A method for early warning and treatment of vanadium-titanium magnetite blast furnace hearth accumulation

Abstract

The present application provides a kind of early warning and processing method of vanadium-titanium magnetite blast furnace hearth accumulation, when the following steps are executed during the tapping of blast furnace: the first content of carbon in molten iron and the second content of carbon are detected, the first content of carbon is compared with threshold range, and the second content of carbon is compared with minimum threshold value;In response to the comparison result of the first content of carbon and threshold range, the comparison result of the second content of carbon and minimum threshold value, the titanium content and silicon content in molten iron are detected, and the average value of the difference between titanium content and silicon content is compared with difference threshold value;Determine whether the hearth accumulation occurs based on the above comparison result.The method of the present application can distinguish and early warning whether the center of hearth occurs slight accumulation, timely take corresponding effective technical measures, eliminate hearth accumulation, prevent blast furnace center accumulation aggravation, help blast furnace operator to achieve early detection, early adjustment, less adjustment, promote long-term stable operation of blast furnace.

Description

Technical Field

[0001] This invention belongs to the field of blast furnace ironmaking technology, specifically relating to a method for early warning and handling of vanadium-titanium magnetite blast furnace hearth accumulation based on changes in the carbon content of molten iron. Background Technology

[0002] In blast furnace smelting, the hearth is the primary area for heat transfer and generation, serving as the driving force for the downward movement and reduction of the blast furnace burden. Therefore, the hearth's operating condition is fundamental to stable and efficient blast furnace production. In the blast furnace smelting of vanadium-titanium magnetite, the downward-moving iron-containing burden and the upward-moving high-temperature gas complete heat transfer and reduction reactions in their counter-current motion. As the reduction reaction progresses, while iron is reduced, elements such as Ti, Si, and V are also reduced into the molten iron, simultaneously undergoing carburization. Therefore, the levels of Ti, Si, and C in the molten iron, along with its physical temperature, comprehensively reflect the final thermal state of the blast furnace, the effectiveness of heat exchange, and the hearth's operating condition. Among these, the Ti and Si content in the molten iron is often more sensitive to temperature changes and is used to characterize the furnace temperature variations during vanadium-titanium magnetite blast furnace smelting; this is known as chemical temperature.

[0003] However, the following problems may arise during the production process: First, for blast furnace smelting of vanadium-titanium magnetite, the optimal requirement is to achieve "physical heat and chemical coolness," that is, to have a higher physical temperature of slag and iron and lower levels of components such as Ti and Si that represent chemical temperature. Essentially, this aims to reduce the over-reduction of TiO2 and avoid the formation of excessive high-melting-point titanium carbonitride. Conversely, this illustrates the contradiction between physical temperature and chemical temperature used to characterize the thermal state of the hearth. In actual production, the physical temperature of molten iron measured by contact thermocouples and the Ti and Si values ​​of molten iron often show a weak linear correlation. Second, when accumulation occurs in the center of the blast furnace hearth and the permeability of the central material column deteriorates, the physical and chemical temperatures of the slag and iron are often high in the early stage of slag and iron tapping, and the furnace temperature drops sharply in the later stage of slag and iron tapping. Alternatively, the slag and iron furnace temperature of this batch may be low. After taking measures such as adding coke to increase the furnace temperature, the slag and iron temperature of the next batch rises sharply. Such rapid and significant changes in furnace temperature often lead to production accidents such as blast furnace slippage and hanging. The reason why the chemical and physical temperatures, when they accumulate in the center of the hearth, cannot effectively reflect the true thermal state of the hearth is mainly due to the following reasons: Firstly, in order to control the amount of titanium carbonitride generated, the physical temperature control range of vanadium-titanium magnetite blast furnace smelting is narrow, which affects the effective correspondence between physical and chemical temperatures. Secondly, after the accumulation occurs in the center of the hearth, the porosity of the coke column is low, and a large amount of molten iron only accumulates in the limited area between the hearth wall and the coke column. The slag-iron flow and heat exchange in the hearth are insufficient, and the overall heat storage of the hearth is also insufficient, resulting in a large fluctuation in furnace temperature before and after slag and iron tapping.

