• 한국환경과학회지
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• 제12권12호
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• pp.1255-1260
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• 2003

Plasma-photocatalytic oxidation process was applied in the decomposition of Triethylamine(TEA) and Methyl ethyl ketone(MEK). Plasma reactor was made entirely of pyrex glass and consists of 24mm inner diameter, 1,800mm length and discharge electrode of 0.4mm stainless steel. And initial concentrations of TEA and MEK for plasma-photocatalytic oxidation are 100 ppm. Odor gas samples were taken by gas-tight syringe from a glass sampling bulb which was located at reactor inlet and outlet, and TEA and MEK were determined by GC-FID. For plasma process, the decomposition efficiency of TEA and MEK were evaluated by varying different flowrates and decomposition efficiency of TEA and MEK increased considerably with decreasing treatment flowrates. For photocatalytic oxidation process, also the decomposition efficiency of TEA and MEK increased considerably with decreasing treatment flowrates. The decomposition efficiency of MEK was 57.8％, 34.2％, 18.8％ respectively and the decomposition efficiency of TEA was reached all 100％. This result is higher than that of plasma process only, From this study, the results indicate that plasma-photocatalytic oxidation process is ideal for treatment of TEA and MEK.

• 한국환경과학회지
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• 제16권11호
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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.

• 한국가스학회지
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• 제22권2호
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• pp.46-51
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• 2018

산업이 급속하게 발전함에 따라 자연 대기에서 악취를 유발하는 매우 적은 양의 황화수소가 존재합니다. 매립 및 하폐수처리장에서 나오는 황화수소 성분은 대기에 존재하므로 많은 민원이 발생됩니다. 민원이 발생하는 악취가스를 측정하기 위해 $10{\mu}mol/mol$ 농도 수준의 황화수소 인증표준물질(Certified reference material)을 개발하고자 하였다. 질소 안에 $10{\mu}mol/mol$ 수준의 황화수소 가스 제조는 ISO 6142에 의한 중량법을 사용하였다. 4 개의 알루미늄 실린더에 가스 CRM을 제조하고 GC-AED로 그 농도를 확인했습니다. 제조의 불확도는 0.50 % 미만이었고, 제조일치성은 0.22 %이었다. 실린더의 내부 흡착은 1500 psi에서 0.10 %이었고 1 년 동안 장기간 안정한 것으로 평가되었다. 이 황화수소 CRM의 제조 일치성, 실린더의 흡착 및 장기 안정성에 대한 상대 확장불확도는 1.05 %(신뢰도 95 %, k = 2) 이내로 개발되었다.

• KSBB Journal
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• 제25권5호
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• pp.421-428
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• 2010

본 논문은 복합흡수제를 이용하여 유해가스를 처리하기 위해 식물정유의 주요구성성분을 파악한 식물정유로 황화수소가스의 처리효율을 규명하고자 하였다. 또한 복합흡수제와 황화수소가스에 의한 제거반응을 위한 적정조건을 분석하였으며 그 결과는 아래와 같이 요약 할 수 있다. 1) 황화수소가스는 중화반응으로 처리하고 져 할 경우, 식물정유의 화학구조에서 알코올기, 알데히드기, 에스터기 등이 중화반응에 관여한다. 실험결과 앞서 언급한 화학작용기가 포함되어 있는 경우에 아민계열의 2-아미노에탄올 및 식물정유의 복합흡수제와 황화수소 가스와의 중화반응으로 염을 형성하여 유해가스 제거효율이 98%에 도달한다. 2) 황화수소가스를 제거하는 중화반응의 경우에 온도와 pH에 따라 처리효율이 크게 달라졌다. 높은 온도보다는 낮은 온도에서 제거효율이 거의 98%이상 나타났다. 적정 pH는 중성영역에서 비교적 처리효율을 확인하였다. 3) 황화수소가스의 처리효율은 초기농도에 따라 처리효율이 크게 차이가 나타났다. 황화수소의 초기농도가 1,100 ppm 이상인 경우에 처리효율은 40%로 나타났다. 반면, 240 ppm 이상인 경우에는 10분이내에 황화수소 가스 처리 효율이 90%이상 처리되는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권5호
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• pp.690-700
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• 2012

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen ($NH_3$-N) and $H_2S$ gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, $NH_3$-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as $NO_2$, $NO_3$ and $SO_4$ concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that $NH_3$-N, $H_2S$ and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

• 한국환경과학회지
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• 제15권2호
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• pp.133-139
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• 2006

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and NOx compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study was performed to evaluate effect of removal of gaseous NOx using a soil and a yellow soil. Over $60\%\;and\;48\%$ of NOx from a soil and a yellow soil was removed at the inlet NO concentrations of $423\~451$ppb, respectively. The bio-filter using a soil media was capable of purifying NOx with a different natural processes. Although some of the processes are quite complex, they can broadly be summarized as adsorption into soil pore water, and biochemical transformations by soil bacteria. When the filteration bio-reactor was applied to a soil and a yellow soil, effective NOx removal was obtained for several times and months. These results show that a soil biofilter can be of use as an alternative advanced NOx treatment system.

