Preparation method of high-titanium vanadium-titanium sinter

Abstract

The invention belongs to the field of metallurgy, and particularly relates to a preparation method of high-titanium vanadium-titanium sinter, which comprises the following steps: a) mixing and digesting active lime and water to obtain slaked lime; b) mixing high-iron low-silicon fine ore, part of slaked lime, part of limestone and water to obtain a first mixture; c) mixing high-titanium vanadium titano-magnetite concentrate, high-silicon low-iron fine ore, fuel, the balance of slaked lime, the balance of limestone, sintering return mine and water to obtain a second mixture; d) mixing and granulating the first mixture, the second mixture and water to obtain a to-be-sintered material, and e) loading the to-be-sintered material into a sintering device, and then performing ignition and air draft sintering to obtain the high-titanium vanadium-titanium sinter. The method provided by the invention can obviously improve the quality of the vanadium-titanium sinter and improve the yield.

Description

Technical Field

[0001] This invention belongs to the field of metallurgy, and particularly relates to a method for preparing high-titanium vanadium-titanium sinter. Background Technology

[0002] Because iron and titanium are closely interdependent in Panzhihua iron ore, grinding during the beneficiation process cannot effectively separate them. Most of the titanium exists in the form of ilmenite and enters the concentrate along with the iron, forming vanadium-titanium magnetite concentrate. When this raw material is used in sintering, it is found that the particle size of the sintering mixture deteriorates, sintering becomes difficult, and the pulverization rate is high. The proportion of self-produced ore returned and blast furnace ore returned reaches about 40%. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a method for preparing high-titanium vanadium-titanium sinter. The method provided by this invention can significantly improve the quality of vanadium-titanium sinter and increase the yield.

[0004] This invention provides a method for preparing high-titanium vanadium-titanium sinter, comprising the following steps:

[0005] a) Quicklime is mixed with water and slaked to obtain hydrated lime;

[0006] b) Mix high-iron low-silica ore powder, part of the slaked lime, part of limestone and water to obtain the first mixture;

[0007] In step b), the Fe content of the high-iron low-silica ore powder is 60~65wt%, and the SiO2 content is ≤6wt%.

[0008] c) Mix high-titanium vanadium-titanium magnetite concentrate, high-silicon low-iron powder ore, fuel, the remainder of slaked lime, the remainder of limestone, sintered return ore and water to obtain a second mixture;

[0009] In step c), the TiO2 content of the high-titanium vanadium-titanium magnetite concentrate is 8-12 wt%; the Fe content of the high-silicon, low-iron powder is 40-45 wt%, and the SiO2 content is 17-25 wt%.

[0010] Steps b) and c) are not in any particular order;

[0011] In steps a) to c), based on a total mass of 100 parts by weight of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, quicklime, and fuel, the amount of the high-titanium vanadium-titanium magnetite concentrate is 44-48 parts by weight, the amount of high-iron low-silica powder ore is 20-26 parts by weight, the amount of high-silica low-iron powder ore is 8-17 parts by weight, the amount of limestone is 5-8 parts by weight, the amount of quicklime is 4-8 parts by weight, and the amount of fuel is 3-7 parts by weight; the amount of slaked lime in step b) is 60-80 wt% of the total slaked lime, and the amount of limestone in step b) is 60-80 wt% of the total limestone.

[0012] d) Mix the first mixture, the second mixture, and water and granulate to obtain the material to be sintered;

[0013] e) The material to be sintered is loaded into the sintering device, and then ignition and venting sintering are performed to obtain high-titanium vanadium-titanium sintered ore.

[0014] In step e), the ignition temperature of the ignition sintering process is 900~1100℃.

[0015] Preferably, the high-titanium vanadium-titanium magnetite concentrate has an Fe content of 50-60 wt%, a SiO2 content of 2-6 wt%, a CaO content of ≤1 wt%, a MgO content of 2-5 wt%, an Al2O3 content of 2-5 wt%, and a V2O5 content of ≤1 wt%.

[0016] The high-iron low-silica ore powder has a CaO content ≤0.2wt%, an MgO content ≤0.5wt%, and an Al2O3 content ≤2wt%.

[0017] The high-silicon, low-iron ore powder has a CaO content of 1-5 wt%, an MgO content of ≤0.5 wt%, an Al2O3 content of 3-6 wt%, and a TiO2 content of ≤0.5 wt%.

[0018] The limestone contains ≤2wt% SiO2, 45-55wt% CaO, ≤1wt% MgO, and ≤1wt% Al2O3.

