Blast furnace smelting method for high-proportion vanadium-titanium pellets

Abstract

The invention belongs to the field of blast furnace ironmaking, and particularly relates to a high-proportion vanadium-titanium pellet blast furnace smelting method which comprises the following steps: blast furnace ore and coke fall into a blast furnace throat through a material distribution device of a blast furnace for blast furnace smelting to obtain molten iron and furnace slag; the blast furnace throat is equally divided into ten gears from an annular area, and the first gear to the tenth gear are sequentially arranged from the original point of the center of the blast furnace throat from inside to outside. The drop point of the blast furnace ore is in the area from the fourth gear to the eighth gear, and the drop point of the coke is in the area from the second gear to the ninth gear. The method provided by the invention can guide blast furnace reinforced smelting under the condition of high vanadium-titanium pellet matching, realizes low pig iron cost and reduces carbon emission in sintering and ironmaking procedures, and has huge economic benefits and social benefits.

Description

Technical Field

[0001] The invention belongs to the field of blast furnace ironmaking, and in particular relates to a blast furnace smelting method of high-proportion vanadium-titanium pellet ore. Background Art

[0002] The blast furnace smelts high-titanium vanadium-titanium magnetite, and a large amount of vanadium-titanium concentrate is used to produce vanadium-titanium sinter. The sinter has a low drum index, high return rate, and high low-temperature pulverization rate due to the high TiO2 content, which makes the quality of blast furnace raw materials at a low level. The most critical problem is that due to the high proportion of vanadium-titanium ore, the high TiO2 content in the slag, and the high blast furnace slag-iron ratio, the slag not only has poor desulfurization ability but also easily thickens due to the reduction of TiO2. Improving the ore ratio of vanadium-titanium pellets has many benefits. First, the TiO2 that originally entered the blast furnace from the sintering process can be transferred to the pelletizing process, and the TiO2 content of the sintered ore is correspondingly reduced, thereby significantly improving the drum index of the sintered ore. Secondly, the sintering production process uses more coal powder or coke powder as fuel, and the pelletizing process uses coke oven gas as fuel. Improving the pellet ratio can reduce carbon dioxide emissions and other pollutants in the sintering process. Third, increasing the proportion of pelletized ore in blast furnace charge can improve the metallurgical properties and permeability of the charge column.

[0003] Secondly, due to the particularity of vanadium-titanium magnetite, a large amount of CaO, SiO2, MgO, Al2O3 and other slag-forming components need to be added during the blast furnace smelting process to appropriately reduce the TiO2 content of the slag, resulting in low blast furnace entry grade and high slag-iron ratio. For blast furnaces that smelt ordinary ores, the entry grade can reach 58% or even higher, and the slag-iron ratio is less than 300kg / t. The entry grade of Panzhihua Iron and Steel's blast furnace is usually only 50.5%-51.5%, and the slag-iron ratio is as high as 580-650kg / t, which requires a large amount of coke and pulverized coal injection. Coke not only produces a large amount of CO2 during blast furnace smelting, but also produces a large amount of CO2 during the production of coke. The coke ratio of Panzhihua Iron and Steel's blast furnace reaches 420-450kg / t, which is much higher than that of blast furnaces that smelt ordinary ores.

[0004] At present, the proportion of pellets smelted in domestic blast furnaces is generally low. Only a few domestic enterprises such as Shougang Jingtang have a pellet ratio of more than 50%. Moreover, domestic and foreign enterprises that smelt high-proportion pellets use ordinary pellets that do not contain titanium. The high-titanium vanadium-titanium pellets smelted by Panzhihua Iron and Steel's blast furnace have greatly increased the proportion of vanadium-titanium pellets to more than 60%, which is a world first and innovative. However, with the increase in the proportion of pellets, the charge structure, raw material quality, and charge characteristics of blast furnace smelting have undergone relatively obvious changes. The operating system of the blast furnace must make corresponding changes to adapt to these changes after the increase in the proportion of vanadium-titanium pellets. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a blast furnace smelting method for high-proportion vanadium-titanium pellets, which can better match the blast furnace smelting conditions after the vanadium-titanium pellet ratio is increased, and has good economic and environmental benefits.

