• 산업기술연구
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• 제26권A호
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• pp.181-188
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• 2006

In this study, we analyzed the effects of several process variables on the removal efficiencies of NO and $SO_2$ by the dielectric barrier discharge process combined with photocatalysts. The $TiO_2$ photocatalysts were coated onto the spherical-shaped glass beads as dielectric materials by the dip-coating method to analyze the effects of photodegradation reaction on the NO and $SO_2$ removal. As the voltage applied to the plasma reactor increases, or as the pulse frequency of applied voltage increases, the NO and $SO_2$ removal efficiencies increase. Also as the residence time increases, or as the initial concentration of NO decreases, the NO and $SO_2$ removal efficiencies increase. The higher the amount of $TiO_2$ particles coated onto the glass bead is, the larger the surface area of $TiO_2$ particles for the photodegradation reaction is and the NO and $SO_2$ are removed more quickly by the faster photodegradation reactions.

• 청정기술
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• 제13권2호
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• pp.115-121
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• 2007

본 연구에서는 유전체 장벽 방전-광촉매 복합 공정에 의한 NO 및 $SO_2$ 제거를 실험적으로 분석하였다. 유전체 장벽 방전을 위해 유전체로서 유리구가 사용되었고 $TiO_2$ 광촉매 입자는 딥코팅(dip-coating) 방법에 의해 높은 비표면적을 가지는 스펀지 형태로 유리구에 코팅되었다. 플라즈마 반응기에 인가된 전압이나 펄스 주파수, 혹은 기체의 체류시간이 증가함에 따라, NO 및 $SO_2$의 제거효율은 증가하였다. NO 및 $SO_2$ 공급농도 증가하면 NO 및 $SO_2$ 제거에 더 많은 에너지가 요구되어 NO 및$SO_2$의 제거효율이 감소하였다. 본 연구의 실험 결과들은 NO 와 $SO_2$를 제거하기 위한 유전체 장벽 방전-광촉매 복합 공정 설계의 기초 자료로 사용될 수 있다.

• 산업기술연구
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• 제23권A호
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• pp.181-186
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• 2003

In this study, we analyzed $NO_x$ and $SO_x$ removal efficiencies by a pulsed corona discharge process and investigated the effect of several process variables. The removal efficiencies of NO and $SO_2$ were measured changing the process variables of initial concentrations of NO, $H_2O$, and $NH_3$, $SO_2$, applied voltage, pulse frequency and residence time. As the applied voltage or the frequency of applied voltage or the residence time increases, the NO and $SO_2$ removal efficiencies increase. The NO and $SO_2$ removal efficiencies also increase by the addition of $O_2$ or $H_2O$, or by using the large diameter of the discharge electrode. The experimental results can be used as a basis to design the pulsed corona discharge process to remove $NO_x$, $SO_x$ and VOCs.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.129-135
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• 2005

본 연구에서는 펄스 코로나 방전 공정에 의해 $SO_2$와 $SO_2/NO$의 제거효율을 분석하였으며, 여러 공정변수가 제거효율에 끼치는 영향을 체계적으로 조사하였다. 공정변수로서 인가전압, 펄스 주파수, 체류시간, 반응물의 초기 농도(NO, $SO_2$, $NH_3$, $H_2O$, and $O_2$)의 영향을 분석하였다. 인가되는 전압, 펄스 주파수 또는 체류시간이 증가함에 따라 또는 $O_2$와 $H_2O$가 첨가됨에 따라 $SO_2$의 제거효율과 $SO_2/NO$의 동시 제거효율은 증가하였다. 또한, $NH_3$의 초기 농도가 증가할수록 $SO_2/NO$의 제거효율은 증가하였다. 이 실험적인 결과들은 $NO_x$와 $SO_x$를 제거하기 위한 펄스 코로나 방전 공정 장치 설계의 기초 자료로 사용될 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1794-1796
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• 1998

In this study, the $SO_2$ addition effect on NOx removal has been conducted from a combustion flue gases by the do corona discharge-activated radical shower systems. The simulated flue gases were consisted of NO-O_2-$N_2$, NO-$CO_2-N_2-O_2$ and $NO-SO_2-CO_2-Na-O_2$([NO]o:200ppm and $[SO_2]o$:800ppm). The injection gases used as radical source gases were $NH_3$-Ar-air. $SO_2$ and NOx removal efficiency and the other by-products were measured by Fourier Transform Infrared(FTIR) as well as $SO_2$. NOx and $NO_2$ gas detectors. By-product aerosol particles were also observed by Condensation Nucleation Particle Counter(CNPC) and SEM images after sampling. The results showed that asignificant aerosol Particle formation was observed during a removal operation in corona radical shower systems. The NOx removal efficiency significantly increased with increasing applied voltage and $NH_3$ molecule ratio. The $SO_2$ removal efficiency was not significantly effected by applied voltage and slightly increased with increasing $NH_3$ molecule ratio. The NOx removal efficiency for NO-$SO_2-CO_2-N_2-O_2$ was better than that for NO-$CO_2-N_2-O_2$.

