Three-section grinding separation device and method for vanadium-titanium magnetite concentrate

Abstract

The invention provides a vanadium-titanium magnetite concentrate three-section grinding separation device. The device comprises an ore separation box; the ore separation box is provided with a feeding end and a discharging end; the upgrading raw ore tank is connected with the feeding end; the cyclone is connected with the discharging end; the cyclone is provided with a tower mill; a feeding hole of the magnetic separator is connected with a discharging hole of the cyclone; the magnetic separator is provided with a tailing outlet and a magnetic separation outlet; the filtering machine is connected with the magnetic separation ore outlet; and the filter is provided with a concentrate outlet. Compared with the prior art, the three-section grinding and separation device for the vanadium-titanium magnetite concentrate adopts a specific structure and a connection relation, overall good interaction is achieved, through three-section grinding and separation, the quality of the vanadium-titanium magnetite concentrate is effectively improved, it is ensured that the quality of the vanadium-titanium magnetite concentrate is improved, the yield is stable, and the beneficiation production cost and the ironmaking cost are continuously reduced; and the requirement of an existing blast furnace on vanadium-titanium magnetite concentrate materials is met.

Description

Technical Field

[0001] The invention relates to the technical field of three-stage grinding and selection of vanadium-titanium magnetite concentrate, and more specifically, to a three-stage grinding and selection device and method for vanadium-titanium magnetite concentrate. Background Art

[0002] At present, although the original process structure of vanadium-titanium magnetite concentrate production in mineral processing enterprises is reasonable, the on-site process layout is compact and the operation is relatively stable, but with the industry's "fine material policy", green development and the simultaneous promotion of new requirements such as increasing the use of vanadium-titanium magnetite concentrate, the existing blast furnaces have increasingly higher requirements for the quality and output of vanadium-titanium magnetite concentrate; at the same time, as Zhulan Mining enters deep mining, the ore crystal size becomes finer, the grade of the original ore decreases, and the proportion of difficult-to-grind and difficult-to-select ores increases, resulting in an increase in the selection ratio of vanadium-titanium magnetite concentrate year by year, and a decrease in the quality and output of vanadium-titanium magnetite concentrate year by year.

[0003] Affected by the above factors, the contradiction between the quality and output of vanadium-titanium magnetite concentrate of mineral processing enterprises and the smelting production needs of the industry is becoming more and more prominent. Therefore, it is necessary for mineral processing enterprises to take advantage of the current favorable market opportunities to accelerate the transformation of mineral processing technology. At present, with the decreasing grade of mine ore year by year, the quality and output of vanadium-titanium magnetite concentrate produced by the two-stage grinding process are decreasing year by year. The TFe grade of vanadium-titanium magnetite concentrate is 53.6%, and the annual output of vanadium-titanium magnetite concentrate is 4.55 million tons, which is difficult to meet the demand of existing blast furnaces for vanadium-titanium magnetite concentrate materials. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a three-stage grinding device and method for vanadium-titanium magnetite concentrate. Through three-stage grinding, the quality of vanadium-titanium magnetite concentrate can be effectively improved, the quality and stable production of vanadium-titanium magnetite concentrate can be ensured, the ore dressing production cost and ironmaking cost can be continuously reduced, and the demand for vanadium-titanium magnetite concentrate materials of existing blast furnaces can be ensured.

[0005] The present invention provides a three-stage grinding and selection device for vanadium-titanium magnetite concentrate, comprising:

[0006] The ore distribution box is provided with a feed end and a discharge end;

[0007] An upgraded ore pool connected to the feed end;

[0008] A cyclone connected to the discharge end; the cyclone is provided with a tower mill;

[0009] A magnetic separator whose feed inlet is connected to the discharge outlet of the cyclone; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet;

[0010] A filter connected to the magnetic separation outlet; the filter is provided with a concentrate outlet.

[0011] Preferably, the upgraded ore in the upgraded ore pool is vanadium-titanium magnetite concentrate produced by two-stage grinding.

[0012] Preferably, the upgraded ore pools are provided with a plurality of groups, and each group of upgraded ore pools is connected to the feed end via a pipeline.

[0013] Preferably, the cyclones are provided in 6 to 10 groups, and each group of cyclones is connected to the discharge end respectively.

[0014] Preferably, the tower mill and the cyclone form a closed loop; the qualified materials after grinding in the tower mill are classified into a magnetic separator through the cyclone.

[0015] Preferably, the tailings outlet is connected to a tailings conveying system.

[0016] The present invention also provides a three-stage grinding method for vanadium-titanium magnetite concentrate, which adopts the three-stage grinding device for vanadium-titanium magnetite concentrate described in the above technical solution, comprising the following steps:

[0017] The vanadium-titanium magnetite concentrate to be processed is fed into a separation box, and the ground material is then graded and magnetically separated in sequence through a cyclone to obtain tailings and magnetic separation, respectively; wherein the magnetic separation is filtered to obtain the vanadium-titanium magnetite concentrate after three-stage grinding.

[0018] Preferably, the TFe grade of the vanadium-titanium magnetite concentrate to be processed is less than or equal to 54%.

[0019] Preferably, the graded particle size is less than or equal to -325 mesh for subsequent magnetic separation.

