Abstract:The effects of Na₂CO₃ on the reduction and melting separation behavior of ludwigite/coal composite pellet, the desulfurization ratio and the property of the separated boron-rich slag were investigated at laboratory scale in the present work. Na₂CO₃ could improve the reduction rate of the composite pellet to some extent. The melting separation of the composite pellet became increasingly difficult with the increase of Na₂CO₃ in the pellet due to the sharply increasing of the melting point of slag. The sulfur content of the iron nugget gradually decreased from 0.27% to 0.084% (mass fraction) with the Na₂CO₃ content in the pellet increasing from 0 to 6%. The efficiency of extraction of boron (EEB) of the slow cooled boron-rich slag decreased from 86.46% to 59.52% synchronously. Na₂CO₃ had obviously negative effect on melting separation of the composite pellet and boron extraction of the boron-rich slag.

Key words: ludwigite; carbon composite pellet; reduction and melting separation; desulfurization; boron-rich slag; boron extraction