Porosity of Sinter and Its Relation with the Sintering Indices

摘要

The reducibility of sinter is well correlated with the proportion of micro-pores (pore radius in the 0.001-10 mu m range) out of total pores consisting of micro-pores and macro-pores (pore radius - 100+10 mu m) available in the sinter. With the change in process parameter(s), the micro-porosity of the sinter samples is significantly affected while total porosity of the sample may remain more or less same or marginally affected. The micro-porosity of sinter samples (pore radius in the 0.001-10 mu m range) and consequently the sinter reducibility increase with decrease in the size range of coke breeze. That is, when coke breeze below 6.3 mm size is screened at 3.3 mm and +3.3 mm size fraction is crushed and mixed to the -3.3 mm size fraction (100 percent, -3.3 mm sized coke breeze). Sintering of ore fines with reduced size increases micro-porosity of the sinter sample. Besides, the average pore radius and density of the sinter sample and consequently the sinter reducibility increase with narrowing down the ore size from -8 to -6.3 mm. The micro-porosity and reducibility of the sinter samples increases marginally with the replacement of pyroxenite by dolomite.