A silicate gangue entrainment-controlled flotation reagent and its flotation method

Abstract

This invention discloses a flotation reagent for controlling the entrainment of silicate gangue and its flotation method, belonging to the field of mineral separation technology. It solves the problem that existing flotation reagents cannot overcome the severe gangue entrainment caused by the small particle size of gangue in lean and difficult-to-process ores. The silicate gangue entrainment-controlling flotation reagent of this invention includes a silanoxy-modified hyperbranched polymer; the silanoxy-modified hyperbranched polymer is synthesized from hydrophilic organic macromolecules, silane coupling agents, and chemical auxiliaries. This invention, through the silanoxy-modified hyperbranched polymer, can effectively reduce gangue entrainment, lower concentrate ash content, and improve concentrate grade, which is of great significance for the efficient flotation of lean and difficult-to-process ores.

Description

Technical Field

[0001] This invention relates to the field of mineral sorting technology, and in particular to a silicate gangue entrainment control flotation reagent and its flotation method. Background Technology

[0002] my country is one of the world's most resource-rich countries, possessing abundant mineral resources. In the process of mineral resource development and utilization, as rich ores are gradually depleted, developers need to shift towards mining lean, complex, and difficult-to-process ores to meet industrial and economic demands. However, lean, complex, and difficult-to-process ores are typically characterized by fine and complex mineral composition and low comprehensive utilization. To achieve effective mineral recovery, the flotation process often requires fine grinding to achieve effective mineral liberation. Lean, complex, and difficult-to-process ores mainly contain silicate gangue such as quartz, kaolinite, and chlorite. Fine grinding produces fine-grained slime, which deteriorates the flotation environment, leading to technical problems such as decreased concentrate grade and substandard quality. For the separation of lean, complex, and difficult-to-process ores, entrainment is the main mechanism leading to a decrease in concentrate grade. Due to their small particle size and poor settling effect, fine-grained gangue minerals are easily carried into the concentrate by the water flow during the separation process, affecting concentrate quality. Therefore, developing a flotation reagent to control entrainment in silicate gangue is extremely important.

[0003] Currently, organic macromolecular flotation reagents are generally used to improve the flotation effect of lean, complex, and difficult-to-process ores. Traditional organic macromolecules usually have hydrophilic properties and also have flocculation effects. Due to their thickening effect and severe entrainment, they still have shortcomings such as poor reagent selectivity and poor flotation selectivity when separating lean, complex, and difficult-to-process ores. They cannot overcome the problem of severe gangue entrainment caused by small gangue particle size, which seriously affects the quality of concentrate. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a silicate gangue entrainment control flotation reagent and its flotation method, in order to solve the problem that existing flotation reagents cannot overcome the serious gangue entrainment caused by the small particle size of gangue in lean and difficult-to-process ores.

[0005] The objective of this invention is mainly achieved through the following technical solutions:

[0006] On the one hand, the present invention provides a flotation reagent for entrainment control of silicate gangue, including a silanoxy-modified hyperbranched polymer;

[0007] Silaneoxy-modified hyperbranched polymers are synthesized from hydrophilic organic macromolecules, silane coupling agents, and chemical auxiliaries.

[0008] In one possible design, the hydrophilic organic macromolecule is one of vinyl polymers, polyamides, or polyesters.

[0009] In one possible design, the silane coupling agent is an organosilicon compound containing two groups with different chemical properties, and its structural formula is: YR-SiX3;

[0010] Wherein, YR is a non-hydrolyzable group, and X3 is a hydrolyzable group; Y is one of vinyl, amino, epoxy, or azide groups; R is (CH2). n n = 0-3, R is used to connect Y to Si atoms; X is a group that can undergo hydrolysis to generate Si-OH.

[0011] On the other hand, the present invention also provides a flotation method for silicate gangues, using the above-mentioned flotation reagents, the flotation method comprising:

[0012] Step 1: Pour the slurry into the aerated flotation mixing tank and turn on the mechanical stirring device to disperse the slurry evenly.

