Mathematical model for the forced oxygen blowing decarburization process of ultra-low carbon steel during RH treatment

A new mathematical model for the RH forced oxygen blowing decarburization process which takes the influence of post combustion on decarburization into account is established. Decarburization reactions are considered to take place at four reaction sites. The simulated results of carbon and oxygen contents show relatively good agreement with the experimental data under different oxygen flow rates. At the rapid decarburization stage including the O-2 blowing process, 66.1% of the total decarburization amount is removed. By using the forced oxygen blowing decarburization process, the decarburization rate in the bulk steel is improved most significantly. Additionally, the effects of oxygen flow rates on carbon, oxygen and total decarburization rate are evaluated in detail. At 1500 m(3 )center dot h(-1), the oxygen content is adequate to completely remove carbon of molten steel in the vacuum vessel during the O-2 blowing. Combining with the analysis of oxygen flow rates on the decarburization rate at each site, 1500 m(3 )center dot h(-1) is chosen as the critical oxygen flow rate to achieve the best decarburization performance. The influences of other parameters including initial carbon and oxygen contents and oxygen utilization rate on decarburization are also investigated.