The Shanghai Meishan Iron and Steel Co., Ltd. has a large supply of coke oven gas (COG) and has the potential to develop and apply the spraying of COG on the surface of a sinter bed. The effects of the amount of COG, ...The Shanghai Meishan Iron and Steel Co., Ltd. has a large supply of coke oven gas (COG) and has the potential to develop and apply the spraying of COG on the surface of a sinter bed. The effects of the amount of COG, the spraying time, and the spraying distribution with the process on the quantity and quality indexes of sinter were investigated in the laboratory experi-ments. The results showed that the COG spraying can improve the sinter indexes to a large extent if appropriate parameters were used. It was found that an appropriate amount of COG, a relatively long spraying time, and a decreasing distribution of the COG amount with the spraying process all help to obtain a better performance for sinter quantity and quality indexes. When the COG spraying was applied to the No. 3 sintering machine, the sinter tumbler index increased by 0.45%, the overall finished product rate increased by 0.72%, the solid fuel consumption decreased by 4.06kg/t, the reducibility increased by 3.89%, and the cost of iron decreased by 5.29 CNY/t, and the CO2, SO2 and Nox emissions also decreased, thus proving the feasibility of this technology. Therefore, COG spraying provides a new way to improve sinter and also decrease the energy consumption and pollution.展开更多
Abnormal mold level fluctuation is frequently observed in high-speed casting,especially for peritectic steels,which has been shown to severely deteriorate product quality.Both an online electromagnetic sensor and an i...Abnormal mold level fluctuation is frequently observed in high-speed casting,especially for peritectic steels,which has been shown to severely deteriorate product quality.Both an online electromagnetic sensor and an ibaAnalyzer are used to analyze the frequency and amplitude of massive mold level fluctuation data from the slab casting process of different steel grades using different casting speeds,slab widths and physical parameters of mold flux.The results show that in the slab continuous casting process of peritectic steels,the main frequency and equivalent amplitude of abnormal mold level fluctuations first increase and then decrease with increasing the carbon content.In the production of various grades of steel,the main frequency of abnormal mold level fluctuation and the equivalent amplitude increase with increasing the casting speed,while the main frequency of abnormal mold level fluctuation changes little with increasing the casting width.The main frequency of abnormal mold level fluctuation is positively related to the surface tension of the mold flux.Based on these results,a new mechanism has been presented.It is shown that the abnormal mold level fluctuation is mainly induced by shell bulging while moving through the rollers,and resonance occurs when the frequency approaches the natural frequency of the molten steel in mold,which results in a large amplitude of the abnormal mold level fluctuation.Based on this mechanism,a new equation for the resonance frequency of molten steel is proposed.The improved method based on this mechanism has proved to be effective in controlling abnormal mold fluctuations.展开更多
The velocity distribution of sinter and gas in vertical cooling furnace(VCF)has an important influence on gas-solid heat transfer.Based on the slot model of single hopper in the VCF of Meishan Iron and Steel Co.,Ltd.,...The velocity distribution of sinter and gas in vertical cooling furnace(VCF)has an important influence on gas-solid heat transfer.Based on the slot model of single hopper in the VCF of Meishan Iron and Steel Co.,Ltd.,the velocity and particle size distribution of sinter and the velocity and pressure distribution of gas were studied using a computational fluid dynamics-discrete element method model to obtain the gas-solid flow rule in the VCF.The results showed that the velocity of sinter near the wall and the edge of vent cowl was lower than that in the rest of the same plane.Therefore,the rectangular section of the vertical cooling furnace can be divided into a quasi-static zone,a plug flow zone and a convergent flow zone according to the flow velocity of the sinter.The average particle size and the void fraction of sinter bed were distributed in"W"and"V"shape along the width direction,respectively.The distribution of gas velocity in the furnace cavity was uneven,and the high-velocity area gradually changed from the center to the edge of the furnace cavity with the rise of gas.Reducing the ratio of edge to center gas flow from 2.7∶1 to 0.7∶1 could improve the gas velocity,but could not change the gas velocity distribution.The gas velocity distribution was more affected by the average particle size distribution of the sinter bed.It was suggested that measures need be taken to adjust it to improve the gas velocity distribution in the VCF.展开更多
Since the current slagging of argon blowing refining process is relatively fixed,which cannot adapt to the fluctuation of converter smelting process,it poses the problems of poor metallurgical property of refining sla...Since the current slagging of argon blowing refining process is relatively fixed,which cannot adapt to the fluctuation of converter smelting process,it poses the problems of poor metallurgical property of refining slag and a large amount of molten heel.An optimization system coupled with multiple models was proposed to dynamic control the ladle slagging in the argon blowing refining process.It can compile the optimal dynamic slagging scheme in real time under the guarantee of deoxidation performance and reasonable fluidity.The argon blowing refining slag composition range of CaO/Al_(2)O_(3)=1.3-1.7,CaO/SiO_(2)=6-12,w(MgO)=2%-6% was determined based on FeO activity and liquidus temperature by equilibrium thermodynamic calculation.In addition,it demonstrated better performance in the viscosity prediction task of the presented Visual Geometry Group 16-like one-dimensional convolutional neural network deep learning algorithm versus the Random Forest ensemble learning algorithm,as the adjusted coefficients of determination were 0.9712 and 0.9637,respectively.After the system was applied in operation,the argon blowing refining process was stable,and the steel yield was enhanced,which promoted the intelligent steelmaking level while achieving the cost reduction and efficiency improvement.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Number 51804027)Fundamental Research Funds for the Central Universities(FRF-IC-18-010).