[0019] The active lime has a SiO2 content of ≤2wt%, a CaO content of 85~95wt%, and an Al2O3 content of ≤1wt%.

[0020] The fuel is coke powder, which has a SiO2 content of 6-10 wt%, a CaO content of ≤1 wt%, a MgO content of 2-5 wt%, and an Al2O3 content of 3-6 wt%.

[0021] Preferably, the average particle size of the high-titanium vanadium-titanium magnetite concentrate is 0.03–0.07 mm;

[0022] The average particle size of the high-iron low-silica ore powder is 3.5~4.5mm;

[0023] The average particle size of the high-silicon, low-iron ore powder is 3.5~4.5 mm;

[0024] The average particle size of the limestone is 1.5~2.5mm;

[0025] The average particle size of the active lime is 1~1.5 mm;

[0026] The average particle size of the fuel is 2-3 mm.

[0027] Preferably, the amount of sintered return ore is 25-35% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, active lime and fuel.

[0028] Preferably, in steps a) to d), the total amount of water used is 7 to 10% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, active lime, fuel, and sintering return ore.

[0029] Preferably, in step a), the molar ratio of the active lime to water, calculated as CaO, is 1:(1.5~2.5); in step b), the ratio of water consumption to total water consumption is 0.8~1.2 times the mass ratio of the high-iron low-silica ore powder to the total mass ratio of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica ore powder, high-silica low-iron ore powder, limestone, active lime, fuel, and sinter return ore; in step c), the water consumption is 70~90% of the total water consumption after deducting the water consumption in steps a)~b).

[0030] Preferably, in step e), a base material is provided at the bottom of the sintering device, the particle size of the base material is 10~16mm, the thickness of the base material is 15~25mm, and the total thickness of the material layer in the sintering device is 600~900mm.

[0031] Preferably, in step e), the ignition time of the ignition-exhaust sintering is 2-3 minutes; the ignition negative pressure of the ignition-exhaust sintering is 5-8 kPa; the sintering exhaust negative pressure of the ignition-exhaust sintering is 10-16 kPa; and the exhaust flow rate of the ignition-exhaust sintering is 5-15 m³ / s. 3 / min; the vertical sintering speed of the ignition and exhaust sintering is 15~25mm / min.

[0032] Preferably, in step e), after the ignition and evacuation sintering is completed, the sintered product is crushed and screened to obtain high-titanium vanadium-titanium sinter with the required particle size.

[0033] Preferably, the high-titanium vanadium-titanium sinter with the required particle size has a particle size ≥ 5 mm.

[0034] Compared with the prior art, the present invention provides a method for preparing high-titanium vanadium-titanium sinter, comprising the following steps: a) mixing and slaking quicklime with water to obtain hydrated lime; b) mixing high-iron, low-silica ore powder, a portion of the hydrated lime, a portion of limestone, and water to obtain a first mixture; in step b), the high-iron, low-silica ore powder has an Fe content of 60-65 wt% and a SiO2 content of ≤6 wt%; c) mixing high-titanium vanadium-titanium magnetite concentrate, high-silica, low-iron ore powder, fuel, the remainder of the hydrated lime, the remainder of limestone, sinter return ore, and water to obtain a second mixture; in step c), the high-titanium vanadium-titanium magnetite concentrate has a TiO2 content of 8-12 wt%; the high-silica, low-iron ore powder has an Fe content of 40-45 wt% and a SiO2 content of 17-25 wt%; steps b) and c) are not sequential; in steps a) to c), the high-titanium vanadium-titanium magnetite concentrate, high-iron, low-silica ore powder, and high-iron, low-silica ore powder are used in combination. The total amount of fine ore, high-silicon low-iron fine ore, limestone, quicklime, and fuel is 100 parts by weight. The amount of high-titanium vanadium-titanium magnetite concentrate is 44-48 parts by weight, the amount of high-iron low-silicon fine ore is 20-26 parts by weight, the amount of high-silicon low-iron fine ore is 8-17 parts by weight, the amount of limestone is 5-8 parts by weight, the amount of quicklime is 4-8 parts by weight, and the amount of fuel is 3-7 parts by weight. The steps... b) The amount of hydrated lime used in step b) is 60-80 wt% of the total amount of hydrated lime, and the amount of limestone used in step b) is 60-80 wt% of the total amount of limestone; d) The first mixture, the second mixture and water are mixed and granulated to obtain the material to be sintered; e) The material to be sintered is loaded into a sintering device and then ignited and ventilated for sintering to obtain high-titanium vanadium-titanium sinter; in step e), the ignition temperature of the ignition and ventilated for sintering is 900-1100℃. This invention improves vanadium-titanium sinter quality by pre-mixing high-iron, low-silica ore powder with flux (hydrated lime, limestone), increasing the contact interface between Fe2O3 and CaO, generating more high-quality calcium ferrite phase, and improving the calcium ferrite content in vanadium-titanium sinter. Furthermore, pre-mixing high-titanium vanadium-titanium concentrate, high-silica, low-iron ore powder, and fuel increases the amount of low-melting-point SiO2-containing phase, which encapsulates and binds the high-titanium vanadium-titanium concentrate particles, increasing the content of the low-melting-point phase. Simultaneously, it reduces the contact between TiO2 and CaO, decreasing the formation of perovskite phases. The presence of SiO2 also promotes the formation of acicular calcium ferrite, further improving sinter quality. By appropriately lowering the ignition temperature and adjusting the fuel ratio, the low-temperature sintering process of vanadium-titanium ore can be controlled while ensuring sufficient liquid phase volume during sintering, thus reducing sintering costs. The method provided by this invention can significantly improve the quality of vanadium-titanium sinter and increase the yield. Detailed Implementation

