• Proceedings of the Korea Air Pollution Research Association Conference
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• 1992.10a
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• pp.14-16
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• 1992

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.05a
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• pp.55-58
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• 1997

대기오염의 주요원인은 소각로 연소가스와 자동차의 배기가스로 이들 이동 오염원에서 배출되는 오염가스는 일산화탄소, 탄화수소, 질소 및 황산화물 둥이고 이들은 공기중의 산소와 반응하여 광화학반응을하여 오존을 생성하며 기타 미세먼지, 수분과 반응하여 스모그를 생성하여 인체의 호흡기 계통 질병을 유발케한다. (중략)

• Journal of the korean Society of Automotive Engineers
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• v.12 no.1
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• pp.10-19
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• 1990

본 기고에서는 농도분석에 사용되는 많은 측정장비 중에서 여러가지의 가스성분을 한번에 측정할 수 있고, 다른 전용가스분석기에 비하여 경제적인 가스크로마토그라프를 소개하고, 특히 탄화수소(hydrocarbon)계열의 연료를 사용하는 열기관의 배기가스분석에 국한하여, 적용예와 문제점을 검토하여 가장 최적의 가스크로마토그라프 운용조건을 찾는데 도움이 되고자 한다.

• Clean Technology
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• v.16 no.3
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• pp.198-205
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• 2010

Two sets of thermal reaction experiment for chlorinated hydrocarbons were performed using an isothermal tubular-flow reactor in order to investigate thermal decomposition, including product distribution of chlorinated hydrocarbons. The effects of $H_2$ or Ar as the reaction atmosphere on the thermal decomposition and product distribution for dichloromethane($CH_2Cl_2$) was examined. The experimental results showed that higher conversion of $CH_2Cl_2$ was obtained under $H_2$ atmosphere than under Ar atmosphere. This phenomenon indicates that reactive-gas $H_2$ reaction atmosphere was found to accelerate $CH_2Cl_2$ decomposition. The $H_2$ plays a key role in acceleration of $CH_2Cl_2$ decomposition and formation of dechlorinated light hydrocarbons, while reducing PAH and soot formation through hydrodechlorination process. It was also observed that $CH_3Cl,\;CH_4,\;C_2H_6,\;C_2H_4$ and HCl in $CH_2Cl_2/H_2$ reaction system were the major products with some minor products including chloroethylenes. The $CH_2Cl_2$/Ar reaction system gives poor carbon material balance above reaction temperature of $750^{\circ}C$. Chloroethylenes and soot were found to be the major products and small amounts of $CH_3Cl$ and $C_2H_2$ were formed above $750^{\circ}C$ in $CH_2Cl_2$/Ar. The thermal decomposition reactions of chloroform($CHCl_3$) with argon reaction atmosphere in the absence or the presence of $CH_4$ were carried out using the same tubular flow reactor. The slower $CH_3Cl$ decay occurred when $CH_4$ was added to $CH_3Cl$/Ar reaction system. This is because :$CCl_2$ diradicals that had been produced from $CHCl_3$ unimolecular dissociation reacted with $CH_4$. It appears that the added $CH_4$ worked as the :$CCl_2$ scavenger in the $CHCl_3$ decomposition process. The product distributions for $CHCl_3$ pyrolysis under argon bath gas were distinctly different for the two cases: one with $CH_4$ and the other without $CH_4$. The important pyrolytic reaction pathways to describe the important features of reagent decay and intermediate product distributions, based upon thermochemistry and kinetic principles, were proposed in this study.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.1
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• pp.34-39
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• 2017

The recent gradual increase in the energy demand is mostly met by fossil fuel, but the research on and development of new alternative energy sources is drawing much attention due to the limited fossil fuel supply and the greenhouse gas problem. This paper assesses the feasibility of producing fuel energy from a dewatered sewage sludge by microwave-induced pyrolysis with sludge char and graphite receptor. Both receptors produced gas, char, and tar in order from product amount. The gas produced for the sludge char receptor contained mainly hydrogen and methane with a small amount of light hydrocarbons. The graphite receptor generated higher gravimetric tar and generated higher light tar. Through the results, the product gas from the microwave processes of wet sewage sludge might be possible as a fuel energy. But the product gas has to be removed the condensable PAH tars.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.4
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• pp.86-94
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• 2015

Torrefaction is a thermochemical process proceeded at the temperature around $250^{\circ}C$ in an inert gas condition. By torrefaction, the hemicellulose portions contained in biomass are broken down to change into the volatile gas which is removed from biomass eventually. The main purpose of biomass torrefaction is to improve the energy density of the biomass to minimize the transport energy consumption, though the flammability can be elevated for transportation. In this study two types of solid biomass fuel, waste wood and rice straw, were torrefied at various temperature range from $200^{\circ}C$ to $300^{\circ}C$ to evaluate the torrefied biomass characteristics. In addition torrefied biomass were tested to evaluate the combustion characteristics using TGA (Thermogravimetric Analysis). After the torrefaction of biomass, the C/H (carbon to hydrogen ratio) and C/O (carbon to oxygen ratio) were measured for aquisition of bio-stability as well as combustion pattern. Generally C/H ratio implies the soot formation during combustion, and the C/O ratio for bio-stability. By torrefaction temperature at $300^{\circ}C$, C/H ratio and C/O ratio were increased by two times for C/H and three times for C/O. The torrefied biomass showed similar TGA pattern to coal compared to pure biomass; that is, less mass decrease at lower temperature range for torrefied biomass than the pure biomass.

