Burdening method of blast furnace charging material containing acid sinter

Abstract

The invention provides a burdening method of a blast furnace charging material containing acid sinter, and relates to the technical field of metallurgy. Comprising the following steps: S1, producing acidic sintered ore and high-alkalinity vanadium-titanium sintered ore through a sintering machine; s2, the two kinds of sintered ore form mixed sintered ore; and S3, setting the charging material proportion of the blast furnace according to 68-72% of the mixed sintering ore, 25-30% of the pellet ore and 1-3% of the lump ore, two kinds of sintering ore with different properties are alternately produced through one sintering machine, and the mixed sintering ore is formed by the acid sintering ore and the high-alkalinity vanadium-titanium sintering ore through sintering control over the acid sintering ore in the production process. The alkalinity of the high-alkalinity vanadium-titanium sinter can be controlled to be 2.0 times or above, the quality of the sinter can be improved, meanwhile, by adding the acid sinter into the blast furnace charging material, the total adding proportion of the sinter is increased to about 70% from 65% under the condition that the alkalinity of the furnace slag is kept, the structure of the blast furnace charging material is optimized, and the comprehensive charging material quality is optimized; and stable and smooth operation of the blast furnace and molten iron cost reduction are facilitated, and economic benefits are obvious.

Description

Technical Field

[0001] The present application relates to the field of metallurgical technology, and in particular to a method for batching blast furnace charges containing acidic sintered ore. Background Art

[0002] Sintered ore can be divided into three categories according to the different binary basicity: acidic, self-fluxing, and alkaline. Among the basic sintered ore, the one with alkalinity greater than 1.80 times is high-basicity sintered ore. Long-term ironmaking production practice shows that high-basicity sintered ore not only has high mechanical strength, but also has excellent metallurgical properties. It is the mainstream product of modern sintering production. Acidic sintered ore is generally not used in blast furnace production due to its relatively poor quality.

[0003] When vanadium-titanium ore is smelted in a blast furnace, due to the presence of TiO2 in vanadium-titanium sinter, its quality index is significantly lower than that of ordinary sinter. According to the mineralization mechanism and production practice of vanadium-titanium sinter, as long as a certain binary basicity is guaranteed, the physical and metallurgical properties of vanadium-titanium sinter can be guaranteed to meet the needs of the blast furnace. However, after the basicity of vanadium-titanium sinter is increased, the blast furnace machine-sintering ratio will drop significantly, the sintering capacity cannot be fully utilized, and there are unreasonable contradictions in the blast furnace charge structure. Therefore, in theory, part of the acidic sinter can be used in the blast furnace charge structure to meet the balance between sintering output and blast furnace usage, so that the blast furnace charge structure is optimized, while ensuring a certain basicity of vanadium-titanium sinter, thereby ensuring the quality of the sinter.

[0004] In view of this, the present application aims to provide a method for proportioning blast furnace charge containing acidic sintered ore, so as to solve the problem of proportioning blast furnace charge containing acidic sintered ore. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a method for batching blast furnace charges containing acidic sintered ore, which can solve the technical problem of batching blast furnace charges containing acidic sintered ore.

[0006] The present application provides a method for batching blast furnace charge containing acidic sintered ore, comprising the following steps:

[0007] S1. Produce two types of sintered ores, namely, acidic sintered ore and high basicity vanadium-titanium sintered ore, by one sintering machine;

[0008] S2. The acidic sinter produced is mixed with the high basicity vanadium-titanium sinter to form a sintered ore;

[0009] S3. Set the blast furnace charge ratio according to 68-72% of mixed sintered ore, 25-30% of pelletized ore and 1-3% of lump ore.

