Method for reinforced flotation separation of quartz sand with different fluid inclusion contents

Abstract

The invention provides a method for reinforced flotation separation of quartz sand with different fluid inclusion contents, and belongs to the field of mineral processing.The method for reinforced flotation separation of quartz sand with different fluid inclusion contents comprises the following steps that vein quartz is subjected to crushing, ore grinding and magnetic separation treatment, and magnetic concentrate is obtained; primary flotation is conducted on the magnetic concentrate to remove mica, and primary flotation concentrate is obtained; and primary flotation concentrate is placed in a flotation tank, the pH of the system is adjusted to be 3-4, potassium chloride is added, the mixture is stirred to be uniform, then a collecting agent is added, and secondary flotation separation is conducted. According to the method, the surface difference of quartz sand with different fluid inclusions is enhanced by controlling the content of the solution added with the potassium ions and the reaction time, the flotation separation enhancement of quartz particles with different fluid inclusions is realized, and particularly, the loss of the quartz sand without the fluid inclusions is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of mineral processing, and particularly relates to a method for enhancing flotation separation of quartz sand with different fluid inclusion contents. Background Art

[0002] High-purity quartz is widely used in industries such as photovoltaics, electronic information, and optical communication, and there is a huge demand in strategic emerging industries such as information technology, new energy, and new materials. Due to the scarcity of natural crystals, vein quartz and pegmatite have been widely studied as potential high-purity quartz raw materials. However, almost all high-purity quartz raw materials, whether vein quartz or pegmatite, contain fluid inclusions. Fluid inclusions in high-purity quartz sand will cause bubble defects and hydroxyl impurities in quartz products. When quartz sand melts at high temperature, the removal of fluid inclusions will form "pits" at their original positions, which causes air to enter the pits from the environment and form bubbles. Therefore, the fluid inclusion content in high-purity quartz sand needs to be as low as possible to ensure the quality of high-purity quartz materials / products. There have been many studies on methods for removing fluid inclusions. The most commonly used technique is the high-temperature explosion method, which mainly induces defects in quartz crystals at high temperature to provide channels and energy for the gasification and expansion of fluid inclusions. In addition, microwave heating technology has been widely used to assist in removing fluid inclusions by the high-temperature explosion method. However, these removal methods can only remove a small part of the fluid inclusions with larger particle sizes, and the fluid inclusions in quartz are usually less than 5 μm. Therefore, when there are many small fluid inclusions in quartz sand, the effect of traditional removal techniques is minimal.

[0003] Flotation is a commonly used method for separating and purifying minerals. Many researchers have demonstrated that flotation is an effective quartz beneficiation technique. Studies have shown that quartz can float in a dilute solution of hydrofluoric acid (HF) only with the help of a foaming agent. However, flotation is affected by many factors, such as the pH value of the pulp, the types of collector and activator, the dosage of collector and activator, time, and temperature. In addition, one of the most important factors affecting the flotation performance of minerals is the surface morphology, including roughness, roundness, contact angle, and shape, etc., and the other is the ion difference or the adsorption of specific ions on the mineral surface. Due to the formation of hydroxy complexes between metal ions and OH- in aqueous solutions under neutral or alkaline conditions, many scholars have studied the influence of metal ions on the flotation behavior of quartz under neutral and alkaline conditions and explained the action mechanism between metal ions, the quartz surface, and the reagents. However, under acidic conditions, it is difficult for metal ions to form hydroxy complexes, and whether metal ions will affect the flotation behavior of quartz and its influence mechanism are still unclear.