• Korean Journal of Microbiology
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• v.46 no.1
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• pp.109-111
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• 2010

Recent studies have described various microorganisms that can degrade PAH, however, there are currently limited methods available to screen for PAH-degrading microorganisms. To screen for PAH-degrading microorganisms, a sublimation method (Alley, Jeremy F. and Lewis R. Brown. 2000. Appl. Environ. Microbiol. 66, 439-442) was modified to produce a simple screening system. In our results, there were several bacterial species capable of pyrene degradation including genera, Coryenbacterium, Gordonia, Rhodococcus, and Streptomyces, which have been screened from 350 bacterial isolates of commercial gasoline and oil-spilled sediment by the sublimation method. The main advantage of this method is that it (i) safely deposits an even, thin and visible layer of PAH onto the agar surface without the use of solvents and (ii) the quantity of PAH sublimed onto the agar can be easily controlled. Overall, this sublimation method may be an effective and simple technique to screen for PAH-degrading microorganisms.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.355-360
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• 1998

Reduction activity of precious metal-loaded HZSM-5 for NO has been studied and was compared to that of Cu-HZSM-5 in the presence of excess oxygen. It was found that among the catalysts used in this study, Ru-HZSM-5 was the most active catalyst for the reduction of NO to $N_2$ in the absence of hydrocarbon reductant. The highest conversion obtained was 45%. No severe inhibition of water vapor to the reduction was observed. It is suggested that the higher catalytic activity of Ru-HZSM-5 may result from the better ability to oxidize NO to $NO_2$ in the presence of excess oxygen. A proposed reaction mechanism for the reduction of NO to $N_2$ in the presence of excess oxygen is that NO is oxidized to $NO_2$ on the surface of Ru-HZSM-5 catalyst and the adsorbed $NO_2$ on the surface is then decomposed to $N_2$. $NO_2$ is supposed to the reaction.

• Journal of Life Science
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• v.21 no.11
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• pp.1511-1517
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• 2011

We isolated a potent phenanthrene-degrading bacterium from oil-contaminated soils of Suzhou, China, and assessed the potential use of these bacteria for bioremediation of soils contaminated by polycyclic aromatic hydrocarbons (PAHs) in a microcosm. Based on 16S rDNA sequencing, we identified this bacteria as Sphigobacterium sp. SW-09. By PCR amplification, we also identified catechol 2,3-dioxygenase genes (nahH genes) mediating PAH degradation. Staphylococcus sp. KW-07, which has been identified in our previous study, showed potential for use in bioremediation of oil-contaminated soils. In this experiment, we compared the rate of phenanthrene-degradation between Staphylococcus sp. KW-07 and Sphingobacterium sp. SW-09 in a microcosm condition. Newly isolated Sphingobacterium sp. SW-09 showed a higher phenanthrene-degradation rate than that of Staphylococcus sp. KW-07 in soil microcosms. Together, our results suggest that the Sphingobacterim sp. SW-09 strain isolated from the Suzhou area may also be useful in bioremediation of PAH-contaminated soils.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.408-412
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• 2003

The purpose of this study was to evaluate the Influence of oil concentration and inoculum size on petroleum biodegradation in soil by Nocardia sp. H17-1, isolated from oil-contaminated soil. To investigate the effect of initial oil concentration on total petroleum hydrocarbon (TPH) degradation, the soil was artificially contaminated with 10, 50 or 100 g of Arabian light oil per kg of soil, respectively. After 50 days, Nocardia sp. H17-1 degraded 78,94 and 53% of the each initial TPH concentration, respectively. Also, it produced 1.35, 4.21, and 5.91 mmol of $CO_2$ per g of soil, respectively. The degradation rate constant (k) of TPH was decreased in proportion to the initial oil concentrations while $CO_2$ production was increased with the concentration. The growth of Nocardia sp. H17-1 was remarkably inhibited when it was inoculated into soil containing 100 g of oil per kg of soil. To evaluate the effect of the inoculum size, the soil was artificially contaminated with 50 g of Arabian light oil per kg of soil, and inoculated with $3${\times}$10^{6}$ , $5${\times}$10^{7}$ , $2${\times}$10^{8}$ cells per g of soil, respectively. After 50 days, the degradation of TPH was remained with similar in all treatment but degradation rate constant (k) and evolved $CO_2$ was increased with increasing the inoculum size.