• Environmental Engineering Research
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• 제24권3호
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• pp.389-396
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• 2019

The electrical energy consumption (EEC) in removal of NO by a $UV/H_2O_2$ oxidation process was introduced and related to removal efficiency of this gas. The absorption-reaction of NO was conducted in a bubble column reactor in the presence of $SO_2$. The variation in NO removal efficiency was investigated for various process parameters including NO and $SO_2$ inlet concentrations, initial concentration of $H_2O_2$ solution and gas flow rate. EEC values were obtained in these different conditions. The removal efficiency was increased from about 22% to 54.7% when $H_2O_2$ concentration increased from 0.1 to 1.5 M, while EEC decreased by about 70%. However, further increase in $H_2O_2$ concentration, from 1.5 to 2, had no significant effect on NO absorption and EEC. An increase in NO inlet concentration, from 200 to 500 ppm, decreased its removal efficiency by about 10%. However, EEC increased from $2.9{\times}10^{-2}$ to $3.9{\times}10^{-2}kWh/m^3$. Results also revealed that the presence of $SO_2$ had negative effect on NO removal percentage and EEC values. Some experiments were conducted to investigate the effect of $H_2O_2$ solution pH. The changing of pH of oxidation-absorption medium in the ranges between 3 to 10, had positive and negative effects on removal efficiency depending on pH value.

• 대한환경공학회지
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• 제29권1호
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• pp.62-67
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• 2007

본 연구의 목적은 액상 균일질 촉매를 이용하여 연소가스 중에 포함되어 있는 $SO_2/NO$의 동시제거 기술 개발에 있다. 연구는 bench scale/소규모 pilot scale에서 이루어졌으며 연구 결과는 다음과 같다. 1) $SO_2$는 실험조건에 상관없이 높은 제거효율을 가지는 것으로 확인되었다. 그러나 NO의 경우 충진층 높이가 증가할수록, 농도가 낮을수록, 촉매 분사량이 증가할수록 제거효율이 증가하는 것으로 나타났다. 2) Fe(II)-EDTA를 이용한 $SO_2/NO$ 동시처리 기술 개발을 위한 최적의 설계 인자는 충진 높이 =0.5 m, 액체-기체비 = 20 $L/m^3$, 반응기 단수=3단, 반응기 단면적 = 0.025 $m^2$로 결정하였다. 3) 연구 결과를 기초로 $SO_2/NO$의 동시처리 효율을 실험한 결과 각각 95%, 81% 이상 제거가 가능했다. 4) 높은 HTU는 NO의 제거에 있어 유리하지만 과도한 HTU는 스크러버의 운전효율을 감소시키므로 최적의 HTU를 결정하는 것이 필요하다.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.159-166
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• 2014

In recent years, researchers have put a considerable effort to decrease the emission of harmful gaseous pollutants to the atmosphere. In order to remove simultaneously $SO_2$ and $NO_X$ from the flue gas of small and medium-sized ship, we designed minimal wet scrubber inside a compact multistage modular system. In this study we proceed experiment of elemental technology at each stage of the scrubber. The each stage is oxidation of NO which is the main component of $NO_X$, and removal of $SO_2$, respectively. $NaClO_2$ was used to oxidize NO gas, and NaOH was used to remove $SO_2$ gas. The maximum NO conversion efficiency and the $SO_2$ removal efficiency are both indicate 100%.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.468-474
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• 2005

SOx and NOx are known major precursors of acid rain and thus the abatement of their emissions is a major target in air pollution control. To obtain basic data on the removal process of simultaneous $SO_2/NO$, the optimal reaction condition and the composition of reaction solution for simultaneous removal of $SO_2/NO$, ware investigated using a bubble column reactor. Pilot scrubber was consisted of scrubber, filter and control box. Dust removal rate was 83, 92, and 97% with catalyst flux of 0.5, 0.8, 1.5 L/min, respectively Average dust removal efficiency with a kind of nozzle was about 94 and 90% in STS FF6.5 (5/8in.) and 14 of P.P W(1.0in.), respectively Dust and $SO_2$ were removed more than 98-96% regardless of reactor number. In the case of NO gas, removal yield of 83.3% was achieved after 48 hours in 1 stage, also removal yield of 95.7% was reached in 2 stages. In tile case of application of STS (5/8 in.) and P.P (1.0 in.) as used fill packing, removal efficiency was reached higher than 98% without related to of kind of fill packing.

• 상하수도학회지
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• 제22권3호
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• pp.307-314
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• 2008

In this study, the effects of applied voltage, solution pH and coexistence of other ions such as sulfate ion (${SO_4}^{2-}$) and chloride ion ($Cl^-$) were investigated on the removal of nitrate-nitrogen ($NO_3{^-}-N$) from ground water by electrodialysis. The examined operating conditions were evaluated for optimizing the removal efficiency of $NO_3{^-}-N$. Real ground water samples taken from a rural area of Yongin city and artificial ones with components similar to the real ground water were tested for the study, which contained $NO_3{^-}-N$ concentration of 17mg/L that exceeds current drinking water quality standard of 10 mg/L. The increase in the removal rate of $NO_3{^-}-N$ was observed as the applied voltage increased from 5V to 30V, while no significant increase in the removal rate appeared at the applied voltage beyond 20V during a given operating time. The removal rate appeared to get lower at both acidic and basic condition, compared to neutral pH. Coexistence of of ${SO_4}^{2-}$and $Cl^-$ demanded much longer operating time to achieve a given removal rate or to meet a certain level of treated water concentration. When nitrate ion was combined with ${SO_4}^{2-}$and $Cl^-$, the removal rate was reduced by 4.29% and 10.83%, respectively.