[0004] Therefore, it is essential to explore a method that can more accurately reflect the thermal state of the blast furnace hearth, especially when slight accumulation begins to appear in the center of the hearth and the accumulation becomes more severe, in order to address hearth accumulation as early as possible. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for early warning and handling of vanadium-titanium magnetite blast furnace hearth buildup based on changes in the carbon content of molten iron.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This invention provides a method for early warning and handling of vanadium-titanium magnetite ore buildup in the hearth of a blast furnace. The method involves the following steps during blast furnace tapping:

[0008] The first and second carbon contents in molten iron are detected. The first carbon content is compared with a threshold range, and the second carbon content is compared with a minimum threshold.

[0009] In response to the comparison results of the first carbon content with the threshold range and the comparison results of the second carbon content with the minimum threshold, the titanium content and silicon content in the molten iron are detected, and the average value of the difference between the titanium content and the silicon content is compared with the difference threshold.

[0010] Based on the above comparison results, determine whether there is hearth buildup.

[0011] Furthermore, the detection of the first carbon content, the second carbon content, the titanium content, and the silicon content in molten iron includes the following steps:

[0012] The carbon, titanium, and silicon content of molten iron in each of M consecutive heats from N groups was measured.

[0013] Obtain the average carbon content in the molten iron from M heats to get the first carbon content;

[0014] Obtain the minimum carbon content in M ​​consecutive batches of molten iron from N groups to obtain the second carbon content;

[0015] Obtain the difference between the titanium content and the silicon content in the molten iron of each of the M heats, and then calculate the average value to obtain the average value of the difference between the titanium content and the silicon content.

[0016] Furthermore, no buildup will occur in the hearth if the following conditions are met:

[0017] In N consecutive groups, the first carbon content is within the first threshold range, and the second carbon content is greater than or equal to the first minimum threshold.

[0018] Furthermore, no buildup will occur in the hearth if the following conditions are met:

[0019] In N consecutive groups, the first carbon content is within the second threshold range, and the second carbon content is greater than or equal to the second minimum threshold.

[0020] Furthermore,

[0021] If the average difference between the titanium content and the silicon content is greater than or equal to the first difference threshold, then no measures need to be taken for the furnace hearth.

[0022] If the average difference between the titanium content and the silicon content is less than the first difference threshold, then the first measure must be taken for the furnace hearth:

[0023] Increase the intensity of raw materials entering the furnace;

[0024] If the intensity of raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 3%.

[0025] Furthermore, a slight buildup in the hearth will trigger an alarm if the following conditions are met:

[0026] In N consecutive groups, the first carbon content is within the third threshold range, and the second carbon content is greater than or equal to the third minimum threshold.

[0027] Furthermore,

[0028] If the average difference between the titanium content and the silicon content is greater than or equal to the second difference threshold, then a second measure needs to be taken for the furnace hearth:

[0029] Increasing the intensity of raw materials fed into the furnace reduces coke load by 3%;

[0030] If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5% and the ore batch weight will be reduced by 3%.

[0031] If the average difference between the titanium content and the silicon content is less than the second difference threshold, then a third measure needs to be taken for the furnace hearth:

[0032] Increase the intensity of raw materials and fuels fed into the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase the proportion of iron-manganese ore fed into the furnace by 2% in the furnace charge structure, with MnO ≥ 10% in the iron-manganese ore;

[0033] If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and 3% iron-manganese ore will be added to the furnace charge structure.

[0034] Furthermore, if the following conditions are met, severe buildup in the hearth will trigger an early warning:

[0035] In N consecutive groups, the first carbon content is within the fourth threshold range.

[0036] Furthermore,

[0037] If the average difference between the titanium content and the silicon content is greater than or equal to the second difference threshold, then a fourth measure needs to be taken for the furnace hearth:

[0038] Increase the intensity of raw materials and fuels entering the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase iron-manganese ore by 3% in the furnace charge structure;

[0039] If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and 3% iron-manganese ore and 2% fluorite will be added to the furnace charge structure.

