Simultaneous Treatment of Various Malodorous Substances in Gas by Non-Thermal Plasma

With the continuous improvement in living standards, odor, a major environmental hazard, has attracted increasing attention. In this study, dielectric barrier discharge technology was used to concurrently remove NH3/H2S components of odorous gas. The NH3/H2S removal rate was analyzed under different gas concentrations, energy density (ED), relative humidity (RH), and other factors, and the O3 generated in the discharge process and the effects of separate and simultaneous NH3/H2S removal were analyzed. At the ED of ~2 J/L, the NH3 and H2S removal rates were 55% and 31%, respectively, when they treated separately, while their removal rates were 95% and 54%, respectively, when they treated together. With increasing RH, the discharge effect of the reactor worsened, resulting in a reduction in the NH3/H2S removal rate: the higher the ED and the lower the gas concentration, the higher the NH3/H2S removal rate. The following proposal could be made: 1) the OH produced during the reaction of H2S/NH3 with O and O3, and the H produced by the decomposition of H2S/NH3 molecules by high-energy electron impact supplement the degradation reaction of another gas, respectively, accelerating the activation and dehydrogenation reaction process of H2S and NH3. At the same time, an alternative path is that hydrogen sulfide reacts with ozone to produce sulfur dioxide, and sulfur dioxide reacts with ammonia to produce sulfate. Sulfate reduces NO2, which is the intermediate product produced during the decomposition of NH3 to N2, improving the removal rate of the two gases and 2) the O3 concentration is higher during mixed removal, speeding up the degradation reaction of NH3/H2S.