[0020] Preferably, it also includes:

[0021] The tailings are concentrated.

[0022] The present invention provides a three-stage grinding and selection device for vanadium-titanium magnetite concentrate, comprising: a separation box; the separation box is provided with a feed end and a discharge end; a quality-improving raw ore pool connected to the feed end; a cyclone connected to the discharge end; the cyclone is provided with a tower mill; a magnetic separator whose feed port is connected to the discharge port of the cyclone; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet; a filter connected to the magnetic separation outlet; the filter is provided with a concentrate outlet. Compared with the prior art, the three-stage grinding and selection device for vanadium-titanium magnetite concentrate provided by the present invention adopts a specific structure and connection relationship to achieve better overall interaction. Through three-stage grinding and selection, the quality of vanadium-titanium magnetite concentrate is effectively improved, ensuring the quality improvement and stable production of vanadium-titanium magnetite concentrate, continuously reducing the ore dressing production cost and ironmaking cost, and ensuring that the demand for vanadium-titanium magnetite concentrate materials of existing blast furnaces is met.

[0023] At the same time, the three-stage grinding and selection method of vanadium-titanium magnetite concentrate provided by the present invention can improve the quality of vanadium-titanium magnetite concentrate, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of a three-stage grinding and selection device for vanadium-titanium magnetite concentrate provided in an embodiment of the present invention;

[0025] Figure 2 It is a curve diagram showing the relationship between grinding fineness and grinding time in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The present invention provides a three-stage grinding and selection device for vanadium-titanium magnetite concentrate, comprising:

[0028] The ore distribution box is provided with a feed end and a discharge end;

[0029] An upgraded ore pool connected to the feed end;

[0030] A cyclone connected to the discharge end; the cyclone is provided with a tower mill;

[0031] A magnetic separator whose feed inlet is connected to the discharge outlet of the cyclone; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet;

[0032] A filter connected to the magnetic separation outlet; the filter is provided with a concentrate outlet.

[0033] The present invention is based on the actual production situation of vanadium-titanium magnet concentrate in mineral processing enterprises, in order to meet the new requirements of innovation and green development in the industry, aiming at the industry's "fine material policy" and the actual situation of increasing the amount of vanadium-titanium magnet concentrate, deeply tapping the internal potential, aiming at the deep mining of Zhulan mining, the ore crystal grain size becomes finer, the grade of the original ore is reduced, the proportion of difficult-to-grind and difficult-to-select ore increases, the selection ratio of vanadium-titanium magnet concentrate increases year by year, and the quality and output of vanadium-titanium magnet concentrate decrease year by year. The present invention actively utilizes the current favorable market opportunities, strives to innovate, and actively promotes the three-stage grinding and selection process transformation of vanadium-titanium magnet concentrate in mineral processing enterprises. The original ore is a vanadium-titanium magnet concentrate produced by two-stage grinding and selection. After fine grinding and selection by the three-stage grinding and selection process, the TFe grade of the vanadium-titanium magnet concentrate of the mineral processing enterprise is increased from 53.6% to more than 55%, and the annual output of vanadium-titanium magnet concentrate is 4.6 million tons, achieving the goal of improving quality and stabilizing production, effectively reducing the production cost of mineral processing enterprises and existing ironmaking plants, creating better economic and social benefits, and having great reference and promotion significance for existing mineral processing enterprises.

[0034] In the present invention, the three-stage grinding and selection device for vanadium-titanium magnetite concentrate comprises: an ore separation box, an ore upgrading pool, a cyclone, a tower mill, a magnetic separator and a filter.

[0035] In the present invention, the separation box is used to collect and aggregate the vanadium-titanium magnetite concentrate to be processed; the separation box is provided with a feed end and a discharge end; wherein the feed end is connected to the upgraded ore pool; and the discharge end is connected to the cyclone.

[0036] In the present invention, the upgraded ore pool is used to receive and store the vanadium-titanium magnetite concentrate to be processed; the upgraded ore in the upgraded ore pool is preferably the vanadium-titanium magnetite concentrate produced by two-stage grinding.

[0037] In the present invention, the raw ore upgrading pools are preferably provided with a plurality of groups, more preferably 4 groups; the groups are connected in parallel with each other, and at the same time, each group of raw ore upgrading pools is connected to the feed end through a pipeline.

[0038] In the present invention, the cyclones are preferably provided in 6 to 10 groups, more preferably 8 groups; the groups are connected in parallel with each other, and each group of cyclones is respectively connected to the discharge end.

[0039] In the present invention, the cyclone is used to classify the material after grinding; the cyclone is provided with a tower mill, and the tower mill is used for grinding.

[0040] In the present invention, the tower mill and the cyclone preferably form a closed loop; the qualified materials after grinding in the tower mill are classified into a magnetic separator through the cyclone for subsequent magnetic separation process.

[0041] In the present invention, the discharge port of the cyclone is connected to the feed port of the magnetic separator; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet; wherein the tailings outlet is preferably connected to a tailings conveying system for subsequent processing of the tailings; the magnetic separation outlet is connected to the filter.

[0042] In the present invention, the filter is used to filter the magnetic ore to obtain the vanadium-titanium magnetite concentrate after three-stage grinding and selection; the filter is provided with a concentrate outlet to discharge the vanadium-titanium magnetite concentrate after three-stage grinding and selection.

