• Journal of the Korean Applied Science and Technology
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• v.28 no.4
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• pp.379-385
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• 2011

One of main catalysts for De-NOx in SCR is a $V_2O_5/TiO_2$, and this work formulated powdery catalysts focusing ultimately on corrugate catalytic support. The prepared catalyst consisted of anatase $TiO_2$. Amount of the added vanadium oxide determined the viscosity of catalyst slurry, which is important for washcoat for a final corrugate type catalytic reactor. The test showed a proportional relation between adsorption amount of ammonia and specific surface area. De-NOx efficiency could be obtained up to 96.3 % at $400^{\circ}C$ with a spacial velocity of $4,000hr^{-1}$.

• 기계와재료
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• v.24 no.2
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• pp.72-78
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• 2012

환경오염 문제로 인하여 질소산화물의 규제가 크게 강화되었으며 규제에 대응을 위한 연구가 활발히 진행되면 배기가스 후처리 기술 중의 SCR시스템이 연구되고 있다. 이러한 시스템의 개발에 있어 엔진 거동에 대한 NOx 제거효율을 높이고 장비가격을 낮추기 위하여 정확한 농도 측정이 필요하며, 이러한 측정에 들어가는 감시물질을 이용한 가스센서 방식의 반도체 감지 재료를 이용한 방식, SAW(surface acoustic wave)소자를 이용한 구동 방식, Micro / Nano 공진자를 이용한 방식과 광학방식을 이용한 가스센서의 적외선 흡광 방식, 광음향 방식의 기술소개 및 시장동향에 대하여 간략히 기술한다.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.671-674
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• 2003

Generally, $TiO_2$ powders absorb ultraviolet rays and make oxidation/reduction reactions on its surface. Hydroxide radical(OH), a product of photocatalyst reactions, has so strong oxidation/reduction electric potential that it can oxidize noxious gas like NOx. In this study, $TiO_2$ was substituted for cement to investigate the purifying degree of NOx. Rutile and anatase types of $TiO_2$ were used as photocatalyst. The sun rays and the ultraviolet were used as a light source. Anatase type $TiO_2$ was better than rutile type in purifying performance. The sunray showed the best purifying performance among the light sources. 3% substitution of TiO$_2$ with the sunray was enough to purify NOx efficiently.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.715-719
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• 2000

It is reported that we are facing the serious environment pollution difficulties such as acid rain, green house effects, etc. The gaseous matter CO, NOx, SOx, VOCs which are regarded as main factors for these current pollutions are mainly emitted from power plants and vehicles. Therefore several leading countries are regulating the related laws strictly, especially exhaust emissions from a Diesel engine without an after treatment device. The Objective of this study is to find out NOx removal characteristics focused on emissions of a Diesel engine using radical at each engine speed and load. It is generated from outer air and put into a mixing chamber in the end of exhaust line. In addition, the optimum temperature condition to activate reaction by radical is experimentally carried out. Concentration of exhaust emissions is analyzed from the gas anlayzer(KaneMay) and FTIR to estimate by-products.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1782-1784
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• 1998

The effect of magnetic field was measured on NOx removal for cylinderical-wire plasma reactor with magnetic field applied to electric field vertically. Consumption power increased with increasing discharge voltage. When magnetic field was applied to electric field vertically, consumption power decreased NOx removal rate of plasma reactor with magnetic field were higher, 10-15%, than that of plsama reactor without magnetic field. And NOx removal rate decreased with increasing gas flow rate.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.385-388
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• 2005

In this study, the objective is to develope environment friendship mineral pigments for removal of harmful chemical substance. Environment friendship mineral pigments made of Slag blast furnace-photocatalyst carriers were developed to identify their removal effects of NOx, HCHO and VOCs(benzene, Toluene) on sunlight, fluorescent light and UV lamp. In case of NOx at UV light, the eliminative ability was been better than different harmful materials, and it was appeared large degree rather than different harmful materials.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1247-1255
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• 2007

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and $NO_X$ compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study investigated the optimal mixture fraction of briquet ash, compost, soil and loess for $NO_X$ degradation. Extreme vertices design was used to examine the role of four components on $NO_X$ degradation. Under our experimental conditions, 74.5% of $NO_X$ degradation was observed, using a model mixture(25% briquet ash, 10% compost, 30% soil and 40% loess) containing 100 ppb of NO. It was shown that experimental design analysis could allow selecting optimal conditions in such biodegradation processes in this study.

• Proceedings of the KIEE Conference
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• 2002.06a
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• pp.64-66
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• 2002

This study is to develop electromagnetic plasma reactors for indoor air purification, Removal effect of nitrogen oxide using magnetic field are investigated. And AC or DC high voltage is applied for corona discharge, flow rates are 150${\sim}$1500${\ell}$/min and NO initial concentration is about 10 ppm. In the results, NOx removal rate by AC power is about 10 % higher than that by DC power under the experimental condition of 700 ${\ell}$/min, 5 magnets. When magnet is applied to the reactor, NOx removal rate increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.130-131
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• 2020

This study manufactured the porous foamed concrete granules coated with TiO₂ Nanoparticles, to widen the specific surface area. The Removal rate of concrete granules coated with TiO₂ Nanoparticles was average 56.7%, which was approximately 2.3 time higher than that of the conventional surface TiO₂ coating.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.211-216
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• 2000

In this paper, experimental investigations were carried out to remove NOx, SOx simultaneously from a simulated combustion flue gas [$NO(0.02%)-SO_2(0.08%)-CO_2-Air-N_2$] by using a pulse corona induced plasma chemical processing. Discharge domain of wire-cylindrical plasma reactor was separated from a gas flow duct to avoid unstable discharge by aerosol particle deposited on discharge electrode and grounded electrode. The NOx, SOx removal was experimentally investigated by a reaction induced to ammonium nitrate, ammonium sulfate using a low price of aqueous NaOH solution and a small quantity of ammonia. Volume percentage of aqueous NaOH solution used was 20% and $N_2$ flow rate was $2.5{\ell}/min$ for bubbling aqueous NaOH solution. Ammonia gas(l4.82%) balanced by argon was diluted by air and was introduced to a main simulated flue gas duct through $NH_3$ injection system which was in downstream of reactor. The $NH_3$ molecular ratio(MR) was determined based on [$NH_3$] and [$NO+SO_2$]. MR is 1.5. The NOx removal rates increased in the order of DC, AC and pulse, but SOx removal rates was not significantly effected by source of electricity. The NOx removal rate slightly decreased with increasing initial concentration. but SOx removal rate was not significantly affected by initial concentration. The NOx, SOx removal rates decreased with increasing gas flow rate.