A blast furnace operation adjusting method based on silicon content of blast furnace molten iron

Abstract

The application discloses a kind of based on blast furnace molten iron silicon content blast furnace operation adjustment method, comprising the following steps: (1) in combination with the raw material condition of blast furnace, smelting load and the demand of subsequent steelmaking process, set blast furnace molten iron silicon content target interval and molten iron temperature target interval;(2) according to blast furnace tapping furnace, real-time acquisition every tapping molten iron silicon content detection value and molten iron temperature detection value, and after every complete 2 times tapping, the average silicon content of molten iron and the average temperature of molten iron of continuous 2 times tapping are calculated, as the judgment basis of blast furnace operation adjustment;(3) according to the average silicon content of molten iron and the average temperature of molten iron of continuous 2 times tapping, condition interval is divided and corresponding blast furnace operation adjustment strategy is executed;(4) after every complete 2 times blast furnace tapping, repeat execution step (2) and (3), continuously carry out dynamic adjustment to blast furnace operation, realize the closed loop stable control of molten iron silicon content.The application realizes the accurate closed loop control of blast furnace molten iron silicon content.

Description

Technical Field

[0001] This invention relates to the field of blast furnace ironmaking technology, and specifically to a blast furnace operation adjustment method based on the silicon content of molten iron. Background Technology

[0002] Blast furnace ironmaking is the core process in steel production, and the silicon content of molten iron is a key indicator for measuring the blast furnace's smelting condition, the quality of the molten iron, and the cost of subsequent steelmaking processes. If the silicon content of the molten iron is too high, it will increase the consumption of deoxidizers and smelting time in subsequent steelmaking processes, thus increasing production costs. If the silicon content of the molten iron is too low, it will lead to poor molten iron fluidity and insufficient heat in the hearth, thereby causing problems such as fluctuations in blast furnace conditions and difficulties in tapping iron. In severe cases, it may even cause major production accidents such as blast furnace bridging and shutdown.

[0003] Currently, the control of silicon content in blast furnace hot metal in the industry mainly relies on the manual experience of operators. Operators adjust parameters such as fuel ratio, blast volume, and oxygen-carbon ratio based on data from pre-furnace monitoring of silicon content and temperature, combined with their own operational experience. However, the following problems are prevalent: 1) Blast furnace smelting is a complex process with a large time lag and nonlinearity. Manual operation often only makes adjustments after the silicon content in the hot metal has significantly exceeded the target range, making it impossible to predict and precisely control in advance, resulting in large fluctuations and poor stability in silicon content; 2) It mainly relies on qualitative experience guidance, lacking standardized and quantifiable adjustment rules. Different operators have vastly different adjustment ranges and timings, easily leading to over-adjustment or under-adjustment, causing fluctuations in blast furnace conditions; 3) Focusing only on the single indicator of silicon content in hot metal without linking hot metal temperature and silicon content analysis makes it impossible to distinguish complex operating conditions such as low-temperature high-silicon and high-temperature low-silicon conditions, easily leading to misoperation. For example, blindly heating in low-temperature high-silicon conditions can further increase the silicon content, exacerbating furnace condition fluctuations.

[0004] Therefore, how to develop a standardized, quantifiable, and practical method for adjusting blast furnace operation to achieve precise and stable control of silicon content in molten iron has become an urgent problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a blast furnace operation adjustment method based on the silicon content of molten iron. The method uses the linkage data between the silicon content and the temperature of molten iron as the core judgment basis, establishes clear benchmark parameters, standardized operating condition division rules and gradient quantitative adjustment strategies. Through the standardization and quantitative control of blast furnace operation, it achieves precise closed-loop control of the silicon content of molten iron, completely eliminates the dependence on manual experience, greatly improves the consistency of operation among different operators, and effectively avoids the problems of over-adjustment or under-adjustment.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a blast furnace operation adjustment method based on the silicon content of molten iron, the innovation of which lies in including the following steps: (1) Based on the raw material conditions, smelting load and subsequent steelmaking process requirements of the blast furnace, set the target range for silicon content and the target range for molten iron temperature in the blast furnace. (2) Collect the silicon content and temperature of the molten iron in real time for each batch of blast furnace tapping. After each two batches of tapping, calculate the average silicon content and average temperature of the molten iron for the two consecutive batches as the basis for judging the adjustment of blast furnace operation. (3) Based on the average silicon content and average temperature of the molten iron obtained from the above two consecutive tappings, divide the operating conditions into intervals and implement the corresponding blast furnace operation adjustment strategies. (4) After each blast furnace tapping is completed twice, steps (2) and (3) are repeated to continuously adjust the blast furnace operation and achieve closed-loop stable control of the silicon content in the molten iron.