[0043] The present invention also provides a three-stage grinding method for vanadium-titanium magnetite concentrate, which adopts the three-stage grinding device for vanadium-titanium magnetite concentrate described in the above technical solution, comprising the following steps:

[0044] The vanadium-titanium magnetite concentrate to be processed is fed into a separation box, and the ground material is then graded and magnetically separated in sequence through a cyclone to obtain tailings and magnetic separation, respectively; wherein the magnetic separation is filtered to obtain the vanadium-titanium magnetite concentrate after three-stage grinding.

[0045] The present invention has no special restriction on the source of the vanadium-titanium magnetite concentrate to be processed, and adopts the vanadium-titanium magnetite concentrate produced by two-stage grinding and selection of a mineral processing enterprise well known to those skilled in the art.

[0046] In the present invention, the TFe grade of the vanadium-titanium magnetite concentrate to be processed is preferably less than or equal to 54%.

[0047] In the present invention, the graded particle size is preferably less than or equal to -325 mesh, and then subsequent magnetic separation is performed.

[0048] In the present invention, the three-stage grinding method for vanadium-titanium magnetite concentrate preferably further comprises:

[0049] The tailings are concentrated.

[0050] The present invention provides a three-stage grinding and selection device and method for vanadium-titanium magnet concentrate. The vanadium-titanium magnet concentrate of mineral processing enterprises is an important raw material for existing blast furnaces. The blast furnaces have increasingly higher requirements for the quality and output of vanadium-titanium magnet concentrate. In order to meet the new requirements of innovation and green development in the industry and ensure that the blast furnaces have "safe food", the present invention aims at the industry's "fine material policy" and the actual increase in the use of vanadium-titanium ferromagnetic concentrate, deeply taps internal potential, and aims at the deep mining of Zhulan Mining, the finer ore crystal particle size, the lower the grade of the original ore, the increase in the proportion of difficult-to-grind and difficult-to-select ore, the annual selection ratio of vanadium-titanium magnet concentrate, and the annual reduction in the grade of vanadium-titanium magnet concentrate. The present invention actively utilizes the current favorable market opportunities, strives to innovate, and actively promotes the quality improvement process transformation of vanadium-titanium magnet concentrate in mineral processing enterprises. The mineral processing enterprise's vanadium-titanium magnet concentrate quality improvement process adopts a new three-stage grinding and selection process. The original ore is the vanadium-titanium magnet concentrate produced by the mineral processing enterprise's two-stage grinding and selection. After fine grinding and selection through the three-stage grinding and selection process, the TFe grade of the vanadium-titanium magnet concentrate is increased from 53.6% to more than 55%. The annual output of vanadium-titanium magnet concentrate is more than 4.6 million tons, thereby reducing the production costs of mineral processing enterprises and existing iron and steel plants, and creating better economic and social benefits for the industry.

[0051] Beneficial effect 1: The vanadium-titanium magnetite concentrate produced by the original two-stage grinding and selection of the mineral processing enterprise is difficult to meet the market production requirements for the output and quality of the vanadium-titanium magnetite concentrate. The present invention changes the two-stage grinding and selection process into a three-stage grinding and selection process, and after fine grinding and selection, the TFe grade of the vanadium-titanium magnetite concentrate is increased from 53.6% to more than 55%, thereby reducing the production cost of the mineral processing enterprise.

[0052] Beneficial effect 2: After the vanadium-titanium magnetite concentrate is upgraded by the mineral processing enterprise, the demand for vanadium-titanium magnetite concentrate by the existing blast furnace is met, thus reducing the cost of ironmaking.

[0053] Beneficial effect 3: Effective measures to implement the industry's carbon peak and carbon neutrality commitments and reduce carbon emissions have achieved good social benefits.

[0054] The experimental results show that through the above-mentioned three-stage grinding and selection device and method of vanadium-titanium magnet concentrate, the TFe grade of vanadium-titanium magnet concentrate of the mineral processing enterprise is increased from 53.6% to more than 55%, which reduces the cost of the entire industrial chain, complies with the industry development strategy, and achieves good economic and social benefits, saving the enterprise 47.426 million yuan annually.

[0055] The present invention provides a three-stage grinding and selection device for vanadium-titanium magnetite concentrate, comprising: a separation box; the separation box is provided with a feed end and a discharge end; a quality-improving raw ore pool connected to the feed end; a cyclone connected to the discharge end; the cyclone is provided with a tower mill; a magnetic separator whose feed port is connected to the discharge port of the cyclone; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet; a filter connected to the magnetic separation outlet; the filter is provided with a concentrate outlet. Compared with the prior art, the three-stage grinding and selection device for vanadium-titanium magnetite concentrate provided by the present invention adopts a specific structure and connection relationship to achieve better overall interaction. Through three-stage grinding and selection, the quality of vanadium-titanium magnetite concentrate is effectively improved, ensuring the quality improvement and stable production of vanadium-titanium magnetite concentrate, continuously reducing the ore dressing production cost and ironmaking cost, and ensuring that the demand for vanadium-titanium magnetite concentrate materials of existing blast furnaces is met.