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] This invention provides a method for preparing high-titanium vanadium-titanium sinter, characterized by comprising the following steps:

[0037] a) Quicklime is mixed with water and slaked to obtain hydrated lime;

[0038] b) Mix high-iron low-silica ore powder, part of the slaked lime, part of limestone and water to obtain the first mixture;

[0039] c) Mix high-titanium vanadium-titanium magnetite concentrate, high-silicon low-iron powder ore, fuel, the remainder of slaked lime, the remainder of limestone, sintered return ore and water to obtain a second mixture;

[0040] Steps b) and c) are not in any particular order;

[0041] d) Mix the first mixture, the second mixture, and water to obtain the material to be sintered;

[0042] e) The material to be sintered is loaded into the sintering device, and then ignition and venting sintering are performed to obtain high-titanium vanadium-titanium sinter.

[0043] In the preparation method provided by the present invention, the raw materials are first prepared, including high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, active lime, fuel, sintering return ore and water.

[0044] In the preparation method provided by this invention, the Fe content of the high-titanium vanadium-titanium magnetite concentrate is preferably 50-60 wt%, more preferably 53-57 wt%, specifically 55.88 wt%; the SiO2 content of the high-titanium vanadium-titanium magnetite concentrate is preferably 2-6 wt%, more preferably 3-5 wt%, specifically 4.01 wt%; the CaO content of the high-titanium vanadium-titanium magnetite concentrate is preferably ≤1 wt%, more preferably 0.4-0.6 wt%, specifically 0.53 wt%; the MgO content of the high-titanium vanadium-titanium magnetite concentrate is preferably 2-5 wt%, more preferably 2.5-4 wt%, specifically 3.18 wt%. The Al2O3 content of the high-titanium vanadium-titanium magnetite concentrate is preferably 2-5 wt%, more preferably 2.5-4 wt%, and specifically 3.56 wt%; the V2O5 content of the high-titanium vanadium-titanium magnetite concentrate is preferably ≤1 wt%, more preferably 0.4-0.8 wt%, and specifically 0.69 wt%; the TiO2 content of the high-titanium vanadium-titanium magnetite concentrate is preferably 8-12 wt%, more preferably 9-11 wt%, and specifically 10.19 wt%; the average particle size of the high-titanium vanadium-titanium magnetite concentrate is preferably 0.03-0.07 mm, more preferably 0.04-0.05 mm, and specifically 0.043 mm.

[0045] In the preparation method provided by the present invention, the Fe content of the high-iron low-silica powder ore is preferably 60-65 wt%, more preferably 62-64 wt%, and specifically 63.5 wt%; the SiO2 content of the high-iron low-silica powder ore is preferably ≤6 wt%, more preferably 3-5 wt%, and specifically 4 wt%; the CaO content of the high-iron low-silica powder ore is ≤0.2 wt%, more preferably 0.05-0.15 wt%, and specifically 0.1 wt%; the MgO content of the high-iron low-silica powder ore is preferably ≤0.5 wt%, more preferably 0.1-0.3 wt%, and specifically 0.2 wt%; the Al2O3 content of the high-iron low-silica powder ore is preferably ≤2 wt%, more preferably 1-1.8 wt%, and specifically 1.6 wt%; the average particle size of the high-iron low-silica powder ore is preferably 3.5-4.5 mm, more preferably 4-4.2 mm, and specifically 4.146 mm.