[0013] Step 2: Add a multivalent metal ion pH adjuster to the slurry to adjust the pH value of the slurry;

[0014] Step 3: Add silaneoxy-modified hyperbranched polymer to the slurry and stir;

[0015] Step 4: Add the collector to the slurry and stir;

[0016] Step 5: Add foaming agent to the slurry and stir;

[0017] Step 6: Add water to the slurry to the set level, then connect the air pump power supply and open the air valve to start filling the slurry with air;

[0018] Step 7: After inflating for 10 seconds, start scraping the bubbles and collecting the concentrate and tailings products;

[0019] Step 8: Turn off the mechanical stirring device and the air valve;

[0020] Step 9: Process the obtained concentrate and tailings and analyze the obtained data.

[0021] Furthermore, in step 1, the mass concentration of the slurry is 40-60 g / L.

[0022] Furthermore, in step 1, the stirring speed of the mechanical stirring device is 1200-1600 rpm.

[0023] Furthermore, in step 2, the multivalent metal ion pH adjuster is limestone or sodium carbonate.

[0024] Furthermore, in step 2, the pH of the slurry is adjusted to 9.0-9.5 after being treated with a pH adjuster.

[0025] Furthermore, in step 4, the collector is kerosene.

[0026] Furthermore, in step 5, the foaming agent is 2-octanol.

[0027] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0028] (1) In this invention, silaneoxy-modified hyperbranched polymers react with fine silicate gangue minerals dispersed in the slurry during flotation to form polymer-silicate gangue mineral flocs, thereby avoiding the inclusion of fine silicate gangue minerals into the clean coal during flotation and affecting the quality of the clean coal.

[0029] (2) This invention solves the problem of fine silicate gangue mineral inclusions in the flotation process by modifying hyperbranched polymers with silaneoxy groups, thereby strengthening the flotation process, improving product quality, and thus increasing enterprise benefits.

[0030] (3) The present invention can effectively reduce gangue inclusions, reduce concentrate ash content and improve concentrate grade by modifying hyperbranched polymers with silaneoxy groups. This is of great significance for efficient flotation of lean and difficult-to-process ores.

[0031] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0032] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0033] Figure 1 This is a schematic diagram of the flotation process in Embodiment 1 of the present invention. Detailed Implementation

[0034] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0035] On one hand, this invention provides a flotation reagent for regulating the entrainment behavior of silicate gangues, comprising a silanoxy-modified hyperbranched polymer. The silanoxy-modified hyperbranched polymer is a macromolecule synthesized under certain chemical conditions using a hydrophilic organic macromolecule and a silane coupling agent. The preparation process of the silanoxy-modified hyperbranched polymer includes:

[0036] S1. Weigh 0.1g of hydrophilic organic macromolecule and 0.1g of silane coupling agent, and transfer them to a 250ml beaker;

[0037] S2. Add 100ml of methanol to the beaker, and add pH adjuster NaHCO3 to adjust the pH to 7.5;

[0038] S3. Turn on the thermostatic magnetic stirrer and set the temperature to 70°C. Place the beaker on the thermostatic magnetic stirrer and stir for at least 3.5 hours to allow the hydrophilic organic macromolecules to fully react with the silane coupling agent. After the reaction is complete, the silaneoxy-modified hyperbranched polymer is obtained.

[0039] Compared with traditional organic macromolecular flotation reagents, the silanoxy-modified hyperbranched polymer provided by this invention can selectively and efficiently react with the silanol groups on the surface of silicate gangue minerals to form a stable flocculent structure. While promoting the sedimentation of fine-grained gangue minerals, it also enhances the hydrophilicity of gangue mineral particles, thus achieving targeted regulation of the entrainment behavior of silicate gangue minerals.