• Asian Journal of Atmospheric Environment
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• 제11권3호
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• pp.139-152
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• 2017

Excessive amounts of volatile organic compounds (VOCs) and odorants discharged into the environment are highly dangerous to human health as well as to ecological systems. Biological treatments of waste gas streams, called biofiltration, containing VOCs and odorous compounds has gained much attention because biofilters are more cost effective and environmentally friendly than conventional air pollution control technologies. This review provides an overview of biotrickling filtration, which is a type of biofiltration including continuous trickled-water flow inside filter media, for VOC and odor abatement. The configuration, design, cost effectiveness, removal capacity and environmental impact of this techniques and the future research and development needs in this area are all considered.

• 한국환경과학회지
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• 제7권5호
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• pp.615-622
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• 1998

생마늘과 김치에서 발생되는 휘발성 유기화합물에 대해 열흡탈착 혹은 퍼지/트랩을 이용한 가스크로마토그래프/질량선택성 검출기법에 의해 분석하였다. 메틸알릴 황, 이메틸 황, 이메틸 이황, 이알릴 황, 이알릴 이황, 메틸알릴 이황, 이알릴 이황 및 이메틸 삼황과 같은 대단히 악취가 강한 성분이 검출되었으며 이들 중 이메틸 이황과 이메틸 삼황은 김치의 숙성과정이나 마늘이 아닌 김치의 재료에서 발생된 것으로 추정되었다. 마늘이나 김치에서 발생되는 악취성분은 우리나라 사람의 입김이나 김치를 보관하는 냉장고 안의 공기 중에서도 검출되었다. 한국인의 입냄새나 냉장고 안의 냄새의 원인은 마늘이나 김치에서 발생되는 이황 화합물이 주성분으로 판단되었다. 이러한 냄새를 없애주는 간단한 방법으로 마늘이나 김치를 열처리하는 것이 대단히 효과가 있음이 밝혀졌다.

• 유기물자원화
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• 제8권1호
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• pp.60-68
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• 2000

바이오필터 기술은 수백 ppmC의 저농도 배가스를 처리하는 데에 있어 효과적이며, 비용이 저렴하고 환경적으로 건전한 처리방법이다. 적용범위로는 폐수처리장, 퇴비화시설, 음식물가공공장에서 발생되는 악취를 비롯하여 매립지가스 및 토양증기추출(SVE, soil vapor extraction)시 발생되는 휘발성 배가스의 처리등이 있다. 바이오필터 기술을 효과적으로 적용하기 위해서는 문헌연구를 꼼꼼하게 실시 한 후 실험실규모, 파일롯트규모, 그리고 현장규모로 점차 확대하여 실시하는 것이 바람직하다. 본고에서는 바이오필터 기술의 원리, 설계인자, 운전조건, 적용사례, 그리고 경제성 평가를 중심으로 고찰하였다.

• 한국농공학회지
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• 제43권4호
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• pp.113-119
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• 2001

Ammonia emissions during composting of hog manure mixed with sawdust were studied in four runs comprising a total of 22 pilot-scale reactor vessels. These four runs extended previous work and both verified and extended the previous conclusions. The pilot-scale vessels were 205 L insulated stainless steel drums that were aerated either continuously (high/low thermostatically controlled fans) or intermittently (5 min high fan 55 min off). Temperature ammonia emissions air flow rates carbon dioxide production and oxygen utilization moisture and dry matter reduction initial and final chemical compositions were measured. Ammonia emissions from the intermittently aerated vessels were only about 50% as great as those from the continuously aerated ones but this was found to be a result more related to total air flow than to aeration technique. All of the data for total result more related to total air flow were fitted with a linear regression line y=0.139x+29.835 where y is ammonia expressed as g of N and x is air flow in kg with $R^2$=0.6808. this general trend indicates that about 50% reduction in ammonia emissions can be achieved with 75% reduction in air flow. For the aeration techniques used the minimum oxygen level in te exhaust gas from the vessels was 5% and this is probably a resonable lower limit constraining air flow reduction. However within this constraint lower air flow now appears to be a technique that can reduce odorous ammonia emissions.