Highlights
Abstract
Graphical abstract
Keywords
1. Introduction
2. Materials and methods
3. Results
4. Discussion
5. Conclusion
CRediT authorship contribution statement
Declaration of competing interest
Acknowledgments
References
Abstract
Coal is not only the main fossil fuel in China but also a pollution source. To evaluate the impact of coal production on the environment, a life cycle assessment (LCA) was conducted on the mining process of a typical coal mine in China by using the SimaPro 9.0.0 software. The Ecoinvent v3 database was used to provide the background data, and midpoint results with uncertainty information were calculated using the ReCiPe Midpoint (H) method. After normalising the midpoint results, fossil depletion was identified as the most predominant environmental impact category, followed by marine ecotoxicity, freshwater ecotoxicity, climate change, freshwater eutrophication, and human toxicity. The contribution analysis indicates that coal mining activities, consumption of steel and electricity, and mine ventilation are the key processes causing the above-mentioned environmental impact categories, which should be paid special attention. According to the sensitivity analysis, the primary countermeasures for addressing the environmental issues are to reduce the mining activities and improve the efficiency of coal mining and utilisation. In addition, the quantitative and comparative analyses show that the gas extraction production mode is beneficial to the environment. Finally, technical measures were proposed to promote green and sustainable development of the coal industry. This research can provide guidance for ensuring national energy security and promoting healthy development of the national economy.
1. Introduction
Since 2012, the annual output of raw coal in China has remained at 3.41 to 3.97 billion tonnes (SCIO, 2020). In 2020, coal accounted for 56.8% of the primary energy consumption (NBSPRC, 2021). In the next five years, coal is still expected to account for more than half of the primary energy consumption in China. It is estimated that by 2025, the coal consumption will be approximately 4.1 billion tonnes, accounting for approximately 52% (Kang, 2019). With the implementation of reforms in the energy structure, the proportion of coal consumption in China has declined, but the coal-based energy structure is expected to remain for a long time (Yuan et al., 2016). This huge energy consumption will result in a series of environmental problems, seriously threatening the ecological environment and human health. Life cycle assessment (LCA) is an effective tool for quantifying product sustainability. Because it can quantitatively describe the burden of production on the environment (ISO 14040, 2006), it has been widely used in the industrial, agricultural, and other fields, as indicated in the studies by Nabavi-Pelesaraei et al. (2019), Khanali et al. (2021), Hou et al. (2016), and Saber et al. (2021). These studies have provided important theoretical support for sustainable development. By reviewing the literature, it was found that most LCA studies on coal focused on the consumption scenario, and there were only few studies concerning production processes. Peng et al. (2021) adopted the LCA method to assess volatile organic compound emissions from coal-fired power plants in China. Tong et al. (2021) conducted a LCA on three different technical coal-to-liquid routes. Li et al. (2019) studied the impact of greenhouse gases on the life cycle of direct chemical recycling of coal for hydrogen production. Some scholars have analysed the environmental pollution caused by coal tailings (Adiansyah et al., 2017; Peng et al., 2020). The above-mentioned studies obtained many useful conclusions. Because coal production is the second largest source of emissions after coal consumption (Aguirre-Villegas and Benson, 2017), the environmental pollution due to coal production cannot be ignored.