Application of Microwave Energy for Production of Iron Nuggets from the Pudo Iron Ore using ‘Pito’ Waste and its Blend with HDPE as Reductant

Abstract

The local steel industry is currently facing stiff competition from South East Asia and elsewhere for high grade scrap iron, culminating in a ban by central Government on the export of ferrous scrap. In this work we investigate the potential for producing high grade iron nuggets from the Pudo iron ore in the Upper West Region of Ghana, using carbonaceous materials generated from locally available ‘pito’ waste and its blend with high density polyethylene (HDPE) as reductant. Composite pellets of the ore containing various blends of uncharred ‘pito’ and charred ‘pito’ waste with HDPE were irradiated in a domestic microwave oven and the extent of reduction was determined after 40 min of irradiation. It was observed that highly carburised premium grade iron nuggets can be produced from the Pudo iron ore using ‘pito’ waste (both charred and uncharred) and its blends with HDPE as reductant. The measured extent of reduction ranged from about 47 % to about 96 %, suggesting that the Pudo iron ore is a potential source of iron from which premium grade metallic iron can be produced commercially to feed the local steel industry. From the point of view of chemical reactivity, it appears the effect of hydrogen is more pronounced than the amount of fixed carbon in the ‘pito’ waste and this effect was felt in all the HDPE-‘pito’ waste blends utilised for the investigation. Accordingly dry ‘pito’ waste may be used directly with HDPE as reductant without the need to char the biomass.   

Keywords: Reduction, Pudo Iron Ore, Waste Biomass, Pito Waste, Extent of Reduction