Iron ore blending method for blast furnace smelting of high-titanium schreyerite

Abstract

The invention belongs to the field of blast furnace ironmaking, and particularly relates to an iron ore blending method for blast furnace smelting of high-titanium schreyerite, which comprises the following processes: (1) establishing an ore blending model for blast furnace smelting of high-titanium schreyerite; (2) determining the chemical components of the sintered ore and the fuel consumption in the sintering process; (3) calculating the schreyerite proportion; (4) calculating the charging grade; and (5) calculating the pig iron cost. The method not only can stably control the slag components and the slag-iron ratio, but also can obtain the cost of ton iron, thereby providing reference for reasonable ore blending of enterprises.

Description

Technical Field

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

[0002] Reasonable ore blending is the basis for obtaining suitable slag composition, furnace grade (or slag-iron ratio) and pig iron cost in blast furnace smelting. Reasonable ore blending can not only obtain suitable slag composition, but also provide valuable guidance for reducing pig iron cost. When blast furnace smelting ordinary ore, the evaluation of iron ore is mainly to examine the influence of a certain iron ore on the slag-iron ratio and pig iron cost on the premise of meeting the slag basicity requirements. If this kind of iron ore is used, not only the amount of slag produced per unit of pig iron is small and the requirements of the slag for chemical composition are met, but also the raw material cost and fuel cost per unit of pig iron are reduced, then this iron ore has a high cost performance. However, when the blast furnace is smelting high-titanium vanadium titanium, the requirements for iron ore are more complicated.

[0003] When blast furnace smelting high-titanium vanadium-titanium ore, the ore blending is different from that of smelting ordinary ore or low-titanium ore. The ore blending of high-titanium vanadium-titanium ore in blast furnace smelting must not only meet the requirements of slag chemical composition, especially alkalinity, but also consider the influence of the amount of slag-making components brought in by iron ore, such as CaO, SiO2, MgO, Al2O3, etc. on the TiO2 content of slag or the V content of molten iron. If these slag-making components brought in by iron ore are not enough to make the total amount of slag reach a certain value, thereby reducing the TiO2 content in the slag to a certain value, the difficulty of blast furnace smelting will be significantly increased, and even smelting will be impossible. For example, in addition to vanadium-titanium magnetite, the amount of other iron ores that do not contain TiO2 or have a low TiO2 content is too small, so that the TiO2 content in the slag reaches 25% or even higher. In the process of blast furnace smelting, foamy slag, sticky slag, and a large amount of metallic iron in the slag are very likely to occur. At this time, it is necessary to increase the amount of other iron ores without TiO2 or with low TiO2 or use iron ores with low iron grade (TFe content), increase the amount of CaO, SiO2, MgO, and Al2O3 in the slag, and reduce the TiO2 content in the slag to an appropriate content, such as 20%-23%. Secondly, by adding flux (limestone or quicklime with high CaO content, etc.), the binary basicity of the slag (the mass fraction ratio of CaO and SiO2) is maintained at an appropriate level to prevent the melting temperature of the slag (usually refers to the temperature at which the viscosity of the slag increases sharply during the temperature reduction process or the viscosity increases to a temperature that is not suitable for smelting, such as 2Pa·s) from being too high, and the slag has a certain desulfurization ability. The amount of flux added is also affected by the chemical composition of the iron ore and the ore blending, and further affects the ore blending cost per ton of iron. Third, although other slag components, such as MgO and Al2O3, also need to be kept within an appropriate range, they are usually not the main factors affecting the performance of the slag. When blending the ore, it is only necessary to prevent them from being too low or too high. Fourth, after meeting these requirements, it is also hoped that the price of iron ore is low. After using these iron ores, it is not only necessary to meet the above requirements for the slag making system, but also to reduce the slag amount per ton of iron as much as possible while minimizing the cost of blending ore per ton of iron, that is, the slag-iron ratio, so as to reduce the consumption of coke or pulverized coal during blast furnace smelting, thereby reducing the fuel cost per ton of iron. Therefore, when blast furnace smelting vanadium high-titanium vanadium-titanium ore, the evaluation of the cost performance of iron ore is much more complicated than smelting ordinary ore. Establishing an iron ore blending method for blast furnace smelting of vanadium-titanium ore is conducive to obtaining a lower cost blending result under complex and changing conditions.

[0004] The commonly used ore blending method is usually to adjust the slag composition or slag-iron ratio by adjusting the amount of flux or iron ore in the sintering process after determining the amount or ratio of pellets, lump ore, coke ratio (coke per ton of iron consumption) or coal injection ratio (coal powder injection per ton of iron consumption) in the blast furnace process. For the smelting of high-titanium vanadium-titanium ore, when this method is used to blend the ore, it is often the case that the slag TiO2 content or slag binary basicity, furnace grade or ore blending cost do not meet expectations. At this time, it is necessary to repeatedly adjust the amount of flux and iron ore in the sintering process to meet the above requirements. In this way, not only the complexity and workload of ore blending are increased, but also the accuracy of ore blending results is poor, and key parameters such as slag composition, such as binary basicity, TiO2 content, and slag-iron ratio will fluctuate within a certain range, and in actual production, the fluctuation range may be further expanded, which has an adverse effect on blast furnace smelting. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide an iron ore blending method for blast furnace smelting of high-titanium vanadium-titanium ore, which method can not only stably control the slag composition and slag-iron ratio, but also obtain the cost per ton of iron at the same time, thereby providing a reference for enterprises to reasonably blend ore.

