The use of alternative materials in cement-based solidification/stabilization of electric arc furnace dust (EAFD)

Electric Arc Furnace Dust (EAFD) is an industrial waste obtained as a by-product of the stainless steel manufacturing industry. It contains heavy metals, mainly lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr) and nickel (Ni) and hence, has been listed as a hazardous waste under the code of 10 02 07* in the European Waste Catalogue. In the UK, the Waste Acceptance Criteria (WAC) has been introduced under the Landfill (England and Wales) Regulations in July 2005. The recent amendment in the UK Landfill Regulations meant that all hazardous wastes have to be pre-treated prior to landfill disposal. Therefore, according to the WAC, EAFD waste has to be pre-treated prior to disposal due to mainly the leaching potential of heavy metals it contains. Various technologies have been used to pre-treat hazardous wastes prior to landfill disposal. Solidification/Stabilization (S/S) is one technique that has been demonstrated to have potential for the treatment and possible reuse of a wide range of hazardous wastes. It mainly aims to reduce the mobility of the waste and hence reduce the leachability of pollutants of concern. S/S products can either be disposed of in landfill after pre-treatment or might be reused in the construction industry depending on the structure and chemical characteristics of the final products. Consequently, the aim of this study is two-folds; (1) to evaluate and determine the optimum process conditions for a final product that not only complies with the WAC but has also potential for reuse; (2) evaluate the potential of using cost-effective alternative materials for cement replacemen