Method for grinding and separating sefstromite

Abstract

The invention discloses a sefstromite grinding and selecting method which comprises the following steps: performing coarse grinding and selecting on a sefstromite raw material to separate out fine-grained ilmenite and coarse grinding and selecting weak magnetic concentrate; carrying out spiral-flow type grading on the coarse grinding and separation weak magnetic concentrate, carrying out fine grinding on a sand setting product obtained by spiral-flow type grading, and carrying out spiral-flow type grading on an obtained ore discharging product again; an overflow product obtained through spiral-flow type grading is graded through a high-frequency screen, and an oversize product of the high-frequency screen is subjected to superfine grinding; mixing the ore grinding product obtained by superfine grinding with the undersize product of the high-frequency sieve, and performing primary separation to obtain primary separation section weak magnetic concentrate and primary separation section weak magnetic tailings; and elutriating the weak magnetic concentrate in the primary separation section to obtain the vanadium-titanium-iron concentrate. According to the vanadium-titanium-iron ore grinding separation method, the cost of the vanadium-titanium-iron ore concentrate purification process can be reduced, the product quality of the vanadium-titanium-iron ore concentrate is improved, and efficient recovery of the vanadium-titanium-iron ore concentrate is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of vanadium-titanium iron concentrate purification equipment, and particularly relates to a grinding and separation method for vanadium-titanium iron ore. Background Art

[0002] At present, iron concentrates are divided into two types. The first type is vanadium-titanium iron concentrate, which is purified from vanadium-titanium magnetite; the second type is ordinary iron concentrate, which is purified from magnetite. Vanadium-titanium magnetite is distributed in magmatic rocks, while most magnetite is distributed in metamorphic rocks. Different geological structures result in the composition of vanadium-titanium magnetite being more complex than that of magnetite. Correspondingly, the separation process of vanadium-titanium iron concentrate is more complex than that of ordinary iron concentrate. If the same purity of iron concentrate is to be obtained, the difficulty of vanadium-titanium iron concentrate is greater than that of ordinary iron concentrate. With the development of the economy and the advancement of urbanization, the demand for high-quality vanadium-titanium iron concentrate is increasing, and it is also becoming more and more important for the development of the national economy and the steel industry. Obtaining high-quality vanadium-titanium iron concentrate can only rely on increasing the fineness of vanadium-titanium iron concentrate.

[0003] Since vanadium-titanium iron concentrate is recovered from vanadium-titanium magnetite and titanium resources need to be comprehensively recovered subsequently, the grinding and separation process needs to comprehensively consider the recovery particle size of ilmenite. At least three stages of grinding and separation operations are required. The first two stages are mainly used to separate ilmenite, and the improvement of the quality of vanadium-titanium iron concentrate is mainly reflected in the third stage, and even the fourth stage of grinding and separation. The third stage and the fourth stage of grinding and separation are mainly used to increase the fineness of vanadium-titanium iron concentrate, that is, to make its particle size finer, in order to achieve the purpose of improving the quality of vanadium-titanium iron concentrate. However, the increased grinding and separation operations and the overly fine vanadium-titanium iron concentrate have significantly increased the production energy consumption of vanadium-titanium iron concentrate and the cost of concentrate filtration, resulting in the following problems in the existing vanadium-titanium iron concentrate purification process: high production cost, low efficiency, and poor product quality. Summary of the Invention

[0004] To solve the above problems, the present invention provides a grinding and separation method for vanadium-titanium iron ore, which can reduce the cost of the vanadium-titanium iron concentrate purification process, improve the product quality of vanadium-titanium iron concentrate, and achieve the efficient recovery of vanadium-titanium iron concentrate.

[0005] A grinding and separation method for vanadium-titanium iron ore provided by the present invention includes:

[0006] Coarsely grinding and separating the vanadium-titanium iron ore raw material to separate fine-grained ilmenite and coarsely ground weak magnetic concentrate;

[0007] Performing hydrocyclone classification on the coarsely ground weak magnetic concentrate, finely grinding the sand product obtained by hydrocyclone classification, and performing hydrocyclone classification on the discharged ore product again;

[0008] Classifying the overflow product obtained by hydrocyclone classification using a high-frequency screen, and ultrafinely grinding the product on the high-frequency screen;

[0009] Mix the grinding products obtained by ultrafine grinding and the products passing through the high-frequency screen, and then conduct preliminary separation to obtain the weakly magnetic concentrate in the preliminary separation stage and the weakly magnetic tailings in the preliminary separation stage.