[0006] The present invention provides an iron ore blending method for smelting high-titanium vanadium-titanium ore in a blast furnace, comprising the following steps:

[0007] (1) Establishment of ore blending model for blast furnace smelting of high-titanium vanadium-titanium ore:

[0008] (1.1) Iron balance:

[0009] From the Fe element balance we can get:

[0010] ∑[x i ×w(Fe) i ]+∑[x f ×w(Fe) f ]+∑[x j ×w(Fe) j ]=1000×w(Fe)+μ·w(Fe) z +x c w(Fe) c (1);

[0011] In formula (1): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, unit: kg / t; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, usually including coke and pulverized coal injection, unit: kg / t; ③x j4μ is the amount of other iron ores (such as vanadium-titanium pellets, acid-fired sintered ore, lump ore, iron-manganese ore, fluorite, etc., the same below) consumed in the blast furnace process corresponding to a ton of iron, in kg / t; 5x is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; C The amount of dust produced by the blast furnace process per ton of iron, in kg / t; if the value is 1500kg / t, then the value is 1500; ⑥w(Fe) i 、w(Fe) f 、w(Fe) j 、w(Fe) Z 、w(Fe) C is the Fe content of different iron ores, fuels in the sintering process, other iron ores, slag and dust in the blast furnace process. If its value is 56%, the value is 0.56;

[0012] From formula (1), we can get:

[0013] ∑(x i w(Fe) i )=1000×w(Fe)+x z w(Fe) z +x c w(Fe) c -∑[x f w(Fe) f ]-∑[x j w(Fe) j ] (2);

[0014] In formula (2), let:

[0015] w(Fe) i =k 1i (3);

[0016] 1000×w(Fe)+x z w(Fe) z +x c w(Fe) c -∑[x f w(Fe) f ]-∑[x j w(Fe) j ] = λ1 (4);

[0017] We can get:

[0018] ∑(k 1i × i )=λ1 (5);

[0019] (1.2) Slag balance:

[0020] From the mass balance of slag-forming components in the slag, we can get:

[0021]

[0022] In formula (6): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, in kg / t. If the value is 1500kg / t, then the value is 1500; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j is the amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④μ is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; ⑤x C The amount of dust generated by the blast furnace process corresponding to a ton of iron, unit: kg / t; ⑥δ i , δ f , δ c , δ j are the sum of the mass contents of CaO, SiO2, MgO, Al2O3 and TiO2 in different iron ores, fuel, furnace dust and other iron ores in the blast furnace process. If the value is 20%, the value is 0.2; ⑦ [Si] and [Ti] are the mass contents of Si and Ti in molten iron respectively. If the value is 0.20%, the value is 0.002; ⑧ξ is the sum of the mass contents of CaO, SiO2, MgO, Al2O3 and TiO2 in slag. If the value is 96.5%, the value is 0.965; ⑨μ is the slag-iron ratio, unit kg / t. If the value is 560kg / t, the value is 560;

[0023] From formula (6), we can get:

[0024]

[0025] In formula (7), let:

[0026] δ i =k 2i (8);

[0027]

[0028] We can get:

[0029] ∑(k 2i × i ) = λ2 (10);

[0030] (1.3) Slag binary basicity R2 balance:

[0031] From the binary alkalinity R2 balance, we can get:

[0032]

[0033] After sorting, we can get:

[0034]

[0035] In formula (12): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, in kg / t. If the value is 1500kg / t, then the value is 1500; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j The amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④x C The amount of dust produced by the blast furnace process per ton of iron, in kg / t; ⑤w(CaO) i 、w(CaO) f 、w(CaO) j 、w(CaO) C are the CaO mass contents in different iron ores, fuels, other iron ores and furnace dust in the sintering process; ⑥w(SiO2) i 、w(SiO2) f 、w(SiO2) j 、w(SiO2) C are the mass content of SiO2 in different iron ores, fuels, other iron ores in blast furnace processes and furnace dust; ⑦[Si] is the mass content of Si in molten iron. If its value is 0.18%, the value is 0.0018; ⑧R2 is the binary basicity of slag;

[0036] In formula (12):

[0037] w(CaO) i -R2·w(SiO2) i =k 3i (13);

[0038]

[0039] We can get:

[0040] ∑(k 3i × i )=λ3 (15);

[0041] (1.4) TiO2 balance

[0042] From the TiO2 balance, we can get:

[0043]

[0044] In formula (16): ①x iThe amount of different iron ores consumed in the sintering process corresponding to a ton of iron, in kg / t. If the value is 1500kg / t, then the value is 1500; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j is the amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④μ is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; ⑤x C The amount of dust produced by the blast furnace process per ton of iron, in kg / t; ⑥w(TiO2) i 、w(TiO2) f 、w(TiO2) c 、w(TiO2) j 、w(TiO2) μ ⑦ [Ti] is the Ti content of different iron ores, fuels, furnace dust, other iron ores and slag in the blast furnace process. If its value is 10%, the value is 0.1; ⑦ [Ti] is the Ti content of molten iron. If its value is 0.20%, the value is 0.002;

[0045] By rearranging formula (16), we can get:

[0046]

[0047] In formula (17), let:

[0048] w(TiO2) i =k 4i w(TiO2) i =k 4i (18);

[0049]

[0050] We can get:

[0051] ∑(k 4i × i ) = λ4 (20);

[0052] (1.5) Iron ore consumption:

[0053] From equations (5), (10), (15), and (20), we can obtain the following linear equations:

[0054]

[0055] By solving the linear equation group (21), the dosage of different iron ores in the sintering process per ton of iron is obtained; according to the calculation result of formula (21), the chemical composition and dosage of the sintered ore are obtained through the calculation model of the chemical composition of the sintered ore; on the one hand, through the chemical composition of the sintered ore, it is possible to preliminarily judge whether the batching structure is reasonable, for example, whether the basicity of the sintered ore is too high or too low, and whether the grade entering the furnace is too low; on the other hand, according to the calculated chemical composition and dosage of the sintered ore, combined with the known dosage of blast furnace acid burning and blast furnace pellets, the grade entering the furnace under this condition can be calculated;