[0046] In the preparation method provided by this invention, the Fe content of the high-silicon, low-iron powder ore is preferably 40-45 wt%, more preferably 41-43 wt%, and specifically 42 wt%; the SiO2 content of the high-silicon, low-iron powder ore is preferably 17-25 wt%, more preferably 20-22 wt%, and specifically 21 wt%; the CaO content of the high-silicon, low-iron powder ore is preferably 1-5 wt%, more preferably 2-4 wt%, and specifically 3 wt%; the MgO content of the high-silicon, low-iron powder ore is preferably ≤0.5 wt%. More preferably, the content of Al2O3 in the high-silicon, low-iron powder is 0.3-0.45 wt%, specifically 0.39 wt%; the content of TiO2 in the high-silicon, low-iron powder is preferably 3-6 wt%, more preferably 4-5 wt%, specifically 4.47 wt%; the content of TiO2 in the high-silicon, low-iron powder is preferably ≤0.5 wt%, more preferably 0.3-0.4 wt%, specifically 0.35 wt%; the average particle size of the high-silicon, low-iron powder is preferably 3.5-4.5 mm, more preferably 4-4.2 mm, specifically 4.109 mm.

[0047] In the preparation method provided by the present invention, the SiO2 content of the limestone is preferably ≤2wt%, more preferably 1.2~1.6wt%, and specifically 1.4wt%; the CaO content of the limestone is preferably 45~55wt%, more preferably 49~53wt%, and specifically 51.79wt%; the MgO content of the limestone is preferably ≤1wt%, more preferably 0.4~0.8wt%, and specifically 0.61wt%; the Al2O3 content of the limestone is preferably ≤1wt%, more preferably 0.6~0.8wt%, and specifically 0.71wt%; the average particle size of the limestone is preferably 1.5~2.5mm, more preferably 2~2.3mm, and specifically 2.195mm.

[0048] In the preparation method provided by the present invention, the SiO2 content of the activated lime is preferably ≤2wt%, more preferably 1.4~1.8wt%, and specifically 1.6wt%; the CaO content of the activated lime is preferably 85~95wt%, more preferably 88~92wt%, and specifically 90wt%; the Al2O3 content of the activated lime is preferably ≤1wt%, more preferably 0.5~0.9wt%, and specifically 0.7wt%; the average particle size of the activated lime is preferably 1~1.5mm, more preferably 1.2~1.4mm, and specifically 1.375mm.

[0049] In the preparation method provided by the present invention, the fuel is preferably coke powder; the SiO2 content of the coke powder is preferably 6~10wt%, more preferably 8~9wt%, specifically 8.5wt%; the CaO content of the coke powder is preferably ≤1wt%, more preferably 0.3~0.7wt%, specifically 0.5wt%; the MgO content of the coke powder is preferably 2~5wt%, more preferably 2.5~4wt%, specifically 3wt%; the Al2O3 content of the coke powder is preferably 3~6wt%, more preferably 4~5wt%, specifically 4.3wt%; the average particle size of the fuel is preferably 2~3mm, more preferably 2.3~2.7mm, specifically 2.491mm.

[0050] In the preparation method provided by this invention, based on a total mass of 100 parts by weight of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, active lime, and fuel, the preferred mass of the high-titanium vanadium-titanium magnetite concentrate is 44-48 parts by weight, specifically 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, or 48 parts by weight; the preferred mass of the high-iron low-silica powder ore is 20-26 parts by weight, specifically 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, or 26 parts by weight; the preferred mass of the high-silica low-iron powder ore is... The preferred amount is 8-17 parts by mass, specifically 8, 9, 10, 11, 12, 13, 14, 15, 16, or 17 parts by mass; the preferred amount of limestone is 5-8 parts by mass, specifically 5, 5.5, 6, 6.5, 7, 7.5, or 8 parts by mass; the preferred amount of active lime is 4-8 parts by mass, specifically 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, or 8 parts by mass; the preferred amount of fuel is 3-7 parts by mass, specifically 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, or 7 parts by mass.

[0051] In the preparation method provided by this invention, the sintered return ore refers to the fine particles with substandard particle size generated during the sintering process, generally particles with a particle size of <5mm, which are recycled as raw materials in the sintering process to avoid resource waste.

[0052] In the preparation method provided by the present invention, the amount of sintered return ore is preferably 25-35% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, quicklime and fuel, specifically 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34% or 35%.