[0007] Preferably, in step (1) above, the target range for silicon content in blast furnace hot metal is set to 0.3~0.45%, and the target range for hot metal temperature is set to 1500℃~1530℃.

[0008] Preferably, in step (2) above, the detection values ​​of silicon content and temperature of molten iron are both obtained from online real-time detection data in the molten iron trough during the blast furnace tapping process, or from rapid detection data in the furnace front laboratory. The data acquisition delay time is no more than 10 minutes to ensure the real-time nature of the data and the timeliness of the adjustment.

[0009] Preferably, the blast furnace taps iron 12 times a day. After each batch of iron is tapped, the silicon content and temperature of the molten iron are collected in real time by an online component analyzer and temperature sensor in the molten iron trough. The data acquisition lag time is controlled within 5 minutes.

[0010] Preferably, in step (3) above, dividing the operating condition range and implementing the corresponding blast furnace operation adjustment strategy specifically involves: (3.1) When the average temperature of the molten iron tapped twice consecutively is ≤1500℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a low temperature and low silicon condition, and blast furnace heating operation shall be performed at this time. (3.2) When the average temperature of the molten iron tapped in two consecutive taps is ≤1500℃ and the average silicon content of the molten iron tapped in two consecutive taps is ≥0.45%, it is determined to be a low temperature and high silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out. (3.3) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≥0.45%, it is determined to be a high temperature and high silicon condition, and the blast furnace deheating operation shall be performed at this time. (3.4) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a high temperature and low silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out.

[0011] Preferably, in step (3.1) above, the blast furnace heating operation employs a gradient heating adjustment strategy based on different ranges of the average temperature of the molten iron, specifically as follows: (3.1.1) When the average temperature of the molten iron from two consecutive taps is 1480~1500℃ and the average silicon content of the molten iron from two consecutive taps is 0.3~0.4%, the first gradient heating operation is performed, that is, the blast furnace fuel ratio is increased by 5kg / t. (3.1.2) When the average temperature of the molten iron from two consecutive taps is 1460~1480℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the second-gradient heating operation is performed, that is, a batch of clean coke is added to the blast furnace, and the blast furnace fuel ratio is increased by 15kg / t and the blast furnace oxygen-carbon ratio O / C is decreased by 0.08. (3.1.3) When the average temperature of the molten iron from two consecutive taps is <1460℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the third-gradient heating operation is performed, that is, two batches of clean coke are added to the blast furnace, the blast furnace fuel ratio is increased by 25kg / t, and the blast furnace oxygen-carbon ratio (O / C) is decreased by 0.16.

[0012] Preferably, in step (3.3) above, the blast furnace deheating operation is based on a gradient deheating adjustment strategy according to different ranges of average iron temperature and average silicon content, specifically as follows: (3.3.1) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron from two consecutive taps is 0.45~0.5%, the first-gradient heat reduction operation shall be implemented, that is, the blast furnace fuel ratio shall be reduced by 5kg / t. (3.3.2) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron is >0.5%, the second-gradient heat reduction operation is performed, that is, the blast furnace fuel ratio is reduced by 10~15kg / t, and after 3 hours of continuous operation, the fuel ratio is then adjusted back by 5kg / t.

