Back to
ICESP VII CONFERENCE PAPER ABSTRACTS PP-4 SERIES

Held in Kyongju, Korea
September 20-25. 1998

The International Conference on Electrostatic Precipitation (ICESP) is the official conference of the International Society for Electrostatic Precipitation (ISESP).  

The following is a list of the Abstracts for the PP-4 Series papers from the VII ICESP Conference.  

PP16 Studies of SO2 Conversion in Discharge with a Dielectric Barrier at an Alternating Polarity Form of the Impulse Voltage
V.I. Perevodchikov, V.A. Fedorov,, E.F. Prozorov, K.N. Uljanov
The Russian Federation State Centre

Abstract
Efficiency of SO2 conversion in a stream of mixture of SO2 with air was studied experimentally.  A discharge was provoked in a reactor composing of dielectric-covered metallic plates with metallic strings stretched between them.  Reactor was applied with a 100 Hz alternating polarity impulse voltage.  Each impulse was a non-symmetric voltage wave including a number of positive and negative semiwaves.  A discharge was excited at the first positive voltage semiwave.  Burning of the discharge occurred for two subsequest semiwaves.  During the first negative and the second positive semiwaves an alternating polarity current was practically in phase with the voltage.  Energy contribution into discharge took place at the first positive, the first negative and the second positive semiwaves.  Current and voltage oscillograms were recorded.  Gas stream parameters (velocity, temperature, mixture composition before and after action) were controlled SO2 content was charged from 150 to 750 ppm, maximum specific energy contribution attained 16 Wh/nm3.  Experimental studies showed conversion of SO2 to 95% of the initial concentration and determined efficiency of the conversion as a function of energy contribution and initial concentration of SO2.  With this method of discharge excitation the presence of a dielectric barrier on one of the electrodes and capability of changing the envelope of the voltage impulse and number of positive and negative semiwaves permit to obtain additional means of improvement of the conversion efficiency. The implemented experiments indicate prospects of the given method of SO2 conversion to get a required concentration of SO3 to carry out gas conditioning prior to the electric precipitator.

To View Paper in PDF Format Click Here   
To go Back to ICESP Paper Page Click Here

PP17 Non-thermal Plasma Processing of Flue Gas with Catalytic Reactions and Water Vapor
Kazuo Shimizu, Toshiyuki Hirano, and Tetsuji Oda
Department of Electrical Engineering, The University of Tokyo

Abstract
NOx removal enhancement from flue gas by using non-thermal plasma processing combined with a catalyst was studied.  Catalysts tested in this paper were copper-coated zeolite, conventional 3-way catalysts.  The combined process of the catalyst reactor and the non-thermal plasma reactor was examined experimentally.  Water vapor from 5 to 15% was added in the flue gas to simulate real exhaust gas condition.

With 5% of water vapor, the best removal rate of about 80% was obtained with Na-ZSM-5 catalyst at 200-300oC without non-thermal plasma.  Combined with non-thermal plasma and water vapor improves NOx removal rate with NA-ZSM-5 at higher temperature.  Such high removal rate was caused by chemical reactions and absorption by the catalyst.  While non-thermal plasma degrades NOx removal rate with Cu-ZSM-5, when the gas temperature of 300oC or above.  When the gas temperature was 100oC, the non-thermal plasma process is enhanced by the combination of non-thermal plasma and catalyst.  The catalyst does not work at such low temperature.

Gas temperature of around 300 or 400oC, 3-way catalyst does not require non-thermal plasma to remove about 70% of NO.

Absorption characteristics was also investigated and only Na-ZSM-5 showed higher absorption characteristics compared to that of Cu-ZSM-5 or 3-way catalyst.

