Characterizing the environmental implications of the recycling of non-metallic fractions from waste printed circuit boards

Non-metallic fractions (NMFs), which make up almost three fourths (by weight) of waste printed circuit boards, have become a matter of great concern for e-waste recyclers, because most of them contain hazardous substances with low utilization value. This study used an advanced Sales Obsolescence Model approach to quantify the generation and flows of non-metallic fractions in China, and to examine the potential environmental impacts associated with both the fractions themselves, and their end-of-life processing activities: disposal into landfills or incineration, and recycling via physical or chemical methods. The results show that approximately 201,000 tons (one time standard deviation: 67,000) of scrap non-metallic fractions were expected to be generated in 2015, and that this amount could increase to 279,000 tons by 2020. Both our own analysis and a systematic review of existing studies on the hazardous characterization of printed circuit boards waste, non-metallic fractions, and their recycling and disposal activities, indicate the threat of environmental pollution, from heavy metals, brominated flame retardants and secondary persistent organic pollutants, particularly dioxins. (C) 2016 Elsevier Ltd. All rights reserved.