[0006] The present invention provides a blast furnace smelting method of high-proportion vanadium-titanium pellets, comprising the following process:

[0007] Blast furnace ore and coke fall into the blast furnace throat through the blast furnace's distribution device, and smelting is carried out in the blast furnace to obtain molten iron and slag;

[0008] The effective volume of the blast furnace is 1000-2500m 3 ;

[0009] The blast furnace ore includes vanadium-titanium pellets and sintered ore, the binary basicity of the vanadium-titanium pellets is ≤0.8, the binary basicity of the sintered ore is 2-2.4, and the content of the vanadium-titanium pellets in the blast furnace ore is ≥60wt%;

[0010] The post-reaction strength of the coke is 63-68%;

[0011] The blast furnace throat is divided into 10 gears from the annular area, starting from the center of the throat and going outwards, from the 1st to the 10th gear;

[0012] The blast furnace ore falls within the region of the 4th to 8th gears, the innermost gear is the 4th or 5th gear, the ore mass of the innermost gear does not exceed 10-15% of the total ore mass, the ore mass of the 8th gear is 20-35% of the total ore mass, and the ore mass of the remaining gears decreases from the outside to the inside according to an arithmetic progression;

[0013] The coke is placed in the area of ​​the 2nd to 9th gears, the coke mass of the 2nd gear is 20-35% of the total coke mass, the coke mass of the 9th gear is 20-30% of the total coke mass, and no coke is placed in the 3rd gear; if there is ore in the 4th gear, the coke mass of the 4th to 8th gears is evenly distributed among the gears; if there is no ore in the 4th gear, no coke is placed in the 3rd to 4th gears, and the coke mass of the 5th to 8th gears is evenly distributed among the gears;

[0014] The blast furnace ore and coke have the same feed line in the blast furnace, and the feed line is 1.5 to 2.5 m;

[0015] The oxygen enrichment rate of the blast furnace smelting is 4.5-5.5%, and the ratio of blast kinetic energy to furnace diameter is 18-19 kJ / (s·m 2 ).

[0016] Preferably, the blast kinetic energy is calculated according to formula (1):

[0017]

[0018] In formula (1): Q b The blast volume displayed on the blast furnace instrument, including air and oxygen-rich air with high oxygen content, in m 3 / s;Q O is the oxygen enrichment, unit: m 3 / s;O b is the oxygen content in oxygen-enriched air; s is the air inlet surface of the blast furnace, unit: m 2 ;p a and p b are standard atmospheric pressure and actual blast furnace wind pressure, in kPa; T a and T b The absolute temperatures corresponding to 0°C and hot air temperature, in K.

[0019] Preferably, if the expected TiO2 content of the slag is 23-23.5wt%, the ratio of the blast kinetic energy to the furnace diameter is controlled at 18-18.25 kJ / (s·m 2 );

[0020] If the expected TiO2 content of the slag is >23.5% and ≤24wt%, the ratio of the blast kinetic energy to the furnace diameter is controlled to be >18.25 kJ / (s·m 2 ) and ≤18.5kJ / (s·m 2 );

[0021] If the expected TiO2 content of the slag is greater than 24wt% and less than or equal to 24.5wt%, the ratio of the blast kinetic energy to the furnace diameter is controlled to be greater than 18.5kJ / (s·m 2 ) and ≤18.75kJ / (s·m 2 );

[0022] If the expected TiO2 content of the slag is >24.5wt% and ≤25wt%, the ratio of the blast kinetic energy to the furnace diameter is controlled to be >18.75kJ / (s·m 2 ) and ≤19kJ / (s·m 2 ).

[0023] Preferably, if the effective volume of the blast furnace is 1000-1500m 3 , then use coke with a strength of 63-64% after reaction;

[0024] If the effective volume of the blast furnace is > 1500m 3 and ≤2200m 3 , then use coke with a strength after reaction of >64% and ≤66%;

[0025] If the effective volume of the blast furnace is > 2200m3 and ≤2500m 3 , then use coke with a post-reaction strength of >66% and ≤68%.

[0026] Preferably, the TiO2 content of the vanadium-titanium pellet is 9-12wt%, and the V2O5 content is 0.4-0.8wt%.

[0027] Preferably, the content of vanadium-titanium magnetite concentrate in the raw material for preparing the vanadium-titanium pellets is ≥90wt%.

[0028] Preferably, the raw materials for preparing the vanadium-titanium pellets also include one or more of ordinary iron ore concentrate, slaked lime and bentonite.