[0056] In order to further illustrate the present invention, the following examples are provided for detailed description.

[0057] 1. Current status of vanadium-titanium magnetite concentrate production and the necessity of improving quality and stabilizing production:

[0058] The ore dressing enterprises currently mainly process the primary vanadium-titanium magnetite produced from the Zhulan mine, and the grinding and selection system adopts a two-stage grinding and selection process. In order to achieve green and energy-saving development, ore dressing enterprises must actively innovate, constantly explore ways to improve the quality of vanadium-titanium magnetite concentrate and ensure the output of vanadium-titanium magnetite concentrate, actively transform the existing two-stage grinding and selection process, and effectively reduce the production cost of vanadium-titanium magnetite concentrate and ironmaking cost.

[0059] 1.1 Production status of vanadium-titanium magnetite concentrate:

[0060] The vanadium-titanium magnetite concentrate production grinding and selection system of the mineral processing enterprise currently has 16 grinding and selection production series. Currently, it mainly processes the primary vanadium-titanium magnetite produced from the Zhulan mine. The grinding and selection system adopts a two-stage grinding and selection process. The first stage grinding adopts MQG3640 / 3645 / 3650 grid ball mill and Φ660×2 cyclone group (1 in use and 1 spare) to form a closed-circuit grinding. The overflow of the first stage cyclone (-200 mesh content 35~42%) is gravity-flow roughing CTBΦ1230 semi-countercurrent permanent magnet drum magnetic separator, and the roughing concentrate flows by gravity into the second stage cyclone pump pool. The second stage closed circuit grinding adopts MQY2736 / 2740 overflow ball mill, and the grading equipment is Φ350×6 cyclone group (3 in use and 3 in reserve) and high-frequency fine screen. The high-frequency fine screen is used to control and grade the cyclone overflow. The above-screen product is combined with the cyclone underflow and returned to the second stage ball mill for re-grinding. The under-screen product (-200 mesh content 65-70%) enters the selection I and selection II. Selection I adopts CTB1030 / 1230 semi-countercurrent permanent magnetic drum magnetic separator, and selection II adopts CTB1030 / 1230 semi-countercurrent permanent magnetic drum magnetic separator. The tailings of selection I and selection II are combined and fed into scavenging. The scavenging tailings are the final tailings, and the scavenging concentrate is returned to the second stage grinding for re-grinding; the concentrate of selection II is fed into the concentrate pump pool (1-4#) by gravity, and then enters the concentrate first station and is transported to the iron and steel plant through the concentrate pipeline transportation system. Due to the deteriorating properties of ore and the increasing proportion of ore that is difficult to grind and select, mineral processing enterprises process about 13 million t / a of raw ore annually and produce about 4.55 million t / a of vanadium-titanium magnetite concentrate with a TFe grade of 53.6%, which is difficult to meet the demand for vanadium-titanium magnetite concentrate for existing blast furnaces.

[0061] 1.2 Necessity of improving the quality and stabilizing the production of vanadium-titanium magnetite concentrate:

[0062] Climate change is a global problem facing mankind. With the carbon dioxide emissions of various countries, greenhouse gases have soared, posing a threat to life systems. Existing enterprises mainly produce in long processes of blast furnaces and converters. Fossil energy such as coal and coke account for nearly 90% of the energy input for steel production. The carbon emission intensity is about 1.2 times the advanced level. It is difficult to reduce carbon emissions, and there is an urgent need to accelerate the research and development of carbon emission reduction and carbon recycling technologies. After the quality improvement and transformation of mineral processing enterprises is completed, the grade of vanadium-titanium magnet concentrate is expected to increase to more than 55%, which can increase the furnace grade by more than 0.7 percentage points, save about 40,000 tons of coke annually, and reduce carbon dioxide emissions by about 100,000 tons annually. It is an effective measure to implement the industry's commitment to carbon peak and carbon neutrality and reduce carbon emissions.

[0063] In order to improve the core competitiveness in the market, the present invention proposes the "smelting concentrate" policy to improve the blast furnace charge structure, reduce the coke ratio, improve the blast furnace utilization coefficient, reduce the amount of iron ore raw materials purchased from outside, and thus reduce production costs. Production practice has proved that if the grade of TFe raw materials entering the furnace is increased by 1%, the coke ratio will be reduced by 2%, the blast furnace utilization coefficient will be increased by 3%, the quality of vanadium-titanium magnet concentrate will be improved, and the economic benefits will be significant. At the same time, due to the deterioration of ore properties year by year and the increase in the proportion of ore that is difficult to grind and select year by year, the annual processing of raw ore is about 13 million t / a, and the production of vanadium-titanium magnet concentrate with a TFe grade of 53.6% is about 4.55 million t / a, which is difficult to meet the quality and output requirements of existing blast furnaces for vanadium-titanium magnet concentrate materials. It is urgent for mineral processing enterprises to improve the quality of vanadium-titanium magnet concentrate and ensure the output of vanadium-titanium magnet concentrate.

[0064] To sum up, it is very necessary for mineral processing enterprises to implement the transformation of the production process of vanadium-titanium magnetite concentrate. It is a necessary means for the industry to innovate science and technology, improve quality and stabilize production, save energy and reduce consumption, and achieve green development.

