A method for improving the froth of a double reverse flotation of a siliceous calcareous phosphate rock

Abstract

The application belongs to the technical field of phosphate ore dressing, and particularly discloses a method for improving double reverse flotation froth of siliceous-calcitic collophanite, which comprises the following steps: first, adjusting the pH of the phosphate ore slurry to be acidic by oxalic acid, adding a demagnesium collector to perform reverse flotation demagnesium, obtaining a demagnesium concentrate slurry, adding active carbon to the demagnesium concentrate slurry and mixing, then diluting the slurry, adjusting the pH value to 6.5-8, adding a foam inhibitor and mixing; adding a cationic collector to perform reverse flotation for removing aluminum and silicon, and performing solid-liquid separation on the reverse flotation slurry to obtain a phosphate concentrate. The method provided by the application adjusts the pH by using oxalic acid when performing reverse flotation demagnesium, and after demagnesium, the slurry is mixed with active carbon to adsorb the reagent, and a foam inhibitor is added; then, reverse flotation is performed for removing aluminum and silicon, which can change the physicochemical properties of the froth surface, greatly shorten the half-life of the froth, and ensure the ore dressing effect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of phosphate ore dressing, and relates to a method for improving flotation froth in a double-reverse process of siliceous-calcic collophanite. BACKGROUND

[0002] Collophanite is a collection of phosphate as the main associated minerals containing calcium, magnesium, aluminum and iron, etc. Most collophanite cannot be directly used for chemical production and needs to be treated by ore dressing and impurity removal.

[0003] The double-reverse flotation process is an effective means for comprehensive development and utilization of medium-low grade siliceous-calcic collophanite resources, which removes aluminosilicate gangue by reverse flotation first and then removes carbonate gangue by reverse flotation or removes carbonate gangue by reverse flotation first and then removes silicate gangue by reverse flotation. In the double-reverse flotation process, the problems such as large amount of flotation froth, large froth viscosity and poor flowability are important factors restricting the continuous operation of production. The flotation of oxidized ore with cationic collectors has strong foaming performance, and the froth of amine cation has small surface tension. A large amount of froth forms a dense and stable froth layer. The residual collectors or Ca2+, Mg2+, PO3-4and SO2-4in the ore pulp cause the deterioration of the flotation froth and the decrease of the selectivity of the collectors. In addition, a part of slime is generated in the grinding process, which not only reduces the selectivity of the collectors but also makes the flotation froth viscous.

[0004] CN112058503A discloses a double-reverse flotation process for siliceous-calcic collophanite, which removes magnesium by reverse flotation, removes magnesium from the coarse concentrate by reverse flotation, dehydrates and slurries, removes silicon by reverse flotation, etc. The final concentrate is obtained. The process uses cationic collectors with foaming performance in the aluminum removal stage, and the froth has the characteristics of large amount of froth, strong steel and strong stability. However, phosphoric acid is used as a pH regulator in the reverse flotation process for removing magnesium, and the introduction of PO3-4in the flotation system will exacerbate the froth problem caused by cations.

[0005] CN105562213A discloses a preparation method of a phosphorite reverse flotation inhibitor, sulfuric acid, which crushes the phosphorite and uses sulfuric acid for slurry preparation as a reverse flotation inhibitor. Although it can realize local material selection and low cost, using sulfuric acid as an inhibitor, the process flow is complex, the number of operations and dosing points is large, the amount of sulfuric acid is large, and the operation control is difficult, and the equipment and pipeline scaling is serious.

[0006] CN118477759A discloses an inhibitor for flotation upgrading and impurity reduction of calcium-magnesium phosphate ore and its application, which uses organic acid and inorganic salt compound as an inhibitor and uses conventional fatty acid or amine reagent as a collector to realize effective flotation separation of the phosphate ore. However, the residual collectors or Ca2+, Mg2+, PO3-4and SO2-4in the ore pulp are not treated, which leads to relatively difficult control of the flotation froth.

[0007] The cationic collector commonly used in the market for floating the oxide ore has strong foaming performance, and the amine cation floating foam has small surface tension, and a large amount of foam forms a dense and stable foam layer, which is not suitable for direct application in production. SUMMARY

[0008] The application provides a method for improving the foam of double reverse flotation of siliceous-calcic collophanite, which can weaken the mutual influence of anion and cation collectors, reduce the influence of inevitable ions, inhibit the foaming performance of cation collectors, increase the surface tension of foam, and improve the flowability of cation flotation foam, thereby improving the utilization rate of medium and low grade siliceous-calcic collophanite.

