A method of enhancing ilmenite flotation recovery

Abstract

The application discloses a method for strengthening ilmenite flotation recovery, and relates to the technical field of ilmenite flotation. A collector hydroxamic acid is added to the spiral classification sand return product, and then enters a grinding mill for grinding operation. The grinding product is subjected to flotation to obtain ilmenite concentrate and tailings. The hydroxamic acid is added to the sand return section of the spiral classifier. The circulation of the hydroxamic acid in the grinding mill can improve the grindability of the ore, increase the processing capacity of the grinding mill, and achieve the purpose of energy saving and consumption reduction. Compared with the existing method of adding the hydroxamic acid to the rear-end stirring barrel of the ball mill or directly adding the hydroxamic acid to the ball mill, the method increases the action time of the hydroxamic acid and the ilmenite, promotes the collection of the hydroxamic acid on the ilmenite, significantly increases the ilmenite flotation recovery rate, improves the resource utilization level, and can not add lead ions or reduce the lead ions, is friendly to the environment, and simplifies the production process.

Description

Technical Field

[0001] This invention relates to the field of ilmenite flotation technology, and more specifically to a method for enhancing the flotation and recovery of ilmenite. Background Technology

[0002] Ilmenite is the most important titanium-bearing mineral, providing over 90% of the world's titanium resources. Therefore, its efficient development and utilization are of great significance. Ilmenite, with the molecular formula FeTiO3, is weakly magnetic and has a high specific gravity. Therefore, it is typically recovered using magnetic separation and gravity separation methods. However, for fine-grained ilmenite ores, a combined flotation method is required for efficient recovery. Ilmenite flotation has always been a challenging and crucial issue in ilmenite beneficiation.

[0003] To obtain excellent flotation performance for ilmenite, it is typically necessary to finely grind the ilmenite to achieve monomer liberation, and use lead nitrate as an activator to promote its interaction with the collector hydroxamic acid / sodium oleate. Hydroxamic acid has the advantage of high selectivity and can chelate with metal atoms on the ilmenite surface, often used as a collector for ilmenite. However, to further increase the adsorption of hydroxamic acid on the ilmenite surface, lead nitrate is usually used to activate the ilmenite before adding the hydroxamic acid. However, lead nitrate is also a heavy metal ion, which is very harmful to the environment and the health of operators, failing to meet environmental protection requirements. Therefore, developing a green and environmentally friendly ilmenite activation method could significantly improve its flotation performance. Summary of the Invention

[0004] The purpose of this invention is to provide a method for enhancing the flotation and recovery of ilmenite, thereby alleviating the environmental hazards caused by the use of lead nitrate as an activator.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a method for enhancing the flotation recovery of ilmenite, characterized in that: the collector hydroxamic acid is added to the spiral classifier return sand section, and then enters the grinding mill for grinding operation, and the grinding product is subjected to flotation to obtain ilmenite concentrate and tailings.

[0006] A further technical solution is that the method includes the following steps:

[0007] (1) Prepare a solution of 5% to 10% by mass in a stirred tank using hydroxamic acid, an ilmenite collector;

[0008] (2) The ilmenite grinding product is fed into the spiral classifier for classification. The +0.074mm product is transported by the spiral to the sand outlet and discharged as return sand product to the grinding mill. The -0.074mm product is discharged from the overflow weir of the spiral classifier and enters the mixing tank. The hydroxamic acid solution prepared in (1) is added to the return sand section of the spiral classifier.

[0009] (3) Feed the returned sand product from (2) together with the fresh feed into the grinding mill, and control the grinding concentration to 50% to 70%. The product after grinding is introduced into a spiral classifier for classification.

[0010] (4) Introduce the overflow product from (2) into the mixing tank, stir for 2 minutes, and add No. 2 oil as a foaming agent. The amount of No. 2 oil is 50g / t, and the slurry concentration is adjusted to 30% to 35%.

[0011] (5) The slurry mixed in the mixing tank is introduced into the flotation machine for flotation to obtain ilmenite concentrate and tailings.

[0012] A further technical solution is that the grinding mill is a rod mill or a ball mill, and the grinding particle size is -0.074mm, accounting for ≥75%.

[0013] A further technical solution is that the amount of the collector hydroxamic acid solution added is 700-1200 g / t.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] (1) In this invention, hydroxamic acid is added to the return sand section of the spiral classifier. The circulation of hydroxamic acid in the grinding mill can improve the grindability of the ore, increase the processing capacity of the grinding mill, and achieve the purpose of energy saving and consumption reduction.

