Reducing GHG global emissions from copper refining and sea shipping

Abstract

Chile is the largest copper producing country of the world; and almost 50% of the copper it exports to the rest of the world is exported as copper concentrates to be smelted and refined abroad. However, 70% of the weight of these exported copper concentrates is gangue (valueless and undesirable material associated to the copper content in these exported concentrates). In this paper analyze and quantify the contribution Chile could make to the ongoing world efforts to reduce climate change and global warming, if it adopts a trading policy eliminating its exports of copper concentrates and replacing them with the greater value added exports of the refined copper obtained from smelting and refining those concentrates in Chile. This policy would allow a significant reduction of greenhouse gases (GHG) emitted every year to the global atmosphere. This reduction would occur through two channels: 1. avoiding the combustion of more than 600,000 tons of diesel oil currently used to transport by sea almost 6,600,000 tons of the gangue incorporated in Chile's copper concentrate exports; and, 2. using Chile's cleaner technology for smelting and refining copper concentrates instead of the dirtier technologies of the countries currently importing, smelting and refining the Chilean copper concentrates. For the first time, using data for 2014, we estimate the total net reduction in GHG emissions to the global atmosphere that the proposed trade policy would imply. We calculate the distance of the nautical mutes used for the 919 shipments of concentrates exported by Chile that year; and we perform sensitivity analysis for 4 scenarios, employing two alternative values for two key parameters. Additionally, we compare the GHG emission performances of the copper smelting and refining metallurgic technologies employed in Chile and in every one of the 22 countries that import and smelt and refine Chilean concentrates. Our estimates for the 2 most extreme scenarios indicate that, if instead of exporting copper concentrates in 2014, Chile would had exported only refined copper, it would had contributed with a total net reduction of GHG emissions emitted to the global atmosphere of 2,227,047 and 2,799,279 ton CO2-eq tons that year, which are equivalent to approximately 5.6% of the total amount of GHG emissions that would had made Chile fully carbon neutral that year. This is a significant contribution regarding Chile's commitment to the Paris Agreement as well as in terms of the required world efforts to reducing GHG emissions from sea shipping.