[0010] Furthermore, in step S1, the content of the ingredients of the acidic sintered ore is 59-60% of mixed ore powder, 1.5-2.5% of quicklime powder, 1.5-2.0% of dolomite powder, 3-3.5% of coke powder, and 30-35% of returned ore; the content of the ingredients of the high-alkalinity vanadium-titanium sintered ore is 50-53% of mixed ore powder, 4-4.3% of quicklime powder, 2.4-2.5% of limestone powder, 6.3-6.8% of dolomite powder, 3.3-3.5% of coke powder, and 30-31% of returned ore.

[0011] Furthermore, in step S1, according to the component ratio for producing acidic sintered ore and high basicity vanadium-titanium sintered ore, a combination of pile-building and direct feeding is adopted to carry out sintering production, and when the acidic sintered ore and high basicity vanadium-titanium sintered ore are switched to production, the material layer is lowered by about 50 mm about 10 minutes in advance; when the high basicity vanadium-titanium sintered ore and acidic sintered ore are switched to production, the material layer is raised by about 50 mm about 10 minutes in advance.

[0012] Furthermore, in step S1, when the production of acidic sintered ore and high-basicity vanadium-titanium sintered ore is switched, 5%-20% of vanadium-titanium powder is gradually added to the acidic sintered ore ingredients.

[0013] Furthermore, in step S1, the basicity of the acidic sintered ore is controlled at 1.0 times, and the MgO is controlled at 1.5%-1.7%.

[0014] Furthermore, in step S1, the FeO content of the acidic sintered ore is controlled at 10%-12%, and the sintering end temperature is controlled at ≥370°C.

[0015] Furthermore, in step S1, the negative pressure of exhaust during the sintering process of the acidic sintered ore is controlled at 15.5-16.5 KPa, and the thickness of the material layer is controlled at 580 mm-600 mm.

[0016] Furthermore, in step S1, during the sintering process of the acidic sintered ore, φ25 ordinary steel loosening rods are used for the material layer to increase the material layer thickness, and the blast furnace gas flame length is adjusted within the range of 300mm-50mm, and the edge coke oven gas ignition is increased to ensure the ignition effect.

[0017] Furthermore, in step S1, the chemical composition of the acidic sintered ore produced is TFe 57.59%, FeO 10.29%, SiO2 6.38%, Al2O3 2.67%, MgO 1.59%, V2O5 0.15%, TiO2 1.66%, and R2 0.88%; the chemical composition of the high-basicity vanadium-titanium sintered ore produced is TFe 51.31%, FeO 9.2%, SiO2 6.03%, Al2O3 2.39%, MgO 2.85%, V2O5 0.17%, TiO2 2.13%, and R22%.

[0018] Furthermore, in step S1, the drum index of the produced acidic sintered ore is ≥71%, the low-temperature reduction pulverization index is ≥45%, and the reducibility is ≥73%.

[0019] Beneficial effects of the present invention:

[0020] The present invention provides a method for batching blast furnace charges containing acidic sintered ore, comprising the steps of: S1. producing two types of sintered ores, namely, acidic sintered ore and high-basicity vanadium-titanium sintered ore, by a sintering machine; S2. forming a mixed sintered ore from the produced acidic sintered ore and the high-basicity vanadium-titanium sintered ore; S3. setting the blast furnace charge ratio according to 68-72% of the mixed sintered ore, 25-30% of the pelletized ore and 1-3% of the lump ore. The present invention uses a sintering machine to alternately produce two types of sintered ores with different properties to meet the use requirements of the blast furnace, and The sintering of acidic sintered ore is controlled during the production process, and it is mixed with high-basicity vanadium-titanium sintered ore to form a mixed sintered ore, so that the basicity of the high-basicity vanadium-titanium sintered ore can be controlled at more than 2.0 times, which is beneficial to improving the quality of the sintered ore. At the same time, by adding acidic sintered ore to the blast furnace charge, while maintaining the slag basicity, the total proportion of sintered ore is increased from 65% to about 70%, the blast furnace charge structure is optimized, and the comprehensive charge quality is optimized, which is beneficial to the stable operation of the blast furnace and the reduction of molten iron costs, with obvious economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a flow chart of ingredients preparation in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0026] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] See also Figure 1 As shown, the method for batching blast furnace charging materials containing acidic sintered ore provided in this embodiment comprises the following steps:

[0030] S1. Produce two types of sintered ores, namely, acidic sintered ore and high basicity vanadium-titanium sintered ore, by one sintering machine;

[0031] S2. The produced acidic sintered ore 20% and high basicity vanadium titanium sintered ore 80% constitute a mixed sintered ore;

[0032] S3. Set the blast furnace charge ratio according to 70% of mixed sintered ore, 28% of pelletized ore and 2% of lump ore.

[0033] Specifically, in step S3, the chemical composition of the pellets and lump ore is shown in the following table:

[0034] Mineral Type TFe <![CDATA[SiO2]]> <![CDATA[Al2O3]]> CaO MgO S P <![CDATA[TiO2]]> <![CDATA[V2O5]]> Pelletized Ore 53.45 6.27 2.99 1.2 2.71 0.011 0.021 9.5 0.605 Lump Ore 58.69 4.86 2.86 0.03 0.1 0.032 0.04 0 0

[0035] Among them, in step S1, the ingredient components of the acidic sintered ore are 59.87% mixed ore powder, 2% quicklime powder, 1.8% dolomite powder, 3.33% coke powder, and 33% returned ore; the ingredient components of the high-alkalinity vanadium-titanium sintered ore are 52.61% mixed ore powder, 4.1% quicklime powder, 2.43% limestone powder, 6.5% dolomite powder, 3.36% coke powder, and 31% returned ore.

[0036] Among them, in step S1, according to the component ratio of producing acidic sintered ore and high-basicity vanadium-titanium sintered ore, the material is fed by a combination of pile building and direct feeding to carry out sintering production, so as to solve the problems of iron ore powder feeding and sintered ore discharge, and when the acidic sintered ore and high-basicity vanadium-titanium sintered ore are switched to production, the material layer is lowered by about 50 mm about 10 minutes in advance.

[0037] Among them, in step S1, the initial feeding amount of the two sintered ores and the normal feeding amount after the switching are completed are first determined in the batching room during the sintering process. When the switching process on the sintering machine is to produce acidic sintered ore and high-alkalinity vanadium-titanium sintered ore, 5%-20% vanadium-titanium powder is gradually added to the acidic sintered ore batching.

[0038] In step S1, the basicity of the acidic sintered ore is controlled at 1.0 times, and the MgO is controlled at 1.5%-1.7% to maximize the use of quicklime powder, ensure the temperature of the mixed material and the granulation effect, and improve the air permeability of the sintering machine upper layer;

[0039] Among them, in step S1, the FeO content of the acidic sintered ore is controlled at 10%-12%, and the sintering end temperature is controlled at ≥370°C. Due to the low basicity of the acidic sintered ore, the calcium ferrite content of the sintered ore mineral composition is extremely low, and the strength of the sintered ore is poor. By controlling the FeO content at 10%-12% and the sintering end temperature at ≥370°C, both the strength of the sintered ore and a certain reducibility are guaranteed.

[0040] Among them, in step S1, the exhaust negative pressure during the sintering process of acidic sintered ore is controlled at 15.5-16.5KPa, and the material layer thickness is controlled at 580mm-600mm. Due to the low alkalinity of acidic sintered ore, the material layer has poor permeability. Through the model and production practice, it is determined that the exhaust negative pressure is controlled at 15.5-16.5KPa and the material layer is controlled at 580mm-600mm, which not only meets the requirements of sintered ore quality, but also effectively controls the serious problem of two-level differentiation of acidic sintered ore particle size.

