Life Cycle Inventory Analysis of CO_2 Emission from Copper Products Manufacturing System

摘要

CO_2 emissions from the copper products manufacturing system were quantitatively evaluated using Life Cycle Assessment (LCA) technique. Copper and brass products in several shapes, copper cable and sulfuric acid were produced in this system. In this study, inventories such as the fuel consumption of the processing and the in-house electricity were based on public statistical data. The following observations were made based on LCI analysis: (1) CO_2 emissions from the copper products in the system are in the range from 1.4kg to 2.24kg/kg-product, respecting the materials consumption and the energy consumption to process the products. The CO_2 emission attributable to the processing corresponds to 50 percent of all emissions. (2) The reduction effects of CO_2 emissions from the system are larger with the recycling of copper alloy scrap to the brass processing than that to the converter, if the amount of scrap consumption is fixed. The reduction is estimated to be 50,000 t-CO_2 at the point of 0.1 kg/kg-brass processing with scrap additive. However, the recycling leads to the decrease of sulfuric acid.The recycling of scrap should be evaluated not only from the reduction of CO_2 emissions but also in terms of land use and so on.