[0013] Preferably, the specific steps of the hot metal silicon content trend observation operation are as follows: continuously monitor the changes in hot metal silicon content and hot metal temperature after each subsequent tapping; if the average silicon content of hot metal after two consecutive tappings still exceeds the target range, and the average hot metal temperature fluctuates in the same direction, then switch to the corresponding blast furnace heating operation or blast furnace deheating operation; if the average silicon content of hot metal gradually returns to the target range, then maintain the current blast furnace operating parameters unchanged.

[0014] Preferably, in step (3) above, when the average temperature of the molten iron from two consecutive taps is within 1500~1515℃ and the average silicon content of the molten iron is within 0.3~0.45%, the current blast furnace operating parameters are kept unchanged, and the changes in the silicon content and temperature of the molten iron are continuously monitored.

[0015] The beneficial effects of this invention are: (1) This invention takes the linkage data of molten iron silicon content and molten iron temperature as the core judgment basis, establishes clear benchmark parameters, standardized working condition division rules and gradient quantitative adjustment strategies, and achieves precise closed-loop control of molten iron silicon content through the standardization and quantitative control of blast furnace operation, completely getting rid of the dependence on manual experience, greatly improving the consistency of operation of different operators, and effectively avoiding the problems of over-adjustment or under-adjustment. (2) This invention uses the average data of two consecutive tappings as the basis for judgment, which can effectively filter the occasional data fluctuations of a single furnace of molten iron. At the same time, through the precise division of the four working condition ranges, it greatly improves the control accuracy and stability of the silicon content of molten iron, realizes the precise matching of different smelting states, can predict the trend of furnace condition changes in advance, and can make adjustments in advance, which greatly reduces the fluctuation range of silicon content of molten iron. It can stably control the silicon content of molten iron within the target range of 0.3~0.45%, and significantly improve the stability of molten iron quality. (3) This invention performs a linkage analysis of molten iron temperature and molten iron silicon content, which can accurately distinguish complex working conditions such as low temperature and high silicon, high temperature and low silicon, and avoid the misoperation caused by focusing only on the single indicator of silicon content in traditional methods. At the same time, through a gradient small adjustment strategy, it avoids the drastic fluctuation of furnace conditions caused by large parameter adjustments, effectively ensuring the long-term smooth operation and stability of the blast furnace and reducing the blast furnace failure rate. (4) This invention achieves precise control of blast furnace heat through precise heating / heating operations, effectively avoiding fuel waste caused by overheating. At the same time, the stable silicon content of molten iron significantly reduces the consumption of deoxidizer and smelting costs in subsequent steelmaking processes, resulting in significant comprehensive economic benefits. (5) This invention achieves continuous dynamic closed-loop control of silicon content in blast furnace hot metal by repeatedly performing data acquisition, working condition judgment and operation adjustment every two taps. It can continuously optimize and adjust strategies according to real-time changes in furnace conditions, adapt to the blast furnace production needs under different raw material conditions and smelting loads, and has strong applicability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a blast furnace operation adjustment method based on the silicon content of molten iron according to the present invention. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below through specific embodiments.

[0019] This invention provides a blast furnace operation adjustment method based on the silicon content of molten iron, such as... Figure 1 As shown, it includes the following steps: (1) Based on the raw material conditions, smelting load and subsequent steelmaking process requirements of the blast furnace, set the target range of silicon content and the target range of molten iron temperature.

[0020] The target range for silicon content in blast furnace hot metal is set at 0.3-0.45%, and the target range for hot metal temperature is set at 1500℃-1530℃.

[0021] (2) Collect the silicon content and temperature of the molten iron in real time for each batch of blast furnace tapping. After each two batches of tapping, calculate the average silicon content and average temperature of the molten iron for the two consecutive batches as the basis for judging the adjustment of blast furnace operation.

[0022] The silicon content and temperature of molten iron in this invention are both measured using real-time online data from the molten iron trough during the blast furnace tapping process, or rapid data from the furnace front laboratory. The data acquisition lag time is no more than 10 minutes to ensure the real-time nature of the data and the timeliness of adjustments.

[0023] If online real-time detection data from the molten iron trough is used, the blast furnace will tap iron 12 times a day. After each batch of iron is tapped, the silicon content and temperature of the molten iron will be collected in real time by the online composition analyzer and temperature sensor in the molten iron trough. The data acquisition lag time will be controlled within 5 minutes.