[0053] In the preparation method provided by the present invention, the total amount of water is preferably 7-10% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, quicklime, fuel and sinter return ore, specifically 7%, 7.2%, 7.5%, 7.7%, 8%, 8.2%, 8.5%, 8.7%, 9%, 9.2%, 9.5%, 9.7% or 10%.

[0054] In the preparation method provided by the present invention, in step a), the molar ratio of the active lime to water, calculated as CaO, is preferably 1:(1.5~2.5), specifically 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.1, 1:2.2, 1:2.3, 1:2.4 or 1:2.5.

[0055] In the preparation method provided by the present invention, in step a), the digestion temperature is preferably 8 to 15 min, specifically 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min or 15 min.

[0056] In the preparation method provided by the present invention, in step b), the amount of hydrated lime is preferably 60-80 wt% of the total amount of hydrated lime, specifically 60 wt%, 62 wt%, 65 wt%, 67 wt%, 70 wt%, 72 wt%, 75 wt%, 77 wt%, or 80 wt%; the amount of limestone is preferably 60-80 wt% of the total amount of limestone, specifically 60 wt%, 62 wt%, 65 wt%, 67 wt%, 70 wt%, 72 wt%, 75 wt%, 77 wt%, or 80 wt%.

[0057] In the preparation method provided by the present invention, the ratio of water consumption in step b) to the total water consumption is preferably 0.8 to 1.2 times the mass ratio of the high-iron low-silica powder ore to the total mass ratio of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, active lime, fuel and sintering return ore. Specifically, it can be 0.8 times, 0.85 times, 0.9 times, 0.95 times, 1 time, 1.05 times, 1.1 times, 1.15 times or 1.2 times.

[0058] In the preparation method provided by the present invention, in step b), the mixing temperature is preferably 10~40℃, specifically 10℃, 15℃, 20℃, 25℃ (room temperature), 30℃, 35℃ or 40℃; the mixing time is preferably 4~8min, specifically 4min, 4.5min, 5min, 5.5min, 6min, 6.5min, 7min, 7.5min or 8min.

[0059] In the preparation method provided by the present invention, the amount of water used in step c) is preferably 70-90% of the remaining water after deducting the water used in steps a) to b) from the total amount of water. Specifically, it can be 70%, 72%, 75%, 77%, 80%, 82%, 85%, 87% or 90% of the remaining water.

[0060] In the preparation method provided by the present invention, in step c), the mixing temperature is preferably 10~40℃, specifically 10℃, 15℃, 20℃, 25℃ (room temperature), 30℃, 35℃ or 40℃; the mixing time is preferably 4~8min, specifically 4min, 4.5min, 5min, 5.5min, 6min, 6.5min, 7min, 7.5min or 8min.

[0061] In the preparation method provided by the present invention, in step d), the mixing and granulation temperature is preferably 10~40℃, specifically 10℃, 15℃, 20℃, 25℃ (room temperature), 30℃, 35℃ or 40℃; the mixing and granulation time is preferably 4~8min, specifically 4min, 4.5min, 5min, 5.5min, 6min, 6.5min, 7min, 7.5min or 8min.

[0062] In the preparation method provided by the present invention, in step d), after the mixing and granulation, the particle size of the sintering material is preferably 2-7 mm, specifically 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm or 7 mm.

[0063] In the preparation method provided by the present invention, in step e), the bottom of the sintering device is preferably provided with a base material; the particle size of the base material is preferably 10-16 mm, specifically 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm or 16 mm; the thickness of the base material is preferably 15-25 mm, specifically 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm or 25 mm; the total thickness of the material layer in the sintering device is preferably 600-900 mm, specifically 600 mm, 620 mm, 650 mm, 670 mm, 700 mm, 720 mm, 750 mm, 770 mm, 800 mm, 820 mm, 850 mm, 870 mm or 900 mm.

