Laboratory investigation of denitrogenation of low carbon steel by gas generation in situ

Abstract

Denitrogenation of low carbon steel with carbon monoxide generated in situ by the reaction of carburised iron /graphite with dissolved oxygen in the bath has been investigated in an air induction furnace. A melt size of 50 kg was used. Experimental parameters, namely nature and size of the deoxidising reactants and bath parameters, such as dissolved carbon, nitrogen and oxygen levels in the bath and temperature of the bath, were varied to investigate effects on the extent of denitrogenation. A trend of increasing denitrogenation with increasing gas evolution in the bath was observed. The extent of denitrogenation showed a decreasing trend with increasing temperature and oxygen level in the bath. Thermodynamic consistency was checked by calculating the average partial pressure of desorbed nitrogen from the total gas generated and the total volume of nitrogen liberated at the reaction site.