[0024] (3) Based on the average silicon content and average temperature of the molten iron obtained from the above two consecutive tappings, divide the operating conditions into intervals and implement the corresponding blast furnace operation adjustment strategies.

[0025] In the above steps, the specific steps for dividing the operating condition range and implementing the corresponding blast furnace operation adjustment strategy are as follows: (3.1) When the average temperature of the molten iron tapped twice consecutively is ≤1500℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a low temperature and low silicon condition, and blast furnace heating operation shall be performed at this time. The blast furnace heating operation employs a gradient heating adjustment strategy based on different ranges of average iron temperature, specifically: (3.1.1) When the average temperature of the molten iron from two consecutive taps is 1480~1500℃ and the average silicon content of the molten iron from two consecutive taps is 0.3~0.4%, the first gradient heating operation is performed, that is, the blast furnace fuel ratio is increased by 5kg / t. (3.1.2) When the average temperature of the molten iron from two consecutive taps is 1460~1480℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the second-gradient heating operation is performed, that is, a batch of clean coke is added to the blast furnace, and the blast furnace fuel ratio is increased by 15kg / t and the blast furnace oxygen-carbon ratio O / C is decreased by 0.08. (3.1.3) When the average temperature of the molten iron from two consecutive taps is <1460℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the third-gradient heating operation is performed, that is, two batches of clean coke are added to the blast furnace, the blast furnace fuel ratio is increased by 25kg / t, and the blast furnace oxygen-carbon ratio (O / C) is decreased by 0.16.

[0026] (3.2) When the average temperature of the molten iron tapped twice consecutively is ≤1500℃ and the average silicon content of the molten iron tapped twice consecutively is ≥0.45%, it is determined to be a low temperature and high silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out.

[0027] (3.3) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≥0.45%, it is determined to be a high temperature and high silicon condition, and the blast furnace deheating operation shall be performed at this time. Among them, the blast furnace deheating operation implements a gradient deheating adjustment strategy based on different ranges of average iron temperature and average silicon content, specifically as follows: (3.3.1) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron from two consecutive taps is 0.45~0.5%, the first-gradient heat reduction operation shall be implemented, that is, the blast furnace fuel ratio shall be reduced by 5kg / t. (3.3.2) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron is >0.5%, the second-gradient heat reduction operation is performed, that is, the blast furnace fuel ratio is reduced by 10~15kg / t, and after 3 hours of continuous operation, the fuel ratio is then adjusted back by 5kg / t.

[0028] (3.4) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a high temperature and low silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out.

[0029] The specific steps for observing the trend of silicon content in molten iron in this invention are as follows: continuously monitor the changes in silicon content and temperature of molten iron after each subsequent tapping. If the average silicon content of molten iron after two consecutive tappings still exceeds the target range, and the average temperature of molten iron fluctuates in the same direction, then switch to the corresponding blast furnace heating operation or blast furnace deheating operation. If the average silicon content of molten iron gradually returns to the target range, then maintain the current blast furnace operating parameters unchanged.

[0030] When the average temperature of the molten iron after two consecutive taps is within 1500~1515℃ and the average silicon content of the molten iron is within 0.3~0.45%, the present invention maintains the current blast furnace operating parameters unchanged and continuously monitors the changes in silicon content and temperature of the molten iron to avoid furnace condition fluctuations caused by excessive adjustments.

[0031] (4) After each blast furnace tapping is completed twice, steps (2) and (3) are repeated to continuously adjust the blast furnace operation and achieve closed-loop stable control of the silicon content in the molten iron.

[0032] Example Taking a field application on a 2200m³ blast furnace as an example, the present invention provides a blast furnace operation adjustment method based on the silicon content of molten iron, comprising the following steps: (1) Based on the raw material conditions, smelting load and subsequent steelmaking process requirements of the blast furnace, the target range of silicon content in blast furnace hot metal is set to 0.3~0.45%, and the target range of hot metal temperature is 1500℃~1530℃.