[0004] Research shows that some inevitable ions in the flotation solution come from fluid inclusions, and the components released by the inclusions have an impact on the flotation performance of minerals. It is mentioned in the published papers that using hydrofluoric acid (HF) as a regulator and anionic collector (AQY) and cationic collector (CQY) as a mixed collector can preliminarily achieve the separation of quartz sand particles with different fluid inclusion contents under acidic conditions. However, some quartz particles without fluid inclusions will be entrained in the flotation foam. Based on this, it is of great significance to further improve the flotation separation effect of quartz sand with different fluid inclusion contents. Summary of the Invention

[0005] In view of the technical problems existing in the background art, the present invention provides a method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, aiming to solve the technical problem of large losses of quartz sand without fluid inclusions when separating fluid inclusion-containing quartz sand by existing flotation methods.

[0006] In the first aspect, the present invention provides a method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, comprising the following steps: (1) Crushing and grinding vein quartz and then performing magnetic separation to obtain a magnetic separation concentrate; (2) Conducting primary flotation to remove mica from the magnetic separation concentrate to obtain a primary flotation concentrate; (3) Placing the primary flotation concentrate in a flotation cell, adjusting the pH of the system to 3 - 4, adding potassium chloride and stirring evenly, and then adding a collector for secondary flotation separation.

[0007] Preferably, the size of the vein quartz after crushing and grinding is in the -0.3 + 0.106 mm particle size range.

[0008] Preferably, the primary flotation to remove mica is specifically: adding sulfuric acid to adjust the pH of the system to 2 - 3, adding the flotation reagent dodecylamine for flotation, and the addition amount of dodecylamine is 100 - 150 g / t.

[0009] Preferably, the addition amount of potassium chloride is 200 - 350 mol / t.

[0010] Preferably, the stirring time of adding potassium chloride is 20 - 30 min.

[0011] Preferably, the collector includes an anionic collector and a cationic collector; the addition of the collector is specifically to add the anionic collector first and then the cationic collector.

[0012] Preferably, the total addition amount of the anionic collector and the cationic collector is 500 - 800 g / t.

[0013] Preferably, the mass ratio of the anionic collector to the cationic collector is 1:(3 - 5).

[0014] Preferably, the anionic collector includes sodium petroleum sulfonate.

[0015] Preferably, the cationic collector includes octadecylamine.

[0016] The principle of the technical solution of the present invention is as follows: Since the potassium ions released by the fluid inclusions themselves are less and adsorbed less on the surface of quartz, the selectivity of the reagent is poor, and the quartz without fluid inclusions is easily entrained and floated. The present invention enhances the surface difference of quartz sands with different fluid inclusions by controlling the content of the potassium ion solution added and the activation time. While ensuring the recovery rate of quartz sands with fluid inclusions, the possibility of quartz sands without fluid inclusions being entrained is significantly reduced, and the proportion and recovery rate of quartz sands without fluid inclusions in the flotation foam are both significantly reduced.

[0017] The results of the surface potential in the preliminary exploration experiments show that after adding potassium ions, the surface potential of quartz with a large amount of fluid inclusions moves in the positive direction, while the surface potential of quartz without fluid inclusions remains almost unchanged, indicating that potassium ions may be adsorbed on the surface of quartz with a large amount of fluid inclusions and affect its surface potential. When sodium petroleum sulfonate is adsorbed alone, compared with when no potassium ions are added, the surface potential of quartz with a large amount of fluid inclusions moves in the negative direction after adding potassium ions, indicating that the adsorption capacity of quartz with a large amount of fluid inclusions for sodium petroleum sulfonate is enhanced after adding potassium ions. When octadecylamine is adsorbed alone, after adding potassium ions, the surface potential of quartz without fluid inclusions changes significantly and moves in the negative direction (in the hydrofluoric acid system, the surface of quartz is etched by hydrofluoric acid to produce more hydroxyl groups), indicating that after adding potassium ions, the adsorption capacity of quartz without fluid inclusions for octadecylamine is reduced. After adsorbing the mixed collector of sodium petroleum sulfonate and octadecylamine, the surface potential difference between quartz without fluid inclusions and quartz with a large amount of fluid inclusions increases after adding potassium ions, indicating that adding potassium ions enhances the adsorption capacity of quartz with a large amount of fluid inclusions for sodium petroleum sulfonate and octadecylamine and weakens the adsorption capacity of quartz without fluid inclusions for sodium petroleum sulfonate and octadecylamine. The adsorption principle of potassium ions and the collector on the quartz surface is as Figure 1 shown.

