تعيين عوامل جذب نيتروژن در فرايند فولادسازي مجتمع فولاد مباركه

Determination of Nitrogen Absorption Factors in Steelmaking processes in Mobarake Steel Company

Nowadays, there is a great tendency to decrease the amount of nitrogen content in steels in steelmaking process. Nitrogen decreases the fracture toughness, weldability and properties of weld metal. In this research, effective factors on absorption of nitrogen in steelmaking process have been determined. So nitrogen content in four major stages in steelmaking including melting in electric arc furnace (EAF), melt transmission from EAF to LF (ladle furnace), secondary metallurgy in LF and continuous casting (CCM) have been examined. Results showed that nitrogen content is increased by increasing the amount of Lime and DRI in casting stage. It was indicated that by using Graphite at the bottom of ladle and also increasing slag thickness as well as its fluidity, nitrogen content decreases. Moreover by decreasing process duration and also temperature of various stages as possible, nitrogen absorption will grow down.