Evaluating the environmental impacts of tin ingot production in China: Insight from life cycle assessment

Abstract

Tin is an indispensable metal for contemporary society, but its extraction processes result in adverse environmental impacts. A comprehensive environmental impact assessment of tin ingot production is crucial to enhance the environmental transparency of downstream products. However, few studies have examined the environmental impacts of tin production, and none have focused on tin ingot production from mining to smelting in China, the global top producer of refined tin. This research endeavors to address this gap by examining the potential environmental impacts of tin ingot (99.95 % tin) production in China for the first time using a life cycle assessment that includes the mining, beneficiation, and smelting stages. An uncertainty analysis was conducted using a Monte Carlo simulation to provide reliable results for stakeholder decision-making. The results showed that the potential environmental impacts on resources, human health, and ecosystem quality from producing one ton of tin ingot were 1.16 × 10⁶ $, 0.10 disability-adjusted life years, and 1.57 × 10⁻³ Species·year, respectively. The inputs of tin and natural gas in the ground and the emissions of particulates, carbon dioxide, chromium VI, mercury, and iron, were major contributors to the potential environmental burden. These substances primarily originated from the production of tin ore, steel, explosives, freshwater, and natural gas, and direct on-site emissions associated with tin ingot production. Several recommendations were then proposed to promote the sustainable development of tin industry based on these results. These included the promotion of tin recycling, the adjustment of energy structure, the implementation of carbon labeling certification, the use of economic instruments, and the promotion of international cooperation. These findings (e.g., life cycle inventory, impact assessment results, key contributing factors, and recommendations) will provide valuable insights to stakeholders seeking to diminish the environmental strain of the tin and metallurgical industries.