[0018] The test results of the adsorption capacity of the reagent correspond to the surface potential results. Compared with the difference in the adsorption capacity without adding potassium ions, the difference in the adsorption capacity of quartz without fluid inclusions and quartz with fluid inclusions for the mixed solution of sodium petroleum sulfonate and octadecylamine changes significantly with the increase of potassium ion concentration and reaction time. After adding potassium ions, the adsorption capacity of quartz with fluid inclusions for the mixed solution of sodium petroleum sulfonate and octadecylamine first increases and then decreases, while the adsorption capacity of quartz without fluid inclusions for the mixed collector of sodium petroleum sulfonate and octadecylamine first decreases and then increases. Under the same dosage of the collector, compared with the situation without adding potassium ions, the recovery rate of quartz sand without fluid inclusions decreases significantly, while the recovery rate of quartz sand with fluid inclusions in flotation increases slightly.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: Based on the influence of the release of fluid inclusion components on the flotation behavior of quartz and the difference in the potassium ion adsorption ability between quartz with fluid inclusions and quartz particles without inclusions, by artificially controlling the addition amount of potassium ions and the reaction time, under the same dosage of flotation collector, the flotation separation of quartz particles with different fluid inclusion contents is strengthened, especially reducing the loss of quartz sand without fluid inclusions. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation decreases by 60% - 80% compared with that without adding ions, while the recovery rate of quartz sand particles with fluid inclusions increases by 45% - 60%. Thus, the subsequent complete removal of quartz with fluid inclusions can be achieved through multiple flotation, and the loss of quartz without fluid inclusions is greatly reduced. Description of the Drawings

[0020] Figure 1 The adsorption principle of potassium ions and the collector on the quartz surface in the present invention is as shown in the figure; Figure 2 It is the flow chart of the method for strengthening the flotation separation of quartz sand with different fluid inclusion contents in the present invention. Detailed Embodiments

[0021] Hereinafter, embodiments of the technical solution of the present invention will be described in detail with reference to the drawings. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, so they are only examples and cannot be used to limit the protection scope of the present invention.

[0022] To solve the technical problem of large losses of quartz sand without fluid inclusions during the existing flotation separation of quartz sand containing fluid inclusions, the present invention provides a method for enhancing the flotation separation of quartz sand with different fluid inclusion contents. Among them, by controlling the content of the potassium ion solution added and the reaction time, the surface difference of quartz sand with different fluid inclusions is enhanced, and while ensuring the recovery rate of quartz sand without fluid inclusions, the possibility of entrainment of quartz sand without fluid inclusions is significantly reduced.

[0023] In a first aspect, an embodiment of the present invention provides a method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, including the following steps: (1) Crushing and grinding vein quartz and performing magnetic separation to obtain a magnetic separation concentrate; (2) Performing primary flotation to remove mica from the magnetic separation concentrate to obtain a primary flotation concentrate; (3) Placing the primary flotation concentrate in a flotation cell, adjusting the pH of the system to 3-4, adding potassium chloride and stirring evenly, and then adding a collector for secondary flotation separation.

[0024] In the technical solution of the embodiment of the present invention, the primary flotation concentrate is placed in a flotation cell, and the pH of the system is adjusted to 3-4. This acidic environment helps to activate the surface of quartz. After adding potassium chloride, the selectivity of the flotation reagent is enhanced. Potassium ions enhance the adsorption ability of quartz with more fluid inclusions to the collector, and weaken the adsorption ability of quartz without fluid inclusions to the collector. Subsequently, a collector is added for secondary flotation. The collector can selectively adsorb on the surface of quartz with more inclusions, enhance its hydrophobicity, and make it easier to attach to the bubbles and float, thereby realizing the separation from quartz without fluid inclusions. This method realizes the enhancement of the flotation separation of quartz particles with different fluid inclusion contents, especially reducing the loss of quartz sand without fluid inclusions.