[0009] In order to achieve the above-mentioned target, the application adopts the following technical scheme: a method for improving the foam of double reverse flotation of siliceous-calcic collophanite, comprising the following steps:

[0010] S1, adjusting the pH of the phosphate ore slurry to be acidic by oxalic acid, adding a demagnetizing collector for reverse flotation demagnetization, and obtaining a demagnetized concentrate slurry;

[0011] S2, adding active carbon to the demagnetized concentrate slurry and mixing, then diluting the slurry, adjusting the pH value to 6.5-8, and adding a foam inhibitor and mixing;

[0012] S3, adding a cationic collector to S2 for reverse flotation of aluminum and silicon, and obtaining phosphate concentrate through solid-liquid separation of the reverse flotation slurry.

[0013] Optionally, the P2O5 grade of the phosphate ore in the phosphate ore slurry is 20-30 wt%, the Al2O3 grade is 2.0-7.0 wt%, and the MgO grade is 1.0-5.0 wt%.

[0014] Optionally, the concentration of the phosphate ore slurry in S1 is 30-35 wt%, and the pH is adjusted to 4-5 by oxalic acid.

[0015] Optionally, the demagnetizing collector in S1 is XF-01, and the addition amount is 0.5-2.5 kg / t.

[0016] Optionally, the addition amount of the active carbon in S2 is 30-200 g / t, and the mixing time after addition is more than 10 minutes.

[0017] Optionally, the water used for dilution in S2 is the water obtained after solid-liquid separation in S3, and the slurry concentration is diluted to 15-30 wt%; the pH is adjusted by sodium carbonate and / or sodium bicarbonate.

[0018] Optionally, the foam inhibitor is one or more of polyether compounds, high-grade carbon alcohol, or silicone oil defoaming agent; it is prepared into a solution of 5-15%, and the addition amount is 30-300 g / t.

[0019] Optionally, the antifoam agent satisfies at least one of the following conditions: the polyether compound is polyoxyethylene ether, glycerol and / or polyethylene glycol; the higher carbon alcohol is n-butanol, n-pentanol, isoamyl alcohol and iso-octanol; the silicone oil is hydroxyl silicone oil and / or dimethicone.

[0020] Optionally, the ion collector is a mixture of quaternary ammonium and ether amine.

[0021] Optionally, the cationic collector is added in an amount of 100-500 g / t.

[0022] The present application has the following beneficial effects:

[0023] In the beneficiation stage of the siliceous-calcic collophanite, the present application first carries out reverse flotation under acidic conditions to remove magnesium, specifically using oxalic acid to adjust pH. Compared with the traditional phosphoric acid or sulfuric acid, on the one hand, the oxalic acid can be used to adjust the pH value of the ore slurry, on the other hand, C2O2-4and Ca2+and Mg2+and other inevitable ions generated by grinding and dissociation weaken their activation, in addition, it also avoids the introduction of PO3-4and SO2-4in the flotation system which affect the foam; the ore slurry obtained after reverse flotation to remove magnesium is mixed with activated carbon, which plays a role in removing the anionic collector adsorbed on the surface of the mineral particles in the reverse flotation process, avoiding the mutual influence of anions and cations in the reverse flotation process; and an antifoam agent is added, in which the higher carbon alcohol mainly plays a defoaming role, the higher carbon alcohol with good dispersibility diffuses to the surface of the foam and reacts with the active functional groups on the surface of the foam to change the stability of the foam, part of the molecules in the polyether can replace the active molecules in the flotation foam film to change the properties of the film, making it fragile, and the silicone oil derivative can reduce the surface tension of the gas bubble, the silicone oil has high wettability and is difficult to dissolve in water, and it is easy to form a thin film on the foam, which can hinder the interaction between molecules, thereby inhibiting the formation of foam; then neutral reverse flotation is carried out to remove silicon and aluminum, which can change the physicochemical properties of the foam surface and greatly reduce its half-life, solving the problems of large amount of flotation foam, large viscosity and poor flowability in the traditional double reverse flotation process. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The process flow chart of the present application. DETAILED DESCRIPTION

[0025] The embodiments of the present application will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only for illustration of the present application and should not be regarded as limiting the scope of the present application.

