Low-grade vanadium-titanium magnetite cooperative pre-separation process based on heavy medium separation

Abstract

This invention discloses a synergistic pre-separation process for low-grade vanadium-titanium magnetite based on heavy media separation, comprising the following steps: crushing the low-grade vanadium-titanium magnetite ore to obtain crushed ore; dry magnetic separation of the crushed ore to obtain coarse concentrate and coarse tailings; classifying the coarse tailings to obtain coarse-grained coarse tailings and fine-grained coarse tailings; heavy media separation of the coarse-grained coarse tailings to obtain heavy media separation concentrate and heavy media separation tailings; wet high-intensity magnetic separation of the fine-grained coarse tailings to obtain high-intensity magnetic separation concentrate and high-intensity magnetic separation tailings; merging the coarse concentrate, heavy media separation concentrate, and high-intensity magnetic separation concentrate into a pre-separation concentrate; and merging the heavy media separation tailings and high-intensity magnetic separation tailings into a pre-separation tailings. The pre-sorting process of this application can maximize the recovery rate of iron and titanium, while prioritizing the removal of a large amount of low-grade gangue before entering the mill, significantly improving the grade of the ore entering the mill in a shorter process, and reducing the energy consumption and cost of subsequent grinding and beneficiation operations.

Description

Technical Field

[0001] This invention relates to the field of mineral processing, specifically to a co-separation process for low-grade vanadium-titanium magnetite based on heavy media separation. Background Technology

[0002] Vanadium-titanium magnetite is a composite mineral resource containing iron, vanadium, and titanium. It is one of my country's strategic mineral resources and is widely used in national defense, metallurgy, chemical engineering, aerospace, electronics, and materials science. Vanadium-titanium magnetite is an important source of vanadium and titanium. Compared to other iron ore resources, vanadium-titanium magnetite has a higher comprehensive utilization value due to its content of multiple valuable metals. my country is rich in mineral resources, but most of its mineral resources are low-grade ores, while high-grade ores are scarce. In particular, high-grade iron ore suitable for blast furnace ironmaking has long relied on imports. Furthermore, after decades of development and utilization, the reserves of high-grade ores are decreasing. Currently, the prospective reserves of ultra-low-grade vanadium-titanium magnetite exceed 10 billion tons. Facing increasingly tense international and resource pressures, low-grade ores, complex and difficult-to-process ores, and refractory ores have become important reserve resources for my country's mineral resources. Therefore, the efficient development and utilization of low-grade vanadium-titanium magnetite is of significant strategic importance to my country's economic and national defense development.

[0003] Pre-sorting refers to the process of pre-enriching and removing some surrounding rock from the raw ore before grinding. As a crucial step in processing low-grade ores, ore pre-sorting has gained widespread attention with advancements in mineral processing technology and equipment. Pre-sorting achieves ore pre-enrichment by removing waste material, increasing the grade of the ore entering the mill, improving beneficiation efficiency, and significantly reducing the operating costs of subsequent processes. By pre-sorting the incoming raw ore, the feed rate to subsequent operations is reduced, thus lowering the workload of subsequent operations or increasing their efficiency. Common iron ore pre-sorting methods include high-intensity magnetic separation, low-intensity magnetic separation, and gravity separation. Currently, the industrial pre-sorting of vanadium-titanium magnetite primarily employs a multi-stage crushing-dry magnetic separation process. For example, Chinese patent document CN202410546488.1 discloses a staged crushing-pre-selection process for vanadium-titanium magnetite, which adopts a three-stage crushing-three-stage dry magnetic separation process to obtain iron concentrate with a TFe grade of 15.45% and pre-selected concentrate with a TiO2 grade of 5.84%. However, although the operation unit of this process is simple, the overall process is long and the energy consumption is also large due to the use of three-stage crushing dry magnetic tailings.

[0004] Traditional magnetic separation tailings disposal technology has a wide range of applications, high reliability, and significantly improved industrial application. Although the traditional tailings disposal process is now widely used, it still cannot hide its shortcomings of long process and unstable effect. In addition, rutile minerals often coexist in vanadium-titanium magnetite, and due to their extremely low specific magnetic susceptibility, they are difficult to enrich and recover in conventional titanium beneficiation processes, thus entering the tailings and causing titanium loss, which to some extent affects the pre-separation index of titanium.