[0040] If the average difference between the titanium content and the silicon content is less than the second difference threshold, then a fifth measure needs to be taken for the furnace hearth:

[0041] Increase the intensity of raw materials fed into the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase the proportion of iron-manganese ore and fluorite in the furnace charge structure by 3%;

[0042] If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and the furnace charge structure will be increased by 3% for iron-manganese ore and 3% for fluorite.

[0043] Furthermore, the sampling point for molten iron is kept at the same location, and sampling is carried out 20 to 30 minutes after tapping.

[0044] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0045] The method of this invention is based on the change in carbon content in molten iron, and combined with the changes in titanium and silicon content in molten iron according to the actual situation. It can identify and warn of slight accumulation in the center of the hearth when slight accumulation occurs in the blast furnace during the smelting of vanadium-titanium magnetite ore, while other indicators do not show effective changes in time. It can understand the working status of the hearth in time, so as to take corresponding effective technical measures in a timely manner to eliminate hearth accumulation, prevent the accumulation in the center of the blast furnace from becoming more serious, avoid aggravating the fluctuation of furnace conditions, reduce the huge waste of resources and economic losses caused by the fluctuation of furnace conditions, help blast furnace operators to detect early, adjust early, and reduce the need for adjustment, and promote the long-term stable operation of the blast furnace. Attached Figure Description

[0046] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic flowchart illustrating the method for early warning and handling of vanadium-titanium magnetite blast furnace hearth accumulation according to the present invention.

[0048] Figure 2 This is another schematic flowchart of the method for early warning and handling of vanadium-titanium magnetite blast furnace hearth accumulation according to the present invention. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to specific examples and the accompanying drawings.

[0050] In the complex production reaction process of a blast furnace, the entire furnace, from the hearth to the top, is supported by a coke column as a "skeleton." Therefore, the carburizing process of the reduced iron continues continuously from the top to the hearth. The final carburizing process of molten iron in the blast furnace is influenced by the blast furnace smelting temperature, carburizing time, coke porosity, furnace charge characteristics, and other components of the molten iron. When the furnace temperature control range is narrow, the furnace charge characteristics are relatively stable, and the smelting intensity is similar, if the porosity of the coke column in the center of the blast furnace decreases, and the permeability of the column in the central region of the blast furnace decreases, for vanadium-titanium magnetite blast furnace smelting, not only will high-melting-point titanium carbonitride be generated in the hearth center, but the graphitization degree and carbon deposition of the coke in the hearth center will also deepen, reducing the carburizing rate of the molten iron and lowering its carbon content. Therefore, the carbon content of the molten iron reflects the accumulation state in the hearth. Based on the continuous change in the carbon content of the molten iron, early warning of hearth accumulation behavior can be provided, allowing blast furnace operators to take appropriate measures to promptly eliminate the impact of central accumulation.

[0051] The method of this invention is applicable to blast furnaces using vanadium-titanium magnetite as the main feedstock. During normal production, the TiO2 content of the blast furnace slag is ≥20%. The main feedstocks used are vanadium-titanium sinter, vanadium-titanium pellets, and a small amount of ordinary lump ore. Specifically, the TiO2 content in the vanadium-titanium sinter is ≥3.0%, and the proportion of vanadium-titanium sinter in the furnace feed is between 40% and 90%. The TiO2 content in the vanadium-titanium pellets is ≥8.0%, and the proportion of vanadium-titanium pellets in the furnace feed is between 10% and 60%. The blast furnace must be in normal production, and the average blast volume must be between 95% and 100% of normal operating volume.

[0052] In the blast furnace smelting process of high-titanium vanadium-titanium magnetite, slight accumulation often occurs in the central area of ​​the blast furnace hearth due to adverse changes in the quality of raw materials and fuels, deformation of the tuyeres such as varying degrees of upturning, and other reasons that cause shutdowns and restarts after normal production resumes. When indicators such as the central airflow of the blast furnace and the central temperature of the blast furnace bottom are difficult to reflect, the method of this invention can be used to provide early warning and handle whether there is accumulation in the blast furnace hearth.