[0029] Preferably, the TiO2 content of the sintered ore is ≤1wt%, and the V2O5 content is ≤0.05wt%.

[0030] Preferably, the blast furnace ore has a quality of 50-55%.

[0031] Preferably, the coke ratio of the blast furnace smelting is 380-400 kg / t; the coal ratio of the blast furnace smelting is 125-140 kg / t.

[0032] Compared with the prior art, the present invention provides a blast furnace smelting method for high-proportion vanadium-titanium pellets, which includes the following process: blast furnace ore and coke fall into the blast furnace throat through the blast furnace distribution device, and blast furnace smelting is performed to obtain molten iron and slag; the effective volume of the blast furnace is 1000-2500m 3; The blast furnace ore includes vanadium-titanium pellets and sintered ore, the binary basicity of the vanadium-titanium pellets is ≤0.8, the binary basicity of the sintered ore is 2-2.4, and the content of the vanadium-titanium pellets in the blast furnace ore is ≥60wt%; the post-reaction strength of the coke is 63-68%; the blast furnace throat is divided into 10 gears from the annular area, starting from the center of the throat and outward from the 1st to the 10th gear; the landing point of the blast furnace ore is in the area of ​​the 4th to the 8th gear, the innermost gear is the 4th or 5th gear, the ore mass of the innermost gear does not exceed 10-15% of the total ore mass, the ore mass of the 8th gear is 20-35% of the total ore mass, and the ore mass of the remaining gears is from the outside to the outside. The coke is deposited in the area of ​​the 2nd to 9th gears, the coke mass of the 2nd gear is 20-35% of the total coke mass, the coke mass of the 9th gear is 20-30% of the total coke mass, and no coke is distributed in the 3rd gear; if the 4th gear is equipped with ore, the coke mass of the 4th to 8th gears is evenly distributed in each gear; if there is no ore in the 4th gear, no coke is distributed in the 3rd to 4th gears, and the coke mass of the 5th to 8th gears is evenly distributed in each gear; the ore and coke of the blast furnace are in the same material line in the blast furnace, and the material line is 1.5-2.5m; the oxygen enrichment rate of the blast furnace smelting is 4.5-5.5%, and the ratio of blast kinetic energy to furnace diameter is 18-19kJ / (s·m 2 The method provided by the present invention can guide the blast furnace intensified smelting under the high vanadium titanium pellet ratio, realize low pig iron cost and reduce carbon emissions in sintering and ironmaking processes, and has huge economic and social benefits. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention are described clearly and completely below. 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.

[0034] The present invention provides a blast furnace smelting method of high-proportion vanadium-titanium pellets, comprising the following process:

[0035] Blast furnace ore and coke fall into the blast furnace throat through the blast furnace's distribution device for blast furnace smelting to obtain molten iron and slag.

[0036] In the method provided by the present invention, the effective volume of the blast furnace is 1000-2500m 3 , specifically 1000m 3 、1050m 3 、1100m 3 、1150m 3 、1200m 3、1250m 3 、1300m 3 、1350m 3 、1400m 3 、1450m 3 、1500m 3 、1550m 3 、1600m 3 、1650m 3 、1700m 3 、1750m 3 、1800m 3 、1850m 3 、1900m 3 、1950m 3 , 2000m 3 、2050m 3 、2100m 3 、2150m 3 、2200m 3 、2250m 3 、2300m 3 、2350m 3 、2400m 3 、2450m 3 or 2500m 3 .

[0037] In the method provided by the present invention, the blast furnace ore includes vanadium-titanium pellets and sintered ore; wherein the binary basicity (R2, w(CaO) / w(SiO2)) of the vanadium-titanium pellets is ≤0.8, specifically 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 or 0.8; the TiO2 content of the vanadium-titanium pellets is preferably 9-12wt%, specifically 9wt%, 9.5wt%, 10wt%, 10.5wt%, 11wt%, 11.5wt% or 12wt%; the V2O5 content of the vanadium-titanium pellets is preferably 0.4-0.8wt%, specifically 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.65wt%, 0.7wt%, 0.75wt% or 0.8wt%.