[0005] In summary, there is an urgent need for a more stable and efficient new technology for low-grade vanadium-titanium magnetite to shorten the pre-selection process, improve the pre-sorting effect, and ensure the recovery rate of iron and titanium in low-grade vanadium-titanium magnetite. Summary of the Invention

[0006] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a co-pre-separation process for low-grade vanadium-titanium magnetite based on heavy media separation, so that it can be applied to complex and difficult-to-separate low-grade vanadium-titanium magnetite. Moreover, it can not only maximize the recovery rate of iron and titanium, but also pre-remove a large amount of low-grade gangue before entering the mill, and significantly improve the grade of the ore entering the mill in a shorter process, thereby reducing the energy consumption and cost of subsequent milling and beneficiation operations.

[0007] The objective of this invention is achieved through the following technical solution: A synergistic pre-separation process for low-grade vanadium-titanium magnetite based on heavy media separation includes the following steps: S1. The low-grade vanadium-titanium magnetite ore is crushed to obtain crushed ore; S2. The crushed ore is subjected to dry magnetic separation to obtain coarse concentrate and coarse tailings; S3. The coarse tailings are classified to obtain coarse-grained coarse tailings and fine-grained coarse tailings; S4. The coarse-grained tailings are subjected to heavy media separation to obtain heavy media separation concentrate and heavy media separation tailings; S5. The fine-grained coarse tailings are subjected to wet high-intensity magnetic separation to obtain high-intensity magnetic concentrate and high-intensity magnetic tailings; S6. Combine the coarse concentrate, the heavy medium separation concentrate and the strong magnetic separation concentrate into a pre-separated concentrate; S7. Combine the heavy medium separation tailings and the strong magnetic separation tailings into pre-separated tailings.

[0008] Specifically, in S1, the particle size of the crushed ore is less than 20 mm; Specifically, the specific steps of S1 include: crushing the low-grade vanadium-titanium magnetite ore and screening the crushed products. The undersize material from the screening process is used as the crushed ore; The oversize material from the sieve is returned to the crushing process for further crushing and sieving. This process is repeated until all crushed products have a particle size of less than 20 mm.

[0009] Specifically, in S2, the magnetic field strength of the dry magnetic separation is 4000~7000 Oe; Specifically, in S3, the coarse-grained tailings have a particle size greater than 1.0 mm; the fine-grained tailings have a particle size less than or equal to 1.0 mm. Preferably, in S4, the instrument used for heavy medium separation includes a heavy medium cyclone separator; Specifically, in S4, the heavy medium used for heavy medium separation includes a high-purity magnetic powder suspension. Specifically, the high-purity magnetic dielectric powder has a fineness of -325 mesh accounting for more than 85%; Specifically, the working density of the magnetic dielectric powder is 2.8~3.2 g / cm³; Specifically, the solid volume concentration of the magnetic dielectric powder is 25%~35%; Preferably, in S5, the magnetic field strength of the wet strong magnetic separation is 8000~12000 Oe; Specifically, the TFe grade in the low-grade vanadium-titanium magnetite ore is 12.0%~15.0%, and the TiO2 grade is 3.5%~5.5%.

[0010] Specifically, the low-grade vanadium-titanium magnetite ore is a complex and difficult-to-process low-grade vanadium-titanium magnetite, including gabbro-type vanadium-titanium magnetite with low grades of TFe and TiO2. It should be understood that titanomagnetite commonly exhibits varying degrees of sphenitization, chloritization, and biotitization, which affects the quality of iron concentrate. Furthermore, ilmenite is mainly found in granular form and exsolved platy form within titanomagnetite. The extremely fine-grained ilmenite platy crystals and rutile in titanomagnetite are difficult to effectively recover through beneficiation. The titanium in minerals such as titanomagnetite, sphene, and pyroxene is dispersed titanium, which is difficult to utilize, thus restricting the recovery and utilization of titanium in titanium concentrate.

[0011] The beneficial effects of this invention are: (1) This application discloses a co-concentration pre-separation process for low-grade vanadium-titanium magnetite based on heavy media separation. First, dry magnetic separation is used to efficiently separate minerals with strong magnetic properties. Then, heavy media separation and wet high-intensity magnetic separation are used to accurately recover valuable minerals from the coarse and fine tailings. This maximizes the recovery rate of iron and titanium while prioritizing the removal of a large amount of low-grade gangue before it enters the mill. This provides a new pre-enrichment pathway for the economical and efficient development of complex and difficult-to-separate low-grade vanadium-titanium magnetite, which can significantly improve the comprehensive utilization rate of this type of resource. It is of great significance for ensuring the security of my country's strategic mineral resources and reducing dependence on foreign sources.