[0053] The method of the present invention continuously analyzes the chemical composition of the molten iron trough samples from each heat during the tapping process, mainly analyzing C, Ti and Si in the molten iron. The sampling point of the molten iron is kept at the same location, for example, the sampling point is fixed at the small well at the end of the main molten iron trough, and the sampling time is fixed between 20 min and 30 min during tapping. At the same time, the temperature is measured by a contact disposable thermocouple.

[0054] like Figure 1 As shown, this invention provides a method for early warning and handling of vanadium-titanium magnetite blast furnace hearth accumulation. The method involves the following steps during blast furnace tapping:

[0055] The first and second carbon contents in molten iron are detected. The first carbon content is compared with a threshold range, and the second carbon content is compared with a minimum threshold.

[0056] In response to the comparison results of the first carbon content with the threshold range and the comparison results of the second carbon content with the minimum threshold, the titanium content and silicon content in the molten iron are detected, and the average value of the difference between the titanium content and the silicon content is compared with the difference threshold.

[0057] Based on the above comparison results, determine whether there is hearth buildup.

[0058] In one embodiment of the present invention, detecting the first carbon content, the second carbon content, the titanium content, and the silicon content in molten iron includes the following steps: detecting the carbon content, titanium content, and silicon content in each of the M consecutive heats of molten iron from N groups, obtaining the average carbon content of the M heats of molten iron to obtain the first carbon content; obtaining the minimum carbon content of the M consecutive heats of molten iron from N groups to obtain the second carbon content; obtaining the difference between the titanium content and the silicon content in each of the M heats of molten iron, and then calculating the average value to obtain the average value of the difference between the titanium content and the silicon content.

[0059] In a preferred embodiment of the invention, the carbon, titanium, and silicon content of molten iron in each of three groups (i.e., N=3) of six consecutive heats (i.e., M=6) is detected. That is, a total of eighteen consecutive heats of molten iron are detected, divided into three groups of six consecutive heats. The average carbon content of the molten iron in each group of six consecutive heats is the first carbon content, and the minimum carbon content of the molten iron in the three groups of eighteen heats is the second carbon content. The difference between the titanium and silicon content in the molten iron of each of the six consecutive heats in each group is obtained. Then, the differences between the titanium and silicon content in each of the six heats are summed and averaged to obtain the average difference between the titanium and silicon content in each group. This invention continuously monitors the differences between the carbon, titanium, and silicon content in molten iron, and then, based on the changes in the average carbon content, the minimum carbon content, and the average difference between the titanium and silicon content, judges and handles the blast furnace hearth state based on the following judgment rules. The following is combined with... Figure 2 The present invention provides a detailed description of the early warning method for vanadium-titanium magnetite blast furnace hearth accumulation and how to treat the blast furnace hearth.

[0060] First, there is no buildup in the hearth if the following conditions are met: in N consecutive groups, the first carbon content is within the first threshold range, and the second carbon content is greater than or equal to the first minimum threshold.

[0061] In a preferred embodiment, the first threshold range is 4.50%-5.20%, and the first minimum threshold is 4.40%. That is, if 4.50% ≤ the first carbon content of three consecutive groups ≤ 5.20%, and the second carbon content ≥ 4.40%, the blast furnace condition is in a good state, and no measures need to be taken.

[0062] Second, if the following conditions are met, there is no accumulation in the hearth: in N consecutive groups, the first carbon content is within the second threshold range, and the second carbon content is greater than or equal to the second minimum threshold.

[0063] In a preferred embodiment, the second threshold range is 4.20%-4.50%, and the second minimum threshold is 4.10%. That is, if 4.20% ≤ the first carbon content of three consecutive groups ≤ 4.50%, and the second carbon content ≥ 4.10%, the blast furnace condition is still generally normal.

[0064] Furthermore, in a furnace hearth without buildup, if the average difference between the titanium content and the silicon content is greater than or equal to a first difference threshold, preferably 0.03%, that is, when [Ti-Si]... 均 If the concentration is ≥0.03%, no action needs to be taken on the hearth.

