Substance Flow Analysis of Tantalum: Tracking the Conflict-Free Path

Abstract

Tantalum is a critical material used in specialized industrial manufacturing processes and end-use applications ranging from aerospace to high performance electronics. In Central Africa severe human rights violations are associated with illicit mining and conflicts in regions where tantalum is extracted. Considerable efforts from industry, government and non-profit organizations have gone into conflict-free sourcing programs using mechanisms such as due diligence and chain-of-custody. However, a paucity of quantitative information exists on the global sources and amounts of metal, and this impedes decisions towards potential solutions. The purpose of this research was to quantify global flows of tantalum production and characterize patterns of conflict-free production. This study employed substance flow analysis (SFA) to characterize tantalum mass flows for 48 processing facilities located in 12 countries. A novel facility-level bottom-up method to SFA was employed on smelting and metal refining activities to aggregate information on global flows of metal. Results estimate the mass flows of global tantalum production and present an ostensible pattern of tantalum production. Global tantalum production in 2014 was estimated at 2800 tonnes, with a global average recycled content of about 35%, and 46 conflict-free tantalum processing facilities accounted for processing over 95% of global tantalum mineral concentrates. The emergence of conflict-free tantalum mineral sourcing from 2010 to 2014 is quantified. This research advances the SFA approach for metal flows accounting with greater facility-level detail and geographic information. The descriptive view of tantalum flows informs discussions on conflict-free programs and supports metal certification of sustainable supply chains of metals.