[0025] Preferably, the size of the vein quartz after crushing and grinding is in the -0.3 + 0.106 mm particle size range.

[0026] Preferably, the primary flotation to remove mica is specifically: adding sulfuric acid to adjust the pH of the system to 2-3, adding the flotation reagent dodecylamine for flotation, and the addition amount of dodecylamine is 100-150 g / t.

[0027] Preferably, the addition amount of potassium chloride is 200-350 mol / t.

[0028] In the technical solution of the embodiment of the present invention, if the potassium chloride addition amount is higher than 350 mol / t, there are too many potassium ions in the solution. It is inevitable that the quartz particles without fluid inclusions will adsorb potassium ions. When the collector is added again, there will be competitive adsorption of the reagent with the quartz with more fluid inclusions, resulting in a poor separation effect; if the potassium chloride addition amount is less than 200 mol / t, it will lead to a decrease in the floating particles, and at the same time, the selectivity of the reagent becomes poor, and the separation effect between the quartz particles with different fluid inclusions also becomes poor.

[0029] Preferably, the stirring time for adding potassium chloride is 20 - 30 min.

[0030] In the technical solution of the embodiment of the present invention, if the stirring time is less than 20 min, the quartz particles with fluid inclusions cannot stably adsorb potassium ions, and the surface potential and surface atomic coordination of the quartz without fluid inclusions have a small difference, and the collector cannot form characteristic adsorption, resulting in a poor separation effect; if the stirring time is higher than 30 min, it is inevitable that the quartz particles without fluid inclusions will adsorb potassium ions. When the collector is added again, there will be competitive adsorption of the reagent with the quartz with more fluid inclusions, resulting in a poor separation effect.

[0031] Preferably, the collector includes an anionic collector and a cationic collector; specifically, the anionic collector is added first and then the cationic collector is added.

[0032] Preferably, the total addition amount of the anionic collector and the cationic collector is 500 - 800 g / t.

[0033] Preferably, the mass ratio of the anionic collector to the cationic collector is 1:(3 - 5).

[0034] Preferably, the anionic collector includes sodium petroleum sulfonate.

[0035] Preferably, the cationic collector includes octadecylamine.

[0036] The following lists some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain the present invention and cannot be construed as a limitation to the present invention. For those not specified in the embodiments regarding specific technologies or conditions, they shall be carried out according to the technologies or conditions described in the literature in the art or according to the product specifications. For the reagents or instruments not specified with the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0037] I. Preparation method Example 1 A method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, the steps are as follows: (1) Crush and grind a certain vein quartz to make quartz sand with a particle size of -0.3 + 0.106 mm, and dry it for standby; (2) Conduct a magnetic separation operation on the quartz sand in step (1) to remove magnetic impurities such as iron-containing minerals and obtain magnetic separation concentrate; (3) Conduct a primary flotation on the magnetic separation concentrate in step (2) to remove mica. The mica flotation reagent is dodecylamine, with a dosage of 100 g / t. Use sulfuric acid to adjust the pH to 2.5. After the flotation is completed, collect the primary concentrate after removing mica; (4) Take 95 g of the primary concentrate obtained in step (3) and put it into a flotation cell. The flotation concentration is 35%. Add hydrofluoric acid to adjust the pH to 3. After stirring for 3 min, add potassium chloride solution with an addition amount of 200 mol / t and slowly stir at a speed of 1000 r / min for 20 min to obtain pulp; (5) Continuously add a collector to the pulp in step (4) for secondary flotation. The collectors used are sodium petroleum sulfonate and octadecylamine. The dosage of sodium petroleum sulfonate is 100 g / t, and the dosage of octadecylamine is 400 g / t. React for 3 min and scrape the foam for 3 min. Wash, filter, and dry the foam quartz after secondary flotation; (6) Uniformly sample the raw ore and the foam quartz after flotation, conduct professional detection and analysis of fluid inclusions, and calculate the recovery rate.

