Agglomeration of Waste Iron-oxide for use in Steel Making

Abstract

Burnt lime is traditionally used as a flux material in Basic Oxygen Furnace (BOF). However, it often creates problems in operation owing to its high melting point (2700°C), poor dissolution property, fines generation and hygroscopic nature. Since, Fe203-CaO has eutectic melting point of 12302C at 22% CaO, a flux in combination of Fe203 and CaO can easily melt and form basic oxidising slag at the very beginning of the blow and alleviate the above drawbacks. Studies of several investigators in this regard have been mentioned in this paper. NML's approach is also presented with some important results which show that fluxed lime iron-oxide pellets (FLIP) developed through binder-less room temperature process have better potential in making, cold handling and ease of operation. It shows excellent refining performance (25% less refining time) in comparison with conventional flux charging. This refining performance can be improved further by using super-fluxed sinter developed at NML through coke-breeze free sintering.