[0033] (2) The blast furnace taps iron 12 times a day. After each batch of iron is tapped, the silicon content and temperature of the molten iron are collected in real time by the online composition analyzer and temperature sensor in the molten iron trough. The data acquisition lag time is controlled within 5 minutes. After every 2 batches of iron are tapped, the average silicon content and average temperature of the molten iron from the 2 consecutive batches are calculated as the basis for judging the adjustment of blast furnace operation.

[0034] (3) Based on the average silicon content and average temperature of the molten iron obtained from the two consecutive tappings in the above steps, the operating condition range is divided and the corresponding blast furnace operation adjustment strategy is implemented, specifically as follows: (3.1) When the average temperature of the molten iron tapped twice in a row is 1472℃ and the average silicon content of the molten iron is 0.28%, it is determined to be a low temperature and low silicon condition. At this time, the second gradient heating operation is performed, that is, a batch of clean coke is added to the blast furnace, and the blast furnace fuel ratio is increased from 495kg / t to 510kg / t, and the blast furnace oxygen-carbon ratio O / C is decreased from 1.02 to 0.94. (3.2) When the average temperature of the molten iron after two consecutive taps is 1492℃ and the average silicon content of the molten iron is 0.48%, it is determined to be a low temperature and high silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, that is, the change of silicon content and temperature of the molten iron after each subsequent tap is continuously monitored. The average silicon content of the molten iron after the two subsequent taps is 0.46% and 0.43%, respectively, gradually returning to the target range. Therefore, the current blast furnace operating parameters are kept unchanged and no major adjustments are made. (3.3) When the average temperature of the molten iron tapped twice in a row is 1522℃ and the average silicon content of the molten iron is 0.52%, it is determined to be a high temperature and high silicon condition. At this time, the second gradient heat reduction operation is executed, that is, the blast furnace fuel ratio is reduced from 498kg / t to 485kg / t. After 3 hours of continuous operation, the fuel ratio is then adjusted back to 490kg / t. (3.4) When the average temperature of the molten iron after two consecutive taps is 1518℃ and the average silicon content of the molten iron is 0.28%, it is determined to be a high temperature and low silicon condition. At this time, the trend observation operation of the silicon content of molten iron is carried out, that is, the silicon content and temperature of the molten iron after each subsequent tap are continuously monitored. The average silicon content of the molten iron after the two subsequent taps is 0.44% and 0.45%, respectively, and the temperature gradually drops to below 1510℃. Therefore, the current blast furnace operating parameters are kept unchanged. (3.5) When the average temperature of the molten iron from two consecutive taps is within 1508℃ and the average silicon content of the molten iron is within 0.38%, both are within the target range. At this time, the current blast furnace operating parameters are kept unchanged, and the changes in silicon content and temperature of the molten iron are continuously monitored.

[0035] (4) After each blast furnace tapping is completed twice, steps (2) and (3) are repeated to continuously adjust the blast furnace operation and achieve closed-loop stable control of the silicon content in the molten iron.

[0036] The field application results of this embodiment show that after applying the method of this invention to the blast furnace, the fluctuation range of silicon content in molten iron was significantly narrowed from the original 0.2~0.8% to 0.3~0.45%, and the compliance rate of silicon content in molten iron increased from the original 72% to over 96%; the blast furnace fuel ratio decreased from the original 498kg / t to 492kg / t, and the fuel cost per ton of iron was reduced by about 12 yuan; the consumption of deoxidizer per ton of steel in subsequent steelmaking processes was reduced by about 1.8kg, and the production cost per ton of steel was reduced by about 15 yuan, resulting in significant comprehensive economic benefits; at the same time, the stability of the blast furnace condition was greatly improved, and there were no problems such as furnace condition fluctuations or iron tapping difficulties caused by large fluctuations in silicon content, thus achieving long-term smooth and stable production of the blast furnace.