[0056] (2) Determination of the chemical composition of sintered ore and the amount of fuel used in the sintering process:

[0057] (2.1) Determination of the chemical composition of sintered ore. The chemical composition of sintered ore produced by the sintering process is calculated by the following formula:

[0058] Y i =x i ·(1-Ig xi -S xi ·D Sxi ) (twenty two);

[0059]

[0060]

[0061] In formulas (22) to (24), Yi is the burnout of a certain raw material or fuel in the sintering process, in kg / kg (dry basis ore); x i The amount of a certain raw material or fuel used in the sintering process per ton of pig iron, in kg / t. For example, if the amount of a certain raw material used per ton of pig iron is 200 kg, the value is 200 during calculation. xi is the burnout value of a certain raw material or fuel in the sintering process. If its value is 1%, the value is taken as 0.01 during calculation; S xi is the sulfur content of a certain raw material or fuel in the sintering process. If its value is 0.5%, the value is taken as 0.05 during calculation; D Sxi is the desulfurization rate of a certain raw material or fuel in the sintering process. If its value is 95%, the value is 0.95 in the calculation; Cxi is the mass content of a certain component (such as CaO) in a certain raw material or fuel in the sintering process. If its value is 10%, the value is 0.1 in the calculation; C i It is the mass percentage of a certain component (such as CaO) in the sintered ore. If the calculated result is 10%, it is expressed as 10%; S i is the sulfur mass percentage of the sintered ore;

[0062] (2.2) Determination of fuel consumption in sintering process:

[0063] Usually, the proportion of fuel used in the sintering process can be studied in advance, such as setting its proportion to 4% of the iron-containing raw materials in the sintering process; however, the amount of fuel powder used in the sintering process will not only affect the quality of the sintered ore, but in this scheme, it will mainly affect the burning amount and chemical composition of the sintered ore, and further affect the amount of iron-containing raw materials used in the blast furnace process; therefore, even if the amount or proportion of a certain raw material or fuel used in the blast furnace process has been set, the amount of raw materials used in the sintering process cannot be determined separately first, and then the amount of fuel used can be determined according to the fuel proportion, because the amounts of these two types of furnace materials affect each other;

[0064] Therefore, the amount of fuel used in the sintering process needs to be set to an initial value first; from this initial value, the chemical composition of the sintered ore and the proportion of pellets under certain conditions are calculated; if the ratio of this initial value to other raw materials in the sintering process does not meet the set value, the amount of fuel is adjusted according to the calculation until the ratio of fuel to raw material reaches the set value;

[0065] (3) Calculation of vanadium-titanium ore ratio:

[0066] The ratio of vanadium-titanium ore is the mass fraction of vanadium-titanium ore in all iron-containing raw materials:

[0067]

[0068] In formula (25), x iV-T The amount of different vanadium-titanium ores used in sintering and blast furnace processes per ton of iron, such as vanadium-titanium concentrate used in the sintering process, blast furnace vanadium-titanium pellets, acidic vanadium-titanium sinter, etc., in kg / t; x i The amount of different types of iron ores used in sintering and blast furnace processes, including vanadium-titanium ore and other iron ores, in kg / t;

[0069] (4) Calculation of furnace grade:

[0070] The charging grade is the ratio of the product of the mass of the iron-containing charge used in the blast furnace and its iron grade to the total mass of the iron-containing charge:

[0071]

[0072] In formula (26), xj is the mass of iron-containing raw materials used in the blast furnace process per ton of iron, including basic sintered ore produced by the sintering process, pelletized ore produced by the pelletizing enterprise, natural lump ore or acid-burned sintered ore, etc., in kg / t; TFej is the iron grade of the above iron-containing raw materials, that is, the TFe content. If its value is 55%, the value is taken as 0.55 during calculation;

[0073] (5) Calculation of pig iron cost. The cost performance of iron ore smelted in a vanadium-titanium blast furnace can be calculated according to formula (27):

[0074] ∑(P p +P m)·x i +P J ·x J +P M ·x M +∑(P j ·x j )=P t (27);

[0075] In formula (27): ①P p and P m are the purchase price and processing cost of iron ore and flux in the sintering process, respectively, in RMB / ton; ②x i The quantity of iron ore and flux consumed in the sintering process corresponding to a ton of iron, in kg / t; ③P J , P M , P j are the prices of coke, PCI and other iron ore in blast furnace process, in Yuan / ton; ④x J The amount of coke consumed per unit of pig iron, in kg / t; ⑤x M The amount of PCI coal consumed per unit of pig iron, in kg / t; ⑥x j The amount of iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ⑦P t Total cost of raw fuel per ton of iron, unit: RMB / ton;

[0076] According to formula (27), the total material consumption (iron ore and fuel) cost per ton of iron under different iron ore ratio conditions can be obtained, where Σ(P p +P m )·x i It can be understood as the cost of ore distribution. t When the value is the smallest, it is the optimal ore ratio; by comparing the pig iron costs under different conditions, we can get the ore ratio structure when the cost is lower, which can provide guidance for enterprises in low-cost production.

[0077] Preferably, the iron ore blending method further comprises: calculating the proportion of vanadium-titanium ore and blending cost under different conditions according to the amount of iron ore used in the sintering process, the amount and price of blast furnace acid burning, blast furnace pellets, coke, and pulverized coal injection.