[0016] (2) The method described in this invention promotes the collection of ilmenite by hydroxamic acid, significantly increases the flotation recovery rate of ilmenite, and improves the level of resource utilization;

[0017] (3) Compared with the existing method of adding hydroxamic acid to the mixing tank at the back end of the ball mill or adding it directly to the ball mill, the method provided by the present invention adds hydroxamic acid to the return sand section of the spiral classifier, which prolongs the interaction time between hydroxamic acid and ilmenite and further enhances the interaction between the two. It eliminates the need to add heavy metal lead ions or reduces lead ions, which is environmentally friendly. Furthermore, the overflow product of the spiral classifier can be directly floated, which simplifies the production process and has broad application prospects. Attached Figure Description

[0018] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] Example 1

[0021] Using magnetic separation rough concentrate from an ilmenite beneficiation plant in Sichuan as the ore sample for this embodiment, the titanium dioxide content in the ore is 18.05%, and the gangue mineral closely associated with it is mainly pyroxene. The specific operation steps include the following:

[0022] (1) Prepare a 9% (w / w) solution of ilmenite collector hydroxamic acid in a stirred tank;

[0023] (2) The ilmenite grinding product is fed into the spiral classifier for classification. The +0.074mm product is transported by the spiral to the sand outlet and discharged as return sand product to the grinding mill. The -0.074mm product is discharged from the overflow weir of the spiral classifier and enters the mixing tank. The hydroxamic acid solution prepared in (1) is added to the return sand section of the spiral classifier. The amount of hydroxamic acid is 1200g / t.

[0024] (3) Feed the returned sand product from (2) together with the fresh ore into the grinding mill. The grinding concentration is 55%, the grinding fineness is 85% (-0.074mm), and the grinding mill is a ball mill. The grinding product is introduced into the spiral classifier according to the requirements in (2).

[0025] (4) Introduce the overflow product from (2) into the mixing tank, stir for 2 minutes, and add No. 2 oil as a foaming agent. The amount of No. 2 oil is 50g / t, and the slurry concentration is adjusted to 31%.

[0026] (5) The slurry mixed in the mixing tank is introduced into the flotation machine for flotation to obtain ilmenite concentrate and tailings.

[0027] The results of mineral processing tests for adding hydroxamic acid at the overflow and return sand sections of the spiral classifier are shown in Table 1.

[0028] Table 1

[0029]

[0030] As shown in Table 1, by adding hydroxamic acid at the return sand of the spiral classifier using the process flow of the present invention, the recovery rate and grade of titanium dioxide in ilmenite concentrate can be increased by 25.14% and 0.50%, respectively, compared with adding hydroxamic acid at the overflow.

[0031] Example 2

[0032] Using a weak magnetic separation-gravity separation rough concentrate from an ilmenite beneficiation plant in Yunnan as the ore sample for this example, the ore contains 25.64% titanium dioxide, and the gangue minerals closely associated with it are mainly quartz and calcite. The specific operation steps include the following:

[0033] (1) Prepare a 6.5% (w / w) solution of hydroxamic acid, the ilmenite collector, in a stirred tank;

[0034] (2) The ilmenite grinding product is fed into the spiral classifier for classification. The +0.074mm product is transported by the spiral to the sand outlet and discharged as return sand product to the grinding mill. The -0.074mm product is discharged from the overflow weir of the spiral classifier and enters the mixing tank. The hydroxamic acid solution prepared in (1) is added to the return sand section of the spiral classifier. The amount of hydroxamic acid is 700g / t.

[0035] (3) Feed the returned sand product from (2) together with the fresh ore into the grinding mill. The grinding concentration is 60%, the grinding fineness is 80% -0.074mm, and the grinding mill is a ball mill. The grinding product is introduced into the spiral classifier according to the requirements in (2).

[0036] (4) Introduce the overflow product from (2) into the mixing tank, stir for 2 minutes, and add No. 2 oil as a foaming agent. The amount of No. 2 oil is 50g / t, and the slurry concentration is adjusted to 34%.

[0037] (5) The slurry mixed in the mixing tank is introduced into the flotation machine for flotation to obtain ilmenite concentrate and tailings.

[0038] Table 2 shows the results of mineral processing tests when hydroxamic acid was added at the overflow and return sand sections of the spiral classifier.

[0039] Table 2

[0040]

[0041] As shown in Table 2, by adding hydroxamic acid at the return sand of the spiral classifier using the process flow of the present invention, the recovery rate and grade of titanium dioxide in ilmenite concentrate can be increased by 25.22% and 0.08%, respectively, compared with adding hydroxamic acid at the overflow.

