Plasma-assisted abatement of SF₆ in a dielectric barrier discharge reactor: investigation of the effect of packing materials

Abstract

The greenhouse gas hexafluoride (SF6) and its degradation is a research hotspot in the environmental field. In a double-layer dielectric barrier discharge reactor, the degradation process of SF6 was studied when packed in glass beads or γ-Al2O3 pellets as well as with no packing system. The results show that the packing materials changed the physical characteristics of the discharge, increasing the equivalent capacitance and discharge power and leading to the generation of more active particles and high-energy electrons. Additionally, the two packing materials effectively improved the degradation removal efficiency (DRE) and energy yield (EY) of SF6. In the γ-Al2O3 system, 2% SF6 gas obtained a maximum DRE of 85.97% with a 110 W input power and the EY reached 9.17 g kWh−1, far exceeding the case without packing. Moreover, the glass bead packing had no obvious effect on the degradation products, while the packing of γ-Al2O3 particles promoted SO2 production and reduced the formation of SOF2, SO2F2 and SOF4. Meanwhile, in the γ-Al2O3 system, the yield of SO2 increased with increasing input power and some undesirable products such as SO2F2 were reduced. These results show that the addition of suitable packing materials such as γ-Al2O3 pellets can effectively promote the harmless degradation of SF6.

Process optimization of nanosecond pulsed packed‐bed discharge plasma for SF6 degradation based on response surface methodology

“…This trend is consistent with Cui et al, higher degradation efficiency can be obtained as pulsed voltage increases, but more energy will be lost in thermal energy and light energy, which leads to lower energy yield in the degradation process. [ 37 ] Furthermore, the gas flow rate is also considered the key factor affecting the SF 6 degradation process. Figure 7a shows that the degradation efficiency decreased with the increase in gas flow rate.…”

SF 6 catalytic degradation in a γ‐Al 2 O 3 packed bed plasma system: A combined experimental and theoretical study

“…The experimental setup has been described in our previous study [12] and is shown in Figure 1. In this experiment, the discharge frequency is maintained at 8.5-9.0 kHz and input power is controlled within 100 W. We selected argon (Ar) as the background gas for SF 6 dilution due to its promotion effects on the discharge and SF 6 degradation [21].…”

“…In 2019, we studied the influence of the packing material type on SF 6 degradation in a packed bed DBD (PB‐DBD) and found that both glass beads and γ‐Al 2 O 3 pellets could promote the degradation efficiency. Additionally, γ‐Al 2 O 3 packing could change the SF 6 degradation pathway and regulate the product selectivity [12].…”

Plasma-assisted abatement of SF6 in a packed bed plasma reactor: understanding the effect of gas composition

“…As pre-heating temperature increases, some products changed significantly. However, [41] pointed out that the temperature changes below 400 °C would not influence SF 6 degradation. Therefore, the mechanism for the temperature effect on the products is still unknown.…”