[0040] The aforementioned hydrophilic organic macromolecule is one of vinyl polymers, polyamides, and polyesters. This hydrophilic organic macromolecule is used to improve the hydrophilicity of the surface of silicate gangue minerals, prevent the silicate gangue minerals from undergoing hydrophobic modification under the action of collectors and foaming agents, ensure that the silicate gangue does not adhere to the air bubbles, and thus allow it to remain in the slurry and become tailings for discharge.

[0041] The aforementioned silane coupling agent is an organosilicon compound with a special structure containing two groups with different chemical properties, and its structural formula is: YR-SiX3. Wherein: YR is a non-hydrolyzable group, and X3 consists of three hydrolyzable groups; Y is a group capable of reacting with organic macromolecules, for example, Y is one of vinyl, amino, epoxy, or azide groups; R is a short-chain alkane group with the structural formula (CH2)n, where n = 0-3, and R is used to connect Y to Si atoms; X can undergo hydrolysis to generate Si-OH groups. This silane coupling agent contains three hydrolyzable groups.

[0042] It should be noted that the aforementioned chemical auxiliaries, such as methanol, are used as solvents to create an anhydrous environment. When the hydrophilic organic macromolecules react chemically with the silane coupling agents, the non-hydrolyzable groups on the silane coupling agents undergo a synthetic reaction with the hydrophilic organic macromolecules. Different hydrophilic silane coupling agents are used to end-cap and modify the active groups of the hydrophilic organic macromolecules, forming silanoxy-modified hyperbranched polymers.

[0043] The formation process of silanoxy-modified hyperbranched polymers is as follows:

[0044]

[0045] Wherein, Y is one of vinyl, amino, epoxy, or azide groups; R is a short-chain alkane group, such as -CH2, -CH2-CH2, or -(CH2)3, used to connect Y to Si atoms; X is a hydrolyzable group, which hydrolyzes to generate Si-OH, and this silane coupling agent contains three hydrolyzable groups; -A- is a hydrophilic macromolecule, and n in (-A-)n represents the number of hydrophilic macromolecules, indicating that there are many -A- groups, and n is uncountable.

[0046] The branching hydrolysis process of silanoxy-modified hyperbranched polymers is as follows:

[0047]

[0048] Wherein, Y is one of vinyl, amino, epoxy, or azide groups; R is a short-chain alkane group, such as -CH2, -CH2-CH2, or -(CH2)3, used to connect Y to Si atoms; X is a hydrolyzable group, which hydrolyzes to generate Si-OH; n is uncountable.

[0049] Under alkaline conditions, the hydrolyzable groups on the silanoxy modified hyperbranched polymer undergo hydrolysis. After hydrolysis, they can undergo hydroxyl dehydration condensation reaction with the hydroxyl groups of Si-OH and Al-OH on the surface of silicate gangue minerals and generate hydrogen bonds to form polymer-silicate gangue mineral flocs. The polymer-silicate gangue mineral flocs remain at the bottom of the coal slurry and become tailings.

[0050] It should be noted that the specific reaction process of the above-mentioned hydroxyl dehydration condensation reaction is as follows:

[0051]

[0052] The specific reaction process for generating hydrogen bonds described above is as follows:

[0053]

[0054] It should be noted that the aforementioned hydrophilic organic macromolecules can enhance the hydrophilicity of silicate gangue minerals, thereby strengthening the hydrophilicity of the polymer-silicate gangue mineral flocs formed by the silicate gangue minerals and silane coupling agents. Furthermore, the particle size of the formed polymer-silicate gangue mineral flocs is much larger than the original particle size of the silicate gangue minerals. Both the increased hydrophilicity of the silicate gangue minerals and the increased particle size of the polymer-silicate gangue mineral flocs promote the sedimentation of silicate gangue mineral particles in the slurry, thus effectively reducing the entrainment of silicate gangue.

[0055] It should be noted that, in order to avoid structural instability of polymer-silicate gangue mineral flocs under stirring, the present invention selects a suitable flow field environment during the flotation process. A suitable process environment can both disperse the target mineral particles in the water and avoid structural breakage and dispersion of the aforementioned polymer-silicate gangue mineral flocs.