[0041] Among them, in step S1, during the sintering process of the acidic sintered ore, a φ25 ordinary steel loosening rod is used for the material layer to increase the material layer thickness, and the blast furnace gas flame length is adjusted, and the edge coke oven gas ignition is increased to ensure the ignition effect. The material layer thickness of the acidic sintered ore and the high-basicity vanadium-titanium sintered ore is quite different. When producing acidic sintered ore, the material layer is relatively low, the ignition depth is insufficient, resulting in insufficient ignition intensity, and the sintering process cannot proceed normally. The material layer thickness is increased by using the loosening rod for the material layer; the blast furnace gas flame length is adjusted within the adjustment range of 300mm-50mm, and the edge coke oven gas ignition is increased to ensure the ignition effect.

[0042] Among them, in step S1, the chemical composition of the acidic sintered ore produced is TFe 57.59%, FeO 10.29%, SiO2 6.38%, Al2O3 2.67%, MgO 1.59%, V2O5 0.15%, TiO2 1.66%, and R2 0.88%; the chemical composition of the high-basicity vanadium-titanium sintered ore produced is TFe 51.31%, FeO 9.2%, SiO2 6.03%, Al2O3 2.39%, MgO 2.85%, V2O5 0.17%, TiO2 2.13%, and R22%.

[0043] Wherein, in step S1, the drum index of the produced acidic sintered ore is ≥71%, the low-temperature reduction pulverization index is ≥45%, and the reducibility is ≥73% to meet the requirements of blast furnace use.

[0044] In this embodiment, the physical and metallurgical properties of the produced acidic sintered ore are shown in the following table:

[0045]

[0046] As a comparative example, the acidic sintered ore was not added, and the vanadium-titanium sintered ore was added to the blast furnace feed, wherein the composition ratio of the vanadium-titanium sintered ore is as shown in the following table:

[0047]

[0048] The chemical composition of vanadium-titanium sinter is as follows:

[0049]

[0050] In this comparative example, the blast furnace feed ratio is 65% of vanadium-titanium sintered ore, 33% of pelletized ore, and 2% of lump ore.

[0051] After testing, it is found that in this embodiment, a certain proportion of acidic sintered ore is added to the ore fed into the blast furnace. Under the condition of maintaining a certain slag basicity, the total proportion of sintered ore is increased from 65% to 70%, the ore structure fed into the blast furnace is optimized, and the comprehensive charge quality is optimized, which is beneficial to the stable operation of the blast furnace and the reduction of molten iron cost. At the same time, a certain proportion of acidic sintered ore is added to the ore fed into the blast furnace, and the alkalinity of high-alkalinity vanadium-titanium sintered ore can be controlled at more than 2.0 times, which is beneficial to the improvement of the quality of sintered ore. In the comparative example, acidic sintered ore is not added to the ore fed into the blast furnace. Under the condition of maintaining a certain slag basicity, if the sintered ore ratio of 70% is to be achieved, the alkalinity of the sintered ore must be controlled at about 1.78%, and the quality of the sintered ore cannot be guaranteed, which is not conducive to the stable and smooth operation of the blast furnace.

[0052] In summary, the present application uses a sintering machine to alternately produce two sintered ores with different properties to meet the use needs of the blast furnace, and through the sintering control of the acidic sintered ore in the production process, it is formed into a mixed sintered ore with the high-alkalinity vanadium-titanium sintered ore, so that the alkalinity of the high-alkalinity vanadium-titanium sintered ore can be controlled to be more than 2.0 times, which is beneficial to the improvement of the quality of the sintered ore. At the same time, by adding the acidic sintered ore to the blast furnace charge, while maintaining the slag alkalinity, the total proportion of sintered ore added is increased from 65% to about 70%, the blast furnace charge structure is optimized, and the comprehensive charge quality is optimized, which is beneficial to the stable operation of the blast furnace and the reduction of molten iron costs, with obvious economic benefits.