[0038] In the method provided by the present invention, the content of vanadium-titanium magnetite concentrate in the raw material for preparing the vanadium-titanium pellet in the blast furnace ore is preferably ≥90wt%, specifically 90wt%, 91wt%, 92wt%, 93wt%, 94wt%, 95wt%, 96wt%, 97wt%, 98wt% or 99wt%; the raw material for preparing the vanadium-titanium pellet preferably also includes one or more of ordinary iron concentrate, slaked lime and bentonite.

[0039] In the method provided by the present invention, the binary basicity of the sintered ore in the blast furnace ore is 2 to 2.4, specifically 2, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35 or 2.4; the TiO2 content of the sintered ore is preferably ≤1wt%, specifically 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt% or 1wt%; the V2O5 content of the sintered ore is preferably ≤0.05wt%, specifically 0.01wt%, 0.02wt%, 0.03wt%, 0.04wt% or 0.05wt%.

[0040] In the method provided by the present invention, the content of vanadium-titanium pellets in the blast furnace ore is ≥60wt%, preferably 60-70wt%, specifically 60wt%, 61wt%, 62wt%, 63wt%, 64wt%, 65wt%, 66wt%, 67wt%, 68wt%, 69wt% or 70wt%; the grade of the blast furnace ore entering the furnace is preferably 50-55%, specifically 50%, 50.5%, 51%, 51.5%, 52%, 52.5%, 53%, 53.5%, 54%, 54.5% or 55%.

[0041] In the method provided by the present invention, the coke has a post-reaction strength (CSR) of 63-68%, specifically 63%, 63.5%, 64%, 64.5%, 65%, 65.5%, 66%, 66.5%, 67%, 67.5% or 68%.

[0042] In the method provided by the present invention, blast furnaces with different effective volumes have different requirements for coke quality. The strength of coke after reaction is used as an indicator to characterize the coke quality, and the specific requirements are shown in Table 1.

[0043] Table 1 Coke strength after reaction (CSR) corresponding to different effective volumes of blast furnace

[0044] <![CDATA[Furnace volume / m 3 > Coke CSR / % 1000～1500 63～64 ＞1500～2200 ＞64～66 ＞2200～2500 ＞66～68

[0045] In the method provided by the present invention, the blast furnace throat is divided into 10 gears from the annular area, starting from the center origin of the throat, from the 1st to the 10th gear from the inside to the outside, and the charging system is as follows:

[0046] The ore of the blast furnace falls within the area of ​​the 4th to 8th gears, the innermost gear is the 4th or 5th gear, the ore mass of the innermost gear does not exceed 10-15% of the total ore mass, the ore mass of the 8th gear is 20-35% of the total ore mass, and the ore mass of the remaining gears decreases from the outside to the inside in an arithmetic progression;

[0047] The coke is placed in the area of ​​the 2nd to 9th gears, the coke mass of the 2nd gear is 20-35% of the total coke mass, the coke mass of the 9th gear is 20-30% of the total coke mass, and no coke is placed in the 3rd gear; if there is ore in the 4th gear, the coke mass of the 4th to 8th gears is evenly distributed among the gears; if there is no ore in the 4th gear, no coke is placed in the 3rd to 4th gears, and the coke mass of the 5th to 8th gears is evenly distributed among the gears;

[0048] The material line of blast furnace ore and coke in the blast furnace is the same, and the material line is 1.5-2.5m, specifically 1.5m, 1.6m, 1.7m, 1.8m, 1.9m, 2m, 2.1m, 2.2m, 2.3m, 2.4m or 2.5m.

[0049] In the method provided by the present invention, the oxygen enrichment rate of the blast furnace smelting is 4.5-5.5%, specifically 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5%, 5.1%, 5.2%, 5.3%, 5.4% or 5.5%; the ratio of blast kinetic energy to furnace diameter (E / D) of the blast furnace smelting is 18-19 kJ / (s·m 2 ), specifically 18 kJ / (s·m 2 )、18.1kJ / (s·m 2 )、18.2kJ / (s·m 2 )、18.25kJ / (s·m 2 )、18.3kJ / (s·m 2 )、18.4kJ / (s·m 2 )、18.5kJ / (s·m 2 )、18.6kJ / (s·m 2 )、18.7kJ / (s·m 2 )、18.75kJ / (s·m 2 )、18.8kJ / (s·m 2 )、18.9kJ / (s·m 2 ) or 19 kJ / (s·m 2 ).

