Experimental Study on the Effect of H2 on the Degradation of SF6 by Pulsed Dielectric Barrier Discharge

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 H-2 synergy is based on pulsed dielectric barrier discharge (DBD) plasma technology. The results show that H-2 can significantly promote the degradation of SF6 and improve its destruction and removal efficiency (DRE). Among them, as the H-2 concentration increased gradually from 0.2% to 2%, the DRE of SF6 gradually increase. The complete removal of SF6 was achieved by adding 2% H-2 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 H-2 will inhibit the formation of S-O-F gas products, and promote the formation of SO2 and S elements. With the increase of H-2 concentration, the rate of S element generation gradually accelerated, and the selectivity of SO2 in gas decomposition products reached more than 50% when H-2 concentration was high. The results of this study provide a direction for the efficient degradation and product regulation of SF6.