Beneficiation method for reducing overgrinding of ilmenite

Abstract

This invention relates to a beneficiation method for reducing over-grinding of ilmenite. The steps are as follows: The coarse-grained portion of the iron ore tailings after classification is subjected to multi-stage spiral gravity separation to classify the ilmenite according to its intergrowth type, yielding spiral concentrate, middlings, and tailings. The middlings are used as the first grinding feed. The spiral concentrate is further coarsened to classify the ilmenite according to its intergrowth type a second time, yielding oversize and undersize, with the oversize used as the second grinding feed. The undersize is subjected to wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation to classify the ilmenite according to its intergrowth type a third time, yielding titanium concentrate and corresponding tailings. The corresponding tailings are used as the third grinding feed. After mixing and grinding the three grinding feeds, when the TiO2 grade of the product is less than 10%, it enters a first-stage fine iron removal process; when the TiO2 grade of the product is greater than 10%, it enters a second-stage fine iron removal process. This invention improves the recovery rate of ilmenite, reduces grinding costs, and increases the economic benefits for enterprises.

Description

Technical Field

[0001] This invention belongs to the field of ilmenite beneficiation technology, and particularly relates to beneficiation technology for reducing over-grinding of ilmenite in vanadium-titanium magnetite tailings, and more specifically, to a beneficiation method for reducing over-grinding of ilmenite. Background Technology

[0002] The Panxi region is my country's largest production base for vanadium-titanium magnetite and titanium concentrate. The beneficiation process follows the principle of "iron first, then titanium," employing a "step-by-step grinding and separation" method with weak magnetic separation for iron concentrate recovery. To reduce over-grinding of ilmenite, the first-stage iron beneficiation grinding is coarsened, and the second-stage grinding acts as a coarse-graining tailings disposal stage. The coarse iron concentrate undergoes second and third-stage grinding and separation to obtain qualified iron concentrate.

[0003] Therefore, iron ore beneficiation tailings are processed in three stages: primary, secondary, and tertiary. Currently, these three types of tailings are typically mixed and then subjected to a process of "grading - coarse-grained slag separation → primary coarse-grained iron removal → primary coarse-grained strong magnetic separation → grading and grinding → secondary coarse-grained iron removal → secondary coarse-grained strong magnetic separation → flotation," to recover ilmenite and obtain two products: coarse and fine titanium concentrate. Figure 2 As shown; however, in coarse-grained grinding and classification, the classification is carried out using a combination of "cyclone + high-frequency fine screen". Grinding is carried out by particle size classification, that is, the coarse particles are ground by the cyclone sediment and the material on the screen, while the fine particles under the screen enter the subsequent titanium beneficiation process. This inevitably leads to the grinding of ilmenite-rich intergrowths and monomers in the coarse particles, resulting in over-grinding and mudding of ilmenite, which affects the efficiency of the subsequent two-stage strong magnetic and flotation beneficiation, while also increasing the grinding volume and grinding cost.

[0004] Therefore, existing technologies need to be improved. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a mineral processing technology that reduces the over-grinding of ilmenite, improves the recovery rate of ilmenite, reduces grinding costs, and increases the economic benefits of enterprises.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] According to an aspect of the present invention, a beneficiation method for reducing over-grinding of ilmenite is provided, comprising the following steps:

[0008] 1) The coarse-grained portion of the iron ore tailings after classification is subjected to multi-stage spiral gravity separation to classify ilmenite according to the type of intergrowth, and obtain spiral concentrate, spiral middlings and spiral tailings, and use spiral middlings as the first grinding material;

[0009] 2) The spiral concentrate is subjected to a roughing operation to classify the ilmenite according to the type of intergrowth, and the oversize and undersize are obtained. The oversize is used as the second grinding material.

[0010] 3) The screened material is subjected to wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation to classify the ilmenite into a third type according to the intergrowth species, to obtain titanium concentrate and corresponding tailings, and the corresponding tailings are used as the third grinding material.