[0038] The results show that the recovery rate of quartz particles without fluid inclusions in the flotation foam quartz is 0.95%, and the recovery rate of quartz sand particles with fluid inclusions is 7.09%.

[0039] Example 2 A method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, the steps are as follows: (1) Crush and grind a certain vein quartz to make quartz sand with a particle size of -0.3 + 0.106 mm, dry it for standby; (2) Conduct a magnetic separation operation on the quartz sand in step (1) to remove magnetic impurities such as iron-containing minerals and obtain magnetic separation concentrate; (3) Conduct a primary flotation on the magnetic separation concentrate in step (2) to remove mica. The mica flotation reagent is dodecylamine, with a dosage of 150 g / t. Use sulfuric acid to adjust the pH to 2.5. After the flotation is completed, collect the primary concentrate after removing mica; (4) Take 95 g of the primary concentrate obtained in step (3) and put it into a flotation cell. The flotation concentration is 35%. Add hydrofluoric acid to adjust the pH to 3. After stirring for 3 min, add potassium chloride solution with an addition amount of 200 mol / t and slowly stir at a speed of 1000 r / min for 20 min to obtain pulp; (5) Continuing to add a collector to the pulp in step (4) for secondary flotation. The collectors used are sodium petroleum sulfonate and octadecylamine. The dosage of sodium petroleum sulfonate is 200 g / t, and the dosage of octadecylamine is 600 g / t. React for 3 min and skim the foam for 3 min. Wash, filter, and dry the froth quartz after secondary flotation; (6) Uniformly sampling the original ore and the froth quartz after flotation, conducting professional detection and analysis of fluid inclusions, and calculating the recovery rate.

[0040] The results show that the recovery rate of quartz particles without fluid inclusions in the flotation froth quartz is 1.33%, and the recovery rate of quartz sand particles with fluid inclusions is 6.58%.

[0041] Example 3 A method for enhancing the flotation separation of quartz sand with different fluid inclusion contents, the steps are as follows: (1) Crushing and grinding a certain vein quartz to make quartz sand with a particle size of -0.3 + 0.106 mm, and drying for standby; (2) Conducting a magnetic separation operation on the quartz sand in step (1) to remove magnetic impurities such as iron-containing minerals to obtain magnetic separation concentrate; (3) Conducting primary flotation on the magnetic separation concentrate in step (2) to remove mica. The mica flotation reagent is dodecylamine, and the reagent dosage is 150 g / t. Adjust the pH to 2.5 with sulfuric acid. After the flotation is completed, collect the primary concentrate after removing mica; (4) Take 95 g of the primary concentrate obtained in step (3) and put it into a flotation cell. The flotation concentration is 35%. Add hydrofluoric acid to adjust the pH to 3. After stirring for 3 min, add potassium chloride solution, and the addition amount is 350 mol / t. Slowly stir at a speed of 1000 r / min for 30 min to obtain pulp; (5) Continuing to add a collector to the pulp in step (4) for secondary flotation. The collectors used are sodium petroleum sulfonate and octadecylamine. The dosage of sodium petroleum sulfonate is 100 g / t, and the dosage of octadecylamine is 500 g / t. React for 3 min and skim the foam for 3 min. Wash, filter, and dry the froth quartz after secondary flotation; (6) Uniformly sampling the original ore and the froth quartz after flotation, conducting professional detection and analysis of fluid inclusions, and calculating the recovery rate.

[0042] The results show that the recovery rate of quartz particles without fluid inclusions in the flotation froth quartz is 1.09%, and the recovery rate of quartz sand particles with fluid inclusions is 6.72%.

