The top-bottom combined blowing converter mainly adopts the blowing method of top-blowing oxygen and bottom-blowing nitrogen.In the production process,there are some disadvantages,such as a significant temperature dif...The top-bottom combined blowing converter mainly adopts the blowing method of top-blowing oxygen and bottom-blowing nitrogen.In the production process,there are some disadvantages,such as a significant temperature difference between the top and bottom of the molten pool,inadequate gas permeability of bottom blowing,and low decarburization efficiency.Therefore,we propose a novel bottom-blowing gas doped oxygen process to enhance the smelting conditions in the converter.The 500 kg medium frequency induction furnace with top and bottom-blowing function was used to explore the influence of the proportion of bottom-blowing gas doped oxygen on the smelting effect in different smelting cycles.Subsequently,industrial experimental verification was carried out on a 60 t converter.The results of intermediate frequency furnace experiments demonstrate that the bottom-blowing gas doped oxygen process exhibits a superior heating rate and decarburization efficiency during the initial and final stages of blowing compared to pure N2 used for bottom-blowing.Simultaneously,the dephosphorization efficiency exhibited an initial increase followed by a subsequent decrease as the bottom-blowing oxygen content increased.The industrial test of 60 t converter validates the findings above.Moreover,when the oxygen content in bottom-blowing gas is 5%,the average blowing time reduces by 54 s,and the minimum endpoint carbon-oxygen equilibrium reaches 0.00219 under this condition.The results demonstrate that the appropriate amount of oxygen doped in bottom-blowing gas can effectively enhance the metallurgical conditions of the converter and improve production efficiency.展开更多
Nowadays, in China, the bottom-blowing technique plays an important role in accelerating the molten bath stirring and promoting the metallurgical reactions in electric arc furnace (EAF) steelmaking. The innovations of...Nowadays, in China, the bottom-blowing technique plays an important role in accelerating the molten bath stirring and promoting the metallurgical reactions in electric arc furnace (EAF) steelmaking. The innovations of bottom-blowing technologies in EAF steelmaking were reviewed. The optimized bottom-blowing arrangement in EAF based on the furnace structure and the position of electrodes was introduced, and the fluid flow characteristics of EAF molten bath with bottomblowing were analyzed. Furthermore, bottom-blowing CO2 in EAF can facilitate the carbon-oxygen reaction reaching equilibrium and decrease the content of nitrogen in molten steel due to its special metallurgical properties. Pulsating bottom-blowing in EAF can effectively improve the molten bath stirring through the action of the unsteady bottom blowing gas streams, which could make the fluid flow field more disorderly than the steady bottom-blowing. And submerged O2 injection with CO2 in EAF can noticeably strengthen the EAF molten bath stirring, increase the production efficiency and improve the molten steel quality.展开更多
In bottom-blown copper smelting processes,oxygen-enriched air is typically injected into the melt through a lance,generating bubbles that ascend and agitate the melt,enhancing mass,momentum,and heat transfer within th...In bottom-blown copper smelting processes,oxygen-enriched air is typically injected into the melt through a lance,generating bubbles that ascend and agitate the melt,enhancing mass,momentum,and heat transfer within the furnace.The melt’s viscosity,which varies across reaction stages,and the operating conditions influence bubble size and dynamics.This study investigates the interplay between melt viscosity and bubble diameter on bubble motion using numerical simulations and experiments.In particular,the volume of fluid(VOF)method andΩ-identification technique were employed to analyze bubble velocity,deformation,trajectories,and wake characteristics.The results showed that bubble ascent velocity increases with bubble size and decreases in viscosity,though viscosity variations minimally affect the maximum velocity.Larger bubbles or those in less viscous melts exhibit greater deformation.Bubbles ascend primarily in straight trajectories with minor lateral oscillations regardless of viscosity.In terms of wake dynamics,vortex sizes grow as viscosity decreases,with bottom-formed vortices expanding significantly with increasing bubble size,while lateral vortices are less influenced.展开更多
In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research resu...In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.展开更多
基金supported by the National Natural Science Foundation of China(No.U21A20317)the National Key Research and Development Program of China(No.2017YFB0304201).