[0011] 4) The first, second and third grinding materials are mixed and ground. After grinding, when the TiO2 grade of the grinding product is less than 10%, it enters the fine-grained section for iron removal. When the TiO2 grade of the grinding product is greater than 10%, it enters the fine-grained section for iron removal.

[0012] In one embodiment of the present invention, in step 1), the fine-grained portion of the iron tailings after classification is subjected to fine-grained slag separation, fine-stage iron removal, fine-stage strong magnetic separation, fine-stage iron removal, fine-stage strong magnetic separation, and flotation operations in sequence.

[0013] In one embodiment of the present invention, in step 2), the spiral concentrate is subjected to weak magnetic iron removal and then coarsening; in step 3), the undersize is subjected to desulfurization and then wet strong magnetic, dry strong magnetic or electrostatic separation.

[0014] In one embodiment of the present invention, the intergrowth types of ilmenite are classified as: lean intergrowth, equigranular intergrowth, rich intergrowth, and single-grained intergrowth.

[0015] In one embodiment of the present invention, the volume of ilmenite in the poor intergrowth is 0-25%; the volume of ilmenite in the equigranular intergrowth is 25%-75%; and the volume of ilmenite in the rich intergrowth is 75%-99%.

[0016] In one embodiment of the present invention, in step 1), the ilmenite in the spiral concentrate is mostly monolithic and rich intergrowth; the ilmenite in the spiral middlings is mostly equigranular intergrowth and poor intergrowth; and the spiral tailings is mostly gangue and a small amount of poor intergrowth.

[0017] In one embodiment of the present invention, in step 1), the spiral tailings are directly fed into the tailings pond.

[0018] In one embodiment of the present invention, in step 2), the ilmenite in the oversize material is mostly equigranular intergrowth; the ilmenite in the undersize material is mostly single-celled and rich intergrowth.

[0019] In one embodiment of the present invention, in step 3), most of the ilmenite in the corresponding tailings is equigranular intergrowth, and a small portion is rich intergrowth.

[0020] In one embodiment of the present invention, in step 2), the spiral concentrate is coarsened using a screen with a 0.25-1mm aperture.

[0021] By adopting the above technical solution, the present invention has the following advantages compared with the prior art:

[0022] This invention fully utilizes the beneficiation process to classify ilmenite according to the type of intergrowth, and selectively grinds the separated ilmenite intergrowths, reducing the grinding of individual ilmenite and rich intergrowths, thereby reducing over-grinding of ilmenite, reducing grinding volume, increasing ilmenite recovery rate, and reducing grinding costs, resulting in significant economic benefits. Attached Figure Description

[0023] Figure 1 A schematic flow diagram of a mineral processing method for reducing over-grinding of ilmenite provided by the present invention is shown.

[0024] Figure 2 A flowchart of a prior art beneficiation method for ilmenite is shown;

[0025] Figure 3 The diagram shows a flow chart of an embodiment of a mineral processing method for reducing over-grinding of ilmenite provided by the present invention.

[0026] Figure 4 The diagram shows a flow chart of another embodiment of a mineral processing method for reducing over-grinding of ilmenite provided by the present invention. Detailed Implementation

[0027] It should be understood that the embodiments of the invention shown in the exemplary embodiments are merely illustrative. Although only a few embodiments have been described in detail in this invention, those skilled in the art will readily recognize that various modifications are possible without substantially departing from the teachings of the invention. Accordingly, all such modifications should be included within the scope of the invention. Other substitutions, modifications, variations, and deletions can be made to the design, operating conditions, and parameters of the following exemplary embodiments without departing from the spirit of the invention.

[0028] like Figure 1 As shown, the present invention provides a beneficiation method for reducing over-grinding of ilmenite, comprising the following steps:

[0029] Step S101: The coarse-grained portion of the iron ore tailings after classification is subjected to multi-stage spiral gravity separation to classify the ilmenite according to the type of intergrowth, and obtain spiral concentrate, spiral middlings and spiral tailings, and use the spiral middlings as the first grinding material;

[0030] Step S102: The spiral concentrate is subjected to a roughing operation to classify the ilmenite according to the type of intergrowth, obtaining the oversize and undersize, and the oversize is used as the second grinding material;

[0031] Step S103: Perform wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation on the screened material to classify the ilmenite into a third type according to the intergrowth, to obtain titanium concentrate and corresponding tailings, and use the corresponding tailings as the third grinding material.

