Utilization of aluminum dross: Refractories from industrial waste
AlN removal; Aluminium dross; refractories; synthesis
Aluminum oxide (Al2O3) and Magnesium-Aluminum oxides (MgAl2O4) are well known refractory materials used in engineering industries. They are built to withstand high temperatures and possess low thermal conductivities for greater energy efficiency. Dross, a product/byproduct of slag generated in aluminum metal production process is normally comprised of these two oxides in addition to aluminum nitride (AlN). Worldwide, thousands of tons of aluminum dross are generated as industrial wastes and are disposed of in landfills causing serious environmental hazard. This paper explores the potential to synergize the characteristics of the favourable contents of aluminum dross and its availability (in tons) via synthesis of refractories and thereby develop a value added product useful for the modern industries. In this work, Al-dross as-received from an aluminum industry which comprised of predominantly Al2O3, MgAl2O4 and AlN, was used to develop the refractories. AlN possesses high thermal conductivity values and therefore was leached out of the dross to protect the performance of the developed refractory. The washed dross was calcined at 700 and 1000C to facilitate gradual elimination of the undesired phases and finally sintered at 1500C. The dross refractory pellets were subjected to thermo-physical and structural properties analysis: XRD (structural phase), SEM (Microstructure), EDS (chemical constituents) and thermal shock cycling test by dipping in molten aluminum and exposing to ambient (laboratory). The findings include the favourable prospects of using aluminum dross as refractories in metal casting industries. Published under licence by IOP Publishing Ltd.
Ramaswamy P.; Gomes S.A.; Ravichander N.P.
IOP Conference Series: Materials Science and Engineering, Vol-577, No. 1
Ramaswamy P., Department of Mechanical and Automobile Engineering, Faculty of Engineering Christ, Deemed to Be University, Kengeri Campus, Bangalore, 560074, India; Gomes S.A., Department of Mechanical and Automobile Engineering, Faculty of Engineering Christ, Deemed to Be University, Kengeri Campus, Bangalore, 560074, India; Ravichander N.P., Department of Mechanical and Automobile Engineering, Faculty of Engineering Christ, Deemed to Be University, Kengeri Campus, Bangalore, 560074, India