[0078] Preferably, the iron ore blending method further comprises: when calculating the vanadium-titanium ore ratio and blending cost under the different conditions, among the three factors of slag-iron ratio μ, slag TiO2 content, and slag binary basicity R2, first fixing the other two factors, and only investigating the influence of the change of one of the factors; for example, when investigating the influence of slag binary basicity R2, the slag-iron ratio μ and slag TiO2 content may be fixed first, and the influence of R2 on the furnace grade etc. may be obtained by adjusting the value of slag binary basicity R2; correspondingly, in this case, if the slag-iron ratio or slag TiO2 content is changed, the influence of slag binary basicity R2 on the furnace grade etc. may be obtained at another slag-iron ratio or slag TiO2 content level;

[0079] Secondly, when a certain iron ore shows a negative value, it means that the values ​​of the three factors, namely, the slag-iron ratio μ, the slag TiO2 content, and the slag binary basicity R2, are set unreasonably, and the iron ore under the above given conditions cannot obtain the required results of the slag-iron ratio μ, the slag TiO2 content, and the slag binary basicity R2.

[0080] Compared with the prior art, the present invention provides an iron ore blending method for blast furnace smelting of high-titanium vanadium-titanium ore. The method comprehensively considers the particularity of the smelting of high-titanium vanadium-titanium ore, and establishes a high-titanium vanadium-titanium ore blending model based on the reasonable ore blending under the condition of low-cost smelting. It can not only stably control the slag composition and slag-to-iron ratio, but also obtain the cost per ton of iron at the same time, which is of great reference significance for guiding enterprises to reasonably blend ore. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0082] Figure 1 This is a graph showing the change in pig iron cost and sintered ore cost when comparing the performance-price ratios of ores of different prices provided in Example 1 of the present invention;

[0083] Figure 2 is a graph showing the change in pig iron cost and sintered ore cost at different slag-iron ratios provided in Example 2 of the present invention;

[0084] Figure 3 This is a graph showing the changes in pig iron cost and sintered ore cost at different slag-iron ratios under a fixed amount of vanadium-titanium ore 2 provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0085] 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.

[0086] Example 1

[0087] The chemical composition of the raw materials is shown in Table 1.

[0088] Table 1 Chemical composition and unit price of raw materials and fuels

[0089] name TFe CaO <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[V2O5]]> P S Burning unit price Processing cost Limestone powder 0.01 53.39 0.83 1.43 0.18 0 0 0.010 0.01 41.00 90.00 150 Active ash 0.01 89.52 0.57 4.2 0.39 0 0 0.010 0.016 6.50 550.00 150 Vanadium titanium concentrate 1 57.14 0.5 2.61 2.92 3.37 10.24 0.71 0.002 0.339 -1.50 520.00 150 Vanadium Titanium Concentrate 2 55.04 1.03 2.97 2.53 3.38 12.04 0.59 0.002 0.792 -1.50 470.00 150 Ordinary Mine 1 62.57 0.5 7.32 0.5 1.5 0 0 0.026 0.1 2.00 1300.00 150 Ordinary Mine 2 58.84 1.87 6.08 6.07 0.44 0 0 0.024 0.27 2.00 750.00 150 Ordinary Mine 3 55.98 4.08 5.65 2.02 2.61 1.26 0 0.074 0.637 2.00 580.00 150 Ordinary Mine 4 51.3 5.21 11.35 2.59 2 0.08 0 0.074 0.84 -1.00 500.00 150 Sintered coke powder 0 0.56 7.4 0.15 4.06 0 0 0 0.14 70.00 1400.00 150 Coke 0.589 0.642 7.03 0.141 3.24 0 0 0.001 0.69 2850.00 0 Pulverized Coal Injection 0.52 0.592 6.2 0.155 3.485 0 0 0.001 0.75 1750.00 0 Acid Burn 52.47 5.16 7.23 2.42 3.88 5.66 0.392 0.057 0.032 600.00 0 Pelletized Ore 54.87 0.7 3.53 2.94 3.37 9.74 0.68 0.009 0.009 600.00 0 Furnace dust 40.38 6.5 6.84 2.58 2.87 3.43 0.336 0.020 0.24 90.00

[0090] In order to compare the cost performance of two common ores with relatively high prices and grades, the ore blending structure and pig iron cost under different conditions when only one of the ores is used are compared, and the corresponding conditions are set, as shown in Table 2. During the calculation, the mass ratio of limestone to quicklime is 0.52:0.48, which is converted into a flux; the mass ratio of vanadium-titanium ore 1 and vanadium-titanium ore 2 is 1:9, which is converted into a vanadium-titanium ore; ordinary ore 1 and ordinary ore 2 are converted into an ordinary ore according to the corresponding ratio. In this calculation example, ordinary ore 1: ordinary ore 2 is 1:0, that is, ordinary ore 2 is not used, such as ordinary ore 1: ordinary ore 2 is 0:1, that is, ordinary ore 1 is not used; ordinary ore 3 and ordinary ore 4 are converted into an ordinary ore according to a certain ratio. Then, according to formula (21), the converted flux, the converted vanadium-titanium ore, and the two converted ordinary ores are used as unknowns x i , solve these four unknowns, split the calculated results according to the original conversion ratio, and obtain different sintering material consumption under different conditions.

[0091] When ordinary ore 2 is not used, ordinary ore 3: ordinary ore 4 are 0:1 (P1-1, P2-1), 1:9 (P1-2, P2-2), 2:8 (P1-3, P2-3), 3:7 (P1-4, P2-4), 4:6 (P1-5, P2-5) and 5:5 (P1-6, P2-6), the corresponding sintering material consumption is shown in Table 3. As can be seen from Table 3, P1-1 to P1-6 are the sintering material consumption when the amount of ordinary ore 2 with a relatively high price is 0kg / t, and the amount of other raw materials and fuels is adjusted to achieve the sintering material consumption set in Table 2. P2-1 to P2-6 are the sintering material consumption when the amount of ordinary ore 1 with a relatively high price is 0kg / t, and the amount of other raw materials and fuels is adjusted to achieve the sintering material consumption set in Table 2.