文摘The Shanghai Meishan Iron and Steel Co., Ltd. has a large supply of coke oven gas (COG) and has the potential to develop and apply the spraying of COG on the surface of a sinter bed. The effects of the amount of COG, the spraying time, and the spraying distribution with the process on the quantity and quality indexes of sinter were investigated in the laboratory experi-ments. The results showed that the COG spraying can improve the sinter indexes to a large extent if appropriate parameters were used. It was found that an appropriate amount of COG, a relatively long spraying time, and a decreasing distribution of the COG amount with the spraying process all help to obtain a better performance for sinter quantity and quality indexes. When the COG spraying was applied to the No. 3 sintering machine, the sinter tumbler index increased by 0.45%, the overall finished product rate increased by 0.72%, the solid fuel consumption decreased by 4.06kg/t, the reducibility increased by 3.89%, and the cost of iron decreased by 5.29 CNY/t, and the CO2, SO2 and Nox emissions also decreased, thus proving the feasibility of this technology. Therefore, COG spraying provides a new way to improve sinter and also decrease the energy consumption and pollution.
基金National Natural Science Foundation of China(No.U1560207)Special thanks are given to Shanghai Meishan Iron and Steel Co.,Ltd.for industrial trials and application.
文摘Abnormal mold level fluctuation is frequently observed in high-speed casting,especially for peritectic steels,which has been shown to severely deteriorate product quality.Both an online electromagnetic sensor and an ibaAnalyzer are used to analyze the frequency and amplitude of massive mold level fluctuation data from the slab casting process of different steel grades using different casting speeds,slab widths and physical parameters of mold flux.The results show that in the slab continuous casting process of peritectic steels,the main frequency and equivalent amplitude of abnormal mold level fluctuations first increase and then decrease with increasing the carbon content.In the production of various grades of steel,the main frequency of abnormal mold level fluctuation and the equivalent amplitude increase with increasing the casting speed,while the main frequency of abnormal mold level fluctuation changes little with increasing the casting width.The main frequency of abnormal mold level fluctuation is positively related to the surface tension of the mold flux.Based on these results,a new mechanism has been presented.It is shown that the abnormal mold level fluctuation is mainly induced by shell bulging while moving through the rollers,and resonance occurs when the frequency approaches the natural frequency of the molten steel in mold,which results in a large amplitude of the abnormal mold level fluctuation.Based on this mechanism,a new equation for the resonance frequency of molten steel is proposed.The improved method based on this mechanism has proved to be effective in controlling abnormal mold fluctuations.
基金Financial support provided by the Fundamental Research Funds for the Central Universities of China(N2225022)is gratefully acknowledged.
文摘The velocity distribution of sinter and gas in vertical cooling furnace(VCF)has an important influence on gas-solid heat transfer.Based on the slot model of single hopper in the VCF of Meishan Iron and Steel Co.,Ltd.,the velocity and particle size distribution of sinter and the velocity and pressure distribution of gas were studied using a computational fluid dynamics-discrete element method model to obtain the gas-solid flow rule in the VCF.The results showed that the velocity of sinter near the wall and the edge of vent cowl was lower than that in the rest of the same plane.Therefore,the rectangular section of the vertical cooling furnace can be divided into a quasi-static zone,a plug flow zone and a convergent flow zone according to the flow velocity of the sinter.The average particle size and the void fraction of sinter bed were distributed in"W"and"V"shape along the width direction,respectively.The distribution of gas velocity in the furnace cavity was uneven,and the high-velocity area gradually changed from the center to the edge of the furnace cavity with the rise of gas.Reducing the ratio of edge to center gas flow from 2.7∶1 to 0.7∶1 could improve the gas velocity,but could not change the gas velocity distribution.The gas velocity distribution was more affected by the average particle size distribution of the sinter bed.It was suggested that measures need be taken to adjust it to improve the gas velocity distribution in the VCF.
基金the fund support from the Natural Science Foundation of Anhui Provincial Education Department(KJ2021A0358)the National Natural Science Foundation of China(51804004).
文摘Since the current slagging of argon blowing refining process is relatively fixed,which cannot adapt to the fluctuation of converter smelting process,it poses the problems of poor metallurgical property of refining slag and a large amount of molten heel.An optimization system coupled with multiple models was proposed to dynamic control the ladle slagging in the argon blowing refining process.It can compile the optimal dynamic slagging scheme in real time under the guarantee of deoxidation performance and reasonable fluidity.The argon blowing refining slag composition range of CaO/Al_(2)O_(3)=1.3-1.7,CaO/SiO_(2)=6-12,w(MgO)=2%-6% was determined based on FeO activity and liquidus temperature by equilibrium thermodynamic calculation.In addition,it demonstrated better performance in the viscosity prediction task of the presented Visual Geometry Group 16-like one-dimensional convolutional neural network deep learning algorithm versus the Random Forest ensemble learning algorithm,as the adjusted coefficients of determination were 0.9712 and 0.9637,respectively.After the system was applied in operation,the argon blowing refining process was stable,and the steel yield was enhanced,which promoted the intelligent steelmaking level while achieving the cost reduction and efficiency improvement.