• Clean Technology
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• v.13 no.2
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• pp.115-121
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• 2007

In this study, we analyzed experimently the NO and $SO_2$ removal by the dielectric barrier discharge-photocatalysts hybrid process. The glass spheres were used as a dielectric material for dielectric barrier discharge and the $TiO_2$ photocatalysts were coated onto those spheres by the dip-coating method. The $TiO_2$ particles were coated in the sponge-shape, which has the larger surface area. As the voltage applied to the plasma reactor, the pulse frequency of applied voltage, or the residence time increases, the NO and $SO_2$ removal efficiencies increase. The increase in the supplied concentrations of NO and $SO_2$ leads to the higher energy for NO and $SO_2$ removal and the NO and $SO_2$ removal efficiencies decrease. These experimental results can be used as a basis to design the dielectric barrier discharge-photocatalysts hybrid process to remove NO and $SO_2$.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.129-135
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• 2005

In this study, we have analyzed the removal efficiencies of $SO_2$ and $SO_2/NO$ by the pulsed corona discharge process and investigated the effects of several process variables on those removal efficiencies systematically. The effects of process variables such as applied voltage, pulse frequency, residence time, and initial concentrations of reactants (NO, $SO_2$, $NH_3$, $H_2O$, and $O_2$) on the removal efficiency were analyzed. As the applied voltage, the pulse frequency or the residence time increases or as the $O_2$ or the $H_2O$ or the $NH_3$ concentration in the inlet feed gas stream increases, the $SO_2$ removal efficiencies and the simultaneous removal efficiencies of $SO_2/NO$ also increase. These experimental results can be used as a basis to design the pulsed corona discharge process to remove $NO_x$ and $SO_x$.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.38-41
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• 1995

화석연료의 연소에 의하여 방출되는 SO$_2$ 와 NO 에 의한 대기오염의 심각성은 이미 잘 알려져 있으며 그에 따른 배출규제 또한 강화되고 있다. 최근에는 탈황과 탈질을 동시에 처리하는 동시 탈황탈질 공정의 연구가 진행되고 있다. 동시제거 공정은 주로 흡수제/촉매를 토대로 개발되고 있으며 산화구리가 담지된 알루미나 (CuO/${\gamma}$-A1$_2$O$_3$) 흡수제/촉매는 SOx, NOx 동시제거에 효과적인 물질로 알려져 있다. 담지된 CuO 와 담체 A1$_2$O$_3$는 SO$_2$ 와 $O_2$ 존재하에 반응하여 CuSO$_4$ 와 $Al_2$(SO$_4$)$_3$ 가되며 [1] CuSO$_4$ 와 미반응된 CuO 는 NO 제거를 위한 촉매로서의 역할을 하게 된다 [2].

• Journal of Energy Engineering
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• v.8 no.1
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• pp.150-158
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• 1999

본 연구는 저온플라즈마를 이용하여 배기가스중의 SOx와 NOx를 동시에 처리하는 공정을 개발하는 것으로서, 최적의 반응제 선정과 효율적인 공정의 구성을 위해 SOx, NOx와 반응제와 반응기구를 밝히고자 하였다. 실험은 1.0 N㎥/h의 모사가스를 이용한 기초실험과 20 N㎥/h의 실제 연소가스를 이용한 실험으로 진행되었으며, 반응제로는 NH3와 파리핀계 및 올레핀계 탄화수소를 사용하였다. NH3를 반응제로 한 SO2 제거반응은 비플라즈마 조건에서는 NH4HSO3, 플라즈마 조건에서는 (NH4)2SO4의 생성반응이었고, 두 조건 모두 높은 제거율을 나타냈다. 반응제를 사용하지 않은 플라즈마 조건에서 SO2는 환원반응이 일어나고 O2 농도의 증가는 역반응을 증가시키는 화학평형에 의해 SO2의 제거율이 감소되었다. 플라즈마 조건에서 NO는 O2농도가 낮은 경우는 NO의 환원반응이 주로 일어나고, O2 농도가 높을 경우는 산화반응이 지배적이었다. 올레핀계 탄화수소는 플라즈마 조건에서 NO 산화 반응에 탁월한 효과를 보였을 뿐만 아니라 SO2 제거에도 효과를 보여 최대 40%의 제거율을 나타냈으며, NH3의 사용을 줄일 수 있음을 확인하였다.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.772-777
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• 2005

Porous hydrated lime and limestone filters were prepared by foaming and gelcasting method, and their physical properties were evaluated. Through these analyses, it has been found that with the increased porosity and pore size of the filters, majority of pores in the filters were inter-connected by windows. Also, $SO_2$ removal efficiency for the filters was investigated. As the porosity and the reaction temperature increased, $SO_2$ removal efficiency also increased. Especially, unlike the variation of entrance concentration, the entrance flow rate had great influence on the removal efficiency. In case of the filters with an equal porosity, the hydrated lime filter had superior removal efficiency compared to the limestone filter. From these results, it was shown that the high conversion ratio to CaO from the hydrated lime filter was a result of facilitated formation of $CaSO_4$ by $SO_2$.

• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.14-21
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• 2006

An experimental apparatus for the removal of $SO_2$ gas using microporous hollow-fiber membrane G-L contactors was setup. Various performance experiments were carried out with commercial membrane modules and the membrane modules made by KIER. The $SO_2$ removal efficiency was outstanding. When the hollow-fiber membrane was used for the removal of $SO_2$, the selection of absorbers and additives, membrane material, operating conditions of membrane manufacture were significant variables to develop optimal G-L contactors. More experiment works will be done for the development of compact, cost-effective and better G-L contactors.

• Fire Science and Engineering
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• v.29 no.4
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• pp.57-60
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• 2015

The removal efficiencies by elastic fire gas mask of toxic gases CO, HCl, HCN, and $SO_2$ produced by a fire have a key role in saving lives. The elastic fire gas mask comprises a visible window, elastic hood, gas purification canister, and air vent. It does not have hair or neck thongs, which makes it easy to use and put on quickly. This research examined the removal efficiency of toxic gases by such a mask. The removal efficiencies for CO with a background concentration of 2505.0 ppm were 99.99 and 99.98% after 3.5 and 8.5 min, respectively. The residual CO concentration was drastically increased after 8.5 min. The removal efficiencies for HCl, HCN, and $SO_2$ with background concentrations of 1003.0, 399.0, and 100.3 ppm, respectively, were 100% after 20 min.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.62-67
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• 2007

It was investigated to develop the technology for simultaneous removal of $SO_2/NO$ in flue gas using liquid homogeneous catalyst. Test was carried out using a bench scale and a pilot scale experiment. The investigation led to the following results: 1) Removal efficiency of $SO_2$ gas showed good results regardless of operating condition. Removal efficiency of NO gas, however, proportionally increased with higher packing height, lower concentration and larger injection rate of catalyst 2) The optimum design parameters for simultaneous removal of $SO_2/NO$ gas using Fe(II)-EDTA catalyst were as follow: HTU(height of transfer unit) = 0.5 m, liquid gas ratio = 20 $L/m^3$, NTU (number of transfer unit) = 3 stages, cross dimension of scrubber=0.025 $m^2$ 3) The removal efficiencies of $SO_2$ and NO were 95% and 81%, repletely. 4) The high HTU is advantageous on removal of the NO, but the excessive HTU diminishes operating efficiency. Consequently, it is important to decide the HTU of optimum.

• Analytical Science and Technology
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• v.15 no.3
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• pp.256-262
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• 2002

After porous filters were manufactured using cordierite powder whose mean paricle size was 200${\mu}m$, they were loaded with catalysts such as $V_2O_5$, CuO and $LaCoO_3$ by vacuum impregnation method. And the NOx/SOx simultaneous removal efficiency was measured by passing NO and $SO_2$ through catalyst-loaded ceramic filters. The cordierite porous filters had the apparent porosity of 61.6%, the compressive strength of 12.3 MPa and the pressure drop of 147 pa at the face velocity of 5 cm/sec. According to the analysis of NO/$SO_2$ simultaneous removal efficiency, perovskite $LaCoO_3$ catalyst was the most efficient for the simultaneous NO and $SO_2$ removal. The $LaCoO_3$ catalyst-loaded filter could remove more than 90% for NO and more than 80% for $SO_2$.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.512-517
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• 2009

$SO_2$ concentrations in oxy-fuel combustion flue gases increases about three times as high as that of conventional air combustion system owing to the flue gas recirculation for the control of combustion temperature. So the desulfurization reaction is different from that of the conventional air combustion system due to exceptionally high $CO_2$ and $SO_2$ concentration. In this study, drop tube furnace(DTF) system was used to investigate the desulfurization characteristics of limestone in oxy-fuel combustion furnace. The experiments were performed under $O_2/CO_2$ atmosphere to examine the effect of operating variables such as reaction temperatures, Ca/S ratios and inlet $SO_2$ concentrations on the $SO_2$ removal efficiencies. $SO_2$ removal efficiency increased with reaction temperature, Ca/S ratio and inlet $SO_2$ concentration. And the addition of water vapor resulted in about 4~6% of increase in $SO_2$ removal efficiency.