Wire-tube DBD reactor for H₂S treatment: optimization of geometric and electrical parameters

Based on the wire-tube DBD reactor, this paper studied the effects of different discharge lengths, discharge air gaps, and electrical parameters on the discharge characteristics of the DBD discharge module. The results show that under the condition of increasing applied voltage, different discharge lengths, discharge air gaps, thicknesses of the insulating medium, and equivalent capacitance of insulating medium all show an increasing trend, while the equivalent capacitance of air-gap medium fluctuated within a certain range. When the discharge length was 30 cm, the discharge air gap was 2 mm, and the thickness of the insulating medium was 1 mm, the discharge effect was the best. In terms of electrical parameters, with the increase of the applied voltage, the "burr" of the current waveform increased, the load voltage and discharge power also increased, the discharge air gap voltage remained almost unchanged, and the equivalent capacitance value of the insulating medium continued to increase while the equivalent capacitance of the air gap medium remained almost unchanged. The optimized DBD discharge module was used for the treatment of exhaust gas containing H₂S. The results show that when the gas flow rate was 80 L·h^-1, the initial concentration was 50 mg·m^-3, and the applied voltage was 65 V, the removal efficiency could reach 100% in 4 s. The energy efficiency analysis of the DBD discharge module shows that the energy efficiency of the discharge module varies by changing the different parameters; in the case of H₂S degradation, the end products were mainly SO₂ and SO₃.