicate forms an "associated network structure" in the aqueous medium, which can stably, effectively and homogeneously lift and suspend solid particles, emulsions and gases in the system, preventing them from sinking due to gravity and better improving the performance of the suspension system. Tartaric acid and flavanol compounds contain carboxyl, phenolic and hydroxyl groups in their structures, which can produce physical and chemical adsorption on the surface of calcite, increase the hydrophilicity of calcite and reduce its flotation recovery rate. Fluorosulfuric acid, magnesium aluminum silicate, tartaric acid and flavanol compounds can not only play their own advantages, but also interact with each other, significantly improving the recovery rate and grade of fluorite concentrate. According to Comparative Example 10 and Example 1, the calcite flotation combined inhibitor of the present invention is used for the flotation separation of calcite and fluorite under the condition of pH 8-11. Under slightly alkaline conditions, tartaric acid and flavanol compounds can significantly enhance the surface hydrophilicity of calcite and have a selective inhibitory effect on calcite, thus realizing the separation of fluorite and calcite.

[0089] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A combined inhibitor for calcite flotation, characterized in that, it comprises raw materials with the following mass percentages: 10 - 30% of fluorosulfuric acid, 30 - 50% of magnesium aluminum silicate, 30 - 50% of tartaric acid, and 10 - 30% of flavanol compounds.

2. Use of the combined inhibitor for calcite flotation according to claim 1 in the flotation separation of fluorite and calcite.

3. The use according to claim 2, characterized in that, the combined inhibitor for calcite flotation is used for the flotation separation of calcite and fluorite under the condition that the pH is 8 - 11.

4. The use according to claim 3, characterized in that, it comprises the following steps: (1) Grinding the ore containing fluorite and calcite and adding water, and adjusting the pH value to 8 - 11 with sodium carbonate to obtain pulp; (2) Adding a fatty acid collector and a foaming agent to the pulp, acting for 1 minute, and performing a rough selection to mix and select a fluorite - calcite mixed concentrate; (3) Adding the combined inhibitor for calcite flotation to the mixed concentrate, acting for 1 minute, and then heating the pulp temperature to 30 - 35 °C for cleaning to obtain a cleaned pulp; (4) Filtering the cleaned pulp, adding a foaming agent and the combined inhibitor for calcite flotation to the filtered cleaned pulp for secondary cleaning; (5) Repeating step (4) for cleaning 3 - 6 times to obtain a fluorite concentrate and tailings.

5. The use according to claim 4, characterized in that, the fineness of grinding is that the content of - 0.074 mm accounts for 75%.

6. The use according to claim 4, characterized in that, in step (3), the dosage of the combined inhibitor for calcite flotation is 600 g / t.

7. The use according to claim 4, characterized in that, in step (4), the dosage of the combined inhibitor for calcite flotation is 50 g / t.

8. The use according to claim 4, characterized in that, the dosage of the fatty acid collector is 300 g / t.

9. The use according to claim 4, characterized in that, in step (4), the dosage of the foaming agent is 300 g / t.

Images