[0037] The beneficial effects of this invention are: (1) This invention takes the linkage data of molten iron silicon content and molten iron temperature as the core judgment basis, establishes clear benchmark parameters, standardized working condition division rules and gradient quantitative adjustment strategies, and achieves precise closed-loop control of molten iron silicon content through the standardization and quantitative control of blast furnace operation, completely getting rid of the dependence on manual experience, greatly improving the consistency of operation of different operators, and effectively avoiding the problems of over-adjustment or under-adjustment. (2) This invention uses the average data of two consecutive tappings as the basis for judgment, which can effectively filter the occasional data fluctuations of a single furnace of molten iron. At the same time, through the precise division of the four working condition ranges, it greatly improves the control accuracy and stability of the silicon content of molten iron, realizes the precise matching of different smelting states, can predict the trend of furnace condition changes in advance, and can make adjustments in advance, which greatly reduces the fluctuation range of silicon content of molten iron. It can stably control the silicon content of molten iron within the target range of 0.3~0.45%, and significantly improve the stability of molten iron quality. (3) This invention performs a linkage analysis of molten iron temperature and molten iron silicon content, which can accurately distinguish complex working conditions such as low temperature and high silicon, high temperature and low silicon, and avoid the misoperation caused by focusing only on the single indicator of silicon content in traditional methods. At the same time, through a gradient small adjustment strategy, it avoids the drastic fluctuation of furnace conditions caused by large parameter adjustments, effectively ensuring the long-term smooth operation and stability of the blast furnace and reducing the blast furnace failure rate. (4) This invention achieves precise control of blast furnace heat through precise heating / heating operations, effectively avoiding fuel waste caused by overheating. At the same time, the stable silicon content of molten iron significantly reduces the consumption of deoxidizer and smelting costs in subsequent steelmaking processes, resulting in significant comprehensive economic benefits. (5) This invention achieves continuous dynamic closed-loop control of silicon content in blast furnace hot metal by repeatedly performing data acquisition, working condition judgment and operation adjustment every two taps. It can continuously optimize and adjust strategies according to real-time changes in furnace conditions, adapt to the blast furnace production needs under different raw material conditions and smelting loads, and has strong applicability.

[0038] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, all modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the protection scope of the present invention. The technical content for which protection is sought in the present invention has been fully described in the technical requirements.

Claims

1. A blast furnace operation adjustment method based on the silicon content of molten iron, characterized in that... Includes the following steps: (1) Based on the raw material conditions, smelting load and subsequent steelmaking process requirements of the blast furnace, set the target range for silicon content and the target range for molten iron temperature in the blast furnace. (2) Collect the silicon content and temperature of the molten iron in real time for each batch of blast furnace tapping. After each two batches of tapping, calculate the average silicon content and average temperature of the molten iron for the two consecutive batches as the basis for judging the adjustment of blast furnace operation. (3) Based on the average silicon content and average temperature of the molten iron obtained from the above two consecutive tappings, divide the operating conditions into intervals and implement the corresponding blast furnace operation adjustment strategies. (4) After each blast furnace tapping is completed twice, steps (2) and (3) are repeated to continuously adjust the blast furnace operation and achieve closed-loop stable control of the silicon content in the molten iron.

2. The blast furnace operation adjustment method based on the silicon content of molten iron according to claim 1, characterized in that: In step (1) above, the target range for silicon content in blast furnace hot metal is set to 0.3-0.45%, and the target range for hot metal temperature is set to 1500℃-1530℃.

3. The blast furnace operation adjustment method based on the silicon content of molten iron according to claim 1, characterized in that: In step (2) above, the detection values ​​of silicon content and temperature of molten iron are both obtained from online real-time detection data in the molten iron trough during the blast furnace tapping process, or from rapid detection data in the furnace front laboratory. The data acquisition delay time is no more than 10 minutes to ensure the real-time nature of the data and the timeliness of the adjustment.

4. The blast furnace operation adjustment method based on the silicon content of molten iron according to claim 3, characterized in that: The blast furnace taps iron 12 times a day. After each batch of iron is tapped, the silicon content and temperature of the molten iron are collected in real time by an online composition analyzer and temperature sensor in the molten iron trough. The data acquisition lag time is controlled within 5 minutes.