[0043] Comparative Example 1 The difference between this comparative example and Example 1 is that potassium chloride is not added, that is, under the condition of pH=3, the dosage of sodium petroleum sulfonate is 100g / t, and the dosage of octadecylamine is 400g / t. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation is 4.04%, and the recovery rate of quartz sand particles containing fluid inclusions is 4.43%.

[0044] Comparative Example 2: The difference between this comparative example and Example 2 is that the amount of potassium chloride added is 550 mol / t, that is, under the condition of pH=3, the amount of sodium petroleum sulfonate reagent used is 200 g / t, and the amount of octadecylamine used is 600 g / t. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation is 2.23%, and the recovery rate of quartz sand particles containing fluid inclusions is 3.79%.

[0045] Comparative Example 3 The difference between this comparative example and Example 3 is that the amount of potassium chloride added is 100 mol / t, that is, under the condition of pH=3, the amount of sodium petroleum sulfonate agent used is 100 g / t, and the amount of octadecylamine used is 500 g / t. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation is 3.88%, and the recovery rate of quartz sand particles containing fluid inclusions is 5.05%.

[0046] Comparative Example 4 The difference between this comparative example and Example 3 is that the stirring time after adding potassium chloride is 3 minutes, that is, under the condition of pH=3, the dosage of sodium petroleum sulfonate is 100 g / t, and the dosage of octadecylamine is 500 g / t. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation is 0.80%, and the recovery rate of quartz sand particles containing fluid inclusions is 3.17%.

[0047] Comparative Example 5 The difference between this comparative example and Example 3 is that the stirring time after adding potassium chloride is 60 minutes, that is, under the condition of pH=3, the dosage of sodium petroleum sulfonate agent is 100 g / t, and the dosage of octadecylamine is 500 g / t. The recovery rate of quartz particles without fluid inclusions in the foam quartz obtained by flotation is 3.17%, and the recovery rate of quartz sand particles containing fluid inclusions is 4.05%.

[0048] It should be noted that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present invention are all included in the technical scope of the present invention. In addition, without departing from the scope of the main purpose of the present invention, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present invention.

Claims

1. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents, characterized in that, It includes the following steps: (1) Crushing, grinding and magnetic separation are carried out on vein quartz to obtain magnetic separation concentrate; (2) Conducting primary flotation to remove mica from the magnetic separation concentrate to obtain primary flotation concentrate; (3) Placing the primary flotation concentrate in a flotation cell, adjusting the pH of the system to 3-4, adding potassium chloride, stirring evenly, and then adding a collector for secondary flotation separation.

2. The method for strengthening flotation to separate quartz sand with different fluid inclusion contents according to claim 1, wherein The size of the vein quartz after crushing and grinding is in the -0.3+0.106mm particle size grade.

3. The method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 1, wherein The specific process of the primary flotation to remove mica is as follows: adding sulfuric acid to adjust the pH of the system to 2-3, adding the flotation reagent dodecylamine for flotation, and the addition amount of dodecylamine is 100-150g / t.

4. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 1, characterized in that, The addition amount of potassium chloride is 200-350mol / t.

5. A method for strengthening flotation to separate quartz sand with different fluid inclusion contents according to claim 1, characterized in that, The stirring time for adding potassium chloride and stirring is 20-30min.

6. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 1, characterized in that The collector includes an anionic collector and a cationic collector; the specific process of adding the collector is to add the anionic collector first and then the cationic collector.

7. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 6, characterized in that, The total addition amount of the anionic collector and the cationic collector is 500-800g / t.

8. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 7, characterized in that, The mass ratio of the anionic collector to the cationic collector is 1:(3-5).

9. A method for enhancing flotation to separate quartz sand with different fluid inclusion contents according to claim 8, characterized in that, The anionic collector includes sodium petroleum sulfonate.

10. A method for enhancing flotation separation of quartz sand with different fluid inclusion contents according to claim 8, characterized in that, The cationic collector includes octadecylamine.

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