Effect of Na2CO3 on reduction and melting separation of ludwigite/coal composite pellet and property of boron-rich slag

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.