A pretreatment method for effective utilization of copper product manufacturing waste

Abstract

In South Korea, the manufacturing system from chalcopyrite (CuFeS2) to Cu products is divided into two parts: electrolytic Cu manufacturing and Cu product manufacturing (CPM). Most of the CPM waste is deposited in landfills unlike the waste generated in electrolytic Cu manufacturing that has a good recycling ability. Therefore, in this study, a method to improve the utilization of CPM waste was proposed as a case study for South Korea. Furthermore, the CPM was investigated and classified into five types in terms of the raw materials, major products, additives, main processes, and characteristics of the CPM waste (waste type, particle size, and chemical composition). Next, the CPM waste was environmentally assessed via leaching toxicity tests using the Korean standard official method, ES 06150. In addition, the amount of specific heavy metals (Pb, Cu, Cd, As, Hg, and Cr6+) was determined to confirm the presence of substances labeled as hazardous waste. Based on these results, a pretreatment method with grinding (under 0.1 mm), screening (0.15 mm grid), magnetic separation (1.0 T), and alkali leaching (30–90 °C and 1–5 mol/dm3) was proposed. The final materials can be categorized into groups, such as fine-particle groups with high Zn and Fe contents, leachate groups with high Cu and Zn concentrations, and metal-scrap groups. Moreover, material flow analysis of all CPM waste streams in the designed pretreatment method was conducted in South Korea in 2019.