• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.583-587
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• 2007

Corona discharge and ozone generation characteristics of a slit dielectric barrier discharge type wire-plate plasma reactor with a third electrode have been investigated. When a third electrode is installed on a slit of the slit barrier, where an intense corona discharge occurs, it is found that a significantly increased ozone output could be obtained. This, however, indicates that the third electrode can activate the corona discharges both of the discharge wire and the slit of the slit barrier in the plasma reactor. As a result, a thin stainless wire, used as the third electrode has a strong effect to influence the corona discharge of the slit and corona wire, especially to the negative corona discharge. Higher amounts of the output ozone and ozone yield, about 1.27 and 1.29 times for the negative corona discharge, can be obtained with the third electrode, which reveals the effectiveness of the third electrode.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.921-925
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• 2007

Gas removal characteristics of an air clean system, consisted of a filter and a nonthermal discharge plasma reactor with a magnetic field, have been investigated with emphasis on the enhancing gas removal efficiency of the applied magnetic field. It is found that the magnetic field influenced significantly to the corona discharge characteristics, decreasing the corona onset voltage and increasing the corona current. As a result, the proposed air clean system with the magnetic field showed the higher removal efficiency of the gas (e.g., trimethlyamine) than that of without the magnetic field. This would be because the magnetic field applied to the discharge plasma reactor of the air clean system can elevate the corona characteristics, and activate the generation of ozone, thus the removal efficiency of the gas was concurrently enhanced. This reveals that the proposed air clean system with the magnetic field could be used as an effective means of removal an indoor pollutant gas.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.508-513
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• 2000

HANJUNG has developed demonstration plant treating combustion flue gas such as dioxide($SO_2$) and nitrogen oxides(NOx). Before operating this system, we tested the inner airflow characteristic of demonstration plant in the front of plasma reactor field 1 and field 2. The experimental results of $25,000Nm^3/hr$ airflow are compared with the computational results using FLUENT code. It is found that the velocity distribution trends are matched the experimental results with the calculation results. To improve the eccentric airflow in the inlet hood, it is necessary to install the vertical guide vane as well as the horizontal guide vane.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.438-443
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• 2007

Titanium oxide films were deposited by the HCP (hollow cathode plasma) reactor at room temperature. With results of simulation about HCP reactor, the temperature profile is uniform on substrate regardless of the heat generation at cathode. The velocity profile on the surface of substrate is more uniform with increasing the gap between cathode and substrate, and surface roughness was decreased with increasing the gap between cathode and substrate. We could confirm that the composition of oxide increased with RF-power, and the ratio of O to Ti in the films was about 2 : 1 at RF-power of 240 watt and distance between cathode and substrate of 3 cm.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.15-20
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• 1999

Visible light spectrum emitted from $H_2$ plasma in the parallel plate reactor using a commercial electric power are investigated by optical emission spectroscopy. Intensity of visible light is measured as a function of $H_2$ pressure and discharging power, and the intensity is compared with plasma density measured with the probe. As a result, the intensity is affected by plasma density and the plasma density is controlled the $H_2$ pressure and the discharging power.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.54-60
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• 2008

The objective of this study is to obtain the optimal process condition and the maximum decomposition efficiency by measuring the decomposition efficiency, electricity consumption, and voltage in accordance with the change of the process variables such as the frequency, maintaining time period, concentration, electrode material, thickness of the electrode, the number of windings of the electrode, and added materials etc. of the harmful atmospheric contamination gases such as NO, $NO_2$, and $SO_2$ etc. with the plasma which is generated by the discharging of the specially designed and manufactured $TiO_2$ catalysis reactor and SPCP reactor. The decomposition efficiency of the NO, the standard samples, is obtained with the plasma which is being generated by the discharge of the combination effect of the $TiO_2$ catalysis reactor and SPCP reactor with the variation of those process variables such as the frequency of the high voltage generator($5{\sim}50kHz$), maintaining time of the harmful gases($1{\sim}10.5sec$), initial concentration($100{\sim}1,000ppm$), the material of the electrode(W, Cu, Al), the thickness of the electrode(1, 2, 3mm), the number of the windings of the electrode(7, 9, 11turns), basic gases($N_2$, $O_2$, air), and the simulated gas($CO_2$) and the resulting substances are analyzed by utilizing FT-IR & GC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.581-582
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• 2005

In order to apply the discharge plasma processing. to industrial areas, the control of the chemical reaction mechanism is necessary. The hybrid plasma reactor was designed for the effective treatment of wastewater and hazardous volatile organic substances. This plasma reactor was similar to the barrier discharge, and surface discharge on the dielectric surface was propagated to the water surface strongly for the heterogeneous chemical reaction at the interface between the working gas and the water surface. The discharge emission in this discharge reactor was mainly $N_2$ second positive band in the case of $N_2$ or air gas atmosphere, and intensities from OH radicals in Ar gas atmosphere were stronger than in $N_2$ or air gas atmosphere. From this result, it is necessary to apply Ar gas for the effective generation of OH radicals in this plasma reactor.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.149-153
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• 2001

A study on the particle growth in $TEOS/O_2$ plasma was performed, and particle size and its distribution was measured by the electrical aerosol analyzer (EAA), light scattering particle size analyzer and the particle size was also determined by SEM. The effects of process variables such as total gas flow rate, reactor pressure, supplied power and initial reactant concentration on the particle growth were investigated. From the EAA results, the particle size distribution is divided into three groups of the cluster size and the small and large size particles. The particle size distribution measured by the light scattering particle size analyzer becomes bimodal, because the cluster size particles smaller than 20 nm in diameter cannot be detected by the light scattering particle size analyzer. The size of particles measured by the light scattering particle size analyzer is in good agreements with those by the SEM. Also we could understand that the particle formation is very sensitive to the changes of reactor pressure and reactant concentration. As the total gas flow rate increases, the particle size decreases because of the shorter residence time. As the reactor pressure, or the reactant concentration increases, the particle concentration increases and the particles grow more quickly by the faster coagulation between particles.

• Journal of Industrial Technology
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• v.19
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• pp.331-341
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• 1999

We analyzed theoretically the removal efficiency and the particle growth inside the pulse corona discharge reactor to remove $NO_x$ and investigated the effects of process variables such as the NO and $NH_3$ input concentrations. Most of NO is converted into $NO_2$ and $HNO_3$ and the $HNO_3$ reacts with $NH_3$ to form the $NH_4NO_3$ particles. About 6.4% of NO is converted into $HNO_2$ which form the $NH_4NO_2$ particles by reaction with $NH_3$. Some of $NO_2$ follows the reaction pathway to form $NO_3$ and $N_2O_5$. The amount of particles formed inside the reactor is basically determined by the input $NH_3$ concentration. The ratio of NO to $NH_3$ affects the reactor length for particle formation significantly. The higher the input concentrations of NO and $NH_3$ are, the faster the particles grow.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2109-2111
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• 2005

The effect of arc like streamer discharge is investigated on the hydrogen generation in the plasma reactor with multineedle - plate electrode geometry and SDR (Plasma reactor using the surface discharge). An additive of the two type (the saw type and the pellet type) was placed under the water surface to investigate the effect of the water surface conditions. The experimental results are compared in case of the reactor with and without an additive on the water surface. The generation of arc streamer discharge is more powerful with increasing applied voltage in the saw type. The maximum hydrogen Production concentration is about 4300 ppm at 74W in the SDR with additive of the saw type. Also, the Energy yield of the SDR (28990 g/kWh, 4300ppm, 74W) is higher than of the multineedle - plate electrode geometry (20892g/kWh, 3300ppm, 77W).