Environmental impacts for iron ore pellet production: A study of an open pit mine through life cycle assessment

Brazil has one of the largest mineral repositories in the world and is a main producer and exporter of high-quality ores and mineral products. Mining is a strength of the Brazilian economy; however, the environmental impacts of the sector are not well understood. The objective of this study is to evaluate the environmental impacts from the production of iron ore pellets, by means of a case study in an open pit mine located in the southwest of Brazil. The study evaluates the life cycle of the pellets from the cradle to the gate including the process of mining, beneficiation, transport, and pelletizing, up to the seaport for exportation. The life cycle assessment methodology based on ISO 14040/14044 was used. The functional unit was defined as a ton of iron ore pellets with 68 % Fe content, and the data used was collected in technical visits and reports for the year 2013. The study showed that the main environmental impact in the Human Health category was particulate matter emissions during the open mining operation. In the Ecosystems category, it was climate change, due to fossil fuels combustion used in equipment operation of beneficiation stage. Finally, depletion of mineral resources was the most relevant impact in the Resource Consumption category. Hydroelectricity, the use of conveyor belts and a water reuse technology are improvements that reduce the environmental impacts.