[0065] Furthermore, in a furnace hearth without buildup, if the average difference between the titanium content and the silicon content is less than a first difference threshold, i.e., when [Ti-Si]... 均 If the concentration is less than 0.03%, then the first measure for the hearth needs to be taken. The first measure includes: increasing the strength of the raw materials fed into the furnace (including the strength of the sintering drum, the compressive strength of the pellets, the CSR of the coke, M40, and M10). If the strength of the raw materials fed into the furnace cannot be improved in the short term, then the coke load should be reduced by 3%.

[0066] Third, if the following conditions are met, a slight buildup in the hearth will trigger an alarm: in N consecutive groups, the first carbon content is within the third threshold range, and the second carbon content is greater than or equal to the third minimum threshold.

[0067] In a preferred embodiment, the third threshold range is 4.00%-4.20%, and the third minimum threshold is 3.90%. That is, if 4.00% ≤ the first carbon content of three consecutive groups ≤ 4.20%, and the second carbon content ≥ 3.90%, the blast furnace condition is in a state of reduced activity in the hearth center and slight accumulation, triggering an early warning state for furnace condition assessment.

[0068] In the case of slight accumulation in the furnace hearth, further, if the average difference between the titanium content and the silicon content is greater than or equal to a second difference threshold, preferably the second difference threshold is 0.00%, i.e., when [Ti-Si]... 均 If the concentration is ≥0.00%, a second measure needs to be taken for the hearth. This second measure includes: increasing the strength of the raw materials fed into the furnace (including sintering drum strength, pellet compressive strength, coke CSR, M40, and M10), and reducing the coke load by 3%. If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, and the ore batch weight will be reduced by 3%.

[0069] Furthermore, given a slight buildup in the furnace hearth, if the average difference between the titanium content and the silicon content is less than a second difference threshold, i.e., when [Ti-Si]... 均 When the concentration is <0.00%, a third measure needs to be taken for the hearth. This third measure includes: increasing the strength of the raw materials fed into the furnace (including sintering drum strength, pellet compressive strength, coke CSR, M40, and M10), reducing the coke load by 5%, reducing the ore batch weight by 5%, and simultaneously increasing the proportion of iron-manganese ore in the furnace charge structure by 2%, with MnO ≥ 10% in the iron-manganese ore. If the strength of the raw materials fed into the furnace cannot be improved in the short term, then the coke load should be reduced by 5%, the ore batch weight by 5%, and 3% iron-manganese ore should be added to the furnace charge structure. Those skilled in the art should understand that iron-manganese ore can not only inhibit the formation of titanium carbonitride but also oxidize and eliminate carbon deposition.

[0070] Fourth, if the following conditions are met, the furnace hearth will be severely clogged, triggering an early warning: the first carbon content in N consecutive groups is within the fourth threshold range.

[0071] In a preferred embodiment, the fourth threshold range is less than or equal to 4.00%. That is, if the first carbon content of three consecutive groups is ≤4.00%, the blast furnace condition is in a state of reduced activity in the hearth center and increased accumulation in the center.

[0072] In a state of severe buildup in the furnace hearth, further, if the average difference between the titanium content and the silicon content is greater than or equal to a second difference threshold, i.e., when [Ti-Si]... 均 When the concentration is ≥0.00%, a fourth measure needs to be taken for the hearth. This fourth measure includes: increasing the strength of the raw materials fed into the furnace (including sintering drum strength, pellet compressive strength, coke CSR, M40, and M10), reducing the coke load by 5%, reducing the ore batch weight by 5%, and adding 3% iron-manganese ore to the furnace charge structure. If the strength of the raw materials fed into the furnace cannot be improved in the short term, then the coke load should be reduced by 5%, the ore batch weight by 5%, and 3% iron-manganese ore and 2% fluorite should be added to the furnace charge structure.

[0073] In a state of severe buildup in the furnace hearth, further, if the average difference between the titanium content and the silicon content is less than a second difference threshold, i.e., when [Ti-Si]... 均 If the concentration is less than 0.00%, a fifth measure must be taken for the hearth. This fifth measure includes: increasing the intensity of the raw materials fed into the furnace (including sintering drum strength, pellet compressive strength, coke CSR, M40, and M10), reducing the coke load by 5%, reducing the ore batch weight by 5%, and simultaneously increasing the furnace charge structure by 3% of the feed weight of iron-manganese ore and 2% of fluorite. If the intensity of the raw materials fed into the furnace cannot be improved in the short term, then the coke load should be reduced by 5%, the ore batch weight by 5%, and the furnace charge structure should simultaneously increase the feed weight of iron-manganese ore by 3% of the feed weight of fluorite.