文摘The top-bottom combined blowing converter mainly adopts the blowing method of top-blowing oxygen and bottom-blowing nitrogen.In the production process,there are some disadvantages,such as a significant temperature difference between the top and bottom of the molten pool,inadequate gas permeability of bottom blowing,and low decarburization efficiency.Therefore,we propose a novel bottom-blowing gas doped oxygen process to enhance the smelting conditions in the converter.The 500 kg medium frequency induction furnace with top and bottom-blowing function was used to explore the influence of the proportion of bottom-blowing gas doped oxygen on the smelting effect in different smelting cycles.Subsequently,industrial experimental verification was carried out on a 60 t converter.The results of intermediate frequency furnace experiments demonstrate that the bottom-blowing gas doped oxygen process exhibits a superior heating rate and decarburization efficiency during the initial and final stages of blowing compared to pure N2 used for bottom-blowing.Simultaneously,the dephosphorization efficiency exhibited an initial increase followed by a subsequent decrease as the bottom-blowing oxygen content increased.The industrial test of 60 t converter validates the findings above.Moreover,when the oxygen content in bottom-blowing gas is 5%,the average blowing time reduces by 54 s,and the minimum endpoint carbon-oxygen equilibrium reaches 0.00219 under this condition.The results demonstrate that the appropriate amount of oxygen doped in bottom-blowing gas can effectively enhance the metallurgical conditions of the converter and improve production efficiency.
基金The authors would like to express their thanks for the support by the National Natural Science Foundation of China (No.51734003).
文摘Nowadays, in China, the bottom-blowing technique plays an important role in accelerating the molten bath stirring and promoting the metallurgical reactions in electric arc furnace (EAF) steelmaking. The innovations of bottom-blowing technologies in EAF steelmaking were reviewed. The optimized bottom-blowing arrangement in EAF based on the furnace structure and the position of electrodes was introduced, and the fluid flow characteristics of EAF molten bath with bottomblowing were analyzed. Furthermore, bottom-blowing CO2 in EAF can facilitate the carbon-oxygen reaction reaching equilibrium and decrease the content of nitrogen in molten steel due to its special metallurgical properties. Pulsating bottom-blowing in EAF can effectively improve the molten bath stirring through the action of the unsteady bottom blowing gas streams, which could make the fluid flow field more disorderly than the steady bottom-blowing. And submerged O2 injection with CO2 in EAF can noticeably strengthen the EAF molten bath stirring, increase the production efficiency and improve the molten steel quality.
基金Supported by Yunnan Fundamental Research Projects(Nos.202301AT070469,202301AT070275)supported by Yunnan Major Scientific and Technological Projects(No.202202AG050002).
文摘In bottom-blown copper smelting processes,oxygen-enriched air is typically injected into the melt through a lance,generating bubbles that ascend and agitate the melt,enhancing mass,momentum,and heat transfer within the furnace.The melt’s viscosity,which varies across reaction stages,and the operating conditions influence bubble size and dynamics.This study investigates the interplay between melt viscosity and bubble diameter on bubble motion using numerical simulations and experiments.In particular,the volume of fluid(VOF)method andΩ-identification technique were employed to analyze bubble velocity,deformation,trajectories,and wake characteristics.The results showed that bubble ascent velocity increases with bubble size and decreases in viscosity,though viscosity variations minimally affect the maximum velocity.Larger bubbles or those in less viscous melts exhibit greater deformation.Bubbles ascend primarily in straight trajectories with minor lateral oscillations regardless of viscosity.In terms of wake dynamics,vortex sizes grow as viscosity decreases,with bottom-formed vortices expanding significantly with increasing bubble size,while lateral vortices are less influenced.
基金financially supported by the National Natural Science Foundation of China (No. 51620105013)Dongying Fangyuan Nonferrous Metals Co., Ltd.
文摘In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.
