Sulfur hexafluoride (abbreviated as SF₆) is widely used in the electrical industry due to its excellent insulation and arc-extinguishing properties, including in circuit breakers, high-voltage switches, high-voltage transformers, gas-filled composite capacitors, high-voltage transmission lines, and current transformers. Additionally, owing to its chemical inertness, non-toxicity, non-flammability, and non-corrosiveness, SF₆ is extensively employed in metal smelting, atmospheric tracing, electronic manufacturing, and other sectors.
Sulfur hexafluoride is a chemically stable gas with an atmospheric lifetime of approximately 3,200 years. Notably, it exhibits exceptional absorption capacity for infrared radiation, making it a potent greenhouse gas whose potential greenhouse effect, calculated over a 100-year timeframe, is 23,900 times that of CO₂. Moreover, emissions of sulfur hexafluoride into the atmosphere are increasing at a rate of 8.7%.
The extensive use of sulfur hexafluoride-based electrical equipment has inevitably caused pollution and environmental damage to the very ecosystems essential for human survival. The increasing consumption of sulfur hexafluoride in high-voltage electrical systems is exerting growing negative impacts on the environment. Within the global context, other industries utilizing sulfur hexafluoride have made significant strides in reducing its emissions.
Further research should be conducted on the decomposition methods and equipment for sulfur hexafluoride, as well as on the practical applications of its substitutes. Continuous monitoring must be maintained regarding its recovery and reuse to prevent atmospheric emissions. In the short term, simple yet effective measures to reduce sulfur hexafluoride emissions include: minimizing the use of GIS systems, including H-GIS; reducing reliance on dedicated sulfur hexafluoride-containing equipment; and encouraging complete elimination of sulfur hexafluoride usage in medium-pressure equipment.