[0012] (2) The present application discloses a co-process pre-separation process for low-grade vanadium-titanium magnetite based on heavy media separation. Through the co-process of "dry magnetic separation (coarse particles) - heavy media separation (coarse particles) - strong magnetic recovery (fine particles)," it covers key particle sizes from coarse to fine. It is universally applicable to vanadium-titanium magnetite with complex ore properties and uneven particle size distribution. It has a wide range of applications and good pre-enrichment effect.

[0013] (3) The low-grade vanadium-titanium magnetite co-pre-sorting process based on heavy media separation disclosed in this application can significantly improve the grade of the feed mill and reduce the feed amount. The entire process only uses one crushing, and the process is relatively short. It directly reduces the energy consumption of crushing and grinding, steel consumption and subsequent tailings treatment costs from the source. It conforms to the energy-saving concept of "more crushing and less grinding, and early disposal if possible", and has significant economic benefits.

[0014] (4) The low-grade vanadium-titanium magnetite co-pre-separation process based on heavy medium separation disclosed in this application uses mature and reliable unit technologies such as dry magnetic separation, heavy medium separation and wet strong magnetic separation. The process flow is smooth and easy to industrialize and control. Furthermore, by pre-discarding waste, the energy consumption and emissions of the entire process are reduced from the source. It is green and environmentally friendly and easy to promote and apply. Attached Figure Description

[0015] Figure 1 This disclosure provides a process flow diagram for the synergistic pre-sorting of low-grade vanadium-titanium magnetite based on heavy media separation. Detailed Implementation

[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0017] Example 1 This embodiment provides a co-sorting process for low-grade vanadium-titanium magnetite based on heavy medium separation. The vanadium-titanium magnetite has a TFe grade of 12.98% and a TiO2 grade of 3.72%. The quantitative results of its main minerals are shown in Table 1.

[0018] Table 1. Main mineral composition and content of the raw ore composite sample like Figure 1 As shown, the above pre-sorting process includes: S1. A jaw crusher is used to coarsely crush the vanadium-titanium magnetite ore (raw ore), followed by a first screening to obtain crushed ore with a particle size of -20.0 mm and first medium ore with a particle size of +20.0 mm; wherein, the first medium ore is returned to the crushing step; S2. The crushed ore is dry magnetically separated using an RCTS-5 dry permanent magnet drum separator to obtain coarse concentrate and coarse tailings. The magnetic field strength of the dry magnetic separation is 6000 Oe. S3. The coarse tailings are classified using a high-frequency vibrating screen to obtain coarse tailings with a particle size of +1.0 mm and fine tailings with a particle size of -1.0 mm. S4. A heavy medium hydrocyclone is used to perform heavy medium separation on coarse-grained tailings. The heavy medium separation concentrate and heavy medium separation tailings are produced. The heavy medium used in the heavy medium separation is a high-purity magnetic media powder suspension. The magnetic media powder has a fineness of -325 mesh (85%), a working density of 3.0 g / cm³, and a solid volume concentration of 30%. S5. A SLon 750 (1.5T) vertical ring pulsating high gradient magnetic separator was used to perform wet high-intensity magnetic separation on fine-grained coarse tailings to obtain high-intensity magnetic concentrate and high-intensity magnetic tailings. The magnetic field strength of the wet high-intensity magnetic separation was 10000 Oe. S6. The coarse concentrate, heavy media concentrate, and strong magnetic concentrate are combined into a pre-separated concentrate; S7. Heavy media separation tailings and strong magnetic separation tailings are combined into pre-separated tailings.

[0019] The results show that in the pre-sorting process of this embodiment, the yield of the pre-sorted concentrate is 42.41%, the grade of TFe is 23.41%, the recovery rate of TFe is 76.49%, the grade of TiO2 is 7.04%, and the recovery rate of TiO2 is 80.26%; the waste disposal rate is 57.59%, and the grade of TFe in the pre-sorted tailings is 5.30%, and the grade of TiO2 is 1.28%. Therefore, the pre-sorting process of this embodiment achieves the preliminary enrichment of iron and titanium in low-grade vanadium-titanium magnetite, removes waste rock in advance, reduces subsequent grinding costs and energy consumption, and improves the grade of the ore entering the beneficiation process.

[0020] Example 2 This embodiment provides a co-sorting process for low-grade vanadium-titanium magnetite based on heavy medium separation. The vanadium-titanium magnetite has a TFe grade of 14.06% and a TiO2 grade of 4.53%. The quantitative results of its main minerals are shown in Table 2.

