Experimental Study on the Effect of H<sub>2</sub> on the Degradation of SF<sub>6</sub> by Pulsed Dielectric Barrier Discharge
Zhaodi Yang, Yalong Li, Yufei Wang, Xiaoxing Zhang, Kun Wan, Ying Zhang
Abstract
Sulfur hexafluoride (SF6) is widely used in high-voltage gas insulation equipment, but SF6 has a strong greenhouse effect, with the “peak carbon dioxide emissions and carbon neutrality” goal proposed, its harmless degradation treatment has become an urgent problem in the power industry. In this article, it is proposed that SF6 degradation under <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> synergy is based on pulsed dielectric barrier discharge (DBD) plasma technology. The results show that <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> can significantly promote the degradation of SF6 and improve its destruction and removal efficiency (DRE). Among them, as the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> concentration increased gradually from 0.2% to 2%, the DRE of SF6 gradually increase. The complete removal of SF6 was achieved by adding 2% <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> at a flow rate of 50 mL/min of 2% SF6 gas mixture and a power input of 55 W. The detection and analysis of SF6 discharge degradation products showed that the main products were SO2, SOF2, SO2F2, SiF4, and OF2. The addition of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> will inhibit the formation of S–O–F gas products, and promote the formation of SO2 and S elements. With the increase of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> concentration, the rate of S element generation gradually accelerated, and the selectivity of SO2 in gas decomposition products reached more than 50% when <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_{{2}}$ </tex-math></inline-formula> concentration was high. The results of this study provide a direction for the efficient degradation and product regulation of SF6.