Scaling of surface-plasma reactors with a significantly increased energy density for NO conversion. J Hazard Mater 209-210:293-298

Frank Reidy Research Center for Bioelectrics, Old Dominion University, 4211 Monarch Way, Suite 300, Norfolk, VA 23508, USA.
Journal of hazardous materials (Impact Factor: 4.53). 03/2012; 209-210:293-8. DOI: 10.1016/j.jhazmat.2012.01.024
Source: PubMed


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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    • "Located at the exit end of the reactor, the ground electrode was extended to form a conductive shield at the dielectric layer opposite to the discharge area where the PAA is released. This enhanced the electric field in the discharge gap, and a higher energy density was achieved compared to other non-thermal plasma reactors (Malik et al., 2012). "
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    Biotechnology and Bioengineering 06/2015; 112(12). DOI:10.1002/bit.25660 · 4.13 Impact Factor
    • "When multiple electrode assemblies were stacked and operated in parallel, the energy per pulse was found to be the product of the number of reactors times the energy of a single reactor. Obviously , the shielding due to the conducting layers between the reactors [16] or coupling of positive streamers with negative streamers on the same electrode assembly causes a complete decoupling of the reactors. This decoupling allows scaling of the reactors in a compact configuration with high throughput – an advantage in the use of such reactors for commercial applications. "
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    The Chemical Engineering Journal 11/2014; 256:222–229. DOI:10.1016/j.cej.2014.07.003 · 4.32 Impact Factor
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    • "A lot of studies have been carried out to investigate NO x removal by an electron-beam NTP-based process [8]. Masuda and Nakao first proposed the electrical NTP process for NO oxidation, and encouraging results have been obtained in both experimental and industrial investigations [9]–[13]. Furthermore, Byun et al. reported effective oxidation of Hg 0 with a dielectric barrier discharge and a pulsed corona discharge reactor [14]–[16]. "
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    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.
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