Recycling Mixed Plastic Waste And Its Blend With Sawdust As Reductant In Ironmaking

One of the major obstacles to the implementation of an appropriate plastics recycling scheme is the inhomogeneity of many plastics waste. Accordingly, most of the existing recycling schemes require a feedstock that is reasonably pure and contains only items made from a single polymer type. This often requires sorting into different polymer fractions, a process that is both cumbersome and expensive. This work therefore investigates the reduction of two sources of iron oxide by mixed plastic waste (MPW) and its blend with sawdust (SD) through experiments conducted in a laboratory scale horizontal tube furnace. Composite pellets of EAF slag (47.1% FeO) with a blend of MPW and SD were rapidly heated at 1520 degrees C under high purity argon gas and the off gas was continuously analysed for CO, and CO2 using an online infrared gas analyser (IR). The extent of reduction after fifteen minutes was determined for each carbonaceous reductant. The results show that iron oxide can be effectively reduced to produce metallic iron using MPW and its blend with SD as reductant. An improvement in extent of reduction was observed over conventional metallurgical coke and the individual polymers when the blend (MPW+ SD) was used as reductant. This eliminates the need to sort out individual plastics from municipal solid waste for their effective utilisation as reductants, carburisers and desulphurisers in iron making.