5. The blast furnace operation adjustment method based on the silicon content of molten iron according to claim 1, characterized in that: In step (3) above, the specific steps for dividing the operating condition range and implementing the corresponding blast furnace operation adjustment strategy are as follows: (3.1) When the average temperature of the molten iron tapped twice consecutively is ≤1500℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a low temperature and low silicon condition, and blast furnace heating operation shall be performed at this time. (3.2) When the average temperature of the molten iron tapped in two consecutive taps is ≤1500℃ and the average silicon content of the molten iron tapped in two consecutive taps is ≥0.45%, it is determined to be a low temperature and high silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out. (3.3) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≥0.45%, it is determined to be a high temperature and high silicon condition, and the blast furnace deheating operation shall be performed at this time. (3.4) When the average temperature of the molten iron tapped twice consecutively is ≥1515℃ and the average silicon content of the molten iron tapped twice consecutively is ≤0.3%, it is determined to be a high temperature and low silicon condition. At this time, the trend observation operation of the silicon content of the molten iron is carried out, and the large heating / heating adjustment is temporarily not carried out.

6. The blast furnace operation adjustment method based on the silicon content of molten iron according to claim 5, characterized in that: In step (3.1) above, the blast furnace heating operation is based on a gradient heating adjustment strategy according to different ranges of the average temperature of the molten iron, specifically as follows: (3.1.1) When the average temperature of the molten iron from two consecutive taps is 1480~1500℃ and the average silicon content of the molten iron from two consecutive taps is 0.3~0.4%, the first gradient heating operation is performed, that is, the blast furnace fuel ratio is increased by 5kg / t. (3.1.2) When the average temperature of the molten iron from two consecutive taps is 1460~1480℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the second-gradient heating operation is performed, that is, a batch of clean coke is added to the blast furnace, and the blast furnace fuel ratio is increased by 15kg / t and the blast furnace oxygen-carbon ratio O / C is decreased by 0.

08. (3.1.3) When the average temperature of the molten iron from two consecutive taps is <1460℃ and the average silicon content of the molten iron from two consecutive taps is <0.3%, the third-gradient heating operation is performed, that is, two batches of clean coke are added to the blast furnace, the blast furnace fuel ratio is increased by 25kg / t, and the blast furnace oxygen-carbon ratio (O / C) is decreased by 0.

16.

7. A blast furnace operation adjustment method based on the silicon content of molten iron according to claim 5, characterized in that: In step (3.3) above, the blast furnace deheating operation is based on a gradient deheating adjustment strategy according to different ranges of average iron temperature and average silicon content, specifically as follows: (3.3.1) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron from two consecutive taps is 0.45~0.5%, the first-gradient heat reduction operation shall be implemented, that is, the blast furnace fuel ratio shall be reduced by 5kg / t. (3.3.2) When the average temperature of the molten iron from two consecutive taps is ≥1515℃ and the average silicon content of the molten iron is >0.5%, the second-gradient heat reduction operation is performed, that is, the blast furnace fuel ratio is reduced by 10~15kg / t, and after 3 hours of continuous operation, the fuel ratio is then adjusted back by 5kg / t.

8. A blast furnace operation adjustment method based on the silicon content of molten iron according to claim 5, characterized in that: The specific steps for observing the trend of silicon content in molten iron are as follows: continuously monitor the changes in silicon content and temperature of molten iron after each subsequent tapping. If the average silicon content of molten iron after two consecutive tappings still exceeds the target range, and the average temperature of molten iron fluctuates in the same direction, then switch to the corresponding blast furnace heating operation or blast furnace deheating operation. If the average silicon content of molten iron gradually returns to the target range, then maintain the current blast furnace operating parameters unchanged.

9. A blast furnace operation adjustment method based on the silicon content of molten iron according to claim 1, characterized in that: In step (3) above, when the average temperature of the molten iron from two consecutive taps is within 1500~1515℃ and the average silicon content of the molten iron is within 0.3~0.45%, the current blast furnace operating parameters are kept unchanged, and the changes in silicon content and temperature of the molten iron are continuously monitored.

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