[0064] In the preparation method provided by this invention, in step e), the ignition temperature for the ignition-induced sintering is preferably 900~1100℃, specifically 900℃, 920℃, 950℃, 970℃, 1000℃, 1020℃, 1050℃, 1070℃, or 1100℃; the ignition time for the ignition-induced sintering is preferably 2~3 min, specifically 2 min, 2.5 min, or 3 min; the ignition negative pressure for the ignition-induced sintering is preferably 5~8 kPa, specifically 5 kPa, ... The sintering exhaust negative pressure for ignition and exhaust sintering is preferably 10~16 kPa, specifically 10 kPa, 10.5 kPa, 11 kPa, 11.5 kPa, 12 kPa, 12.5 kPa, 13 kPa, 13.5 kPa, 14 kPa, 14.5 kPa, 15 kPa, 15.5 kPa, or 16 kPa; the exhaust flow rate for ignition and exhaust sintering is preferably 5~15 m³ / s. 3 / min, specifically 5m 3 / min, 6m 3 / min, 7m 3 / min, 8m 3 / min, 9m 3 / min, 10m 3 / min, 11m 3 / min, 12m 3 / min, 13m 3 / min, 14m 3 / min or 15m 3 / min; the vertical sintering speed of the ignition and exhaust sintering is preferably 15~25mm / min, specifically 15mm / min, 16mm / min, 17mm / min, 18mm / min, 19mm / min, 20mm / min, 21mm / min, 22mm / min, 23mm / min, 24mm / min or 25mm / min.

[0065] In the preparation method provided by this invention, in step e), after the ignition and exhaust sintering is completed, the sintered product is preferably crushed and sieved to obtain high-titanium vanadium-titanium sinter with a particle size meeting the requirements. In this invention, the method for determining the end of sintering is: when the exhaust gas temperature in the exhaust pipe at the lower end of the sintering device rises to its highest point and then drops to 20°C, sintering is considered complete. In this invention, the crushing method is preferably: first, coarse crushing is performed in a crusher, followed by several drops; wherein, the spacing between the crushers is preferably 40~60mm, specifically 50mm; the drop height of the drops is preferably 1~3m, specifically 2m; the number of drops is preferably 2~5 times, specifically 3 times; and the particle size of the high-titanium vanadium-titanium sinter with the required particle size is preferably ≥5mm.

[0066] For clarity, the following examples and comparative models will be used to provide a detailed description.

[0067] Example 1

[0068] Step 1: Prepare the raw materials, including: high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, quicklime, coke powder, sintering return ore, and water; the chemical composition and particle size distribution of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, quicklime, and coke powder are shown in Tables 1-2; based on a total usage of 100wt% for the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica powder ore, high-silica low-iron powder ore, limestone, quicklime, and coke powder, the usage of the high-titanium vanadium-titanium magnetite concentrate is 47.5wt%, and the usage of the high-iron low-silica powder ore is... The total amount of water used is 25 wt%, high-silicon low-iron ore powder is 10 wt%, limestone is 6.5 wt%, quicklime is 6 wt%, and coke powder is 5 wt%. The sintering return ore is particles with a particle size <5 mm generated during the previous batch of sintering ore production, and its amount is 30 wt% of the total mass of high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon ore powder, high-silicon low-iron ore powder, limestone, quicklime, and coke powder. The total water consumption is 8 wt% of the total mass of high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon ore powder, high-silicon low-iron ore powder, limestone, quicklime, coke powder, and sintering return ore.

[0069] Table 1 Chemical composition of raw materials used in sintering (unit: wt%)

[0070]

[0071] Table 2 Particle size composition of raw materials used in sintering (unit: wt%)

[0072]

[0073] Step 2: Add water to the quicklime for digestion. The molar ratio of quicklime to water (calculated as CaO) is 1:2, and the digestion time is 10 minutes to obtain slaked lime.

[0074] Step 3: Put high-iron low-silica ore powder, 70wt% hydrated lime and 70wt% limestone into a strong mixer and add water to mix. The proportion of water added in the total water volume is consistent with the proportion of high-iron low-silica ore powder in the total mass of high-titanium vanadium-titanium magnetite concentrate, high-iron low-silica ore powder, high-silica low-iron ore powder, limestone, quicklime, fuel and sinter return ore. The mixing temperature is room temperature and the mixing time is 5 minutes to form mixture 1.

[0075] Step 4: Mix high-titanium vanadium-titanium magnetite concentrate, high-silicon low-iron powder, coke powder, 30wt% hydrated lime, 30wt% limestone and return ore with water. The amount of water added is 80wt% of the remaining total water. The mixing temperature is room temperature and the mixing time is 5min to form mixture 2.

[0076] Step 5: Place mixture 1 and mixture 2 into a two-stage mixing drum mill for granulation, and add the remaining moisture. The granulation temperature is room temperature, and the granulation time is 5 minutes to obtain a sintering material with a particle size of 3.5 mm.

[0077] Step 6: Load the material to be sintered into the sintering cup (300mm in diameter and 1000mm in height). The sintering cup is pre-laid with a base material (15mm in particle size and 20mm in thickness). The total thickness of the material layer in the sintering cup is 800mm (including the thickness of the base material).