[0026] Example 1

[0027] The specific operation steps of the siliceous-calcic collophanite double reverse flotation method are as follows:

[0028] 1-1, After the phosphate ore is ground with recycled water, the phosphate ore is adjusted to a pH value of 4.8 with phosphoric acid and subjected to reverse flotation to remove magnesium, and the magnesium removal collector is XF-01, and the addition amount is 1.00 kg / t. The Ca2+ content in the magnesium removal concentrate filtrate obtained is 840 ppm, the Mg2+ content is 328 ppm, the PO3-4 content is 7881 ppm, and the SO2-4 content is 2110 ppm. Adjust the pH value to 7-7.5 with sodium carbonate, and then add 280 g / t of quaternary ammonium and ether amine (mass ratio 2:1) as collector for reverse flotation to remove aluminum and silicon. The flotation froth is fine and sticky, and the half-life is more than 30 minutes.

[0029] 1-2, The same process flow conditions as 1-1 are used, and oxalic acid is used instead of phosphoric acid. The Ca2+ content in the magnesium removal concentrate filtrate is reduced to 233 ppm, the Mg2+ content is 121 ppm, the PO3-4 content is 478 ppm, and the SO2-4 content is 80 ppm. The magnesium removal concentrate slurry is treated with 50 g / t of activated carbon powder to remove the drug, and the slurry concentration is diluted to 20% with recycled water. Adjust the pH value to 7-7.5 with sodium carbonate; mix polyglycerol, isoamyl alcohol and hydroxyl silicone oil in a mass ratio of 2:1:1 to prepare a 5% solution and add it to the slurry, and the amount is 70 g / t; then add quaternary ammonium and ether amine for reverse flotation to remove aluminum (same as 1-1). The aluminum removal froth is significantly increased, and the froth half-life is reduced to 4 minutes.

[0030] Example 2

[0031] 2-1, A certain siliceous-calcareous collophanite is subjected to a double reverse flotation process of flotation to remove magnesium first and then flotation to remove silicon and aluminum. Phosphoric acid is used as a pH adjuster in the magnesium removal stage, and the magnesium removal collector is XF-01, and the addition amount is 900 g / t. The magnesium removal concentrate filtrate obtained is adjusted to a pH value of 7.5 with sodium carbonate, and ether amine is used for reverse flotation to remove silicon and aluminum. After 50 cycles of reverse flotation magnesium removal operation, the Ca2+ content in the recycled water is 621 ppm, the Mg2+ content is 870 ppm, the PO3-4 content is 6456 ppm, and the SO2-4 content is 2477 ppm.

[0032] 2-2, Compared with 2-1, oxalic acid is used instead of phosphoric acid, and 60 g / t of activated carbon powder is added to remove the drug before desiliconization, and then sodium carbonate is used to adjust the pH value of the slurry to 7.5, and then ether amine is used for reverse flotation to remove silicon and aluminum. Compared with 2-1, the Ca2+ content in the recycled water is reduced to 115 ppm, the Mg2+ content is 96 ppm, the PO3-4 content is 279 ppm, and the SO2-4 content is 101 ppm.

[0033] 2-3, compared with 2-2, after adjusting the pH to 7.5, polyoxyethylene ether, polyethylene glycol, n-pentanol and dimethylsiloxane are mixed according to 2:1:1:1 to configure a 5% defoaming agent solution, which is added to the ore pulp for mixing, and the dosage is 50 g / t; finally, etheramine is added for desilication and dealumination. After using the defoaming agent, the amount of flotation froth is obviously reduced, the thickness of the flotation froth layer is reduced to 40% of the original, the froth half-life is reduced to 3 minutes, the flowability of the desilication and dealumination flotation froth is significantly improved, and the defoaming and defoaming effects of the mixed reagent are fully played.

[0034] Example 3

[0035] A self-made cylindrical foaming device is used for foaming test, the device has a diameter of 10 cm and a height of 60 cm, the mixing speed of the reagent is 300 rpm, and the air flow is 0.1 m3 / h.

[0036] 3-1, 500 ml of deionized water is added to the foaming device, and etheramine is added under the condition of a rotation speed of 300 rpm for sufficient stirring, and the addition amount is 2 g / 100 L, then air is blown for 2 minutes, the froth layer thickness is 39 cm, and the froth half-life is 65 minutes.

[0037] 3-2, under the same conditions as 3-1, after adding the same amount of etheramine, polyoxyethylene ether, isoamyl alcohol and hydroxy silicone oil are mixed and prepared for addition according to a ratio of 4:2:1, the addition amount is 0.8 g / 100 L, then air is blown for 2 minutes, the froth thickness is 17 cm, and the froth half-life is 7 minutes.