[0010] Wash the weakly magnetic concentrate in the preliminary separation stage to obtain vanadium-titanium iron concentrate.

[0011] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, the ultrafine grinding of the products on the high-frequency screen is as follows:

[0012] Perform IsaMill on the products on the high-frequency screen.

[0013] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, the preliminary separation after mixing the grinding products obtained by ultrafine grinding and the products passing through the high-frequency screen is as follows:

[0014] Mix the grinding products obtained by ultrafine grinding and the products passing through the high-frequency screen, and then conduct drum weak magnetic separation.

[0015] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, the fine grinding of the sand products obtained by hydrocyclone classification is as follows:

[0016] Perform tower mill on the sand products obtained by hydrocyclone classification.

[0017] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, after washing the weakly magnetic concentrate in the preliminary separation stage, washing tailings are also obtained.

[0018] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, after obtaining the washing tailings, it further includes:

[0019] Mix the washing tailings and the weakly magnetic tailings in the preliminary separation stage to obtain iron separation tailings.

[0020] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, the hydrocyclone classification of the weakly magnetic concentrate in the rough grinding and separation includes:

[0021] Feed the weakly magnetic concentrate in the rough grinding and separation into a cyclone for hydrocyclone classification.

[0022] Preferably, in the above-mentioned grinding and separation method for vanadium-titanium iron ore, the rough grinding and separation of the vanadium-titanium iron ore raw material includes:

[0023] Conduct two-stage grinding and separation on the vanadium-titanium iron ore raw material.

[0024] As can be seen from the above description, in the method for grinding and separating vanadium-titanium iron ore provided by the present invention, since the vanadium-titanium iron ore raw material is first coarsely ground and separated to obtain fine-grained ilmenite and weakly magnetic concentrate from coarse grinding and separation, then the weakly magnetic concentrate from coarse grinding and separation is subjected to hydrocyclone classification, the sand product obtained from hydrocyclone classification is finely ground, and the discharge product obtained is subjected to hydrocyclone classification again; the overflow product obtained from hydrocyclone classification is classified by a high-frequency screen, and the product on the high-frequency screen is ultrafinely ground. It can be seen that here, unlike the prior art, the sand product and the product on the high-frequency screen are not mixed for grinding, but are ground separately, thus avoiding the problems of increased grinding time and increased energy consumption caused by the product on the high-frequency screen, and also avoiding unnecessary over-grinding of the sand product. Moreover, the ultrafine grinding process for the product on the high-frequency screen can reduce time and the number of equipment compared with the prior art. Since this method further includes mixing the grinding product obtained from ultrafine grinding and the product under the high-frequency screen and then performing primary separation to obtain weakly magnetic concentrate in the primary separation stage and weakly magnetic tailings in the primary separation stage; washing the weakly magnetic concentrate in the primary separation stage to obtain vanadium-titanium iron concentrate. It can be seen that the washing process adopted here can avoid the inclusion of gangue minerals and high-quality vanadium-titanium iron concentrate compared with the simple drum magnetic separation method adopted in the prior art. It realizes the separation of vanadium-titanium iron concentrate and tailings by the multiple actions of magnetic force, gravity and upward water flow lift force, effectively separating the fine-grained gangue minerals and further improving the quality of vanadium-titanium iron concentrate. Therefore, it can be seen that the above method can reduce the cost in the purification process of vanadium-titanium iron concentrate, improve the product quality of vanadium-titanium iron concentrate, and achieve the efficient recovery of vanadium-titanium iron concentrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0026] Figure 1 Schematic diagram of an embodiment of a method for grinding and separating vanadium-titanium iron ore provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The core of the present invention is to provide a method for grinding and separating vanadium-titanium iron ore, which can reduce the cost in the purification process of vanadium-titanium iron concentrate, improve the product quality of vanadium-titanium iron concentrate, and achieve the efficient recovery of vanadium-titanium iron concentrate.

