• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.89-95
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• 2002

A hybrid De- NOx technique of non-thermal plasma and $NH_3$ SCR process has been investigated to remove NOx from 300 hp marine engine exhaust under the low temperature conditions, i.e. $100-200^{\circ}C$. Fundamental investigation with Diesel-like simulant gas was also conducted. The performance of the present technique has been demonstrated by treating real diesel exhaust gases, in which high contents of soot, water vapor, $SO_2$, NOx, and unburned HC are included. Detailed engineering data for evaluating the feasibility of the technique are provided in the present investigation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.169-172
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• 1999

In this experimental study we Proposed the double dielectric barrier discharge (DDBD) reactor to produce as high an electric field as possible. The experiment are conducted for applied voltage from 15 to 20[tV], flow gas rage at 2[1/min] and pulse rate at 120[pulses/s] and 240[pulses/s]. SPD connection of DDBD which combine the surface discharge with the silence discharge was most effective to reduce the NOx. In the decomposition efficiency per watt, the low pulse rate gave hotter efficiency than that of the high pulse rate. However in DeNOx rate, the high pulse rate gave better performance than that of the low pulse rate. NOx removal rate increased with increasing the applied voltage in all reactors.

• 기계와재료
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• v.13 no.3 s.49
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• pp.102-112
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• 2001

• Clean Technology
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• v.25 no.4
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• pp.324-330
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• 2019

The selective catalytic reduction system is a highly effective technique for the denitrification of the flue gases emitted from the industrial facilities. The distribution of mixing ratio between ammonia and nitrogen oxide at the inlet of the catalyst layers is important to the efficiency of the de-NOx process. In this study, computational analysis tools have been applied to improve the uniformity of NH₃/NO molar ratio by controlling the flow rate of the ammonia injection nozzles according to the distribution pattern of the nitrogen oxide in the inlet flue gas. The root mean square of NH₃/NO molar ratio was chosen as the optimization parameter while the design of experiment was used as the base of the optimization algorithm. As the inlet conditions, four (4) types of flow pattern were simulated; i.e. uniform, parabolic, upper-skewed, and random. The flow rate of the eight nozzles installed in the ammonia injection grid was adjusted to the inlet conditions. In order to solve the two-dimensional, steady, incompressible, and viscous flow fields, the commercial software ANSYS-FLUENT was used with the k-𝜖 turbulence model. The results showed that the improvement of the uniformity ranged between 9.58% and 80.0% according to the inlet flow pattern of the flue gas.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.695-699
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• 2021

In this study, Selective Catalytic Reduction on Diesel Particulate Filter (SDPF) after-treatment system was introduced to simultaneously remove NO_x and Particulate Matters (PM) emitted from trucks and special cargo vehicles using old engine. First, in order to select an Selective Catalytic Reduction (SCR) catalyst for SDPF, the de-NO_x performance of V/TiO₂ and Cu-Zeolite catalysts were compared, and the SCR catalyst characteristics were analyzed through Brunauer Emmett Teller (BET), X-ray Diffraction (XRD) and NH3-TPD (Temperature Programmed Desorption). From the activity test results, the Cu-zeolite catalyst showed the best thermal stability. For optimal coating of SDPF, slurry was prepared according to the target particle size. From the coating stability and back pressure test results of SDPF according to the amount of SCR coating, As a result of comparing coating stability, back pressure, and de-NOx performance by producing A, B, and C samples for each loading amount of the SDPF catalyst, the best results were found in the B sample. The engine dynamometer test was conducted for the optimal SDPF after-treatment system, and the test results satisfied Eu-5 regulations.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.2
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• pp.120-124
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• 2000

In this paper, the effect of magnetic field was measured on NOx(NO+NO2) removal and consumption power for wire-plate plasma reactor with magnetic field applied to electric field vertically. NOx of the simulated diesel engine flue gas were removed by the corona discharge generated by DC, AC and Pulsed voltages in wire-plate reactor. Consumption power increased with discharge voltage. However, when magnetic field was applied to electric field vertically, consumption power slightly decreased. NOx removal rate and arc transition voltage for plasma reactor with magnetic field were higher than those for plasma reactor without magnetic field. Consumption power decreased, however NOx removal significantly increased, when water vapour bubbled by dry air was put into simulated flue gas.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.3
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• pp.247-252
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• 2003