[0021] Table 2. Main mineral composition and content of the raw ore composite sample like Figure 1 As shown, the above-mentioned mineral processing method includes: S1. A jaw crusher is used to coarsely crush the vanadium-titanium magnetite ore (raw ore), followed by a first screening to obtain crushed ore with a particle size of -20.0 mm and first medium ore with a particle size of +20.0 mm; wherein, the first medium ore is returned to the crushing step; S2. The crushed ore is dry magnetically separated using an RCTS-5 dry permanent magnet drum separator to obtain coarse concentrate and coarse tailings. The magnetic field strength of the dry magnetic separation is 5500 Oe. S3. The coarse tailings are classified using a high-frequency vibrating screen to obtain coarse tailings with a particle size of +1.0 mm and fine tailings with a particle size of -1.0 mm. S4. A heavy medium hydrocyclone is used to perform heavy medium separation on coarse-grained tailings. The heavy medium separation concentrate and heavy medium separation tailings are produced. The heavy medium used in the heavy medium separation is a high-purity magnetic media powder suspension. The magnetic media powder has a fineness of -325 mesh (85%), a working density of 3.2 g / cm³, and a solid volume concentration of 30%. S5. A SLon 750 (1.5T) vertical ring pulsating high gradient magnetic separator was used to perform wet high-intensity magnetic separation on fine-grained coarse tailings to obtain high-intensity magnetic concentrate and high-intensity magnetic tailings. The magnetic field strength of the wet high-intensity magnetic separation was 9000 Oe. S6. The coarse concentrate, heavy media concentrate, and strong magnetic concentrate are combined into a pre-separated concentrate; S7. Heavy media separation tailings and strong magnetic separation tailings are combined into pre-separated tailings.

[0022] The results show that in the pre-sorting process of this embodiment, the yield of the pre-sorted concentrate is 45.64%, the grade of TFe is 24.17%, the recovery rate of TFe is 78.46%, the grade of TiO2 is 8.22%, and the recovery rate of TiO2 is 82.82%; the waste disposal rate is 54.36%, and the grade of TFe in the pre-sorted tailings is 5.57%, and the grade of TiO2 is 1.43%. Therefore, the pre-sorting process of this embodiment achieves the preliminary enrichment of iron and titanium in low-grade vanadium-titanium magnetite, removes waste rock in advance, reduces subsequent grinding costs and energy consumption, and improves the grade of the ore entering the beneficiation process.

[0023] Comparative Example 1 Comparing Comparative Example 1 with Example 1; wherein, Comparative Example 1 uses the same raw ore as Example 1, and the difference between Comparative Example 1 and Example 1 is that: Comparative Example 1 uses the mineral processing method of Example 1 in Chinese Patent Document CN202410546488.1.

[0024] The results showed that the beneficiation method of Comparative Example 1 ultimately yielded a pre-separated concentrate with a yield of 37.68%, a TFe grade of 23.87%, a TFe recovery rate of 69.29%, a TiO2 grade of 7.39%, and a TiO2 recovery rate of 74.85%. This indicates that although the pre-separated concentrate product obtained by the beneficiation method of Comparative Example 1 is slightly of better quality than that of the beneficiation method of Comparative Example 1, the recovery effect of iron and titanium from the raw ore is significantly worse. Therefore, for the pre-separation of iron and titanium in complex and difficult-to-process low-grade vanadium-titanium magnetite, the beneficiation method of Example 1 can achieve better pre-separation results with a shorter process flow compared to the beneficiation method of Comparative Example 1.

[0025] Comparative Example 2 Comparing Comparative Example 2 with Example 2; wherein, Comparative Example 2 uses the same raw ore as Example 2, and the difference between Comparative Example 2 and Example 2 is that: Comparative Example 2 adopts the mineral processing method of Example 2 in Chinese Patent Document CN202210357102.3.

[0026] The results showed that the beneficiation method in Comparative Example 2 ultimately yielded a pre-separated concentrate with a yield of 46.64%, a TFe grade of 21.87%, a TFe recovery rate of 72.55%, a TiO2 grade of 7.39%, and a TiO2 recovery rate of 76.09%. This indicates that, compared to the beneficiation method in Example 1, the beneficiation method in Comparative Example 2 has a poorer recovery effect on iron and titanium in the raw ore, and the quality of the pre-separated concentrate product is lower. Therefore, for the pre-separation of iron and titanium in complex and difficult-to-process low-grade vanadium-titanium magnetite, the beneficiation method in Example 1 can achieve better pre-separation results with a shorter process flow compared to the beneficiation method in Comparative Example 1.