[0092] Table 4 shows the charging grade, blast furnace charge structure, and vanadium-titanium ore ratio under different schemes, Table 5 shows the V composition of blast furnace slag and molten iron under different schemes, Table 6 shows the composition and alkalinity of sintered ore, and Table 7 shows the cost of pig iron under different schemes. It can be seen that when only one of the two ores with the same price of ordinary ore 1 and ordinary ore 2 is used, the ore blending structure that meets the conditions set in Table 2 can be obtained by adjusting the amount of other raw materials and fuels. The chemical composition of sintered ore and slag can also meet the requirements of blast furnace smelting. However, under different ore blending schemes, the ore blending cost and pig iron cost are quite different. From Figure 1 It can be seen more intuitively that when using the more expensive common ore 1, the ore blending cost obtained under different ore blending structures is generally higher than that of the relatively low-priced common ore 2. The slag-iron ratio remains unchanged, the coke ratio, coal ratio and pelletizing ore usage remain unchanged, and the cost of other raw materials and fuels in the blast furnace process remains unchanged. If the usage of these two iron ores is further reduced, the sintering ore blending will be close, but the results obtained by the ore blending structure will not meet the requirements set in Table 2. From the changes in pig iron cost and sintering ore blending cost under different ore blending structures, it can be concluded that common ore 2 is more cost-effective than common ore 1.

[0093] Table 2 Comparison of cost performance of ores at different prices Setting conditions

[0094]

[0095] Table 3 Sintering material consumption (kg / t) when comparing the cost performance of ores at different prices

[0096]

[0097]

[0098] Table 4 Furnace grade, charge structure and vanadium-titanium ore ratio when comparing the cost performance of ores at different prices

[0099]

[0100] Table 5 Slag and molten iron composition (%) when comparing the cost performance of ores at different prices

[0101] Solution No. CaO <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[R2]]> <![CDATA[R3]]> [V] P1-1 25.96 24.72 9.03 13.28 22.50 1.05 1.42 0.303 P1-2 25.90 24.66 9.09 13.34 22.50 1.05 1.42 0.302 P1-3 25.82 24.59 9.17 13.42 22.50 1.05 1.42 0.301 P1-4 25.72 24.50 9.27 13.51 22.50 1.05 1.43 0.300 P1-5 25.59 24.38 9.39 13.63 22.50 1.05 1.44 0.298 P1-6 25.42 24.21 9.56 13.80 22.50 1.05 1.44 0.296 P2-1 24.69 23.51 12.23 12.57 22.50 1.05 1.57 0.303 P2-2 24.73 23.55 12.04 12.67 22.50 1.05 1.56 0.302 P2-3 24.79 23.61 11.80 12.80 22.50 1.05 1.55 0.301 P2-4 24.86 23.68 11.48 12.97 22.50 1.05 1.53 0.300 P2-5 24.97 23.78 11.03 13.22 22.50 1.05 1.51 0.299 P2-6 25.13 23.93 10.35 13.59 22.50 1.05 1.48 0.296

[0102] Table 6 Sinter composition and basicity when comparing the cost performance of ores at different prices

[0103]

[0104]

[0105] Table 7 Pig iron cost when comparing the performance-price ratio of ores at different prices (yuan / ton)

[0106] Solution No. Total Cost Sintering ore blending cost Blast furnace ore cost Total ore allocation cost Blast furnace fuel costs P1-1 2817.696 881.696 540.000 1421.696 1396.000 P1-2 2802.230 866.230 540.000 1406.230 1396.000 P1-3 2782.967 846.967 540.000 1386.967 1396.000 P1-4 2759.039 823.039 540.000 1363.039 1396.000 P1-5 2727.905 791.905 540.000 1331.905 1396.000 P1-6 2686.041 750.041 540.000 1290.041 1396.000 P2-1 2695.534 759.534 540.000 1299.534 1396.000 P2-2 2692.269 756.269 540.000 1296.269 1396.000 P2-3 2688.041 752.041 540.000 1292.041 1396.000 P2-4 2682.459 746.459 540.000 1286.459 1396.000 P2-5 2674.554 738.554 540.000 1278.554 1396.000 P2-6 2662.664 726.664 540.000 1266.664 1396.000

[0107] Example 2

[0108] According to the production experience of the enterprise, taking the slag-iron ratio of 520kg / t as the benchmark, when the furnace grade increases by 1 percentage point, the coke ratio and coal injection ratio will be reduced by 1.5 percentage points respectively. When the slag-iron ratio changes, the blast furnace ore structure and fuel ratio will change accordingly, and the corresponding pig iron cost will change accordingly. The setting conditions for the change of ore structure at different slag-iron ratios are shown in Table 8. When calculating, the mass ratio of limestone and quicklime is 0.52:0.48, which is converted into a flux; the mass ratio of vanadium-titanium ore 1 and vanadium-titanium ore 2 is 1:9, which is converted into a vanadium-titanium ore; ordinary ore 1 and ordinary ore 2 are converted into an ordinary ore according to the corresponding ratio. In this calculation example, ordinary ore 1: ordinary ore 2 is 1:1, which is converted into an ordinary ore; ordinary ore 3: ordinary ore 4 is 0:1, which is converted into an ordinary ore. Then, according to formula (21), the converted flux, the converted vanadium-titanium ore, and the two converted ordinary ores are used as unknown variables x i , solve these four unknowns, split the calculated results according to the original conversion ratio, and obtain different sintering material consumption under different conditions.

