Scaling of surface-plasma reactors with a significantly increased energy density for NO conversion
ABSTRACT Comparative studies revealed that surface plasmas developing along a solid-gas interface are significantly more effective and energy efficient for remediation of toxic pollutants in air than conventional plasmas propagating in air. Scaling of the surface plasma reactors to large volumes by operating them in parallel suffers from a serious problem of adverse effects of the space charges generated at the dielectric surfaces of the neighboring discharge chambers. This study revealed that a conductive foil on the cathode potential placed between the dielectric plates as a shield not only decoupled the discharges, but also increased the electrical power deposited in the reactor by a factor of about forty over the electrical power level obtained without shielding and without loss of efficiency for NO removal. The shield had no negative effect on efficiency, which is verified by the fact that the energy costs for 50% NO removal were about 60 eV/molecule and the energy constant, k(E), was about 0.02 L/J in both the shielded and unshielded cases.
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- "A lot of studies have been carried out to investigate NO x removal by an electron-beam NTP-based process . Masuda and Nakao first proposed the electrical NTP process for NO oxidation, and encouraging results have been obtained in both experimental and industrial investigations –. Furthermore, Byun et al. reported effective oxidation of Hg 0 with a dielectric barrier discharge and a pulsed corona discharge reactor –. "
ABSTRACT: The simultaneous removal of NOx, SO2, and Hg from simulated flue gas by a plasma-absorption hybrid system was investigated. In the nonthermal plasma reactor, NO could be effectively oxidized to NO2. However, Hg-0 oxidation was significantly restrained since NO concentration and its reactivity with O-3 are much higher than those of Hg-0. In the absorber, SO2 and NO2 were absorbed by (NH4)(2)SO3 solution, in which the S(IV) ions (SO32- and HSO3-) were found to be dominant for NO2 absorption. The S(IV) ions were significantly oxidized during the absorption, causing an increase in NO2 concentration with operating time. However, the addition of S2O32- inhibited the S(IV) oxidation and promoted the removal of NO2. With a followed electric mist eliminator, the NH3 slipped from the absorber can be captured, and Hg-0 was efficiently oxidized, which can be further removed by water absorption.IEEE Transactions on Plasma Science 02/2013; 41(2):312-318. DOI:10.1109/TPS.2012.2234483 · 0.95 Impact Factor
- Journal of Nanomedicine & Nanotechnology 01/2013; 04(02). DOI:10.4172/2157-7439.1000163 · 5.72 Impact Factor
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ABSTRACT: A sliding surface discharge was formed on a dielectric layer in steam at ~100 °C and atmospheric pressure. The material properties and the thickness of the dielectric layer were found to strongly affect the energy deposition into the plasma. With a 0.32 cm thick dielectric the energy deposition was 1.4 times greater than with a 0.48 cm thick dielectric, and with window glass it was 1.3 times greater than with Macor of the same thickness. Product gases were H2 (73 ± 4%) and O2 (27 ± 1%), and H2O2 accumulated in the condensed water up to 0.4 g l−1. The energy yield for hydrogen was 1.2 ± 0.1 g H2 kWh−1 and independent of the input power and thickness or material of the dielectric. However, for hydrogen peroxide the energy yield, which varied between 0.61 and 3.2 g H2O2 kWh−1, was found to depend strongly on the thickness and material of the dielectric. The addition of benzene to the steam increased the energy efficiency of hydrogen to 2.3 g kWh−1, and decreased oxygen and hydrogen peroxide by about 3 and 6 times, respectively. It also caused the deposition of phenol and polymer-like layers on the dielectric. The results are explained on the basis of reactions of H and OH radicals adsorbed on the surface and/or in gas phase.Journal of Physics D Applied Physics 03/2013; 46(14):145201. DOI:10.1088/0022-3727/46/14/145201 · 2.72 Impact Factor