[0050] In the method provided by the present invention, the blast kinetic energy is preferably calculated according to formula (1):

[0051]

[0052] In formula (1): Q b The blast volume displayed on the blast furnace instrument, including air and oxygen-rich air with high oxygen content, in m 3 / s;Q O is the oxygen enrichment, unit: m 3 / s;O bis the oxygen (O2) content of oxygen-enriched gas. For example, if the oxygen content is 99%, the value is 0.99 during calculation; s is the air inlet surface of the blast furnace, in m 2 ;p a and p b They are standard atmospheric pressure and actual blast furnace wind pressure, respectively. Their values ​​are 101.325 kPa and the sum of the pressure displayed by the blast furnace instrument and standard atmospheric pressure. If the pressure displayed by the instrument is 350 kPa, then p b 451.325 kPa; T a and T b The absolute temperature corresponding to 0℃ and hot air temperature (℃) is 273.15K. If the hot air temperature is 1200℃, the corresponding absolute temperature is 1473.15K. b ) and oxygen enrichment (Q O ) is often expressed as m 3 / min and m 3 / h, and when calculating, divide by 60 and 360 respectively to convert the unit to m / s.

[0053] In the method provided by the present invention, the ratio of blast kinetic energy to furnace diameter is used as a comprehensive indicator to characterize the air supply system required for the active furnace of blast furnaces of different volumes. Under the condition that the oxygen enrichment rate is 4.5-5.5%, the air volume, air temperature, oxygen enrichment rate, air inlet area, etc. in the air supply system must meet the requirements of Table 2.

[0054] Table 2 Kinetic energy of blast corresponding to different TiO2 contents in slag

[0055] <![CDATA[TiO2 content of slag / %]]> <![CDATA[Blowing kinetic energy to hearth diameter ratio (E / D) / (kJ / (s·m 2 ))]]> Oxygen enrichment rate / % 23～23.5 18～18.25 4.5～5.5 ＞23.5～24 ＞18.25～18.5 4.5～5.5 ＞24.0～24.5 ＞18.5～18.75 4.5～5.5 ＞24.5～25.0 ＞18.75～19.0 4.5～5.5

[0056] In the method provided by the present invention, the coke ratio of the blast furnace smelting is preferably 380-400kg / t, specifically 380kg / t, 381kg / t, 382kg / t, 383kg / t, 384kg / t, 385kg / t, 386kg / t, 387kg / t, 388kg / t, 389kg / t, 390kg / t, 391kg / t, 392kg / t, 393kg / t, 394kg / t, 395kg / t, 396kg / t, 397kg / t the coal ratio for blast furnace smelting is preferably 125-140kg / t, specifically 125kg / t, 126kg / t, 127kg / t, 128kg / t, 129kg / t, 130kg / t, 131kg / t, 132kg / t, 133kg / t, 134kg / t, 135kg / t, 136kg / t, 137kg / t, 138kg / t, 139kg / t or 140kg / t.

[0057] In the method provided by the present invention, the slag-to-iron ratio of the blast furnace smelting is preferably 500-550 kg / t, specifically 500 kg / t, 505 kg / t, 510 kg / t, 515 kg / t, 520 kg / t, 525 kg / t, 530 kg / t, 535 kg / t, 540 kg / t, 545 kg / t or 550 kg / t.

[0058] In the method provided by the present invention, after testing the molten iron and slag obtained from blast furnace smelting, it was found that as the TiO2 content in the slag increased, the Ti content in the molten iron representing the chemical temperature of the molten iron and the molten iron temperature representing the physical temperature both decreased, and the total amounts of C, V, Ti, Si, Mn, P, and S in the molten iron decreased. The specific values ​​are shown in Table 3.

[0059] Table 3 Different slag TiO2 content corresponding to molten iron composition and molten iron temperature

[0060]

[0061] The method provided by the present invention can guide the blast furnace intensified smelting under the high vanadium-titanium pellet ratio, achieve low pig iron cost and reduce carbon emissions in sintering and ironmaking processes, and has huge economic and social benefits.

[0062] For the sake of clarity, the following examples are used to explain in detail. In the following examples of the present invention, unless otherwise specified, percentages % refer to mass percentages, and basicity refers to binary basicity (R2, w(CaO) / w(SiO2)).

