Effects of operational factors on the formation of toxic organic micropollutants in EAF steelmaking

Electric arc furnace (EAF) steelmaking is an important route for the production of steel and approximately 38% of the total steel output in the EU is produced in this way. Furthermore, it is envisaged that the proportion of steel produced by the EAF process will be maintained, or perhaps increased in the next twenty years or so. The EAF route is particularly important because of its role in the recycling of steel scrap and its importance in this respect seems likely to increase as a result of the European Directive 94/612/EC on Packaging and Packaging Waste and other Directives on End of Life Vehicles and Waste from Electrical and Electronic Equipment. However, EAF plants are significant sources of organic pollutants such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and volatile organic compounds (VOC). Emission limits for some of these species are already applied in some European countries and it is expected that these will become tighter and more uniformly applied across the whole of the EU in the near future. Clearly, a better understanding of the fundamental factors that influence the formation of PAHs, PCBs and PCDD/Fs would be of considerable benefit in preventing, or minimising the formation of these substances in EAFs and in scrap pre-heating systems on EAFs. However, it must also be recognised that secondary abatement measures may still be required to meet stricter emission limits that are likely to be applied in the future.