[0032] Step S104: The first grinding material, the second grinding material and the third grinding material are mixed and ground. After grinding, when the TiO2 grade of the grinding product is less than 10%, it enters the fine-grained section for the first-stage iron removal operation. When the TiO2 grade of the grinding product is greater than 10%, it enters the fine-grained section for the second-stage iron removal operation.

[0033] Through the above-mentioned technical solution of the present invention, the present invention makes full use of the beneficiation operation to classify ilmenite according to the type of intergrowth, and selectively grinds the separated ilmenite intergrowths, thereby reducing the grinding of individual ilmenite and rich intergrowths, thus reducing the over-grinding of ilmenite, reducing the grinding volume, improving the recovery rate of ilmenite, reducing grinding costs, and achieving significant economic benefits.

[0034] In the above method, in step S101, the fine-grained portion of the iron tailings after classification is subjected to fine-grained slag separation, fine-stage iron removal, fine-stage strong magnetic separation, fine-stage iron removal, fine-stage strong magnetic separation, and flotation operations in sequence.

[0035] In the above method, in step S102, the spiral concentrate is subjected to weak magnetic iron removal and then coarsening; in step S103, the undersize is subjected to desulfurization and then wet strong magnetic, dry strong magnetic or electrostatic separation.

[0036] In the above method, the intergrowth types of ilmenite are classified as: lean intergrowth, equigranular intergrowth, rich intergrowth, and single-grained intergrowth.

[0037] In the above methods, the volume of ilmenite in poor intergrowths is 0-25%; the volume of ilmenite in equigranular intergrowths is 25%-75%; and the volume of ilmenite in rich intergrowths is 75%-99%.

[0038] In the above method, in step S101, the ilmenite in the spiral concentrate is mostly single-celled and rich intergrowth; the ilmenite in the spiral middlings is mostly equigranular intergrowth and poor intergrowth; and the spiral tailings is mostly gangue and a small amount of poor intergrowth.

[0039] In the above method, in step S101, the spiral tailings directly enter the tailings pond.

[0040] In the above method, in step S102, most of the ilmenite in the oversize material is equigranular intergrowth; most of the ilmenite in the undersize material is single-celled and rich intergrowth.

[0041] In the above method, in step S103, most of the ilmenite in the corresponding tailings is equigranular intergrowth, and a small portion is rich intergrowth.

[0042] In the above method, in step S102, the spiral concentrate is coarsened using a sieve with a 0.25-1mm aperture.

[0043] The technical solutions of the present invention will be described in detail below through specific embodiments.

[0044] like Figure 2 As shown, Figure 2 The typical production process flow chart for ilmenite recovery in the Panxi region is as follows: After iron ore tailings are classified, the coarse-grained portion is processed using a "strong magnetic + classifying grinding + strong magnetic + flotation" process to obtain coarse titanium concentrate. During the classifying grinding, a combination of "cyclone + high-frequency fine screen" is used for classification, and the coarse particles on the cyclone underflow and high-frequency screen are ground. However, these coarse particles also contain ilmenite monomers and rich intergrowths, which will cause this part of the ilmenite to be over-ground and muddy, thereby reducing the efficiency of subsequent strong magnetic and flotation separation, resulting in a higher titanium grade in the strong magnetic and flotation tailings, causing ilmenite loss, and also increasing the grinding volume and grinding cost.

[0045] Therefore, to reduce the over-grinding of ilmenite, this invention provides a method for reducing ilmenite over-grinding. The overall concept of this invention is to shift from grinding based on particle size to grinding based on the type of ilmenite intergrowth. Ilmenite intergrowths are categorized as follows: lean intergrowths (ilmenite volume percentage 0-25%), equigranular intergrowths (ilmenite volume percentage 25%-75%), rich intergrowths (ilmenite volume percentage 75%-99%), and individual ilmenite. The ilmenite intergrowths are classified using mineral processing, and then the separated ilmenite intergrowths are ground to liberate the individual ilmenite.