[0063] Example 1

[0064] 1750m 3 Blast furnace, furnace diameter 9.5m, furnace throat diameter 6.9m. Vanadium-titanium pellets are produced with 98% vanadium-titanium concentrate + 2% bentonite. The chemical composition of vanadium-titanium concentrate, vanadium-titanium pellets and sintered ore produced with different common ores, as well as the unit consumption of sintered ore and pellets are shown in Table 4. It can be seen that the proportion of vanadium-titanium concentrate in the iron-containing raw materials in the pelletizing process is 100%, and a certain proportion of bentonite is added to obtain pellets, and the basicity of the pellets is 0.20. Vanadium-titanium concentrate is not used in the sintering process, and the basicity of the obtained sintered ore is 2.398. The blast furnace obtains 1t of pig iron, consumes 1245kg of pellets and 570.053kg of sintered ore, and does not use natural lump ore. The proportion of pellets is 68.59% and the proportion of sintered ore is 31.41%.

[0065] Table 4 1750m 3 Chemical composition and unit consumption of raw materials for blast furnaces

[0066]

[0067] During the production process, the blast furnace air volume, oxygen enrichment rate and other air supply parameters are shown in Table 5. Using the air supply system in Table 5, the blast kinetic energy is calculated according to formula (1) to be 171 kJ / s, and the ratio of blast kinetic energy to furnace diameter is 18.04.

[0068] Table 5 1750m 3 Blast furnace air supply parameters

[0069]

[0070] Blast furnace ore batch weight 42 tons / batch, coke batch weight 9-9.2 tons / batch, material line 2.0m, material matrix In the distribution matrix, "0" represents ore, "C" represents coke, and the throat area is divided into 10 levels. The upper row of numbers represents the number of levels from the inside to the outside, and the lower row of numbers represents the number of rings of the charge corresponding to the number of levels.

[0071] Using the above charging system, the mass of the 8th gear ore accounts for 26.67% of the total mass of the ore, the 4th gear accounts for 13.33%, the 7th, 6th and 5th gears account for 26.67%, 20.0% and 13.33% respectively; the 9th gear coke accounts for 25% of the total mass of coke, the 2nd gear accounts for 25%, and the 8th to 4th gears are 10% each.

[0072] Under the condition of coke CSR of 65.74%, as shown in Table 6, the blast furnace coke ratio is 390kg / t, coal ratio (coal injection ratio) is 130kg / t, the furnace grade is 52.68%, and the slag iron ratio is 515kg / t. The obtained molten iron and slag components are shown in Table 7. As can be seen from Table 7, under the above conditions, the slag TiO2 content is 23.50%, the basicity is 1.02, the molten iron Ti content is 0.152%, the total molten iron components (C, V, Ti, Si, Mn, P, S) is 5.306%, and the temperature is 1458°C.

[0073] Table 6 1750m 3 Coke ratio, coal injection ratio and slag-iron ratio of blast furnace

[0074]

[0075] Table 7 1750m 3 Composition of slag and pig iron in blast furnaces

[0076]

[0077] Example 2

[0078] 1350m 3Blast furnace, furnace diameter 8.55m, furnace throat diameter 6.0m. Vanadium titanium pellets are produced with 96% vanadium titanium concentrate + 2% slaked lime + 2% bentonite. The chemical composition of vanadium titanium concentrate, vanadium titanium pellets, sintered ore produced with different common ores, and the unit consumption of sintered ore and pellets are shown in Table 8. It can be seen that after adding 2% slaked lime in the production process of vanadium titanium pellets, the basicity increases from 0.35 of vanadium titanium concentrate to 0.70. The sintering process does not use vanadium titanium concentrate, but some common ores contain a small amount of TiO2. The basicity of the obtained sintered ore is 2.228 and the TiO2 content is 0.19%. The blast furnace obtains 1t of pig iron, consumes 1120kg of pellets and 713.423kg of sintered ore, does not use natural lump ore, and the proportion of pellets is 61.09% and the proportion of sintered ore is 38.91%.

[0079] Table 8 1350m 3 Chemical composition and unit consumption of blast furnace raw materials

[0080]

[0081] During the production process, the blast furnace air volume, oxygen enrichment rate and other air supply parameters are shown in Table 9. Using the air supply system in Table 9, the blast kinetic energy is calculated according to formula (1) to be 160 kJ / s, and the ratio of blast kinetic energy to furnace diameter (E / D) is 18.66.