[0065] 2. Analysis of difficulties in improving the quality of vanadium-titanium magnetite concentrate:

[0066] As the Zhulan mine has entered deep mining, the properties of the ore have deteriorated year by year. The ilmenite and ilmenite crystal in the vanadium-titanium magnetite are difficult to dissociate into monomers. The existing mineral processing equipment cannot meet the requirements for improving the quality of the vanadium-titanium magnetite concentrate. The existing vanadium-titanium magnetite concentrate output cannot meet the existing blast furnace production needs. The existing vanadium-titanium magnetite concentrate production process must be upgraded and transformed.

[0067] 2.1 The properties of ore deteriorate year by year as the mine enters deep mining:

[0068] According to the actual production situation of the open-pit mine of Panzhihua Iron Mine, the trend of the increasing proportion of difficult-to-grind and difficult-to-select ores in the Zhulan mine will be difficult to reverse for a long period of time in the future. The quality and output of vanadium-titanium magnetite concentrate produced will decline year by year, and the contradiction between supply and demand will increase sharply as the competitive pressure in the steel industry increases. The production of vanadium-titanium magnetite concentrate by mineral processing enterprises is restricted by the conditions of the Zhulan mine. The nature of the incoming ore from the mine is getting worse year by year, the proportion of non-difficult-to-grind and difficult-to-select ores is decreasing year by year, the proportion of difficult-to-grind and difficult-to-select ores is increasing year by year, and the particle size of the ore is getting finer, which has a great impact on the production of vanadium-titanium magnetite concentrate by mineral processing enterprises. In 2021, the incoming ore grade of the Zhulan mine was 28.24%, and the output of vanadium-titanium magnetite concentrate was 4.7753 million tons; in 2022, the incoming ore grade of the Zhulan mine was 28.08%, and the output of vanadium-titanium magnetite concentrate was 4.7459 million tons; in 2023, the incoming ore grade of the Zhulan mine was 27.25%, and the output of vanadium-titanium magnetite concentrate was 4.6732 million tons. The statistical table of mining conditions and production from 2021 to 2023 is shown in the table below.

[0069] Statistics of mining and production from 2021 to 2023

[0070] project 2021 2022 2023 Ore supply (10,000 tons) 1363.64 1363.27 1348.09 Ore grade (%) 28.24 28.08 27.25 Output of vanadium-titanium magnetite concentrate (10,000 tons) 477.53 474.59 467.32

[0071] 2.2 It is difficult for ilmenite and ilmenite crystal in vanadium-titanium magnetite to dissociate into monomers:

[0072] According to the "Experimental Research Report on Improving the Quality and Reducing Impurities in Vanadium-Titanium Magnetite Concentrate" completed by the Institute of Comprehensive Utilization of Mineral Resources, Chinese Academy of Geological Sciences in 2017, the properties of the vanadium-titanium magnetite concentrate currently produced by mineral processing enterprises were analyzed. The grade and main mineral content of the vanadium-titanium magnetite concentrate are shown in the table below.

[0073] Vanadium-titanium magnetite concentrate grade and main mineral content in mineral processing enterprises

[0074]

[0075] Note: Ilmenite refers to the 0.5-5μm ilmenite and ilmenite crystal in the form of lepidolite and platelet in the titanomagnetite. In the MLA test, minerals with an electron beam diameter of >1μm can be quantified. This part of the mineral cannot be dissociated in the mineral processing test. A small amount of amphibole in the gangue is included in the calculation of pyroxene.

[0076] The contents of titanium magnetite, sulfide ore and gangue minerals in the vanadium-titanium magnetite concentrate of the mineral processing enterprise are 78.98%, 1.80% and 6.68% respectively. Magnetic separation mainly recovers titanium magnetite in the vanadium-titanium magnetite concentrate, with a theoretical concentrate grade of 60.00% and a theoretical yield of 78.98%.

[0077] The textured and lamellar 0.5-5μm ilmenite and ilmenite spar (ilmenite type) present in vanadium-titanium magnetite cannot be dissociated as monomers in the mineral processing test. The existing two-stage grinding process is difficult to further improve the quality of vanadium-titanium magnetite concentrate while ensuring the output.

[0078] 2.3 Existing mineral processing equipment cannot meet the quality improvement requirements:

[0079] The grinding and selection system of the mineral processing enterprise adopts a two-stage grinding and selection process. The first stage of grinding uses MQG3640 / 3645 / 3650 grid ball mill and Φ660×2 cyclone group (1 in use and 1 in reserve) to form a closed-circuit grinding. The overflow of the first stage cyclone (-200 mesh content 35-42%) is gravity-flow roughing CTBΦ1230 semi-countercurrent permanent magnetic drum magnetic separator, and the roughing concentrate flows into the second stage cyclone pump pool by gravity. The second stage closed-circuit grinding uses MQY2736 / 2740 overflow ball mill, and the grading equipment is Φ350×6 cyclone group (3 in use and 3 in reserve) and high-frequency fine screen. The quality of the incoming ore from the Zhulan mining field of the mineral processing enterprise has deteriorated year by year, the proportion of ore that is easy to grind and well selected has decreased year by year, the particle size of the concentrate has increased year by year, the time of the concentrate has decreased year by year, and the output and quality of vanadium-titanium magnetite concentrate have also shown a downward trend year by year. If the ore dressing enterprises continue to use the two-stage grinding and selection process, according to the current ore characteristics of the Zhulan mine, the annual output of vanadium-titanium magnetite concentrate is about 4.55 million tons, and the grade of vanadium-titanium magnetite concentrate is 53.6%, which is difficult to meet the demand of the existing blast furnace for vanadium-titanium magnetite concentrate materials. According to the experimental research of the Mining Research Institute and the scientific research team of the ore dressing enterprise, the grade of vanadium-titanium magnetite concentrate of the ore dressing enterprise must reach more than 55%, and the particle size of vanadium-titanium magnetite concentrate minus 325 mesh must reach more than 86%. The current concentrate particle size of the two-stage grinding process cannot meet the quality improvement requirements of vanadium-titanium magnetite concentrate. Therefore, the existing ore dressing equipment cannot meet the quality improvement requirements of vanadium-titanium magnetite concentrate, and the existing grinding and selection equipment must be upgraded. Statistical table of particle size of vanadium-titanium magnetite concentrate from 2021 to 2023.

[0080] Statistics of particle size of vanadium-titanium magnetite concentrate from 20221 to 2023

[0081] project 2021 2022 2023 Ore grade (%) 28.24 28.08 27.25 Concentrate particle size% 64.28 70.84 77.47 Concentrate hourly (tons / hour) 35.8 35.44 34.89

[0082] 3. Measures to improve the quality of vanadium-titanium magnetite concentrate:

[0083] In order to enhance core competitiveness, mineral processing enterprises actively promote scientific and technological research on vanadium-titanium ferromagnetic concentrate and technological transformation of vanadium-titanium magnet concentrate, and continuously improve the quality of vanadium-titanium magnet concentrate on the basis of ensuring the output of vanadium-titanium magnet concentrate. In order to provide reference and basis for the selection of quality-improving mills, mineral processing enterprises commissioned Panzhihua Iron and Steel Research Institute to conduct grindability tests on the quality-improving raw ore. The quality-improving raw ore this time is the vanadium-titanium magnet concentrate produced by the two-stage grinding of the mineral processing enterprise. The vanadium-titanium magnet concentrate of the mineral processing enterprise flows through pipelines to the newly built three-stage grinding and selection system. The three-stage grinding and selection quality-improving process transformation project of the mineral processing enterprise has increased the TFe grade of the vanadium-titanium magnet concentrate of the mineral processing enterprise to more than 55%, with an annual output of 4.6 million tons of vanadium-titanium magnet concentrate, which can reduce the production cost of the entire industrial chain and create better economic and social benefits for the industry.

[0084] 3.1 Carry out industrial tests according to the changes in ore properties:

[0085] In order to provide reference and basis for the selection of quality-enhancing mills, the mineral processing company commissioned Panzhihua Iron and Steel Research Institute to conduct a grindability test on the upgraded ore. The upgraded ore this time was the vanadium-titanium magnetite concentrate produced by the mineral processing company's two-stage grinding process. The vanadium-titanium magnetite concentrate of the mineral processing company flowed by gravity through pipelines to the newly built grinding and selection system.

[0086] In order to strengthen the research on the changes of ore properties and provide reference and basis for the selection of mills for the main equipment of vanadium-titanium magnetite concentrate quality improvement, the ore dressing enterprise commissioned Panzhihua Iron and Steel Research Institute to conduct a grindability test on the upgraded ore. The test ore samples were vanadium-titanium magnetite concentrate of the ore dressing enterprise and the benchmark ore samples for analysis and comparison. The test method was to screen out the -325 mesh particle size of the ore sample and conduct grinding condition tests at different times on the ore sample. The relationship between the grinding time of the ore sample and the -325 mesh content is shown in Figure 2 .

[0087] From the figure, we can find out that the time taken by the mineral processing enterprise to grind the Midi ore sample to -325 mesh content of 86% and the time required for the benchmark ore sample are 22.4min and 18.4min respectively. According to the calculation formula of grindability coefficient.

[0088]

[0089] In the formula: KX: refers to the relative grindability coefficient of the dense ore sample of the mineral processing enterprise; TO: the time required for the dense ore sample of the mineral processing enterprise to be ground to the specified particle size; TX: the time required for the benchmark ore sample to be ground to the specified particle size.

[0090] It can be seen from the relative grindability coefficient that the vanadium-titanium magnetite concentrate of the beneficiation enterprise is more difficult to grind than the benchmark vanadium-titanium magnetite concentrate. The textured and plate-shaped 0.5-5μm ilmenite and ilmenite crystal (ilmenite type) in the titanium magnetite of the beneficiation enterprise cannot be dissociated as a single unit in the beneficiation test. If the beneficiation enterprise wants to improve the quality of the vanadium-titanium magnetite concentrate, it must add a three-stage grinding process to improve the quality of the vanadium-titanium magnetite concentrate.

[0091] Example

[0092] The upgraded ore is the vanadium-titanium magnetite concentrate produced by the two-stage grinding and selection of the mineral processing enterprise, which flows through pipelines to the newly built three-stage grinding and selection device for vanadium-titanium magnetite concentrate.