[0078] Step 7: Ignite and sinter the material in the sintering cup using a vacuum sintering system. The ignition temperature is 1000℃, the ignition time is 2 minutes, the ignition negative pressure is 6.0 kPa, the sintering vacuum negative pressure is 12.0 kPa, and the vacuum flow rate is 10 m³ / s. 3 / min, used to control the vertical sintering speed at 20mm / min.

[0079] Step 8: When the exhaust gas temperature in the lower exhaust duct of the sintering cup rises to its highest point and then drops to 20°C, the sintering process ends. The sintered cake is poured out and coarsely crushed (crusher spacing 50mm). After three drops (drop height 2m), it is screened according to the following sizes: 40~25mm, <25~16mm, <16~10mm, <10~5mm, <5mm. The mass percentage of particles ≥5mm is calculated (i.e., yield). The drum strength is tested according to the standard requirements.

[0080] Performance test results show that the sinter has a TFe grade of 49.38 wt%, CaO content of 13.15 wt%, SiO2 content of 6.32 wt%, TiO2 content of 5.31 wt%, sinter basicity of CaO / SiO2 = 2.08 times, sinter drum strength of 63.72%, and yield of 76.71%.

[0081] Example 2

[0082] Referring to Example 1, the only difference is that, based on a total usage of 100wt% of high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, quicklime, and coke powder, the usage of high-titanium vanadium-titanium magnetite concentrate is 45wt%, high-iron low-silicon powder ore is 22wt%, high-silicon low-iron powder ore is 15wt%, limestone is 7wt%, quicklime is 6wt%, and coke powder is 5wt%.

[0083] Performance testing results show that the sinter has a TFe grade of 48.29%, CaO content of 14.36 wt%, SiO2 content of 6.87 wt%, TiO2 content of 4.96 wt%, sinter basicity of CaO / SiO2 = 2.09 times, sinter drum strength of 66.25%, and yield of 80.27%.

[0084] Comparative Example 1

[0085] Referring to Example 1, the only difference is that, based on a total usage of 100wt% of high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon powder ore, high-silicon low-iron powder ore, limestone, quicklime, and coke powder, the usage of high-titanium vanadium-titanium magnetite concentrate is 50wt%, high-iron low-silicon powder ore is 28wt%, high-silicon low-iron powder ore is 5wt%, limestone is 6wt%, quicklime is 6wt%, and coke powder is 5wt%.

[0086] Performance test results show that the sinter has a TFe grade of 50.54%, CaO content of 12.20%, SiO2 content of 5.80wt%, TiO2 content of 5.70wt%, sinter basicity of CaO / SiO2 = 2.10 times, sinter drum strength of 61.50%, and yield of 73.54%.

[0087] Based on the results of the above embodiments and comparative examples, the method of this invention can enable the sintered ore obtained from the sintering of high-titanium vanadium-titanium magnetite concentrate to achieve better technical indicators, meeting the requirements of vanadium-titanium ore blast furnace smelting. Moreover, the technical indicators of the sintered ore in the embodiments are better than those in the comparative examples, showing a significant improvement effect.

[0088] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing high-titanium vanadium-titanium sinter, characterized in that, The method comprises the following steps: a) mixing active lime with water to obtain slaked lime; b) mixing high-iron low-silicon ore, part of the slaked lime, part of limestone and water to obtain a first mixture; In step b), the Fe content of the high-iron low-silicon ore is 60-65 wt%, and the SiO2 content is ≤6 wt%; c) mixing high-titanium vanadium-titanium magnetite concentrate, high-silicon low-iron ore, fuel, the balance of the slaked lime, the balance of limestone, sintered return ore and water to obtain a second mixture; In step c), the TiO2 content of the high-titanium vanadium-titanium magnetite concentrate is 8-12 wt%; the Fe content of the high-silicon low-iron ore is 40-45 wt%, and the SiO2 content is 17-25 wt%; Steps b) and c) have no sequence; In steps a) to c), based on the total amount of 100 parts by mass of the high-titanium vanadium-titanium magnetite concentrate, high-iron low-silicon ore, high-silicon low-iron ore, limestone, active lime and fuel, the amount of the high-titanium vanadium-titanium magnetite concentrate is 44-48 parts by mass, the amount of the high-iron low-silicon ore is 20-26 parts by mass, the amount of the high-silicon low-iron ore is 8-17 parts by mass, the amount of the limestone is 5-8 parts by mass, the amount of the active lime is 4-8 parts by mass, and the amount of the fuel is 3-7 parts by mass; the amount of the slaked lime in step b) is 60-80 wt% of the total amount of slaked lime, and the amount of the limestone in step b) is 60-80 wt% of the total amount of limestone; d) mixing the first mixture, the second mixture and water to obtain a sintering material; e) loading the sintering material into a sintering device, and then igniting and sintering to obtain high-titanium vanadium-titanium sinter; In step e), the ignition temperature of the ignition and sintering is 900-1100℃.