[0074] Under the above judgment rules, when the hearth is judged to be inactive, the working condition of the blast furnace hearth can be improved by continuously smelting for 1 to 2 days through the above-mentioned operation and treatment. Furthermore, the addition of manganese ore and fluorite is preferably carried out by adding coke to the furnace through a center coking method.

[0075] The method of this invention is applied to blast furnace A, which uses high-titanium vanadium-titanium magnetite as the main raw material. During normal production, the average TiO2 content in the slag is 22.3%, and the blast furnace utilization coefficient is between 2.50 t / (m³). 3 ·d)~2.80t / (m 3Between ·d), the ore batch weight ranged from 27 to 28 t / batch, and the coke load ranged from 4.50 to 4.75 t / t. Affected by changes in the quality and structure of coking coal, the coke CSR slowly decreased by 3 percentage points within a week. However, from the perspective of blast furnace conditions, the average blast volume and output indicators did not change significantly, and the increase in blast pressure was not significant under the same blast volume. However, from the analysis and statistics of hot iron trough samples, the primary carbon content in the hot iron gradually decreased from an average of 4.48% to 4.12%, and the [Ti-Si] content in the hot iron... 均 The value decreased from 0.06% to 0.01%, occasionally falling below 0.00%. It was determined that the prolonged decrease in coke thermal strength (CSR) led to slight accumulation in the center of the hearth. Since increasing the proportion of high-quality coking coal could not improve coke thermal strength in the short term, to prevent further accumulation in the blast furnace center, a 5% reduction in coke load and 5% in ore batch weight was implemented. Simultaneously, the burden structure was modified by increasing the specific gravity of iron-manganese ore by 3% to improve the overall permeability of the blast furnace burden, increase the MnO content in the slag, and improve the oxygen potential and fluidity of the slag. After smelting under these conditions for two days, the first statistical value of carbon content in the molten iron rebounded and stabilized at around 4.4%, and the [Ti-Si] content in the molten iron... 均 The value rebounded and stabilized at around 0.04%. During this period, the first carbon content in the molten iron showed three consecutive values ​​as high as 4.8%, indicating that the graphite carbon deposited in the center of the hearth was effectively removed under the effect of this method. After the furnace conditions returned to normal and smelting continued for another day, the ore batch weight and coke load were gradually increased, and the iron-manganese ore was removed. Subsequently, with the increase in the amount and proportion of high-quality coking coal, the coke quality improved, and the furnace conditions achieved long-term stable operation.

[0076] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0077] The terms "comprising" and "having," and any variations thereof, used in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion; the terms "first," "second," etc., used in the specification, claims, and accompanying drawings are used to distinguish different objects, not to describe a particular order. "A plurality of" means two or more, unless otherwise explicitly specified.

[0078] It should be noted that the components or steps in the above embodiments can be interchanged, substituted, added, or deleted. Therefore, the combinations formed by these reasonable permutations and transformations should also fall within the protection scope of this invention, and the protection scope of this invention should not be limited to the above embodiments.

