Environmental Impact of Electricity Consumption in Crushing and Grinding Processes of Traditional and Urban Gold Mining by Using Life Cycle Assessment (LCA)

Mining is not only an essential component of social and economic development since prehistoric time, but it also gives a large impact on our civilization. Gold is a noble metal that is highly valued. The extraction of minerals from earth is known as traditional mining. Gold also can be extracted from electronic waste or e-waste, and this new concept is called urban mining. There are many stages in traditional and urban mining process. However, in this study, the focus was on crushing and grinding processes to produce 1 kg of gold. Crushing and grinding are processes in the milling stage. This research evaluates and compares the environmental impacts of crushing and grinding processes, based on electricity consumption. About 50 to 65% of total electricity in milling was used for crushing and grinding processes. Life Cycle Assessment (LCA) methodology was used as a tool to evaluate the environmental burdens of electricity usage in converting ore and electronic waste to gold bars. The Life Cycle Impact Assessment (LCIA) of this process was interpreted by using Eco-indicator 99 assessment methods in SimaPro software. The impact categories included in this study were carcinogens, respiratory organics, respiratory inorganics, radiation, climate change, ozone layer, ecotoxicity, acidification or eutrophication, land use and minerals. The results showed that crushing and grinding from traditional mining gave the largest impact to the environment with single score of 399 Pt compared to the urban mining with only 1.81 Pt score. The highest impact in both types of mining is to human health.