Recent progresses, challenges and proposals on SF6 emission reduction approaches

Abstract

The increasing utilization and emission of sulfur hexafluoride (SF₆) pose severe threats to the climate and the environment, owing to its potent greenhouse gas properties. In this paper, we comprehensively review the recent progresses of SF₆ emission reduction approaches. Currently, the use and emission of SF₆ are still on the rise, and mainly concentrated in the power industry. Restrictive use and emission reduction policies are fundamental step in guiding SF₆ emission, but they are poor promoted in developing economies. More specific policies and regulations are needed in conjunction with timely and accurate assessments of SF₆ atmospheric properties and emissions. SF₆ recovery is the direct emission reduction approach, but defects in recovery methods and equipment limit its applications. The development of SF₆ purification technologies and optimizations in recovery devices and processes are needed for its treatment of different regions and SF₆ volumes. SF₆ degradation is the final step of waste gas treatment, and its development needs to better balance the degradation rate and product selectivity, as well as to improve their multi-scenario responsiveness. SF₆ substitution is a necessity for future large-scale SF₆ emission reduction. Improvements in SF₆-free applications and its long-term stability are critical via new gas design, gas mixture optimization and equipment updates. Finally, all the emission reduction approaches are closely related, and promoting their synergistic development and complementarity is the ultimate way to realize SF₆ lifecycle management.

Keywords: Eco-friendly insulating gas; Emission reduction; Harmless disposal; Net-zero; Sulfur hexafluoride.