[0109] When the slag-iron ratio is determined, the furnace grade at the corresponding slag-iron ratio can be obtained. When the slag-iron ratio changes, the corresponding coke ratio and coal injection ratio are adjusted with the changes in the furnace grade and slag-iron ratio, so that the changes in sintering material consumption at different slag-iron ratios are shown in Table 9, the furnace grade, vanadium-titanium ore ratio, coke ratio, coal injection ratio, etc. are shown in Table 10, the sintered ore composition is shown in Table 11, the slag-iron composition is shown in Table 12, and the pig iron cost changes are shown in Table 13. It can be seen that with the increase of the slag-iron ratio, the furnace grade is reduced from 52.93% to 50.37%, and the reduction in the ore blending cost exceeds the increase in the fuel cost, so the total cost is reduced. Under this condition, reducing the furnace grade is conducive to reducing the pig iron cost.

[0110] Table 8 Calculation conditions for ore structure at different slag-iron ratios

[0111]

[0112] Table 9 Sintering material consumption at different slag-iron ratios (kg / t)

[0113] Solution No. limestone quicklime Sintered coke powder Vanadium Titanite 1 Vanadium Titanite 1 Ordinary Mine 1 Ordinary Mine 2 Ordinary Mine 3 Ordinary Mine 4 G1 74.564 68.828 49.400 21.980 197.822 242.696 242.696 0.000 89.595 G2 75.073 69.299 50.000 23.838 214.546 209.613 209.613 0.000 148.041 G3 75.581 69.768 50.600 25.697 231.269 176.506 176.506 0.000 206.547 G4 76.088 70.235 51.200 27.555 247.992 143.374 143.374 0.000 265.112 G5 76.597 70.705 51.900 29.413 264.716 110.284 110.284 0.000 323.578 G6 77.101 71.170 52.500 31.271 281.438 77.105 77.105 0.000 382.257 G7 77.604 71.635 53.100 33.129 298.160 43.902 43.902 0.000 440.991 G8 78.106 72.098 53.700 34.987 314.881 10.677 10.677 0.000 499.780

[0114] Table 10 Furnace grade, charge structure and vanadium-titanium ore ratio at different slag-iron ratios

[0115]

[0116] Table 11 Composition of slag and molten iron at different slag-iron ratios (%)

[0117] Solution No. CaO <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[R2]]> <![CDATA[R3]]> [V] G1 25.03 23.83 11.16 12.98 22.50 1.05 1.52 0.290 G2 25.16 23.96 10.91 12.98 22.50 1.05 1.51 0.294 G3 25.28 24.08 10.66 12.97 22.50 1.05 1.49 0.298 G4 25.40 24.20 10.43 12.97 22.50 1.05 1.48 0.303 G5 25.52 24.31 10.20 12.97 22.50 1.05 1.47 0.307 G6 25.63 24.41 9.99 12.97 22.50 1.05 1.46 0.312 G7 25.74 24.52 9.78 12.96 22.50 1.05 1.45 0.316 G8 25.85 24.62 9.58 12.96 22.50 1.05 1.44 0.321

[0118] Table 12 Composition and basicity of sintered ore at different slag-iron ratios

[0119]

[0120]

[0121] Table 13 Pig iron cost at different slag-iron ratios (yuan / ton)

[0122] Solution No. Total Cost Sintering ore blending cost Blast furnace ore cost Total ore allocation cost Blast furnace fuel costs G1 2821.008 908.594 540.000 1448.594 1372.415 G2 2802.222 881.835 540.000 1421.835 1380.388 G3 2783.304 855.055 540.000 1395.055 1388.250 G4 2764.254 828.254 540.000 1368.254 1396.000 G5 2745.292 801.645 540.000 1341.645 1403.647 G6 2725.990 774.804 540.000 1314.804 1411.186 G7 2706.565 747.944 540.000 1287.944 1418.621 G8 2687.018 721.065 540.000 1261.065 1425.953

[0123] Example 3

[0124] If the amount of a certain iron ore is fixed, it is necessary to remove it from the unknown parameters of the sintering ingredients, and the amount of other iron ores is taken as the unknown parameter xi. For example, if the amount of vanadium-titanium ore 2 in the sintering process is fixed to 200 kg / t, the corresponding setting conditions are shown in Table 14. At this time, vanadium-titanium ore 1 is used as a variable alone; the mass ratio of limestone and quicklime is 0.52:0.48, which is converted into a flux; ordinary ore 1 and ordinary ore 2 are converted into an ordinary ore at a ratio of 1:1; ordinary ore 3: ordinary ore 4 are converted into an ordinary ore at a ratio of 0:1. Then, according to formula (21), the converted flux, the converted vanadium-titanium ore, and the two converted ordinary ores are used as unknown variables x i , solve these four unknowns, split the calculated results according to the original conversion ratio, and obtain different sintering material consumption under different conditions.

[0125] When the amount of vanadium-titanium ore 2 is fixed at 200kg / t, the changes in material consumption in the sintering process, furnace grade, coke ratio, coal ratio, slag-iron composition, sintering ore composition, pig iron cost, etc. are shown in Tables 15 to 19. It can be seen that when the amount of vanadium-titanium ore 2 is fixed at 200kg / t, the ore blending structure and pig iron cost under different slag-iron ratios or furnace grades can be obtained through this ore blending method. Judging from the ore blending results, as the slag-iron ratio increases and the furnace grade decreases, the pig iron cost decreases, that is, under this condition, the slag-iron ratio is increased and the furnace grade is reduced, the pig iron cost decreases. Figure 3 It can be seen that the reduction in ore blending costs is greater than the increase in fuel costs, so the total cost is reduced.

