Study of reduction behavior of iron ore lumps by coal

Abstract

Studies on the reduction behavior of hematite iron ore (OMC Ltd.) lumps with coal at different temperatures with varying time were undertaken to understand the effect of time and temperature on degree of reduction. The experiment were carried out at three different temperatures 850 c,900 c,950 c. The holding time was also varied to 30 mins,60 mins,90 mins. Majority of iron ore lumps were found to have high iron and low alumina and silica contents. All these ores were free from impurities such as Sulphur , Phosphorous, Arsenic, Lead, Alkali elements etc. the lumps have low values of shatter , abrasion and swelling index. Proximate analysis of coal was done to determine the percentages of fixed carbon, ash, volatile matter, moisture. The reduction of iron ores were carried out in muffle furnace and were carefully monitored to avoid oxidation after being taken out of the furnace after completion of assigned time interval. The degree of reduction of iron ores were plotted against temperature and time . The results have indicated that with increase in temperature the overall percentage of reduction for the same time interval also increases. But for increased time interval the rate of reduction shows a slow decrease for holding at the same temperature.