[0082] Table 9 1350m 3 High air supply parameters

[0083]

[0084] The blast furnace ore batch weight is 36 tons / batch, the coke batch weight is 7.742-7.759 tons / batch, the material line is 1.90m, and the material distribution matrix is

[0085] Using the above charging system, the mass of the 8th gear ore accounts for 31.25% of the total ore mass, the 5th gear accounts for 12.5%, the 7th and 6th gears account for 31.25% and 25.0% respectively; the 9th gear coke accounts for 25% of the total coke mass, the 2nd gear accounts for 25%, and the 8th to 5th gears account for 12.50% respectively.

[0086] Under the condition of coke CSR of 63.82%, as shown in Table 10, the blast furnace coke ratio is 395kg / t, coal ratio is 135kg / t, charging grade is 52.16%, and slag iron ratio is 534kg / t. The obtained molten iron and slag components are shown in Table 11. As can be seen from Table 11, under the above conditions, the slag TiO2 content is 24.20%, the basicity is 1.06, the molten iron Ti content is 0.130%, the total molten iron components (C, V, Ti, Si, Mn, P, S) are 5.187%, and the temperature is 1452°C.

[0087] Table 10 1350m 3 Coke ratio, coal injection ratio and slag-iron ratio of blast furnace

[0088]

[0089] Table 11 1350m 3 Composition of slag and pig iron in blast furnaces

[0090]

[0091] Example 3

[0092] 2000m 3 Blast furnace, furnace diameter 10m, throat diameter 7.6m. Vanadium-titanium pellets are produced with 94% vanadium-titanium concentrate + 2.5% ordinary concentrate + 1.5% slaked lime + 2% bentonite. The chemical composition of vanadium-titanium concentrate, vanadium-titanium pellets and sintered ore produced with different ordinary ores and the unit consumption of sintered ore and pellets are shown in Table 12. It can be seen that the sintering process does not use vanadium-titanium concentrate, and the basicity of the obtained sintered ore is 2.398. The blast furnace consumes 1245kg of pellets and 570.053kg of sintered ore to obtain 1t of pig iron. Natural lump ore is not used. The proportion of pellets is 68.59% and the proportion of sintered ore is 31.41%.

[0093] Table 12 2000m 3 Chemical composition and unit consumption of blast furnace raw materials

[0094]

[0095] During the production process, the blast furnace air volume, oxygen enrichment rate and other air supply parameters are shown in Table 13. Using the air supply system in Table 13, the blast kinetic energy is calculated according to formula (1) to be 189 kJ / s, and the ratio of blast kinetic energy to furnace diameter (E / D) is 18.88.

[0096] Table 13 2000m 3 Blast furnace air supply parameters

[0097]

[0098] The batch weight of blast furnace ore is 47,800 tons / batch, the batch weight of coke is 9.968-10.080 tons / batch, and the material line is 2.1m.

[0099] The cloth matrix is

[0100] Using the above charging system, the mass of the 8th gear ore accounts for 22.22% of the total mass of the ore, the 4th gear accounts for 11.11%, the 7th, 6th and 5th gears account for 27.78%, 22.22% and 16.67% respectively; the 9th gear coke accounts for 22.5% of the total mass of coke, the 2nd gear accounts for 27.5%, and the 8th to 4th gears are 10% each.

[0101] Under the condition of coke CSR of 67.684%, as shown in Table 14, the blast furnace coke ratio is 385kg / t, coal ratio is 135kg / t, charging grade is 52.00%, and slag iron ratio is 534kg / t. The obtained molten iron and slag components are shown in Table 15. As can be seen from Table 15, under the above conditions, the slag TiO2 content is 24.80%, the basicity is 1.04, the molten iron Ti content is 0.115%, the total molten iron components (C, V, Ti, Si, Mn, P, S) is 5.306%, and the temperature is 1450°C.