To View Paper in PDF Format Click Here   
To go Back to ICESP Paper Page Click Here

PP18 Dynamic Behavior of the Corona Discharge in Air
Sung-Taek Chun
Division of Physics, Eulji Medical College
Jong-Sik Kim and Gon-Ho Kim
Department of Physics, Hanyang University

Abstract
The spatial and temporal behavior of pulsed corona discharge produced in a coaxial wire-cylinder type reactor has been investigated theoretically.  The model plasma is produced at atmospheric pressure by applying high voltage pulses to a thin center wire of the reactor.  A self-consistent one dimensional fluid model is used to analyze the formation and evolution of the corona; the ion and electron densities, the potential profiles in the discharge region in the reactor are obtained, and the characteristics of the propagation of ionization front are analyzed.  It has been shown that the non-neutral space charges produced by the opposite movements of ions and electrons can induce electric field sufficient to cancel the externally applied electric field inside the bulk discharge region. The dynamics of electrons near the ionization front modifies the electric field, and it is shown to be responsible for the propagation of the ionization front.  The numerical study indicates that the characteristics of the discharge plasma depends strongly on the characteristics of input voltage pulses and the reactor geometry.

To View Paper in PDF Format Click Here   
To go Back to ICESP Paper Page Click Here

PP19 Negative Ion Chemistry of Air Cleaning Coaxial Wire-Tube Electrostatic Precipitators
J.S. Chang and A.L.C. Kwan
Department of Engineering Physics
McMaster University

 

Abstract
In this work, a negative dc corona discharge chemistry in a coaxial wire-tube electrostatic precipitator is numerically simulated. The purpose of this work is to try to gain a better fundamental understanding of the corona discharge chemical process.  In this model, the continuity equations and the charged (or neutral) particle transport equations are solved simultaneously with the Poissonís equations.  One hundred and ninety-five chemical reactions for 38 different chemical species are included.  These species can be divided into three groups.  The first group is the negative ions which include O-, O2-, O3-, O4-, NO-, NO2-, NO3-, N2O2-, and N2O3-.  The second group is the neutral species which include O, O2, O3, N, N2, NO, NO2, N2O, NO3, N2O4, and N2O5.  The third group is the positive ions which include O+, O2+, O4+, O6+, N+ N2+, N3+, N4+, NO+, NO2+, NO3+, NO4+, N2O+, N2O2+, N2O3+, N2O4+, N3O+ and N4O2+.  The simulation results show that the concentrations of neutral radicals and ions (both positive and negative) increase with increasing applied voltage.  In all the simulations, the negative ion with the highest concentration is N2O2-, while the radical with the highest concentration is N2O.  For the positive ion, the species with the highest concentration is N3O+ at the lower applied voltage and N2O3+ at the higher applied voltage.  Also several toxic byproducts like O3, NO, NO2, N2O4, and N2O5 are observed in the simulation results.  However, their maximum computed concentrations are within the acceptable limits.  

To View Paper in PDF Format Click Here   
To go Back to ICESP Paper Page Click Here

PP20 The Modeling of the Removal of NOx/SO2 and VOC from Exhauast Gases By Pulse Corona and Barrier Discharges
Ravil H. Amirov and Elena A. Filimonova
Russian Acadamey of Sciences

Abstract
The effect of pulse corona and barrier discharges on the NOx, SO2, VOC concentrations and ozone synthesis in air has been studied.  A numerical model for in homogeneous gas flow has been developed.  The spatial non-uniformity of gas parameters associated with existence of many streamer channels in discharge chamber is taken into account.  The results of comparison the experimental investigations and the simulations on an approximate mathematical model for the plasma cleaning of air are presented.

To View Paper in PDF Format Click Here   
To go Back to ICESP Paper Page Click Here



][

Last updated: January 16, 2010.
Copyright © 1999 TRK Engineering Services, Inc. All rights reserved.
For more information contact: TRK Engineering Services - 95 Clarks Farm Road - Carlisle, MA 01741 - Telephone: 978-287-0550 - Fax: 978-287-0569 - email: trkeng@apcnetwork.com