Performance of non-thermal DBD plasma reactor during the removal of hydrogen sulfide

Destruction of hydrogen sulfide using dielectric barrier discharge plasma in a coaxial cylindrical reactor was carried out at atmospheric pressure and room temperature. Three types of DBD reactor were compared in terms of specific energy density (SED), equivalent capacitances of the gap (Cg) and the dielectric barrier (Cd), energy yield (EY), and H2S decomposition. In addition, byproducts during the decomposition of H2S and destruction mechanism were also investigated. SED for all the reactors depended almost linearly on the voltage. In general, Cg decreased with increasing voltage and with the existence of pellet material, while Cd displayed the opposite trend. The removal efficiency of H2S increased substantially with increasing AC frequency and applied voltage. Longer gas residence times also contributed to higher H2S removal efficiency. The choice of pellet material was an important factor influencing the H2S removal. The reactor filled with ceramic Raschig rings had the best H2S removal performance, with an EY of 7.30 g/kWh. The likely main products in the outlet effluent were H2O, SO2, and SO3. (C) 2011 Elsevier B.V. All rights reserved.