[0102] Table 14 2000m 3 Coke ratio, coal injection ratio and slag-iron ratio of blast furnace

[0103]

[0104] Table 15 2000m 3 Composition of slag and pig iron in blast furnaces

[0105]

[0106] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A blast furnace smelting method for high-proportion vanadium-titanium pellets, It is characterized in that The process includes: Blast furnace ore and coke fall into the blast furnace throat through the blast furnace's distribution device, and smelting is carried out in the blast furnace to obtain molten iron and slag; The effective volume of the blast furnace is 1000-2500m 3 ; The blast furnace ore includes vanadium-titanium pellets and sintered ore, the binary basicity of the vanadium-titanium pellets is ≤0.8, the binary basicity of the sintered ore is 2-2.4, and the content of the vanadium-titanium pellets in the blast furnace ore is ≥60wt%; The post-reaction strength of the coke is 63-68%; The blast furnace throat is divided into 10 gears from the annular area, starting from the center of the throat and going outwards, from the 1st to the 10th gear; The blast furnace ore falls within the region of the 4th to 8th gears, the innermost gear is the 4th or 5th gear, the ore mass of the innermost gear does not exceed 10-15% of the total ore mass, the ore mass of the 8th gear is 20-35% of the total ore mass, and the ore mass of the remaining gears decreases from the outside to the inside according to an arithmetic progression; The coke is placed in the area of ​​the 2nd to 9th gears, the coke mass of the 2nd gear is 20-35% of the total coke mass, the coke mass of the 9th gear is 20-30% of the total coke mass, and no coke is placed in the 3rd gear; if there is ore in the 4th gear, the coke mass of the 4th to 8th gears is evenly distributed among the gears; if there is no ore in the 4th gear, no coke is placed in the 3rd to 4th gears, and the coke mass of the 5th to 8th gears is evenly distributed among the gears; The blast furnace ore and coke have the same feed line in the blast furnace, and the feed line is 1.5 to 2.5 m; The oxygen enrichment rate of the blast furnace smelting is 4.5-5.5%, and the ratio of blast kinetic energy to furnace diameter is 18-19 kJ / (s·m 2 ).

2. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The kinetic energy of the blast is calculated according to formula (1): In formula (1): Q b The blast volume displayed on the blast furnace instrument, including air and oxygen-rich volume with high oxygen content, in m 3 / s;Q O is the oxygen enrichment, unit: m 3 / s;O b is the oxygen content in oxygen-enriched air; s is the air inlet surface of the blast furnace, unit: m 2 ; p a and p b are standard atmospheric pressure and actual blast furnace wind pressure, in kPa; T a and T b The absolute temperatures corresponding to 0°C and hot air temperature, in K.

3. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that If the expected TiO 2 The content is 23-23.5wt%, and the ratio of the blast kinetic energy to the furnace diameter is controlled at 18-18.25 kJ / (s·m 2 ); If the expected TiO 2 The content is greater than 23.5% and less than 24wt%, and the ratio of the blast kinetic energy to the furnace diameter is controlled to be greater than 18.25kJ / (s·m 2 ) and ≤18.5kJ / (s·m 2 ); If the expected TiO 2 The content is greater than 24wt% and less than 24.5wt%, and the ratio of the blast kinetic energy to the furnace diameter is controlled to be greater than 18.5kJ / (s·m 2 ) and ≤18.75kJ / (s·m 2 ); If the expected TiO 2 The content is greater than 24.5wt% and less than 25wt%, and the ratio of the blast kinetic energy to the furnace diameter is controlled to be greater than 18.75kJ / (s·m 2 ) and ≤19kJ / (s·m 2 ).

4. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that If the effective volume of the blast furnace is 1000-1500m 3 , then use coke with a strength of 63-64% after reaction; If the effective volume of the blast furnace is > 1500m 3 and ≤2200m 3 , then use coke with a strength after reaction of >64% and ≤66%; If the effective volume of the blast furnace is > 2200m 3 and ≤2500m 3 , then use coke with a post-reaction strength of >66% and ≤68%.

5. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The TiO 2 The content is 9-12wt%, V 2 O 5 The content is 0.4~0.8wt%.

6. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The content of vanadium-titanium magnetite concentrate in the raw material for preparing the vanadium-titanium pellets is ≥90wt%.

7. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 6, It is characterized in that The raw materials for preparing the vanadium-titanium pellets also include one or more of ordinary iron ore concentrate, slaked lime and bentonite.

8. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The TiO 2 Content ≤1wt%,V 2 O 5 Content ≤0.05wt%.

9. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The ore entering the blast furnace has a grade of 50-55%.

10. The blast furnace smelting method of high-proportion vanadium-titanium pellets according to claim 1, It is characterized in that The coke ratio of the blast furnace smelting is 380-400 kg / t; the coal ratio of the blast furnace smelting is 125-140 kg / t.

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