Life Cycle Assessment of Mine Water Resource Utilization in China: A Case Study of Xiegou Coal Mine in Shanxi Province

Climate change and water scarcity are two global challenges. Coal mining is the main source of carbon emissions. The utilization of mine water resources and its carbon footprint calculation are of paramount significance in promoting water conservation and carbon reduction in mining areas. However, research on the carbon footprint and other environmental indicators across the life cycle of mine water in developing countries, such as China, remains limited. This study focuses on a representative mine water resource utilization system in China and describes the method used to calculate carbon emissions associated with mine water resource utilization throughout its life cycle. Based on life cycle assessment (LCA) and using on-site investigations and analysis of environmental indicators, the study evaluates the environmental impacts at different stages of mine water resource utilization, identifies key processes, and provides some improvement suggestions. The research results indicate that the life cycle carbon emissions of mine water amount to 2.35 kg CO2 eq per 1 m3. The water extraction stage highlights the potential environmental impact, including water use (WU) and ozone depletion potential (ODP). By substituting traditional power generation methods and incorporating intelligent dosing equipment to optimize chemical usage, the global warming potential (GWP) has been decreased by over 90%, and the GWP of chemical consumption has also witnessed respective reductions of 21.5% and 10.1%. This study can serve as a basis for calculating carbon emissions in mining areas and formulating strategies to reduce their environmental impact.