日本国内における小型電気・電子機器用途の金の消費量・ストック量および使用済み機器中の含有量の推計

概要

論文の詳細を見る
The recovery of gold from secondary sources like electronic wastes has received much attention because of the many industrial applications and high market prices of precious metal. Electrical and electronic equipments (EEEs) account for approximately 10% of annual demand for gold in Japan as well as in the world. Therefore, waste of EEEs (WEEEs) contains much amount of gold, whose grade can be much higher than that of natural ore. Substance flow analysis (SFA) is a useful tool for determining the flow and in-use stock of substances in specific geographic regions. In this work, we estimated the annual consumption and in-use stock of gold for small EEEs, and the amount of gold contained in discarded EEEs during 1984-2012. As a result, the maximum amount of consumption for EEEs production, in-use stock in EEEs and discard in WEEEs were 8.87 t in 2006, 44.5 t in 2005 and 6.90 t in 2008, respectively. Mobile phone accounted for the largest share of the recent consumption and discard of gold, whereas, audio system has accounted for the largest share of the in-use stock for many years. This difference was caused by the average lifetimes and parameters of Weibull distributions for EEEs.
The Japan Institute of Metals and Materialsの論文