[0126] Table 14 Calculation and setting conditions of ore structure at different slag-iron ratios with fixed vanadium-titanium ore 2 dosage

[0127]

[0128] Table 15 Sintering material consumption at different slag-iron ratios with fixed vanadium-titanium ore 2 dosage (kg / t)

[0129] Solution No. limestone quicklime Sintered coke powder Vanadium Titanite 1 Vanadium Titanite 1 Ordinary Mine 1 Ordinary Mine 2 Ordinary Mine 3 Ordinary Mine 4 GT-1 74.588 68.850 49.400 19.429 0 243.397 243.397 0 88.433 GT-1 75.047 69.274 50.000 40.929 0 207.449 207.449 0 149.729 GT-3 75.505 69.697 50.600 62.429 0 171.479 171.479 0 211.075 GT-4 75.961 70.118 51.200 83.928 0 135.488 135.488 0 272.473 GT-5 76.420 70.542 51.900 105.428 0 99.543 99.543 0 333.762 GT-6 76.875 70.962 52.500 126.926 0 63.511 63.511 0 395.258 GT-7 77.329 71.380 53.100 148.425 0 27.460 27.460 0 456.800

[0130] Table 16 Furnace grade, charge structure and vanadium-titanium ore ratio at different slag-iron ratios under fixed vanadium-titanium ore 2 dosage

[0131]

[0132] Table 17 Composition of slag and molten iron at different slag-iron ratios under fixed vanadium-titanium ore 2 dosage (%)

[0133] Solution No. CaO <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[R2]]> <![CDATA[R3]]> [V] GT-1 25.03 23.83 11.16 12.98 22.50 1.05 1.52 0.289 GT-1 25.14 23.95 10.91 13.00 22.50 1.05 1.51 0.295 GT-3 25.26 24.06 10.68 13.01 22.50 1.05 1.49 0.301 GT-4 25.37 24.16 10.45 13.02 22.50 1.05 1.48 0.307 GT-5 25.47 24.26 10.23 13.04 22.50 1.05 1.47 0.314 GT-6 25.58 24.36 10.02 13.05 22.50 1.05 1.46 0.320 GT-7 25.67 24.45 9.81 13.06 22.50 1.05 1.45 0.326

[0134] Table 18 Sinter composition and basicity at different slag-iron ratios with fixed vanadium-titanium ore 2 dosage

[0135] Solution No. TFe FeO <![CDATA[Fe2O3]]> CaO <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[V2O5]]> P S RO GT-1 51.00 8.45 63.47 12.58 5.92 3.08 1.80 2.88 0.15 0.023 0.019 2.13 GT-1 50.25 8.45 62.40 12.72 6.13 3.02 1.91 3.08 0.16 0.025 0.021 2.08 GT-3 49.53 8.45 61.37 12.87 6.33 2.96 2.02 3.27 0.17 0.028 0.023 2.03 GT-4 48.82 8.45 60.36 13.00 6.53 2.90 2.12 3.46 0.19 0.030 0.025 1.99 GT-5 48.14 8.45 59.38 13.14 6.72 2.85 2.23 3.65 0.20 0.033 0.027 1.95 GT-6 47.47 8.45 58.43 13.27 6.91 2.80 2.33 3.83 0.21 0.035 0.029 1.92 GT-7 46.82 8.45 57.50 13.40 7.10 2.75 2.42 4.00 0.23 0.038 0.031 1.89

[0136] Table 19 Pig iron cost at different slag-iron ratios with fixed vanadium-titanium ore 2 dosage (yuan / ton)

[0137]

[0138]