[0079] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of the different aspects of the invention as described above exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A method for early warning and handling of vanadium-titanium magnetite ore buildup in the hearth of a blast furnace, characterized in that, When tapping iron from the blast furnace, perform the following steps: The first and second carbon contents in molten iron are detected. The first carbon content is compared with a threshold range, and the second carbon content is compared with a minimum threshold. In response to the comparison results of the first carbon content with the threshold range and the comparison results of the second carbon content with the minimum threshold, the titanium content and silicon content in the molten iron are detected, and the average value of the difference between the titanium content and the silicon content is compared with the difference threshold. Based on the above comparison results, determine whether hearth buildup has occurred; among which... The determination of the primary carbon content, secondary carbon content, titanium content, and silicon content in molten iron includes the following steps: The carbon, titanium, and silicon content of molten iron in each of M consecutive heats from N groups was measured: Obtain the average carbon content in the molten iron from M heats to get the first carbon content; Obtain the minimum carbon content in M ​​consecutive batches of molten iron from N groups to obtain the second carbon content; Obtain the difference between titanium and silicon content in the molten iron for each of the M heats, then calculate the average value to obtain the average difference between titanium and silicon content; where, (1) No buildup will occur in the hearth if the following conditions are met: In N consecutive groups, the first carbon content is within a first threshold range, and the second carbon content is greater than or equal to a first minimum threshold, the first threshold range being 4.50%-5.20%; (2) No buildup will occur in the hearth if the following conditions are met: In N consecutive groups, the first carbon content is within the second threshold range, and the second carbon content is greater than or equal to the second minimum threshold, with the second threshold range being 4.20%-4.50%. (3) If the following conditions are met, slight buildup in the furnace hearth will trigger an alarm: In N consecutive groups, the first carbon content is within the third threshold range, and the second carbon content is greater than or equal to the third minimum threshold. The third threshold range is 4.00%-4.20%. (4) If the following conditions are met, severe accumulation in the hearth will trigger an early warning: In N consecutive groups, the first carbon content is within the fourth threshold range, which is less than or equal to 4.00%.

2. The method according to claim 1, characterized in that, There will be no buildup in the hearth if the following conditions are met: In N consecutive groups, the first carbon content is within the second threshold range, and the second carbon content is greater than or equal to the second minimum threshold. If the average difference between the titanium content and the silicon content is greater than or equal to the first difference threshold, then no measures need to be taken for the furnace hearth. If the average difference between the titanium content and the silicon content is less than the first difference threshold, then the first measure needs to be taken for the furnace hearth: Increase the intensity of raw materials entering the furnace; If the intensity of raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 3%.

3. The method according to claim 1, characterized in that, If the following conditions are met, a slight buildup in the furnace hearth will trigger an alert: In N consecutive groups, the first carbon content is within the third threshold range, and the second carbon content is greater than or equal to the third minimum threshold. If the average difference between the titanium content and the silicon content is greater than or equal to the second difference threshold, then a second measure needs to be taken for the furnace hearth: Increasing the intensity of raw materials fed into the furnace reduces coke load by 3%; If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5% and the ore batch weight by 3%. If the average difference between the titanium content and the silicon content is less than the second difference threshold, then a third measure needs to be taken for the furnace hearth: Increase the intensity of raw materials and fuels fed into the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase the proportion of iron-manganese ore in the furnace charge structure by 2%, with MnO ≥ 10% in the iron-manganese ore; If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and the proportion of iron-manganese ore fed into the furnace will be increased by 3% in the furnace charge structure.

4. The method according to claim 1, characterized in that, If the following conditions are met, severe buildup in the furnace hearth will trigger an early warning: In N consecutive groups, the first carbon content falls within the fourth threshold range. If the average difference between the titanium content and the silicon content is greater than or equal to the second difference threshold, then a fourth measure needs to be taken for the furnace hearth: Increase the intensity of raw materials and fuels fed into the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase the proportion of iron-manganese ore fed into the furnace burden by 3% in the furnace structure. If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and the furnace charge structure will be increased by 3% of the proportion of iron-manganese ore and 2% of fluorite. If the average difference between the titanium content and the silicon content is less than the second difference threshold, then a fifth measure needs to be taken for the furnace hearth: Increase the intensity of raw materials fed into the furnace, reduce coke load by 5%, reduce ore batch weight by 5%, and increase the proportion of iron-manganese ore and fluorite in the furnace charge structure by 3%; If the strength of the raw materials fed into the furnace cannot be improved in the short term, the coke load will be reduced by 5%, the ore batch weight will be reduced by 5%, and the furnace charge structure will be increased by 3% for iron-manganese ore and 3% for fluorite.

5. The method according to claim 1, characterized in that, The sampling point for molten iron is kept at the same location, and sampling is carried out 20 to 30 minutes after tapping.

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