[0046] like Figure 3 As shown, Figure 3 This diagram illustrates a flow chart of an embodiment of a beneficiation method for reducing over-grinding of ilmenite provided by the present invention. After classification, the coarse-grained portion of the iron ore beneficiation tailings is processed using a multi-stage spiral mill (e.g., Figure 3The spiral roughing, spiral scavenging, spiral cleaning I, spiral cleaning II, and spiral cleaning III processes described herein achieve the first classification according to the type of ilmenite intergrowth, obtaining spiral concentrate (ilmenite mostly in single-celled and rich intergrowths), spiral middlings (ilmenite mostly in equigranular and lean intergrowths), and spiral tailings (mostly gangue, containing a small amount of lean ilmenite intergrowths). Since the spiral tailings mainly consist of gangue minerals and a small amount of lean ilmenite intergrowths, they can be directly fed into the tailings pond. Since the spiral middlings mainly consist of lean and equigranular intergrowths of ilmenite, they can be used as grinding feedstock ①. After weak magnetic iron removal, the spiral concentrate is screened with a 0.25mm-1mm mesh screen. (Preferably a 0.5mm mesh screen) is used for coarse classification to achieve a second classification according to the type of ilmenite intergrowth, obtaining oversize (most ilmenite is equigranular intergrowth) and undersize (most ilmenite is monolithic and rich intergrowth). The oversize can be used as grinding feed ②. After desulfurization, the undersize is subjected to wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation to achieve a third classification according to the type of ilmenite intergrowth, obtaining titanium concentrate and corresponding tailings (most ilmenite is equigranular intergrowth, a small part is rich intergrowth). The corresponding tailings can be used as grinding feed ③. After the three grinding feeds ①, ②, and ③ are mixed and ground, the TiO2 grade of the grinding product is less than 10%, and the fine-grained part adopts a fine-stage iron removal operation.

[0047] like Figure 4 As shown, Figure 4 This diagram illustrates a flow chart of another embodiment of a beneficiation method for reducing over-grinding of ilmenite provided by the present invention. After classification, the coarse-grained portion of the iron ore beneficiation tailings is processed using a multi-stage spiral (e.g., Figure 4The spiral roughing, spiral scavenging, spiral cleaning I, spiral cleaning II, and spiral cleaning III processes described herein achieve the first classification according to the type of ilmenite intergrowth, obtaining spiral concentrate (ilmenite mostly in single-celled and rich intergrowths), spiral middlings (ilmenite mostly in equigranular and lean intergrowths), and spiral tailings (mostly gangue, containing a small amount of lean ilmenite intergrowths). Since the spiral tailings mainly consist of gangue minerals and a small amount of lean ilmenite intergrowths, they can be directly fed into the tailings pond. Since the spiral middlings mainly consist of lean and equigranular intergrowths of ilmenite, they can be used as grinding feedstock ①. After weak magnetic iron removal, the spiral concentrate is screened with a 0.25mm-1mm mesh screen. (Preferably a 0.5mm mesh screen) is used for coarse classification to achieve a second classification according to the type of ilmenite intergrowth, obtaining oversize (most ilmenite is equigranular intergrowth) and undersize (most ilmenite is monolithic and rich intergrowth). The oversize can be used as grinding feed ②. After desulfurization, the undersize is subjected to wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation to achieve a third classification according to the type of ilmenite intergrowth, obtaining titanium concentrate and corresponding tailings (most ilmenite is equigranular intergrowth, a small part is rich intergrowth). The corresponding tailings can be used as grinding feed ③. After the three grinding feeds ①, ②, and ③ are mixed and ground, the TiO2 grade of the grinding product is greater than 10%, and it enters the fine-grained part for fine two-stage iron removal.

