Process models are very useful to control high efficient industrial metallurgical processes.However their accuracy depends strongly on the choice of boundary conditions and thermodynamic as well as kinetic data used. ...Process models are very useful to control high efficient industrial metallurgical processes.However their accuracy depends strongly on the choice of boundary conditions and thermodynamic as well as kinetic data used. Whereas the commercial data base FactSage or Thermocalc is used as the source of thermodynamic data the kinetic parameter are characteristic for each process and process design.Therefore it is essential to estimate the kinetic parameter in well designed experiments supported by using of numerical methods. In this paper the steel melt flow parameter,gas-melt interfacial area and mass transfer coefficient obtained in 30t industrial gas stirred ladles are described.On the example of nitrogen absorption and desorption the predictive process model for nitrogen control while ladle treatment and decarburisation process is presented for different steel alloys.The modelling results are compared with results from industrial processes.展开更多
Controlling conditions for inclusion plasticization were calculated by FactSage, and the steel/slag reaction equilibration time was determined by pre-equilibrium experiments. Laboratory experiments with different top ...Controlling conditions for inclusion plasticization were calculated by FactSage, and the steel/slag reaction equilibration time was determined by pre-equilibrium experiments. Laboratory experiments with different top slags were carried out in 90 rain, and industrial tests were performed based on the results of calculation and laboratory experiments. Scanning electron microscopy （SEM） and energy-dispersive spectroscopy （EDS） were used to determine the morphology and composition of inclusions in tire cord steel. It is found that the shape of in- clusions can be controlled well, and the composition of inclusions varies in the industrial test as the following transformation route： MnO-A1EOa-SiO2→CaO-AIEOa-SiO2→MnO-A1203-SiO2. Inclusion plasticization can be achieved by controlling the binary basicity of top slag （CaO/SiO2 by mass） around 1.0 and the （A1203） content in top slag below 10wt%. Under these controlling conditions in the industrial test, almost all of inclusions in the wire rods achieve plastic deformation.展开更多
In ladle metallurgical process,two liquid layers,a metallic layer below a salty or oxide layer,are separated by an interface where mass transfers occur thanks to redox reactions.Such mass transfers are strongly depend...In ladle metallurgical process,two liquid layers,a metallic layer below a salty or oxide layer,are separated by an interface where mass transfers occur thanks to redox reactions.Such mass transfers are strongly dependent on the stirring of each phase.By means of induction,a cold crucible reactor can melt,confine and stir,without any physical contact,liquids at very high temperature,with opportunities for continuous treatment.To work on metal/salt couples of interest to industry,we built a facility to control and measure the full kinetic transfer of a pollutant from one layer to another.A numerical simulation of the experimental reactor is presented here.We calculate the flows in both salty and metallic layers taking into account of all the present phenomena in each liquid phase(i.e.electromagnetic stirring, buoyancy,turbulence)as well as at the interface(i.e electromagnetic shaping,viscous shear driving).The implementation of the couplings needed for the complete simulation is presented.A focus is done on the numerical description of the shear stress near the interface.Stationary flows for two inductor positions complete this short article.展开更多
文摘Process models are very useful to control high efficient industrial metallurgical processes.However their accuracy depends strongly on the choice of boundary conditions and thermodynamic as well as kinetic data used. Whereas the commercial data base FactSage or Thermocalc is used as the source of thermodynamic data the kinetic parameter are characteristic for each process and process design.Therefore it is essential to estimate the kinetic parameter in well designed experiments supported by using of numerical methods. In this paper the steel melt flow parameter,gas-melt interfacial area and mass transfer coefficient obtained in 30t industrial gas stirred ladles are described.On the example of nitrogen absorption and desorption the predictive process model for nitrogen control while ladle treatment and decarburisation process is presented for different steel alloys.The modelling results are compared with results from industrial processes.
基金supported by the Major State Basic Research and Development Program of China (No.2010CB30806)
文摘Controlling conditions for inclusion plasticization were calculated by FactSage, and the steel/slag reaction equilibration time was determined by pre-equilibrium experiments. Laboratory experiments with different top slags were carried out in 90 rain, and industrial tests were performed based on the results of calculation and laboratory experiments. Scanning electron microscopy （SEM） and energy-dispersive spectroscopy （EDS） were used to determine the morphology and composition of inclusions in tire cord steel. It is found that the shape of in- clusions can be controlled well, and the composition of inclusions varies in the industrial test as the following transformation route： MnO-A1EOa-SiO2→CaO-AIEOa-SiO2→MnO-A1203-SiO2. Inclusion plasticization can be achieved by controlling the binary basicity of top slag （CaO/SiO2 by mass） around 1.0 and the （A1203） content in top slag below 10wt%. Under these controlling conditions in the industrial test, almost all of inclusions in the wire rods achieve plastic deformation.
基金Item Sponsored by the CNRS/CEA Program on the Use of Molten Salts in Nuclear Applications (PCR ANSF) for Reprocessing of Nuclear Reactor Salt Operating on a Cycle Th/U
文摘In ladle metallurgical process,two liquid layers,a metallic layer below a salty or oxide layer,are separated by an interface where mass transfers occur thanks to redox reactions.Such mass transfers are strongly dependent on the stirring of each phase.By means of induction,a cold crucible reactor can melt,confine and stir,without any physical contact,liquids at very high temperature,with opportunities for continuous treatment.To work on metal/salt couples of interest to industry,we built a facility to control and measure the full kinetic transfer of a pollutant from one layer to another.A numerical simulation of the experimental reactor is presented here.We calculate the flows in both salty and metallic layers taking into account of all the present phenomena in each liquid phase(i.e.electromagnetic stirring, buoyancy,turbulence)as well as at the interface(i.e electromagnetic shaping,viscous shear driving).The implementation of the couplings needed for the complete simulation is presented.A focus is done on the numerical description of the shear stress near the interface.Stationary flows for two inductor positions complete this short article.