[0093] The transformation of the three-stage grinding and selection device includes: the plant address is selected 30 meters below the fine grain plant in the roughing operation area of ​​the ore dressing enterprise, where the terrain is open and convenient for plant construction and equipment installation; a new three-stage grinding and selection plant and auxiliary facilities are built, and the three-stage grinding and selection ore is the vanadium-titanium magnetite concentrate produced after the second-stage grinding and selection. The grinding process uses 8 tower mills, with a single motor power of 1120KW.h, and the classification process uses 8 cyclones, model Φ350×11 cyclone group, 8 CTB1230 multi-pole permanent magnetic drum magnetic separators, and the tailings thickening process uses a Φ30m high-efficiency thickener, a large well thickening system, and 8 ZPG72 / 9 double vacuum disc filters in the filtration process. The main equipment table of the three-stage grinding and selection device is shown in Table 1 below.

[0094] Table 1

[0095]

[0096] The production process of the three-stage grinding and selection device provided in the embodiment is divided into 8 grinding and selection series. Figure 1 shown.

[0097] The ore dressing enterprise selects about 53.6% of the vanadium-titanium magnetite concentrate produced by 16 ball mills in the two-stage grinding stage as the upgraded ore for the three-stage grinding system. The vanadium-titanium magnetite concentrate produced by every 4 ball mill systems enters the 1#2#3#4# upgraded ore pool respectively, and then flows to the ore separation box through the pipeline and is evenly distributed to 8 grinding series.

[0098] The ore separation box of the three-stage grinding and selection device of the mineral processing enterprise distributes the upgraded ore evenly to 8 cyclones for classification by pipeline gravity. The upgraded ore with a particle size equal to or less than -325 mesh enters the magnetic separator for sorting, the vanadium-titanium magnetite concentrate enters the filter for filtration to produce vanadium-titanium magnetite concentrate, and the tailings directly enter the tailings conveying system.

[0099] After the upgraded ore is classified by the cyclone in the three-stage grinding and selection device, the upgraded ore with a particle size greater than -325 mesh enters the tower mill for grinding. After grinding, the upgraded ore returns to the cyclone for classification again, forming a closed loop to ensure the classification effect and meet the requirement that the upgraded ore grinding fineness of the three-stage grinding device reaches more than 86% of -325 mesh.

[0100] The three-stage grinding and selection device quality improvement process transformation project provided by the embodiment of the present invention enables the ore dressing enterprise to improve the grinding fineness of the raw ore to more than 86% of the minus 325 mesh, and the TFe grade of the vanadium-titanium magnetite concentrate is increased from 53.6% to more than 55%, and the annual output of vanadium-titanium magnetite concentrate is increased from 4.55 million tons to 4.6 million tons, meeting the requirements and purposes of the three-stage grinding and selection quality improvement process transformation, and taking the vanadium-titanium magnetite concentrate production of the ore dressing enterprise to a new level. The production data comparison table before and after the three-stage grinding and selection device transformation is shown in Table 2 below.

[0101] Table 2

[0102]

[0103]

[0104] The experimental results show that the quality improvement process transformation project implemented by the three-stage grinding and selection device provided in the embodiment of the present invention has increased the particle size of the vanadium-titanium magnetite concentrate of the mineral processing enterprise from 67.69% to 87.81%, and the TFe grade of the vanadium-titanium magnetite concentrate has increased from 53.6% to more than 55%, and the annual output of the vanadium-titanium magnetite concentrate has increased from 4.55 million tons to more than 4.6 million tons, achieving the effect of improving quality and stabilizing production, and effectively reducing the production cost of the vanadium-titanium magnetite concentrate and the ironmaking production cost of the mineral processing enterprise.

[0105] In summary, the present invention provides a three-stage grinding device and method for vanadium-titanium magnet concentrate, and the beneficial effects are as follows: the quality improvement process transformation project implemented by the three-stage grinding device has increased the TFe grade of the vanadium-titanium magnet concentrate of the mineral processing enterprise from 53.6% to more than 55%, reduced the production costs of the mineral processing enterprise and the iron and steel plant, complied with the industry development strategy, and achieved good economic and social benefits; at the same time, the grade of the vanadium-titanium magnet concentrate of the mineral processing enterprise was increased from 53.6% to more than 55%, with an annual output of 4.6 million tons of vanadium-titanium magnet concentrate and an annual profit of 47.426 million yuan.

[0106] Process transformation effect:

[0107] The quality of incoming ore from mineral processing enterprises is getting worse year by year, the proportion of well-grinded and well-selected ores is decreasing year by year, the particle size of concentrate is increasing year by year, the working time of concentrate is decreasing year by year, and the production of vanadium-titanium magnet concentrate is difficult to meet the demand of existing blast furnaces for vanadium-titanium magnet concentrate. The present invention is based on the actual production of the yearly decreasing grade of incoming ore from mines and the two-stage grinding and selection process of vanadium-titanium magnet concentrate, and the current situation that the quality of vanadium-titanium magnet concentrate is low and it is difficult to meet the demand of existing blast furnaces for vanadium-titanium magnet concentrate is low. It is difficult to meet the current demand of vanadium-titanium magnet concentrate, and the difficulties in the quality improvement process of vanadium-titanium magnet concentrate are carefully analyzed. It is proposed to use a three-stage grinding and selection device and method to realize the quality improvement process of vanadium-titanium magnet concentrate, thereby achieving quality improvement and stable production of vanadium-titanium magnet concentrate. From January to October 2024, the mine's ore grade was 25.97%, a decrease of 0.92% from the transformation plan's 26.89%. The particle size of the vanadium-titanium magnetite concentrate increased from 67.69% to 87.81%, an increase of 1.81% from the transformation plan's 86%. The grade of the vanadium-titanium magnetite concentrate reached 55.42%, an increase of 0.42% from the transformation plan's 55%. The output of vanadium-titanium magnetite concentrate was 3.8454 million tons, and the annual output of vanadium-titanium magnetite concentrate was 4.6145 million tons, an increase of 14,500 tons from the transformation plan's 4.6 million tons. The three-stage grinding and selection process transformation effect was achieved, ensuring that the existing blast furnace's demand for vanadium-titanium magnetite concentrate materials was met, and good economic and social benefits were achieved.

[0108] Create benefits:

[0109] Using the prices of raw materials and fuels in the past three years, the production cost of vanadium-titanium magnetite concentrate after upgrading and the cost of pig iron in the whole process of ironmaking are calculated: the grade of vanadium-titanium magnetite concentrate of the ore dressing enterprise is increased from 53.6% to 55%, the profit of vanadium-titanium magnetite concentrate increases by 36.64 yuan / ton, the operating fee of upgrading increases by 33.59 yuan / ton, and the efficiency of upgrading increases by 3.05 yuan / ton; the cost of pig iron in the whole process of ironmaking can be reduced by 7.26 yuan / ton (including: ore cost increases by 5.8 yuan / ton, fuel cost decreases by 13 yuan / ton, and slag reduction reduces cost by 0.06 yuan / ton). The vanadium-titanium magnetite concentrate upgrading and transformation project saves 47.426 million yuan for the enterprise annually.

[0110] The quality of vanadium-titanium magnetite concentrate generates income: the quality of vanadium-titanium magnetite concentrate increases the income by 36.64 yuan / ton;

[0111] Annual revenue from upgrading vanadium-titanium magnetite concentrate: 4.6 million × 36.64 yuan = 168.544 million yuan;

[0112] Upgrading the quality of vanadium-titanium magnetite concentrate to reduce the cost of pig iron: 4.6 million × 7.26 yuan = 33.396 million yuan;

[0113] The operating expenses increased by upgrading the quality of vanadium-titanium magnetite concentrate: 4.6 million × 33.59 yuan = 154.514 million yuan;

[0114] Total benefits after project implementation: 168.544 million yuan + 33.396 million yuan - 154.514 million yuan = 47.426 million yuan.

[0115] 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 apparent to those skilled in the art, and the general principles defined herein may 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 rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A three-stage grinding and selection device for vanadium-titanium magnetite concentrate, characterized in that: include: The ore distribution box is provided with a feed end and a discharge end; An upgraded ore pool connected to the feed end; A cyclone connected to the discharge end; the cyclone is provided with a tower mill; A magnetic separator whose feed inlet is connected to the discharge outlet of the cyclone; the magnetic separator is provided with a tailings outlet and a magnetic separation outlet; A filter connected to the magnetic separation outlet; the filter is provided with a concentrate outlet.

2. The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to claim 1 is characterized in that: The upgraded ore in the upgraded ore pool is vanadium-titanium magnetite concentrate produced by two-stage grinding.

3. The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to claim 1 is characterized in that: The raw ore upgrading pools are provided with a plurality of groups, and each group of raw ore upgrading pools is connected to the feed end through a pipeline.

4. The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to claim 1 is characterized in that: The cyclones are provided in 6 to 10 groups, and each group of cyclones is connected to the discharge end respectively.

5. The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to claim 1 is characterized in that: The tower mill and the cyclone form a closed loop; the qualified materials after grinding in the tower mill are classified into a magnetic separator through the cyclone.

6. The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to claim 1 is characterized in that: The tailings outlet is connected to the tailings conveying system.

7. A three-stage grinding method for vanadium-titanium magnetite concentrate, characterized in that: The three-stage grinding and selection device for vanadium-titanium magnetite concentrate according to any one of claims 1 to 6 comprises the following steps: The vanadium-titanium magnetite concentrate to be processed is fed into a separation box, and the ground material is then graded and magnetically separated in sequence through a cyclone to obtain tailings and magnetic separation, respectively; wherein the magnetic separation is filtered to obtain the vanadium-titanium magnetite concentrate after three-stage grinding.

8. The three-stage grinding method for vanadium-titanium magnetite concentrate according to claim 7 is characterized in that: The TFe grade of the vanadium-titanium magnetite concentrate to be processed is less than or equal to 54%.

9. The three-stage grinding method for vanadium-titanium magnetite concentrate according to claim 7, characterized in that: The classified particle size is less than or equal to -325 mesh particle size for subsequent magnetic separation.

10. The three-stage grinding method for vanadium-titanium magnetite concentrate according to any one of claims 7 to 9, characterized in that: Also includes: The tailings are concentrated.

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