[0027] Comparative Example 3 Comparative Example 3 with Example 2; wherein, Comparative Example 3 uses the same raw ore as Example 2, and the difference between Comparative Example 3 and Example 2 is that: Comparative Example 3 uses the mineral processing method of Example 1 in Chinese Patent Document CN202411663492.2.

[0028] The results showed that the beneficiation method of Comparative Example 3 ultimately yielded a pre-separated concentrate with a yield of 46.64%, a TFe grade of 21.87%, a TFe recovery rate of 72.55%, a TiO2 grade of 7.39%, and a TiO2 recovery rate of 76.09%. This indicates that, compared to the beneficiation method of Example 1, the beneficiation method of Comparative Example 3 has a poorer recovery effect on iron and titanium in the raw ore, and the quality of the pre-separated concentrate product is lower. Therefore, for the pre-separation of iron and titanium in complex and difficult-to-process low-grade vanadium-titanium magnetite, the beneficiation method of Example 1 can achieve better pre-separation results with a shorter process flow compared to the beneficiation method of Comparative Example 1.

[0029] In summary, the co-processing pre-separation of low-grade vanadium-titanium magnetite based on heavy media separation provided in this disclosure is suitable for complex and difficult-to-separate low-grade vanadium-titanium magnetite. The pre-separation method provided in this disclosure is suitable for complex and difficult-to-separate low-grade vanadium-titanium magnetite, and at least achieves the following: it can not only maximize the recovery rate of iron and titanium, but also prioritize the removal of a large amount of low-grade gangue before entering the mill, and significantly improve the grade of the ore entering the mill in a shorter process, thereby reducing the energy consumption and cost of subsequent milling and beneficiation operations.

[0030] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A synergistic pre-sorting process for low-grade vanadium-titanium magnetite based on heavy media separation, characterized in that, Includes the following steps: S1. The low-grade vanadium-titanium magnetite ore is crushed to obtain crushed ore; S2. The crushed ore is subjected to dry magnetic separation to obtain coarse concentrate and coarse tailings; S3. The coarse tailings are classified to obtain coarse-grained coarse tailings and fine-grained coarse tailings; S4. The coarse-grained tailings are subjected to heavy media separation to obtain heavy media separation concentrate and heavy media separation tailings; S5. The fine-grained coarse tailings are subjected to wet high-intensity magnetic separation to obtain high-intensity magnetic concentrate and high-intensity magnetic tailings; S6. Combine the coarse concentrate, the heavy medium separation concentrate and the strong magnetic separation concentrate into a pre-separated concentrate; S7. Combine the heavy medium separation tailings and the strong magnetic separation tailings into pre-separated tailings.

2. The collaborative pre-sorting process according to claim 1, characterized in that, In S1, the particle size of the crushed ore is less than 20 mm; the crushing equipment includes a jaw crusher.

3. The collaborative pre-sorting process according to claim 1, characterized in that, The specific steps of S1 include: The low-grade vanadium-titanium magnetite ore is crushed, and the crushed products are screened. The undersize material from the screening process is used as the crushed ore; The oversize material from the sieve is returned to the crushing process for further crushing and sieving. This process is repeated until all crushed products have a particle size of less than 20 mm.

4. The collaborative pre-sorting process according to claim 1, characterized in that, In S2, the magnetic field strength of the dry magnetic separation is 4000~7000 Oe.

5. The collaborative pre-sorting process according to claim 1, characterized in that, In S3, the coarse-grained tailings have a particle size greater than 1.0 mm; The particle size of the fine-grained coarse-disposal tailings is less than or equal to 1.0 mm.

6. The collaborative pre-sorting process according to claim 1, characterized in that, In S4, the heavy medium separation uses an instrument including a heavy medium cyclone separator.

7. The collaborative pre-sorting process according to claim 1, characterized in that, In S4, the heavy medium used for heavy medium separation includes a high-purity magnetic powder suspension. The high-purity magnetic dielectric powder has a fineness of -325 mesh, accounting for more than 85%; The working density of the magnetic flux powder is 2.8~3.2 g / cm³; The solid volume concentration of the magnetic dielectric powder is 25%~35%.

8. The collaborative pre-sorting process according to claim 1, characterized in that, In S5, the magnetic field strength of the wet strong magnetic separation is 8000~12000 Oe.

9. The collaborative pre-sorting process according to claim 1, characterized in that, The low-grade vanadium-titanium magnetite ore has a TFe grade of 12.0%~15.0% and a TiO2 grade of 3.5%~5.5%.

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