322 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 47, NO. 1, JANUARY/FEBRUARY 2011 Removal of Metallic Particles From Acrylonitrile Butadiene Styrene Wastes Using Electrostatic Separation Methods Alexandru Iuga, Senior Member, IEEE, Adrian Samuila, Member, IEEE, Vasile Neamtu, Roman Morar, Senior Member, IEEE, Radu Beleca, Member, IEEE, Subhankar Das, Member, IEEE, and Lucian Dascalescu, Fellow, IEEE Abstract—Electrostatic separation techniques have been widely used in the recycling industry. The aim of this paper is to assess the possibility of employing them for the beneficiation of the newest and fastest growing category of wastes: the “end-of-life” informa- tion technology equipment. The study was performed on samples extracted from a granular acrylonitrile butadiene styrene (ABS) product obtained after the disassembling and shredding of infor- mation technology wastes. The samples that typically contained less than 0.1% metals in weight were processed in a laboratory electrostatic separator that enabled the reproduction of the two most important electrode configurations employed in the industry. The design-of-experiments methodology was employed for evalu- ating the effects of the various electrical and mechanical control variables on the outcome of the separation process. The reported data demonstrate that, by the appropriate adjustment of the input variables of either a plate-type electrostatic separator or a roll- Manuscript received December 15, 2007; accepted March 12, 2010. Date of publication November 9, 2010; date of current version January 19, 2011. Paper MSDAD-10-102, presented at the 2007 Industry Applications Society Annual Meeting, New Orleans, LA, September 23–27, and approved for publication in the IEEE TRANSACTIONS ON I NDUSTRY APPLICATIONS by the Electrostatic Processes Committee of the IEEE Industry Applications Society. A. Iuga, V. Neamtu, and R. Morar are with the High-Intensity Electric Fields Research Laboratory, Technical University of Cluj-Napoca, 40020 Cluj-Napoca, Romania (e-mail: Alexandru.Iuga@et.utcluj.ro; Vasile.Neamtu@ et.utcluj.ro; Roman.Morar@et.utcluj.ro). A. Samuila is with the High-Intensity Electric Fields Research Laboratory, Technical University of Cluj-Napoca, 40020 Cluj-Napoca, Romania, and also with the Electrostatics of Dispersed Media Research Unit, Electrohydrody- namics Group, P’ Institute, UPR 3346, Centre National de la Recherche Scientifique-University of Poitiers-L’Ecole Nationale Supérieure de Mécanique et d’Aérotechnique, University Institute of Technology at Angoulême, 16021 Angoulême Cedex, France (e-mail: (Adrian.Samuila@et.utcluj.ro). R. Beleca was with the Electrostatics of Dispersed Media Research Unit, Electrohydrodynamics Group, P’ Institute, UPR 3346, Centre National de la Recherche Scientifique-University of Poitiers-L’Ecole Nationale Supérieure de Mécanique et d’Aérotechnique, University Institute of Technology at Angoulême, 16021 Angoulême Cedex, France. He is now with the Centre for Electronics Systems Research, Brunel University, Uxbridge, UB8 3PH U.K. (e-mail: Radu.Beleca@brunel.ac.uk). S. Das was with the Electrostatics of Dispersed Media Research Unit, Electrohydrodynamics Group, P’ Institute, UPR 3346, Centre National de la Recherche Scientifique-University of Poitiers-L’Ecole Nationale Supérieure de Mécanique et d’Aérotechnique, University Institute of Technology at Angoulême, 16021 Angoulême Cedex, France. He is now with General Elec- tric India Technology Center Pvt. Ltd., Bangalore 560 066, India (e-mail: subhankar.das@gmail.com). L. Dascalescu is with the Electrostatics of Dispersed Media Research Unit, Electrohydrodynamics Group, P’ Institute, UPR 3346, Centre National de la Recherche Scientifique-University of Poitiers-ENSMA, University Institute of Technology at Angoulême, 16021 Angoulême Cedex, France (e-mail: lucian.dascalescu@univ-poitiers.fr). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TIA.2010.2091188 Fig. 1. Materials to be recycled from a personal computer. type corona-electrostatic installation, it is possible to remove all the metallic particles from the ABS product, while keeping at a mini- mum the quantity of plastics lost in the rejected conductive fraction. Index Terms—Acrylonitrile butadiene styrene (ABS), corona discharge, electrostatic separation, industrial waste. I. I NTRODUCTION I NFORMATION TECHNOLOGY (IT) waste is a category that barely existed 20 years ago. Today, it represents the fastest growing manufacturing waste. It is estimated that there are over a billion personal computers in the world. In developed countries, these have an average life span of only two years. In the U.S. alone, there are over 300 million obsolete computers [1]. These facts justify the ever-increasing interest toward the recycling of IT waste [2], [3]. On average, a computer is 30% plastic, 29% ferrous metals, 14% nonferrous metals (copper, aluminium, lead, cadmium, antimony, beryllium, chromium, and mercury), and 27% glass and ceramics (see Fig. 1). Only about 50% of the computer is recycled, and the rest is dumped. However, technologies are being developed, and solutions exist for the recycling of end- of-life computers and their components. General routes that may be followed for recycling comprise the following: 1) com- ponent recycling via disassembly; 2) materials recycling via mechanical processing, pyrometallurgy, and hydrometallurgy; and 3) a combination of these techniques [4]. The vast majority of IT wastes are subject to a mechanical treatment involving shredding, granulation, magnetic separa- tion, and classification (see Fig. 2). Plastics must be sorted prior to mechanical recycling. At the moment, most sorting for mechanical recycling is done by trained operators who manually classify the plastics into polymer type and/or color. Technology is being introduced to sort plastics automatically, 0093-9994/$26.00 © 2011 IEEE