• 한국환경보건학회지
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• 제23권1호
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• pp.50-54
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• 1997

The removal efficiency of nutrient was investicated by using Glycine max Meer seedling. After budding, Glycine max Merr was raised at darkness for 4 days. During cultivation, the removal efficiency of $NO_2-N+NO_3-N$ was up to 90% with initial concentration of 20-100 ppm. The removal efficiency of PO$_4$-P was up to 80% with initial concentration at 30 ppm, but it was down to 22% and 27% at 40 ppm and 50 ppm. When the removal efficiency of nutrient was compared with alternating 12 hours' light and darkness, the removal efficiency of NO$_2$-N + NO$_3$-N was up to 90% at below 60 ppm. It was not different from each other. But it was particularly low about 62% and 34% at 80 ppm and 100 ppm in alternating 12 hours' light. The removal efficiency of PO$_4$-P was low at alternating 12 hours' light between 10-50 ppm on the whole range. The neutralizing capacity of pH was shown in acidity and alkalinity except strong acidity(below pH 3). The initial pH was neutralized at 6.0-7.7 of pH after 4 days. Particularly, Glycine max Meer seedling that was difference from other water plants, was shown the neutralizing capacity in strong alkalinity.

• 방사성폐기물학회지
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• 제9권3호
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• pp.121-129
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• 2011

전기화학적으로 생성되는 $Ag^{2+}$를 사용하는 MEO 공정에 의한 NO 제거에 전류밀도, $AgNO_3$ 농도, 세정 용액의 유속 및 NO-공기 혼합가스 유속이 미치는 영향을 조사하였다. 전류밀도가 증가할수록 NO의 산화 반응 속도 및 제거 효율이 증가하였으며, 0.1 M 이상의 $AgNO_3$ 농도 조건에서 ㅍ 농도가 NO의 제거 효율에 미치는 영향은 무시할 만 하였다. 세정용액의 유속이 증가할수록 NO의 제거효율은 점진적으로 증가한 반면에 NO-공기 혼합가스의 유속이 증가할수록 NO의 제거효율은 점진적으로 감소하였다. 실험 범위 내에서 도출한 최적조건을 적용한 MEO 공정 및 3 M 질산 흡수 공정을 복합적으로 적용하여 NO-공기 혼합가스를 처리하였으며, NO 및 $NO_x$의 제거 효율은 각각 95% 및 63%를 얻었다.

• 한국농공학회논문집
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• 제62권5호
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• pp.39-46
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• 2020

This study evaluated the nitrogen oxide (NO_x) removal efficiency by air purification concrete blocks with titanium dioxide (TiO₂). The concrete in the mixtures had a 30% water:cement ratio, to which TiO₂ was added at 0%, 5%, and 10% of cement weight. The compressive strength reduction rate and removal efficiency of NO_x were investigated. The result of the compressive strength test in the study indicated that addition rate of TiO₂ did not lead to signifcant effect. In terms of the average removal efficiency of NO_x, mix No. 1 using a TiO₂ mixing ratio of 0% had a removal efficiency of 0.57% on average; thus, the removal effect w as not significant. For the other samples prepared by mixing, the average removal efficiencies for mix No. 2 (5% TiO₂) were 58.86% and 62.05% for normal and washing surface treatments, respectively, and those of sample No. 3 (10% TiO₂) were 59.94% and 67.61%. mixs No. 4 (5%) and No. 5 (10%), in which TiO₂ diluted with distilled water was sprayed onto the block surface, had an average NO_x removal efficiency of 61.72% and 68.48%, respectively. In terms of NOx removal efficiency, Mixs No. 3 and No. 5 with 10% TiO₂ were better than Mixs No. 2 and No. 4 with 5% TiO₂. In addition, analyzing the NO_x removal efficiency results from the fixing method, it was capable to apply mixing (washing) and the diluted spray methods. Therefore, it was found that the diluted spray method applied in this study can be employed in any manufacture of air purification concrete blocks.

• 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.

• 한국대기환경학회지
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• 제19권3호
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• pp.315-323
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• 2003

The goal of this study if the optimization of discharge electrode for pulsed corona discharge reactor located in thermal power plant. For this purpose, we have performed experiments of NO$_{x}$ removal rate by exchange of discharge electrode diameter and arrangement of discharge electrode in the non -thermal plasma reaction facility using a ethylene as additive. If the diameter and numbers of discharge electrode were larger, the NO$_{x}$ removal rate was higher. From these results, if we optimized the shape and installed numbers of discharge electrode at the pilot plant, we could increase the NO$_{x}$ removal rate with less amount of additive than current amount.mount.