[0139] 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 method for blending iron ore for smelting high-titanium vanadium-titanium ore in a blast furnace, characterized in that: The process includes: (1) Establishment of ore blending model for blast furnace smelting of high-titanium vanadium-titanium ore: (1.1) Iron balance: From the Fe element balance we can get: ∑[x i ×w(Fe) i ]+∑[x f ×w(Fe) f ]+∑[x j ×w(Fe) j ]=1000×w(Fe)+μ·w(Fe) z +x c ·w(Fe) c (1); In formula (1): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, unit: kg / t; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j is the amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④μ is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; ⑤x C The amount of dust generated by the blast furnace process per ton of iron, in kg / t; ⑥w(Fe) i 、w(Fe) f 、w(Fe) j 、w(Fe) Z 、w(Fe) C It is the Fe content of different iron ores, fuels in the sintering process, other iron ores, slag and dust in the blast furnace process; From formula (1), we can get: ∑(x i ·w(Fe) i )=1000×w(Fe)+x z ·w(Fe) z +x c ·w(Fe) c -∑[x f ·w(Fe) f ]-∑[x j ·w(Fe) j ] (2); In formula (2), let: w(Fe) i =k 1i (3); 1000×w(Fe)+x z ·w(Fe) z +x c ·w(Fe) c -∑[x f ·w(Fe) f ]-∑[x j ·w(Fe) j ]=λ1 (4); We can get: ∑(k 1i ×x i )=λ1 (5); (1.2) Slag balance: From the mass balance of slag-forming components in the slag, we can get: In formula (6): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, unit: kg / t; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j is the amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④μ is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; ⑤x C The amount of dust generated by the blast furnace process corresponding to a ton of iron, unit: kg / t; ⑥δ i ,δ f ,δ c ,δ j They are the sum of the mass contents of CaO, SiO2, MgO, Al2O3 and TiO2 in different iron ores, fuel, furnace dust in the blast furnace process and other iron ores in the blast furnace process; ⑦[Si] and [Ti] are the mass contents of Si and Ti in molten iron respectively; ⑧ξ is the sum of the mass contents of CaO, SiO2, MgO, Al2O3 and TiO2 in the slag; ⑨μ is the slag-iron ratio, unit: kg / t; From formula (6), we can get: In formula (7), let: d i =k 2i (8); We can get: ∑(k 2i ×x i )=λ2 (10); (1.3) Slag binary basicity R2 balance: From the binary alkalinity R2 balance, we can get: After sorting, we can get: In formula (12): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, unit: kg / t; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j The amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④x C The amount of dust produced by the blast furnace process per ton of iron, in kg / t; ⑤w(CaO) i 、w(CaO) f 、w(CaO) j 、w(CaO) C are the CaO mass contents in different iron ores, fuels, other iron ores and furnace dust in the sintering process; ⑥w(SiO2) i 、w(SiO2) f 、w(SiO2) j 、w(SiO2) C are the mass content of SiO2 in different iron ores, fuels, other iron ores in blast furnace processes and furnace dust; ⑦[Si] is the mass content of Si in molten iron; ⑧R2 is the binary basicity of slag; In formula (12): in(CaO) i -R2 w(SiO2) i =k 3i (13); We can get: ∑(k 3i ×x i )=λ3 (15); (1.4) TiO2 balance From the TiO2 balance, we can get: In formula (16): ①x i The amount of different iron ores consumed in the sintering process corresponding to a ton of iron, unit: kg / t; ②x f The amount of fuel consumed in the blast furnace process per ton of iron, in kg / t; ③x j is the amount of other iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ④μ is the amount of slag produced in the blast furnace process corresponding to a ton of iron, in kg / t; ⑤x C The amount of dust produced by the blast furnace process per ton of iron, in kg / t; ⑥w(TiO2) i 、w(TiO2) f 、w(TiO2) c 、w(TiO2) j 、w(TiO2) μ are the TiO2 mass content of different iron ores, fuels, furnace dust, other iron ores and slag in blast furnace processes; ⑦[Ti] is the Ti mass content of molten iron; By rearranging formula (16), we can get: In formula (17), let: in(TiO2) i =k 4i in(TiO2) i =k 4i (18); We can get: ∑(k 4i ×x i )=λ4 (20); (1.5) Iron ore consumption: From equations (5), (10), (15), and (20), we can obtain the following linear equations: By solving the linear equation group (21), the amount of different iron ores in the sintering process per ton of iron is obtained; according to the calculation result of equation (21), the chemical composition and amount of the sintered ore are obtained through the sintered ore chemical composition calculation model; (2) Determination of the chemical composition of sintered ore and the amount of fuel used in the sintering process: (2.1) The chemical composition of the sintered ore produced by the sintering process is calculated by the following formula: Y i =x i ·(1-Ig xi -S xi ·D Sxi ) (22); In formulas (22) to (24), Yi is the burnout of a certain raw material or fuel in the sintering process, in kg / kg; x i The amount of a certain raw material or fuel used in the sintering process per ton of pig iron, in kg / t; Ig xi It is the burning loss value of a certain raw material or fuel in the sintering process; S xi The sulfur content of a raw material or fuel in the sintering process; D Sxi is the desulfurization rate of a certain raw material or fuel in the sintering process; Cxi is the mass content of a certain component in a certain raw material or fuel in the sintering process; C i is the mass percentage of a component in the sintered ore; S i is the sulfur mass percentage of the sintered ore; (2.2) Determination of fuel consumption in sintering process: The amount of fuel used in the sintering process needs to be set to an initial value first; from this initial value, the chemical composition of the sintered ore and the proportion of pellets under certain conditions are calculated; if the ratio of this initial value to other raw materials in the sintering process does not meet the set value, the amount of fuel is adjusted according to the calculation until the ratio of fuel to raw material reaches the set value; (3) Calculation of vanadium-titanium ore ratio: The ratio of vanadium-titanium ore is the mass fraction of vanadium-titanium ore in all iron-containing raw materials: In formula (25), x iV-T The amount of vanadium-titanium ore used in different sintering and blast furnace processes per ton of iron, unit: kg / t; x i The amount of different types of iron ore used in sintering and blast furnace processes, in kg / t; (4) Calculation of furnace grade: The charging grade is the ratio of the product of the mass of the iron-containing charge used in the blast furnace and its iron grade to the total mass of the iron-containing charge: In formula (26), xj is the mass of the iron-containing raw material used in the blast furnace process per ton of iron, in kg / t; TFej is the iron grade of the above iron-containing raw material; (5) Calculation of pig iron cost: ∑(P p +P m )·x i +P J ·x J +P M ·x M +∑(P j ·x j )=P t (27); In formula (27): ①P p and P m are the purchase price and processing cost of iron ore and flux in the sintering process, respectively, in RMB / ton; ②x i The quantity of iron ore and flux consumed in the sintering process corresponding to a ton of iron, in kg / t; ③P J , P M , P j are the prices of coke, PCI and other iron ore in blast furnace process, in Yuan / ton; ④x J The amount of coke consumed per unit of pig iron, in kg / t; ⑤x M The amount of PCI coal consumed per unit of pig iron, in kg / t; ⑥x j The amount of iron ore consumed in the blast furnace process corresponding to a ton of iron, in kg / t; ⑦P t Total cost of raw fuel per ton of iron, unit: Yuan / ton.

2. The iron ore blending method according to claim 1, characterized in that: Also includes: According to the amount of iron ore used in the sintering process, the amount and price of blast furnace acid burning, blast furnace pellets, coke, and pulverized coal injection, the proportion of vanadium-titanium ore and the cost of ore blending under different conditions are calculated.

3. The iron ore blending method according to claim 2, characterized in that: When calculating the proportion of vanadium-titanium ore and the blending cost under the different conditions, among the three factors of slag-iron ratio μ, slag TiO2 content, and slag binary basicity R2, the other two factors are first fixed, and only the impact of the change of one factor is examined.

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