Experimental Study on the Relation between Microstructures of Constituent Minerals and Pores and Reducibility of Sinter

Abstract

Effects of the microstructures of constituent minerals and pores on the reducibility of sinter were investigated by using six kinds of sinter having different basicity.
1) The reducibility of small particle sinters (0.8 mm in dia.) which contain few macro-pores increases with an increase in basicity and has a good correlation with the microstructure of the sinters. Sinters which are mainly composed of hematite and calcium ferrite are reduced much faster than sinters mainly composed of magnetite and slag.
2) The reducibility of sinters of spherical form (12 mm in dia.) is not necessarily correlated with the basicity but is definitely affected by the porosity of the sinters, especially by the content of macro-pores.
3) It is concluded from these findings that the intrinsic reducibility of a sinter is determined by the microstructures of constituent minerals and micro-pores but that the macro-pores which supply reducing gas to each mineral grain also play an important role in determining the overall reducibility of the sinter.