[0038] Example 4

[0039] A self-made cylindrical foaming device is used for foaming test, the device has a diameter of 10 cm and a height of 60 cm, the mixing speed of the reagent is 300 rpm, and the air flow is 0.1 m3 / h.

[0040] 4-1, 500 ml of a solution containing quaternary ammonium salt is added to the foaming device for foaming test, the dosage of the reagent is 2 g / 100 L, compressed air is introduced for 2 minutes, the froth layer thickness is 33 cm, and the froth half-life is 47 minutes.

[0041] 4-2, under the same conditions as 4-1, after adding etheramine, mixed defoaming reagent is continuously added to suppress the flotation froth, the defoaming agent is prepared by mixing polyoxyethylene ether, polyethylene glycol, n-pentanol and dimethylsiloxane according to a ratio of 2:2:2:3, and the dosage is 1.3 g / 100 L, the froth thickness is reduced to 12 cm, and the froth half-life is reduced to 4 minutes.

[0042] Example 5

[0043] 5-1, the double reverse flotation process of siliceous calcareous phosphate ore is first neutral condition desilication and then acid condition demagnesium, the pulp is adjusted by phosphoric acid in the demagnesium stage, the cationic collector remains good foamability under acid condition in the desilication and dealumination stage, the demagnesium flotation has abundant froth, stable froth property, long half-life and poor fluidity, and the desilication and dealumination effect is poor.

[0044] 5-2, the process flow is changed to first demagnesium and then desilication, oxalic acid is used to adjust the pulp acid-base in the demagnesium operation, 50g / t activated carbon powder is used to remove the reagent from the demagnesium concentrate pulp, sodium carbonate is used to adjust the pH value to 7, glycerol, isoamyl alcohol and hydroxyl silicone oil are mixed in a ratio of 2:1:1 to inhibit the desilication froth, and the dosage is 60g / t. Under the same cationic collector dosage, the desilication froth volume is significantly reduced, the rinse water can easily wash away the froth, the froth half-life is significantly shortened, and the process has strong continuity.

[0045] The above examples describe the preferred embodiments of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other way, and these simple modifications and combinations should also be considered as disclosed by the present application and belong to the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.

Claims

1. A method of improving the froth of a double-reverse flotation of a siliceous calcareous collophanite, characterized in that, The method comprises the following steps: S1, adjusting the pH of the phosphate ore slurry to be acidic by oxalic acid, adding a demagnesium collector to perform reverse flotation demagnesium, and obtaining a demagnesium concentrate slurry; S2, adding active carbon to the demagnesium concentrate slurry obtained in S1 and mixing, then diluting the slurry, adjusting the pH to 6.5-8, and adding a foam inhibitor and mixing; the foam inhibitor comprises a polyether compound, a higher carbon alcohol, and a silicone antifoam agent, wherein the polyether compound is polyoxyethylene ether, glycerol, and / or polyethylene glycol; the silicone is hydroxyl silicone and / or dimethicone; the foam inhibitor is prepared into a 5-15% solution, and the usage amount is 30-300 g / t; S3, adding a cationic collector to S2 to perform reverse flotation for removing aluminum and silicon, and obtaining a phosphate concentrate by solid-liquid separation of the reverse flotation slurry.

2. The method of claim 1, wherein: The P2O5 grade of the phosphate ore in the phosphate ore slurry is 20-30 wt%, the Al2O3 grade is 2.0-7.0 wt%, and the MgO grade is 1.0-5.0 wt%.

3. The method of claim 1, wherein: The concentration of the phosphate ore slurry in S1 is 30-35 wt%, and the pH is adjusted to 4-5 by oxalic acid.

4. The method of claim 1, wherein: The demagnesium collector in S1 is XF-01, and the addition amount is 0.5-2.5 kg / t.

5. The method of claim 1, wherein: The addition amount of the active carbon in S2 is 30-200 g / t, and the mixing time after addition is more than 10 min.

6. The method of claim 1, wherein: The water used for dilution in S2 is the water obtained after solid-liquid separation in S3, and the concentration of the slurry is diluted to 15-30 wt% after dilution; the pH is adjusted by sodium carbonate and / or sodium bicarbonate.

7. The method of claim 1, wherein: The higher carbon alcohol is n-butanol, n-pentanol, iso-pentanol, and iso-octanol.

8. The method of claim 1, wherein: The cationic collector is one of quaternary ammonium and ether amine or a mixture thereof in a certain proportion.

9. The method of claim 8, wherein: The addition amount of the cationic collector is 100-500 g / t.

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