[0028] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] An embodiment of the ilmenite grinding and separation method provided by the present invention is as Figure 1 shown. Figure 1 It is a schematic diagram of an embodiment of the ilmenite grinding and separation method provided by the present invention. The method may include the following steps:

[0030] S1: Coarsely grind and separate the ilmenite raw material to separate fine-grained ilmenite and coarsely ground weak magnetic concentrate.

[0031] Specifically, this coarse grinding and separation process may include two-stage grinding and separation of the ilmenite raw material. First, feed the incoming grinding raw material (ilmenite raw material) into the first-stage ball mill. The product of the first-stage ball mill is fed into the first-stage hydrocyclone for classification. The sand product obtained from the hydrocyclone classification is returned to the first-stage ball mill, and the overflow product of the classification is fed into the first-stage drum weak magnetic separator. The magnetic field intensity can be 3000 Oe to 4500 Oe to obtain the first-stage weak magnetic concentrate and the first-stage iron separation tailings. This system is the first-stage grinding and separation system, and the purpose is to separate qualified coarse-grained ilmenite and titanomagnetite. The particle size of the hydrocyclone classification is mainly the qualified particle size of the coarse-grained ilmenite, and the grinding fineness can be that the content of -0.074 mm is 35% to 45%. Then, the first-stage weak magnetic concentrate is fed into the second-stage hydrocyclone for classification. The sand product obtained from the classification is fed into the second-stage ball mill, and the overflow product of the classification is fed into the second-stage drum weak magnetic separator. The magnetic field intensity can be 3000 Oe to 4000 Oe to obtain the coarsely ground weak magnetic concentrate and the second-stage iron separation tailings. This system is the second-stage grinding and separation system, and the purpose is to separate qualified fine-grained ilmenite (second-stage iron separation tailings) and titanomagnetite (coarsely ground weak magnetic concentrate). The particle size of the hydrocyclone classification is mainly the qualified particle size of the fine-grained ilmenite (second-stage iron separation tailings), and the grinding fineness can be that the content of -0.074 mm is 60% to 75%.

[0032] S2: Perform hydrocyclone classification on the coarsely ground weak magnetic concentrate, finely grind the sand product obtained from the hydrocyclone classification, and perform hydrocyclone classification on the obtained discharge product again.

[0033] Specifically, the rough grinding and weak magnetic concentrate obtained in the above step S1 can be fed into a hydrocyclone for hydrocyclone classification. Then, the sand product obtained from this hydrocyclone classification can be specifically ground finely by means of tower grinding. Specifically, tower grinding is achieved through a slowly rotating agitation screw. By utilizing the effects of centrifugal force, gravity, and friction, the comminution medium and the material are made to achieve an orderly movement cycle and a macroscopic force balance, thereby subjecting the material to comprehensive actions such as strong extrusion, grinding, and micro-shearing. Its working principle is that under the action of the slowly rotating agitation screw, the comminution medium and the material achieve an orderly movement cycle under the effects of centrifugal force, gravity, and friction. The material rises spirally within the agitation screw and descends spirally between the inner lining and the outer edge of the screw. Microscopically, due to uneven force, a dynamic movement speed difference and force change are formed, thereby realizing comprehensive actions such as extrusion, grinding, breaking, micro-shearing, and splitting of the material. The qualified fine material rises with the conveying medium and overflows by gravity from the upper part of the tower mill cylinder after internal classification.

[0034] S3: Classify the overflow product obtained from the hydrocyclone classification using a high-frequency screen, and perform ultrafine grinding on the product retained on the high-frequency screen;

[0035] It should be noted that the screen aperture size of this high-frequency screen can be preferably 0.074 mm. Here, the ultrafine grinding can preferably be performed by subjecting the product retained on the high-frequency screen to IsaMill grinding. This IsaMill grinding method can solve the problem of difficult grinding of the product retained on the high-frequency screen and the need for ultrafine grinding. Its working principle is that a high-speed rotating agitation disk drives the grinding medium (such as ceramic balls) to perform axial movement and self-rotation. Multiple independent grinding chambers are formed between the agitation disks. The grinding medium circulates in each chamber, and the mineral particles are finely ground under the action of the high-speed moving grinding medium. This design enables the minerals and the grinding medium to be distributed according to particle size from small to large, achieving "grinding large ones with large ones and small ones with small ones" selective grinding. Its advantages include: narrow particle size distribution of the grinding product, avoiding over-grinding and under-grinding, increasing the recovery rate, low energy consumption, strong adaptability, being able to adjust the grinding fineness according to the fluctuation of the feed volume into the mill. Under the same processing capacity, the cylinder volume is only one-fifth of that of a ball mill.

