Effect of mineralogical properties of iron ore on pore formation of sinter

The effects of mineralogical properties of iron ores on the pore formation in the sintering process have been examined from view points of partical si ze, combined water content and structure of iron oxide. Quasi-particles consist of nulear ores coated with limestone (-0.5 mm and t he ratio of CaO to ore (CaO/Ore) was 0.1 and 0.2) have been made by granula ting with water, and heat treated by the electric furnace that simulated th e heating pattern in an actual sintering process. The porosity of sintered specimen was determined by using the image analysis. It was found that the porosity of sinterd specimen was increased with the i ncrease in the combined water contents significantly, whereas was not affec ted by the particle size in the range of 1.0-4.75 mm. However, Indian high- goethite ore had low porosity of sintered specimen in spite of high combine d water contents. It was presumed that the martite was converted into the d ense structure and the melts penetrated into the cracks of,goethite during heating. It was concluded that, in order to control of the pore formation of sinter, the ratio of CaO/Ore should be determinted by the combined water contents of the iron ores as nuclei of quasi-particles and the structure of iron oxi des.