The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ...The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter.展开更多
The experiment was carried out in a combined blowing converter.The natural gas was supplied as the cooling medium for the bottom lance.The blow- ing practice of medium P hot metal (0.30-0.85% [P]) indicated that with ...The experiment was carried out in a combined blowing converter.The natural gas was supplied as the cooling medium for the bottom lance.The blow- ing practice of medium P hot metal (0.30-0.85% [P]) indicated that with better stirring at the bottom of the converter and lower P_(CO),this steelmgking process was favorable to reduce the amount of [C] and [O] and increase the (P_2O_5)/[P]. The maximum rate of dephospborization might be high up to 0.0a5%/min and the P content in steel could be reduced to lower than 0.03% by single slag-forming operation.展开更多
Bubble defect is one of the main defects of an automobile sheet.To solve this defect,the technology for nitrogen-argon mixed gas blowing on the tundish stopper is developed,the theoretical research on nitrogen absorpt...Bubble defect is one of the main defects of an automobile sheet.To solve this defect,the technology for nitrogen-argon mixed gas blowing on the tundish stopper is developed,the theoretical research on nitrogen absorption in the molten steel is performed,the nitrogen-argon mixed gas blowing equipment is developed and experimented in the plant.The expected effect is achieved in the industrial test,and the slab inclusion density and quality degradation ratio of the automobile sheet are significantly reduced.展开更多
The effects of operation parameters of combined blowing converter on the volumetric mass transfer coefficient between slag and steel are studied with a cold model with water simulating steel, oil simulating slag and b...The effects of operation parameters of combined blowing converter on the volumetric mass transfer coefficient between slag and steel are studied with a cold model with water simulating steel, oil simulating slag and benzoic acid as the transferred substance between water and oil. The results show that, with lance level of 2.1m and the top blowing rate of 25000Nm3/h, the volumetric mass transfer coefficient changes most significantly when the bottom blowing rate ranges from 384 to 540Nm3/h. The volumetric mass transfer coefficient reaches its maximum when the lance level is 2.1m, the top blowing rates is 30000Nm3/h, and the bottom blowing rate is 384Nm3/h with tuyeres located symmetrically at 0.66D of the converter bottom.展开更多
The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Fo...The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Four blowing conditions are considered in the computer runs: top blowing, combined blowing using just a bottom centered nozzle, combined blowing using two bottom lateral nozzles, and full combined blowing using the three top and the three bottom nozzles. Computer simulations show that full combined blowing provides greater slag splashing than conventional top blowing.展开更多
By measuring the volume concentration of SO<sub>2</sub> produced,blow rate of air（m<sup>3</sup>/min）Band converting times τ,the mathematical model of converting for oxidizing FeS and Cu<s...By measuring the volume concentration of SO<sub>2</sub> produced,blow rate of air（m<sup>3</sup>/min）Band converting times τ,the mathematical model of converting for oxidizing FeS and Cu<sub>2</sub>S,and that of controlling end point can be developed according to the slag making period andcopper making period,respectively.This derived model may be well suitable for either sideblow or top blow converter if the parameters-SO<sub>2</sub>B,τ.can be measured accurately.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos.51974023 and52374321)the funding of State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,China (No.41620007)。
文摘The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter.
文摘The experiment was carried out in a combined blowing converter.The natural gas was supplied as the cooling medium for the bottom lance.The blow- ing practice of medium P hot metal (0.30-0.85% [P]) indicated that with better stirring at the bottom of the converter and lower P_(CO),this steelmgking process was favorable to reduce the amount of [C] and [O] and increase the (P_2O_5)/[P]. The maximum rate of dephospborization might be high up to 0.0a5%/min and the P content in steel could be reduced to lower than 0.03% by single slag-forming operation.
文摘Bubble defect is one of the main defects of an automobile sheet.To solve this defect,the technology for nitrogen-argon mixed gas blowing on the tundish stopper is developed,the theoretical research on nitrogen absorption in the molten steel is performed,the nitrogen-argon mixed gas blowing equipment is developed and experimented in the plant.The expected effect is achieved in the industrial test,and the slab inclusion density and quality degradation ratio of the automobile sheet are significantly reduced.
文摘The effects of operation parameters of combined blowing converter on the volumetric mass transfer coefficient between slag and steel are studied with a cold model with water simulating steel, oil simulating slag and benzoic acid as the transferred substance between water and oil. The results show that, with lance level of 2.1m and the top blowing rate of 25000Nm3/h, the volumetric mass transfer coefficient changes most significantly when the bottom blowing rate ranges from 384 to 540Nm3/h. The volumetric mass transfer coefficient reaches its maximum when the lance level is 2.1m, the top blowing rates is 30000Nm3/h, and the bottom blowing rate is 384Nm3/h with tuyeres located symmetrically at 0.66D of the converter bottom.
文摘The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Four blowing conditions are considered in the computer runs: top blowing, combined blowing using just a bottom centered nozzle, combined blowing using two bottom lateral nozzles, and full combined blowing using the three top and the three bottom nozzles. Computer simulations show that full combined blowing provides greater slag splashing than conventional top blowing.
文摘By measuring the volume concentration of SO<sub>2</sub> produced,blow rate of air（m<sup>3</sup>/min）Band converting times τ,the mathematical model of converting for oxidizing FeS and Cu<sub>2</sub>S,and that of controlling end point can be developed according to the slag making period andcopper making period,respectively.This derived model may be well suitable for either sideblow or top blow converter if the parameters-SO<sub>2</sub>B,τ.can be measured accurately.