[0036] S4: Mix the grinding product obtained from the ultrafine grinding and the product passing through the high-frequency screen and perform primary separation to obtain the weak magnetic concentrate in the primary separation stage and the weak magnetic tailings in the primary separation stage;

[0037] Specifically, the preliminary selection process can be to mix the grinding products obtained by ultrafine grinding and the products screened by the high-frequency screen and then feed them into a drum weak magnetic separator for drum weak magnetic separation. The magnetic field intensity can be selected from 3000 Oe to 4000 Oe. Among them, the drum weak magnetic separator is a device for separating magnetic minerals using a weak magnetic field, which consists of a magnetic system (usually composed of permanent magnets or electromagnets), a cylinder, a trough, a frame, and a driving device. According to the different structures of the trough, the drum magnetic separator can be divided into a forward flow type, a reverse flow type, and a semi-reverse flow type. For the forward flow type magnetic separator, the pulp enters from the bottom of the trough, and the magnetic mineral particles are adsorbed on the surface of the rotating cylinder. After rotating to the weak magnetic field area with the cylinder, they are discharged into the concentrate trough by the ore discharge water pipe, while the non-magnetic mineral particles are discharged from the gap below the cylinder. For the reverse flow type magnetic separator, the pulp enters from the upper part of the trough, opposite to the rotation direction of the cylinder. The magnetic mineral particles are adsorbed and discharged at the top with the rotation of the cylinder, and the tailings are discharged from the bottom of the trough. For the semi-reverse flow type magnetic separator, the pulp enters the separation space in a loose suspension state, the magnetic mineral particles are adsorbed onto the surface of the cylinder, the tailings are discharged from the bottom of the trough, and the concentrate overflows and discharges from the upper part. Its advantages include: high efficiency and energy saving, simple structure, large processing capacity, strong adaptability, and convenient maintenance.

[0038] S5: Wash the weak magnetic concentrate in the preliminary selection stage to obtain vanadium-titanium iron concentrate.

[0039] Specifically, the weak magnetic concentrate in the preliminary selection stage can be fed into a washing machine for washing. The magnetic field intensity can be selected from 2000 Oe to 3000 Oe. In this way, high-quality vanadium-titanium iron concentrate can be obtained. The washing machine (such as a fully automatic washing magnetic separator) separates materials through a magnetic field. Its principle is to use the attracting effect of the magnetic field on magnetic minerals to make magnetic minerals such as iron powder settle, while the tailings (non-magnetic minerals) rise with the water flow and are discharged. By precisely controlling the magnetic field intensity and direction, the washing machine can efficiently separate magnetic minerals and non-magnetic minerals, and can include the following steps: (1) Feeding: Feed the weak magnetic concentrate in the preliminary selection stage into the washing machine, and the pulp concentration is usually controlled at 35% - 40%; (2) Separation: Under the action of the magnetic field, magnetic minerals are adsorbed and settle, and non-magnetic minerals are discharged with the water flow; (3) Separation of concentrate and tailings: The iron grade of the washed concentrate is significantly improved, and the tailings can be further recycled or processed. The advantages of this washing machine include: (1) Improving the concentrate grade: effectively removing non-magnetic impurities in the tailings and significantly improving the grade of iron concentrate; (2) Reducing the impurity content: significantly reducing the content of impurities such as SiO2 in the iron concentrate; (3) High degree of automation: adopting a fully automatic program control, being able to adapt to fluctuations in ore quantity and preventing the phenomenon of overflow and running black. Generally speaking, feeding the weak magnetic concentrate in the preliminary selection stage into the washing machine for washing is an efficient and economical mineral purification process, which can significantly improve the quality of the concentrate and reduce the impurity content.