[0056] On the other hand, the present invention also provides a flotation method for silicate gangues, using the above-mentioned silicate gangue entrainment-controlled flotation reagent, the flotation method comprising the following steps:

[0057] Step 1: Pour the slurry with a mass concentration of 40-60 g / L into the aerated flotation mixing tank, turn on the mechanical agitator, set the speed between 1200-1600 rpm to create a suitable flow field environment, and stir and adjust the slurry for 2 minutes to make the slurry evenly dispersed.

[0058] Step 2: Add a multivalent metal ion pH adjuster, such as limestone or sodium carbonate, and strictly control the pulp pH to 9.0-9.5;

[0059] It should be noted that in step 2 above, the pH of the pulp is strictly controlled and it is kept weakly alkaline. The purpose of this is to provide a suitable flotation environment for the reaction between the silanoxy modified hyperbranched polymer and the silicate gangue minerals in the subsequent flotation process, and at the same time, it plays a role in coordination-assisted formation of polymer-silicate gangue mineral flocs.

[0060] Step 3: Add silanoxy-modified hyperbranched polymer and stir the slurry at 1200-1600 rpm for 2 minutes to allow it to react with the silicate gangue minerals in the slurry and form polymer-silicate gangue mineral flocs.

[0061] Step 4: Add the collector and stir for 1 minute to change the hydrophobicity of the target mineral surface and improve its floatability;

[0062] Step 5: Add foaming agent and stir for 30 seconds to reduce the surface tension of water and form stable foam;

[0063] Step 6: Add an appropriate amount of water to the flotation cell to reach the suitable liquid level, which will facilitate subsequent flotation skimming. After adding water and stirring for 10 seconds, start aeration, controlling the aeration volume to 0.1-0.3 m³. 3 / (m 2 Between ·min), connect the air pump power supply and open the air valve to generate bubbles in the slurry. This allows the hydrophobic particles to adhere to the bubbles and rise with them to the foam layer, where they are discharged as concentrate. Meanwhile, the hydrophilic particles remain in the slurry and are discharged as tailings.

[0064] Step 7: After inflating for 10 seconds, start scraping the bubbles and collecting the concentrate and tailings products;

[0065] Step 8: Turn off the mechanical stirring device and the air valve;

[0066] Step 9: Process the obtained concentrate and tailings and analyze the obtained data.

[0067] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0068] Compared to traditional flotation methods for lean and difficult-to-process ores, this invention uses silane-modified hyperbranched polymers as modifiers. These polymers react with silicate gangue minerals to form stable polymer-silicate gangue mineral flocs, promoting the settling of silicate gangue particles, reducing gangue entrainment, and enhancing flotation selectivity.

[0069] Example 1

[0070] In a specific embodiment of the present invention, the above-mentioned silicate gangue entrainment-controlled flotation reagent and flotation method are used to separate the new Julong coal sample. The specific separation flowchart is as follows. Figure 1 As shown. The specific steps include:

[0071] Step 1: Add coal slurry with a mass concentration of 58 g / L to the flotation cell, turn on the mechanical agitator, and stir and adjust the slurry at 1500 rpm for 2 minutes to make the coal slurry evenly dispersed in the water.

[0072] Step 2: Add limestone as a pH adjuster and stir for 1 minute to make the pulp pH 9.1, providing a suitable flotation environment for subsequent reactions;

[0073] Step 3: Add silanoxy-modified hyperbranched polymer, stir the slurry for 2 minutes to allow the flotation reagent to react with the silicate gangue minerals and form polymer-silicate gangue mineral flocs;

[0074] Step 4: Add the collector kerosene and stir for 1 minute to change the hydrophobicity of the coal particle surface and improve the buoyancy of the coal particles;

[0075] Step 5: Add the foaming agent 2-octanol and stir for 30 seconds to reduce the surface tension of water and form foam;

[0076] Step 6: Inflate the air pump. Connect the power supply and open the inflation valve. Inflate to 0.2m³. 3 / (m 2 ·min);

[0077] Step 7: After inflating for 10 seconds, start scraping the bubbles. Set the scraping time to 3 minutes.

