Electronic Waste

This chapter provides an overview of electronic waste, current status of the management of electronic waste (e-waste), and recycling technologies for the recovery of metals from end-of-life electronic equipment. Because of the ever increasing generation of e-waste and the hazardous nature of this waste stream, e-waste is an emerging issue. Many countries have drafted legislation to improve the reuse, recycling, and other forms of recovery of such waste. Electronic waste is significantly heterogeneous and complex in terms of the type of components and materials. However, copper and precious metals make up more than 80% of the value for most of the e-waste samples. This indicates that the recovery of precious metals and copper may remain as the major economic driver for a long time. The hierarchy of treatment of e-waste encourages the reuse of the whole equipment first, remanufacturing, then recovery of materials by recycling techniques, and as a last resort, disposal by incineration and landfilling. Recycling of e-waste can be broadly divided into three major steps—selective disassembly, targeting, and singling out hazardous or valuable components for special treatment; mechanical and metallurgical processing to upgrade desirable materials content; and refining recovered materials that are retreated or purified by using chemical (metallurgical) processing so as to be acceptable for further use in their original application.