• 공업화학
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• 제22권4호
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• pp.433-438
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• 2011

본 연구에서는 SNCR 공정에서 온도, NSR, 산소 농도가 질소산화물 제거 효율에 미치는 영향을 실험과 CHEMKIN-II 프로그램을 사용하여 수치적으로 조사하였다. 산소가 없는 조건에서 NO 제거 효율은 반응기 온도에 따라 증가하였다. 반면 산소농도가 4%일 때, NO 제거 효율은 $900{\sim}950^{\circ}C$에서 최대를 나타내었다. 산소의 존재는 저온에서 NO 제거를 증가시키는 것으로 나타났다. 산소농도와 무관하게 NO 제거 효율은 NSR에 따라 증가하였다. CHEMKIN-II에 의해 예측된 NO 제거 효율의 온도와 NSR-의존성은 실험결과와 유사하였다.

• 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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• 제8권2호
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• pp.1-11
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• 1994

This study was conducted to develop a new RBC process available for the effective removal of organic matters and nitrogen in sewage. The RBC process for the oxidation organic compounds and nitrification was designed to occur at the 1st-stage and next-stage RBC respectively. Then nitrified water was recycled to the denitrifying RBC located at the lower part of the 1st-stage RBC. Some results were summarized as follows. 1. The loading limitation was represented as $60g{\cdot}COD/gm^2/day$ in experiment of simultaneous removal of organic matter and nitrogen. The maxmum COD % removal was 85% at the load $35g{\cdot}COD/m^2/day$. 2. The $NO_3-N$ % removal was approximately 80% at the load $60g{\cdot}COD/m^2/day$ and the maximum $NO_3-N$ remaval rate was $3.9g{\cdot}COD/m^2/day$ and the overall C/N ratio of 11.0 as required to achive 80% of $NO_3-N$% removal. 3.$NO_3-N$ removal rate was rapidly decreased above the load $7g{\cdot}NH_4{^+}-N/m^2/day$ and the maximum $NO_3-N$ removal rate was $3.7g{\cdot}NO_3-N/m^2/day$. 4. Irrespective of the recycle ratio, the COD % removal at the system of 2-stage RBC unit was nearly constant as 89% while the maximum one in the 1st-stage unit was 77% in the case of 50% recycle. 5. The maximum COD % removal in the 3-stage RBC system was 93% while 1st-stage one being 80%, under the $NH_4{^+}-N$ load of $7.4g/m^2{\cdot}d$. Also maximum percentage of nitrification and denitrification was 69% and 41% respectively, under the same $NH_4{^+}-N$ load.

• 대한환경공학회지
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• 제31권1호
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• pp.29-34
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• 2009

표면처리폐수 내 질산성 질소를 제거하기 위한 전기화학적 처리공정에서 전극간격, 환원제, 1단 처리수 반송, 타 물질과 동시 처리 등 네 가지 조건을 변화시키며 실험을 진행하였다. 실험 결과, 전극간격은 10 mm일 때 질산성 질소 제거효율이 높았으며 10 mm 보다 전극간격이 좁아질 경우 농도분극 현상의 증가로 인해 제거효율이 감소하며 10 mm 보다 넓어질 경우 전압이 상승하여 에너지 소모가 증가하였다. 환원제 영향에 대한 실험 결과, 질산성 질소가 환원되는 과정에서 수소가 소모되기 때문에 수소이온 농도가 높은 산성조건에서 더 원활한 환원반응이 이루어졌으며 아연을 1.2배 투입할 경우 질산성 질소와의 반응량이 증가하여 질산성 질소 제거효율이 증가하였다. 1단 처리수를 반송할 경우 난류가 형성되어 환원전극에 부착된 아연이 탈착되어 재 이용되고 내부 확산이 증가하여 농도분극현상이 감소함으로 인해 질산성 질소 제거효율이 증가하였으며 아연 투입량 감소 효과가 나타났다. 암모니아성 질소는 질산성 질소 제거에 영향을 미치지 않았고 폐수 내 염소성분이 충분할 경우 질산성 질소와 동시 처리에도 문제가 없는 것으로 나타났다. 중금속은 환원되는 과정에서 전자를 소모하여 질산성 질소 제거효율은 감소하지만 전류밀도 증가나 본 장치의 전단을 중금속 제거용으로 사용하는 방법 등으로 해결이 가능할 것으로 생각한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1777-1779
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• 2001

In this experiment, an attempt to use the sludge pellets as catalyst for NO removal from simulated gas is experimentally investigated by using cylinder type reactor. An experimental investigation has been conducted for NO concentration of 50[ppm], 100[ppm], 200[ppm] balanced with air. a gas flow rate of 5[1/min]. Cylinder type reactor is at upstream of system for corona discharge and packed bed type reactor filled with sludge pellets ate put at downstream of Cylinder type reactor for catalystic effect. And AC voltage to discharge the gases was supplied. In the result, NO removal with magnetic field is higher than that without magnetic field, when packed-bed reactor with sludge pellet is installed at downstream of cylinder reactor NO, $NO_2$ removal rate increased and $O_3$ is not generated.