Experimental study of abatement of SF_6 gas using an atmospheric-pressure oxygen microwave plasma torch

摘要

An atmospheric-pressure microwave oxygen plasma torch (APMPT) is used for abating SF_6 gas. The gas composition is analyzed with a Fourier transformation infrared spectrometer, and the abating effect is evaluated in terms of the destruction removal efficiency (DRE). The variation of SF_6 DRE is investigated with respect to the microwave power, the gas flow rate, SF_6 concentration, and the material and length of discharge tube. It is found that the existence of free-discharge regions in the vicinity of the inner wall of the discharge tube, influenced by the flow rate and microwave power, plays an important role in maintaining a stable discharge and determining the DRE value. The energy efficiency can be improved significantly by using quartz discharge tubes of a suitable length. Meanwhile, the explanations about the variation of DRE and energy efficiency for decomposing SF_6 by APMPT are provided reasonably.