Investigation of the effect of waste plastic addition on reduction behavior of iron ore pellets

Traditionally, the method of iron and steel production facilities are based on the blast furnace. In the blast furnace method, iron ore charged in the form of lump ore, pellets or sinter. Together with a sufficient amount of ore and flux, fuel oil or mostly coke is used as a reductant. Dependence on such a high rates of coke, leads to the use of high quantities of coke. The development of new production technologies and reducing dependence on coal provides a significant contribution to iron and steel industry. Nowadays, various production methods have been developed based on using low quality ores and composite pellet which include its self reductant. One of these methods is ITmk3 process which carried out at relatively low temperatures (1350°C -1400°C) and in short times. Thanks to low temperatures and short reduction times, energy and time is saved in this process. In the ITmk3 process, coke is used as reductant and successful results obtained up to now. Depends on improving technology using of plastics in the world increases day by day and the amount of waste plastics increase as a result of high consumption. The long degradation period of plastics in nature cause the plastic wastes to be a major problem for environmental damage and pollution. By recycling of plastics these problems can be eliminated. For this aim plastics can be used as alternative reductant for iron and steel industry instead of coke. Additionally, high production cost and high consumption of coke has always been the primary problem of iron and steel industry. The aim of this study is reduction of costs due to coke consumption in iron making and environmental damage caused by waste plastics. By this aim waste plastics were added to composite pellets as reductant. In this study PET (Polyethylene terephthalate) which is the remarkable percent of plastic wastes, was used due to its high carbon content. In the experiments, composite pellets which contain PET wastes, coke and magnetite iron ore were prepared. After that, composite pellets were reduced at relatively high temperatures during various reduction times in order to investigate its behavior during reduction melting process.