[0053] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for batching blast furnace charge containing acidic sintered ore, characterized in that: The following steps are involved: S1. Produce two types of sintered ores, namely, acidic sintered ore and high basicity vanadium-titanium sintered ore, by one sintering machine; S2. The acidic sinter produced is mixed with the high basicity vanadium-titanium sinter to form a sintered ore; S3. Set the blast furnace charge ratio according to 68-72% of mixed sintered ore, 25-30% of pelletized ore and 1-3% of lump ore.

2. The method for batching blast furnace charge containing acidic sintered ore according to claim 1, characterized in that: In step S1, the content of the ingredients of the acidic sintered ore is 59-60% of mixed ore powder, 1.5-2.5% of quicklime powder, 1.5-2.0% of dolomite powder, 3-3.5% of coke powder, and 30-35% of returned ore; the content of the ingredients of the high-basicity vanadium-titanium sintered ore is 50-53% of mixed ore powder, 4-4.3% of quicklime powder, 2.4-2.5% of limestone powder, 6.3-6.8% of dolomite powder, 3.3-3.5% of coke powder, and 30-31% of returned ore.

3. The method for batching blast furnace charge containing acidic sintered ore according to claim 2, characterized in that: In step S1, according to the component ratio of producing acidic sintered ore and high basicity vanadium-titanium sintered ore, the material is fed by a combination of pile building and direct feeding to carry out sintering production, and when the acidic sintered ore and high basicity vanadium-titanium sintered ore are switched to production, the material layer is lowered by about 50 mm about 10 minutes in advance; when the production of high basicity vanadium-titanium sintered ore and acidic sintered ore is switched to production, the material layer is raised by about 50 mm about 10 minutes in advance.

4. The method for batching blast furnace charge containing acidic sintered ore according to claim 3, characterized in that: In step S1, when the production of acidic sintered ore and high-basicity vanadium-titanium sintered ore is switched, 5%-20% of vanadium-titanium powder is gradually added to the acidic sintered ore batching.

5. The method for batching blast furnace charge containing acidic sintered ore according to claim 4, characterized in that: In step S1, the basicity of the acidic sintered ore is controlled at 1.0 times, and the MgO is controlled at 1.5%-1.7%.

6. The method for batching blast furnace charge containing acidic sintered ore according to claim 5, characterized in that: In step S1, the FeO content of the acidic sintered ore is controlled at 10%-12%, and the sintering end temperature is controlled at ≥370°C.

7. The method for batching blast furnace charge containing acidic sintered ore according to claim 6, characterized in that: In step S1, the negative pressure of exhaust during the sintering process of the acidic sintered ore is controlled at 15.5-16.5 KPa, and the thickness of the material layer is controlled at 580 mm-600 mm.

8. The method for batching blast furnace charge containing acidic sintered ore according to claim 7, characterized in that: In step S1, during the sintering process of the acidic sintered ore, φ25 ordinary steel loosening rods are used for the material layer to increase the material layer thickness, and the blast furnace gas flame length is adjusted within the range of 300mm-50mm, and the edge coke oven gas ignition is increased to ensure the ignition effect.

9. The method for batching blast furnace charge containing acidic sintered ore according to claim 8, characterized in that: In step S1, the chemical composition of the produced acidic sintered ore is TFe 57.59%, FeO 10.29%, SiO2 6.38%, Al2O3 2.67%, MgO 1.59%, V2O5 0.15%, TiO2 1.66%, and R2 0.88%; the chemical composition of the produced high-basicity vanadium-titanium sintered ore is TFe 51.31%, FeO 9.2%, SiO2 6.03%, Al2O3 2.39%, MgO 2.85%, V2O5 0.17%, TiO2 2.13%, and R22%.

10. The method for batching blast furnace charge containing acidic sintered ore according to claim 8, characterized in that: In step S1, the drum index of the produced acidic sintered ore is ≥71%, the low-temperature reduction pulverization index is ≥45%, and the reducibility is ≥73%.

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