2. The production method according to claim 1, characterized by, The high-titanium vanadium-titanium magnetite concentrate has a Fe content of 50-60 wt%, a SiO2 content of 2-6 wt%, a CaO content of ≤1 wt%, a MgO content of 2-5 wt%, an Al2O3 content of 2-5 wt%, and a V2O5 content of ≤1 wt%; The high-iron low-silicon ore has a CaO content of ≤0.2 wt%, a MgO content of ≤0.5 wt%, and an Al2O3 content of ≤2 wt%; The high-silicon low-iron ore has a CaO content of 1-5 wt%, a MgO content of ≤0.5 wt%, an Al2O3 content of 3-6 wt%, and a TiO2 content of ≤0.5 wt%; The limestone has a SiO2 content of ≤2 wt%, a CaO content of 45-55 wt%, a MgO content of ≤1 wt%, and an Al2O3 content of ≤1 wt%; The active lime has a SiO2 content of ≤2 wt%, a CaO content of 85-95 wt%, and an Al2O3 content of ≤1 wt%; The fuel is coke powder, and the coke powder has a SiO2 content of 6-10 wt%, a CaO content of ≤1 wt%, a MgO content of 2-5 wt%, and an Al2O3 content of 3-6 wt%.

3. The preparation method according to claim 1, characterized in that, The average particle size of the high-titanium vanadium-titanium magnetite concentrate is 0.03-0.07 mm. The average particle size of the high-iron low-silicon ore powder is 3.5-4.5 mm. The average particle size of the high-iron low-silicon ore powder is 3.5-4.5 mm. The average particle size of the limestone is 1.5-2.5 mm. The average particle size of the active lime is 1-1.5 mm. The average particle size of the fuel is 2-3 mm.

4. The method of claim 1, wherein, The amount of the sintered return ore is 25-35% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, the high-iron low-silicon ore powder, the high-silicon low-iron ore powder, the limestone, the active lime and the fuel.

5. The preparation method according to claim 1, characterized in that, The total amount of water in steps a)-d) is 7-10% of the total mass of the high-titanium vanadium-titanium magnetite concentrate, the high-iron low-silicon ore powder, the high-silicon low-iron ore powder, the limestone, the active lime, the fuel and the sintered return ore.

6. The preparation method according to claim 5, characterized in that, In step a), the molar ratio of the active lime to water (calculated as CaO) is 1:(1.5-2.5); in step b), the ratio of the amount of water used to the total amount of water is 0.8-1.2 times the ratio of the mass of the high-iron low-silicon ore powder to the total mass of the high-titanium vanadium-titanium magnetite concentrate, the high-iron low-silicon ore powder, the high-silicon low-iron ore powder, the limestone, the active lime, the fuel and the sintered return ore; in step c), the amount of water used is 70-90% of the remaining water after the water used in steps a)-b) is removed from the total amount of water.

7. The preparation method according to claim 1, characterized in that, In step e), the bottom of the sintering device is provided with a bottom material, the particle size of the bottom material is 10-16 mm, and the thickness of the bottom material is 15-25 mm; the total thickness of the material layer in the sintering device is 600-900 mm.

8. The method of claim 1, wherein, In step e), the ignition time of the ignition suction sintering is 2-3 min; the ignition negative pressure of the ignition suction sintering is 5-8 kPa; the sintering suction negative pressure of the ignition suction sintering is 10-16 kPa; the suction flow of the ignition suction sintering is 5-15 m 3 / min; and the vertical sintering speed of the ignition suction sintering is 15-25 mm / min.

9. The method of claim 1, wherein, In step e), after the ignition and exhaust sintering is completed, the sintered product is crushed and sieved to obtain a high-titanium vanadium-titanium sinter with a particle size meeting the requirements.

10. The method of claim 9, wherein, The particle size of the high-titanium vanadium-titanium sinter with a particle size meeting the requirements is ≥5 mm.

Images