[0078] Step 8: Turn off the mechanical stirring device and the air valve;

[0079] Step 9: Filter, dry, and burn the obtained clean coal and tailings, and perform data analysis.

[0080] The yield and ash content of the clean coal and tailings obtained in Example 1 are shown in Table 1 below:

[0081] Table 1. Flotation reagent dosage and flotation results

[0082]

[0083] As can be seen from the table of Example 1 above, the ash content of clean coal decreases with the increase of the amount of silaneoxy-modified hyperbranched polymer added. When the amount of silaneoxy-modified hyperbranched polymer is 200 g / t, the yield of clean coal is 62.76% and the ash content of clean coal is 7.56%. This shows that silaneoxy-modified hyperbranched polymer can effectively reduce the inclusion of silicate gangue minerals during flotation and improve the quality of clean coal.

[0084] It should also be noted that, compared to the test without adding flotation modifiers, i.e., the amount of silaneoxy-modified hyperbranched polymer added was 0 g / t, the ash content of the clean coal decreased from 12.07% to 7.56% after adding the modifier silaneoxy-modified hyperbranched polymer.

[0085] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A silicate gangue entrainment-controlled flotation reagent, characterized in that, Including silane-oxygen-modified hyperbranched polymers; The silanoxy-modified hyperbranched polymer is synthesized from hydrophilic organic macromolecules, silane coupling agents, and chemical auxiliaries. The hydrophilic organic macromolecule is one of vinyl polymers, polyamides, and polyesters; The silane coupling agent is an organosilicon compound containing two groups with different chemical properties, and its structural formula is: YR-SiX3; Wherein, YR is a non-hydrolyzable group, and X3 consists of three hydrolyzable groups; Y is one of vinyl, amino, epoxy, or azide groups; and R is (CH2). n n=0-3, R is used to connect Y to Si atoms; X is a group that can undergo hydrolysis to generate Si-OH.

2. A flotation method for silicate gangue, characterized in that, The flotation method using the flotation reagent of claim 1 includes: Step 1: Pour the slurry into the aerated flotation mixing tank and turn on the mechanical stirring device to disperse the slurry evenly. Step 2: Add a multivalent metal ion pH adjuster to the slurry to adjust the pH value of the slurry; Step 3: Add silaneoxy-modified hyperbranched polymer to the slurry and stir; Step 4: Add the collector to the slurry and stir; Step 5: Add foaming agent to the slurry and stir; Step 6: Add water to the slurry to the set level, then connect the air pump power supply and open the air valve to start filling the slurry with air; Step 7: After inflating for 10 seconds, start scraping the bubbles and collecting the concentrate and tailings products; Step 8: Turn off the mechanical stirring device and the air valve; Step 9: Process the obtained concentrate and tailings and analyze the obtained data.

3. The flotation method for silicate gangue according to claim 2, characterized in that, In step 1, the mass concentration of the slurry is 40-60 g / L.

4. The flotation method for silicate gangue according to claim 2, characterized in that, In step 1, the stirring speed of the mechanical stirring device is 1200-1600 rpm.

5. The flotation method for silicate gangue according to claim 2, characterized in that, In step 2, the multivalent metal ion pH adjuster is limestone or sodium carbonate.

6. The flotation method for silicate gangue according to claim 2, characterized in that, In step 2, the pH of the slurry is adjusted to 9.0-9.5 by a pH adjuster.

7. The flotation method for silicate gangue according to claim 2, characterized in that, In step 4, the collector is kerosene.

8. The flotation method for silicate gangue according to claim 2, characterized in that, In step 5, the foaming agent is 2-octanol.

Images