[0042] Example 3

[0043] Using a gravity separation rough concentrate from an ilmenite beneficiation plant in Hainan as the ore sample for this example, the ore contains 24.07% titanium dioxide, and the gangue minerals closely associated with it are mainly quartz. The specific operational steps include the following:

[0044] (1) Prepare a 5% (w / w) solution of hydroxamic acid, the ilmenite collector, in a stirred tank;

[0045] (2) The ilmenite grinding product is fed into the spiral classifier for classification. The +0.074mm product is transported by the spiral to the sand outlet and discharged as return sand product to the grinding mill. The -0.074mm product is discharged from the overflow weir of the spiral classifier and enters the mixing tank. The hydroxamic acid solution prepared in (1) is added to the return sand section of the spiral classifier. The amount of hydroxamic acid is 750g / t.

[0046] (3) Feed the returned sand product from (2) together with the fresh ore into the grinding mill. The grinding concentration is 67%, the grinding fineness is 78% (-0.074mm), and the grinding mill is a rod mill. The grinding product is introduced into the spiral classifier according to the requirements in (2).

[0047] (4) Introduce the overflow product from (2) into the mixing tank, stir for 2 minutes, and add No. 2 oil as a foaming agent. The amount of No. 2 oil is 50g / t, and the slurry concentration is adjusted to 35%.

[0048] (5) The slurry mixed in the mixing tank is introduced into the flotation machine for flotation to obtain ilmenite concentrate and tailings.

[0049] The results of mineral processing tests for adding hydroxamic acid at the overflow and return sand sections of the spiral classifier are shown in Table 3.

[0050] Table 3

[0051]

[0052] As shown in Table 3, by adding hydroxamic acid at the return sand of the spiral classifier using the process flow of the present invention, the recovery rate and grade of titanium dioxide in ilmenite concentrate can be increased by 25.61% and 0.38%, respectively, compared with adding hydroxamic acid at the overflow.

[0053] The above description represents the preferred embodiments of the present invention. For those skilled in the art, any equivalent transformations or structural improvements made based on the description and drawings of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method of enhancing the flotation recovery of ilmenite, characterised by: The collector hydroxamic acid is added to the spiral classification sand return section, and then introduced into the grinding mill for grinding operation, and the grinding product is subjected to flotation to obtain ilmenite concentrate and tailings; the mass concentration of the collector hydroxamic acid is 5% to 10%, and the addition amount is 700 to 1200 g / t; no activator heavy metal lead ion is added in the flotation process; The addition to the spiral classification sand return section is specifically as follows: the ilmenite grinding product is introduced into the spiral classifier for classification operation, the product is conveyed by the spiral to the sand sink to be discharged as a sand return product and returned to the grinding mill, and the product is discharged from the overflow weir of the spiral classifier to enter the stirring barrel, and the collector hydroxamic acid is added to the sand return section of the spiral classifier; When entering the grinding mill for grinding operation, the sand return product is introduced into the grinding mill together with fresh feed.

2. A method of enhanced flotation recovery of ilmenite according to claim 1 characterised in that: The method comprises the following steps: Step (1): the ilmenite collector hydroxamic acid is prepared into a solution with a mass concentration of 5% to 10% in the stirring barrel; Step (2): the ilmenite grinding product is introduced into the spiral classifier for classification operation, the +0.074 mm product is conveyed by the spiral to the sand sink to be discharged as a sand return product and returned to the grinding mill, and the -0.074 mm product is discharged from the overflow weir of the spiral classifier to enter the stirring barrel, and the hydroxamic acid solution prepared in step (1) is added to the sand return section of the spiral classifier; Step (3): the sand return product in step (2) is introduced into the grinding mill together with fresh feed, the grinding concentration is controlled to be 50% to 70%, and the product after grinding is introduced into the spiral classifier for classification; Step (4): the overflow product in step (2) is introduced into the stirring barrel, the stirring time is 2 min, the No. 2 oil is added as a foaming agent, and the pulp concentration is adjusted to 30% to 35%; Step (5): the mixed pulp in the stirring barrel is introduced into the flotation machine for flotation to obtain ilmenite concentrate and tailings.

3. A method of enhanced flotation recovery of ilmenite according to claim 1 characterised in that: The grinding mill is a rod mill and a ball mill, and the grinding particle size is -0.074 mm, accounting for ≥75%.

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