[0040] It should also be noted that as mines are now increasingly moving into deep mining, the disseminated particle size of vanadium-titanium iron concentrate is getting finer and finer. To obtain high-quality vanadium-titanium iron concentrate, fine grinding or even ultrafine grinding is required. However, the existing magnetic separators cannot solve the problem of the intermingling of ultrafine vanadium-titanium iron concentrate and ultrafine gangue, while the elutriator can solve this problem. Moreover, after elutriating the weakly magnetic concentrate in the primary separation stage, elutriation tailings can be obtained. Further, after obtaining the elutriation tailings, it can also include mixing the elutriation tailings and the weakly magnetic tailings in the primary separation stage to form iron separation tailings. This is the three-stage grinding and separation system, which can obtain high-quality iron concentrate. In addition, the particle sizes classified by the hydrocyclone and the high-frequency screen are mainly the qualified particle sizes of high-quality titanomagnetite, and the product fineness is determined by the dissociation of high-quality vanadium-titanium iron concentrate. Among them, the fineness of the sand settling tower grinding with a particle size of -0.045mm is 80% to 90%, and the fineness of the abrasive sand ground by the high-frequency screen oversize product with a particle size of -0.038mm is 85% to 100%. It can be seen that the three-stage grinding uses the method of classified sand settling and oversize grinding by the high-frequency screen, which can improve the grinding efficiency. The three-stage magnetic separation adopts a combination of rough separation and fine separation. The rough separation uses a cylindrical weak magnetic separator, which can separate coarse-grained gangue minerals earlier and create favorable particle size conditions for subsequent fine separation and elutriation. The fine separation uses an elutriator, which can reduce the intermingling of fine mud in the magnetic separation process and is more conducive to improving the quality of vanadium-titanium iron concentrate.

[0041] As can be seen from the above description, in the embodiment of the method for grinding and separating vanadium-titanium iron ore provided by the present invention, since the vanadium-titanium iron ore raw material is first roughly ground and separated to obtain fine-grained ilmenite and weakly magnetic concentrate from rough grinding and separation, then the weakly magnetic concentrate from rough grinding and separation is subjected to hydrocyclone classification, the sand products obtained from hydrocyclone classification are finely ground, and the discharged products obtained are subjected to hydrocyclone classification again; the overflow products obtained from hydrocyclone classification are classified by a high-frequency screen, and the oversize products of the high-frequency screen are ultrafinely ground. It can be seen that here, unlike the prior art, the sand products and the oversize products of the high-frequency screen are not mixed for grinding, but are ground separately, thus avoiding the problems of increased grinding time and increased energy consumption caused by the oversize products of the high-frequency screen, and also avoiding unnecessary over-grinding of the sand products. Moreover, the ultrafine grinding process for the oversize products of the high-frequency screen can reduce time and equipment quantity compared with the prior art. Since the method also includes mixing the grinding products obtained from ultrafine grinding and the undersize products of the high-frequency screen and then performing primary separation to obtain weakly magnetic concentrate and weakly magnetic tailings in the primary separation stage; elutriating the weakly magnetic concentrate in the primary separation stage to obtain vanadium-titanium iron concentrate, it can be seen that the elutriation process adopted here can avoid the intermingling of gangue minerals and high-quality vanadium-titanium iron concentrate compared with the method of simply performing cylindrical magnetic separation in the prior art. It uses the multiple actions of magnetic force, gravity, and upward water flow lift force to separate vanadium-titanium iron concentrate from tailings, effectively separating fine-grained gangue minerals and further improving the quality of vanadium-titanium iron concentrate. Thus, it can be seen that the above method can reduce the cost in the process of purifying vanadium-titanium iron concentrate, improve the product quality of vanadium-titanium iron concentrate, and achieve the efficient recovery of vanadium-titanium iron concentrate.