[0048] Therefore, the innovation of this invention mainly lies in utilizing the differences in specific gravity, specific magnetic susceptibility, and electrical properties of different ilmenite intergrowths. By employing spiral gravity separation, wet strong magnetic separation, dry strong magnetic separation, and electrostatic separation, ilmenite is classified according to the type of intergrowth, thereby achieving targeted grinding, reducing the over-grinding and mudding phenomenon of ilmenite, which improves the subsequent ilmenite separation efficiency, while reducing the grinding volume and lowering the grinding cost.

[0049] Therefore, the present invention reduces the over-grinding of ilmenite in the mineral processing process. Figure 3 and 4 ) and the original process ( Figure 2 Compared to the previous process, the coarse-grained part has changed from the "strong magnetic + classifying grinding + strong magnetic + flotation" process to the "multi-stage spiral gravity separation + wet strong magnetic or dry strong magnetic or electrostatic separation" process. The grinding amount will be reduced by more than 50%, achieving selective grinding of ilmenite intergrowths, resulting in significant economic benefits.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications or equivalent substitutions made to the present invention without departing from the spirit and scope thereof should be covered within the protection scope of the claims of the present invention.

Claims

1. A beneficiation method for reducing over-grinding of ilmenite, characterized in that, Includes the following steps: 1) The coarse-grained portion of the iron ore tailings after classification is subjected to multi-stage spiral gravity separation to classify ilmenite according to the type of intergrowth, obtaining spiral concentrate, spiral middlings, and spiral tailings. The spiral middlings is used as the first grinding feed. The ilmenite in the spiral concentrate is mostly single-celled and rich intergrowths; the ilmenite in the spiral middlings is mostly equigranular intergrowths and lean intergrowths; and the ilmenite in the spiral tailings is mostly gangue and a small amount of lean intergrowths. 2) The spiral concentrate is subjected to a roughing operation to classify the ilmenite into intergrowths for a second time, obtaining oversize and undersize. The oversize is used as the second grinding material, wherein the ilmenite in the oversize is mostly equigranular intergrowths; the ilmenite in the undersize is mostly single-celled and rich intergrowths. 3) The screened material is subjected to wet strong magnetic separation, dry strong magnetic separation, or electrostatic separation to classify the ilmenite into intergrowths for the third time, to obtain titanium concentrate and corresponding tailings, and the corresponding tailings are used as the third grinding material. The ilmenite in the corresponding tailings is mostly equigranular intergrowths and a small part is rich intergrowths. 4) The first, second and third grinding materials are mixed and ground. After grinding, when the TiO2 grade of the grinding product is less than 10%, it enters the fine-grained section for iron removal. When the TiO2 grade of the grinding product is greater than 10%, it enters the fine-grained section for iron removal.

2. The beneficiation method for reducing over-grinding of ilmenite according to claim 1, characterized in that, In step 1), the fine-grained portion of the iron tailings after classification is subjected to fine-grained slag separation, fine-stage iron removal, fine-stage strong magnetic separation, fine-stage iron removal, fine-stage strong magnetic separation, and flotation operations in sequence.

3. The beneficiation method for reducing over-grinding of ilmenite according to claim 1, characterized in that, In step 2), the spiral concentrate is subjected to weak magnetic iron removal and then coarsening; in step 3), the undersize is subjected to desulfurization and then wet strong magnetic, dry strong magnetic or electrostatic separation.

4. The beneficiation method for reducing over-grinding of ilmenite according to claim 1, characterized in that, The volume of ilmenite in the lean intergrowth is 0-25%; the volume of ilmenite in the equigranular intergrowth is 25%-75%; and the volume of ilmenite in the rich intergrowth is 75%-99%.

5. The beneficiation method for reducing over-grinding of ilmenite according to claim 1, characterized in that, In step 1), the spiral tailings are directly fed into the tailings pond.

6. The beneficiation method for reducing over-grinding of ilmenite according to claim 1, characterized in that, In step 2), the spiral concentrate is coarsened using a sieve with a 0.25-1mm aperture.

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