In this paper, we made four types of metal particle $Al_2$O$_3$ barrier reactors with and without dielectric of BaTiO$_3$ between metal particle and $Al_2$O$_3$ barrier to investigate NOx removal characteristic and the effect of dielectric on Nox removal. And Nox removal rate is measured when sludge pellets are put at down stream of plasma reactor. Nox removal rate in the reactor with $Al_2$O$_3$ barrier is much better than that in the reactor without $Al_2$O$_3$ barrier, Nox removal rate is not so good in metal particle-Al$_2$O$_3$ barrier reactor with BaTiO$_3$ between metal particle and $Al_2$O$_3$ barrier, however, Nox removal rate is about 40% in metal particle-Al$_2$O$_3$ barrier reactor with TiO$_2$. The most of NO is conversed to NO$_2$ in these kind of reactor. When sludge pellets are put at down stream of plasma reactor, Nox removal rate is greatly improved up to 90%. It indicates that sludge pellets have great effect on the NO$_2$ removal and the improvement of Nox removal rate, however, dielectric materials between metal particle and $Al_2$O$_3$ barrier have not effect. Organic materials included in sludge may react with NO$_2$ and ozone so that Nox removal rate is greatly improved.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.4
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• pp.487-494
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• 1996

Simultaneous effects of $C_2H_4$ injection and heterogeneous chemical reactions on non-thermal plasma process to remove $SO_2$ and NOx from flue gas were investigated in the present experimental study. The present results showed that 40% of the electrical power can be reduced in $C_2H_4$ injection and heterogeneous chemical reaction are simultaneously included in the non-thermal plasma precess. As an effort to apply the non-thermal plasma technique to practical flue gas treatment system, a wire-plate type reactor which has technically similar geometry of industrial electrostatic precipitators is used instead of other types of reactors, such as wire-cylinder, packed-bed and surface discharge which are inappropriate to industrial application. In the present study, the photo pictures of positive streamer corona taken by ICCD camera, voltage and current oscillograms, and design criteria of a wire-plate type reactor are also shown, which are needed for industrial application of the non-thermal plasma process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.18-24
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• 2018

The policy-making and technological development of eco-friendly automobiles designed to increase their supply is ongoing, but the internal combustion engine still accounts for about 95% of the automobiles in use. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. Natural gas is a clean fuel that emits few air pollutants and has been used mainly as a fuel for city buses. In the long term, we intend to develop a new NGOC/LNT+NGCO/SCR combined system that simultaneously reduces the toxic gases, $CH_4$ and NOx, emitted from CNG buses. The objective of this study is to investigate the characteristics of $de-CH_4/NOx$ according to the ceramic and metal substrates of the SCR (Selective Catalytic Reduction) catalysts mounted downstream of the combined system. The V and Cu-SCR catalysts did not affect the $CH_4$ oxidation reaction, the two NGOC/SCR catalysts each coated with two layers began to oxidize $CH_4$ at $400^{\circ}C$, and the amount of $CH_4$ emitted was reduced to about 20% of its initial value at about $550^{\circ}C$. The two NGOC/SCR catalysts each coated with two layers showed a negative (-) NOx conversion rate above $350^{\circ}C$. The ceramic-based combined system reached LOT50 at $500^{\circ}C$, which was about 20% higher in terms of the $CH_4$ conversion rate than the metal-based combined system, showing that the combined system of NGOC/LNT+Cu-SCR is a suitable combination.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.295-300
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• 2003

In Korea, the emission standards for air pollutants will be more tighten from Jan. 2005. Especially, the new emission standards is focused on the nitrogen oxide. From this trend of standards, nitrogen oxide emission is hot issue in energy fields. Also, we have a new environmental problem, the carbon dioxide emission, which are related to the global warming. To solve the environmental problems, we must define the situation of clean-up technologies level in Korea and decide the direction of R&D for flue gas cleaning technologies. Now, this paper discus briefly on the De-NOx R&D activities and the large scale testing facility for flue gas clean-up technologies in Korea Institute of Energy Research. These discussions are contribute to the increasing of the R&D activities for flue gas clean-up technologies in Korea.