[0042] The advantages of the above method are as follows:

[0043] First of all, the above method adopts the method of grinding with different qualities. In the existing iron separation process, in the three-stage grinding, the sand deposited by the three-stage cyclone and the products on the high-frequency screen are mixed for grinding. However, there are great differences in the grindability of these two products. The cyclone mainly relies on gravity classification, and most of the classified sand deposits are products with relatively high TFe grades. This product is mainly composed of rich intergrowths and monomers of vanadium-titanium magnetite, with a dissociation degree as high as 88%. High-quality vanadium-titanium iron concentrate can be obtained through simple grinding. The products on the high-frequency screen are mainly composed of poor intergrowths of vanadium-titanium magnetite, with a dissociation degree of only 75%, and deep fine grinding is required to obtain high-quality vanadium-titanium iron concentrate. Specifically, a grindability comparison test was conducted on the sand deposited by the three-stage cyclone and the products on the high-frequency screen of a certain ore dressing plant in Panxi. Among them, the TFe grade of the cyclone sand deposit was 56.89%, and the content of -0.045mm was 38.46%; the TFe grade of the products on the high-frequency screen was 54.43%, and the content of -0.045mm was 76.48%. Laboratory grinding and separation tests were carried out on these two products respectively, and the test results are shown in Table 1.

[0044] Table 1 Test results of grinding and separation of two products

[0045]

[0046] It can be seen from Table 1 that to reach the same TFe grade, the grinding time of the products on the high-frequency screen increases by 160% compared with that of the cyclone sand deposit, and the grinding fineness increases by 57.17%. Obviously, if these two products are mixed for grinding, to obtain high-quality iron concentrate, the energy consumption of grinding will inevitably increase, which will cause unnecessary over-grinding of the cyclone sand deposit.

[0047] By adopting the above method provided by this application, the investment in the production line and the production cost for improving the quality of vanadium-titanium iron concentrate can be greatly reduced. Taking a certain ore dressing plant in Panxi as an example, the TFe grade of the second-stage weak magnetic concentrate is about 55.5%. To upgrade the iron concentrate to more than 58%, when using the conventional three-stage mixed grinding and separation process, the number of tower mills (rated installed power 1120kW) required for the three stages reaches 12. By adopting the above method provided by this application, only 9 tower mills (rated installed power 1120kW) are required for grinding with different qualities. The cost of 1 tower mill + classification system is about 15 million yuan. By adopting the method of this application, the equipment cost can be reduced by about 45 million yuan. At the same time, the annual operating cost of about 16 million yuan for 3 three-stage grinding + classification systems can also be reduced.

[0048] Secondly, the above method provided by this application adopts the way of superfine grinding of AI sand. Since the oversize products of the high-frequency screen mainly consist of vanadium-titanium magnetite lean intergrowths, the gangue minerals in vanadium-titanium magnetite are more than 0.6 harder than vanadium-titanium magnetite. If vanadium-titanium magnetite is to be dissociated from gangue minerals with relatively high hardness, grinding equipment with higher requirements for fine grinding degree is needed. This AI sand mill can meet this requirement. This equipment adopts a horizontal (the transmission shaft is in the horizontal direction) high-intensity stirring grinding method, and can efficiently achieve the effect of superfine grinding without an internal screen or supporting closed-circuit classification equipment. The oversize products of a certain concentrator in Panxi were subjected to comparative grinding using a tower mill and an AI sand mill. When the same grinding fineness reached 95% of the content of -0.045mm, the tower mill took 13 minutes, while the AI sand mill took 10 minutes. According to the measurement of the oversize product ore volume, under the same throughput and rated installed power, using the AI sand mill requires one less device than the tower mill. Here, whether using the tower mill or the AI sand mill, the cost will increase, but the cost increase using the AI sand mill is less. Among them, the investment and infrastructure cost of the AI sand mill is about 20 million yuan, and the investment and infrastructure cost of the tower mill + classification is about 25 million yuan. Moreover, in terms of operating cost, the operating cost of the AI sand mill is 50% less than that of the tower mill.

[0049] Finally, the above method provided by this application adopts the way of elutriation concentration. The conventional iron magnetic separation process uses a one-rougher and one-cleaner process composed of a single-stage cylindrical magnetic separator or a two-stage cylindrical magnetic separator. However, in the magnetic separation of superfine-ground vanadium-titanium magnetite, the improvement of the separation effect of the cylindrical magnetic separator on superfine-ground vanadium-titanium magnetite is limited. The gangue minerals after superfine grinding are easily mixed with high-quality vanadium-titanium iron concentrate, affecting the quality of the final vanadium-titanium iron concentrate. The elutriator uses the combined action of magnetic force, gravity and upward water flow lift force, and finally discharges the separated tailings from the overflow tank, and the concentrate is discharged through the bottom flow valve at the lower part. The elutriator is beneficial to the separation of superfine-ground vanadium-titanium magnetite. However, the relatively coarse-grained lean intergrowth vanadium-titanium magnetite is easily discharged with the concentrate through the valve at the lower part, affecting the quality of the final vanadium-titanium iron concentrate. Therefore, the solution provided by this application adopts a combined magnetic separation process of a cylindrical magnetic separator + an elutriator. Among them, the roughing uses a cylindrical magnetic separator, and the cleaning uses an elutriator. The roughing uses a cylindrical magnetic separator to pre-discharge the coarse-grained gangue minerals, narrowing the particle size range of the concentrate of the cylindrical magnetic separator and creating a range conducive to magnetic separation particle size for the elutriator; the cleaning uses an elutriator to effectively separate the fine-grained gangue minerals, further improving the quality of vanadium-titanium iron concentrate. The products of three-stage superfine grinding of a certain concentrator in Panxi were subjected to a comparative test using the conventional method and the method provided by this application. The test results are shown in Table 2.

[0050] Table 2 Comparison test results of two magnetic separations

[0051]

[0052] As can be seen from Table 2, when a one-rougher and one-cleaner drum magnetic separator is used for beneficiation, the grade of TFe in the final iron concentrate only increases by 0.31 percentage points. However, when a rougher drum magnetic separator and a cleaning washer are used for beneficiation, the grade of TFe in the final iron concentrate can increase by 1.13 percentage points.

[0053] In summary, by using the method provided in this application, high-quality vanadium-titanium iron concentrate can be obtained, and the equipment cost and operating cost can be reduced.

[0054] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for grinding and separating vanadium-titanium magnetite, characterized in that, Including: Coarsely grinding and separating ilmenite ore to separate fine-grained ilmenite and weakly magnetic concentrate from coarse grinding and separation; Performing hydrocyclone classification on the weakly magnetic concentrate from coarse grinding and separation, finely grinding the sand product obtained from hydrocyclone classification, and performing hydrocyclone classification on the discharge product obtained again; Classifying the overflow product obtained from hydrocyclone classification using a high-frequency screen, and ultrafinely grinding the product on the high-frequency screen; Mixing the grinding product obtained from ultrafine grinding and the product under the high-frequency screen and performing preliminary separation to obtain weakly magnetic concentrate and weakly magnetic tailings in the preliminary separation stage; Performing elutriation on the weakly magnetic concentrate in the preliminary separation stage to obtain vanadium-titanium iron concentrate.

2. The ilmenite grinding and separation method according to claim 1, wherein The ultrafine grinding of the product on the high-frequency screen is as follows: Performing IsaMill grinding on the product on the high-frequency screen.

3. The ilmenite grinding and separation method according to claim 1, wherein The preliminary separation after mixing the grinding product obtained from ultrafine grinding and the product under the high-frequency screen is as follows: Mixing the grinding product obtained from ultrafine grinding and the product under the high-frequency screen and performing drum weak magnetic separation.

4. The ilmenite grinding and separation method according to claim 1, wherein The fine grinding of the sand product obtained from hydrocyclone classification is as follows: Performing tower mill grinding on the sand product obtained from hydrocyclone classification.

5. The ilmenite grinding and separation method according to claim 1, wherein After performing elutriation on the weakly magnetic concentrate in the preliminary separation stage, elutriation tailings are also obtained.

6. The ilmenite grinding and separation method according to claim 5, characterized in that, After obtaining the elutriation tailings, it further includes: Mixing the elutriation tailings and the weakly magnetic tailings in the preliminary separation stage to obtain iron separation tailings.

7. The ilmenite grinding and separation method according to claim 1, characterized in that, The hydrocyclone classification of the weakly magnetic concentrate from coarse grinding and separation includes: Feeding the weakly magnetic concentrate from coarse grinding and separation into a hydrocyclone for hydrocyclone classification.

8. The ilmenite grinding and separation method according to claim 1, wherein The coarse grinding and separation of ilmenite ore includes: Performing two-stage grinding and separation on the ilmenite ore.

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