• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.538-555
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• 2012

The purpose of this study was to understand $PM_{2.5}$ chemical characteristics on the Suwon/Yongin area and further to quantitatively estimate $PM_{2.5}$ source contributions. The $PM_{2.5}$ sampling was carried out by a high-volume air sampler at the Kyung Hee University-Global Campus from November, 2010 to October, 2011. The 40 chemical species were then analyzed by using ICP-AES(Ag, Ba, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V and Zn), IC ($Na^+$, $K^+$, $NH_4{^+}$, $Mg^{2+}$, $Ca^{2+}$, $NO_3{^-}$, ${SO_4}^{2-}$ and $Cl^-$), DRI/OGC (OC1, OC2, OC3, OC4, OP, EC1, EC2 and EC3) and GC-FID (acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[a] pyrene, indeno[1,2,3-cd] pyrene, benzo[g,h,i]perylene and dibenzo[a,h,]anthracene). When applying PMF model after performing proper data treatment, a total of 10 sources was identified and their contributions were quantitatively estimated. The average contribution to $PM_{2.5}$ emitted from each source was determined as follows; 26.3% from secondary aerosol source, 15.5% from soil and road dust emission, 15.3% from vehicle emission, 15.3% from illegal biomass burning, 12.2% from incineration, 7.2% from oil combustion source, 4.9% from industrial related source, and finally 3.2% from coal combustion source. In this study we used the ratios of PAHs concentration as markers to double check whether the sources were reasonably classified or not. Finally we provided basic information on the major $PM_{2.5}$ sources in order to improve the air quality in the study area.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.197-197
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• 2010

음식물쓰레기의 삼성분은 수분, 휘발분, 회분이며 이들이 차지하는 비율은 계절, 지역별로 다소 상이하지만 수분 약 80%, 회분3%, 휘발분 17%이다. 음식물쓰레기 전처리과정으로 이물질제거, 탈수공정이 있으며 탈수공정에서 다량의 탈리액이 발생한다. 본 연구에서는 탈리액을 데칸타를 이용하여 1차로 원심분리하여 고.액 분리한 액을 실험대상으로 하였다. 실험대상 탈리액의 물성은 BOD 78,800[mg/l], COD 41,000[mg/l], 부유물질 25,900[mg/l], 총질소 928[mg/l]이었다. 탈리액에는 기름성분(육류, 식용유등), 입자상물질등이 포함되어 있으며 이들은 난분해성 유기물질로, 이를 제거하는데 기존의 처리방법으로 많은 어려움이 있어 주요한 수질오염 발생원이 되고 있다. 예를들면 하수처리장 폭기조 수면에 유막을 형성하여 산소공급을 방해함으로 미생물번식을 방해하는 요인이 된다. 본 연구는 음식물쓰레기 탈리액의 수분, 고형분, 유분으로의 삼상분리에 관한 것이다. 유분은 에멀젼형태로 안정되게 수층에 분산되어 존재한다. 미세기포를 이용한 부상법의 경우 미세기포 표면과 유분의 화학적친화력이 낮아 기포표면에 유분이 잘 부착되지 않으며, 원심분리 방법만으로는 유분 분리효율이 낮고, 추출에 의한 분리시 추출액이 다량 소요되고 처리시간이 길며 추출액 비용이 많이 소요된다. 탈리액을 유분, 슬러지, 수분으로 분리하면 환경오염을 일으키는 주요성분을 신재생에너지 원료로 활용할 수 있다. 유분의 주성분이 동식물성 유지이므로 전처리시 산촉매를 이용 수분과 유리지방산을 제거하고 염기성촉매를 이용하여 전이에스테르화 반응을 거치면 바이오디젤인 FAME과 글리세롤으로 변환하므로 글리세롤을 분리하면 바이오디젤을 얻을 수 있다. 슬러지는 입자상 물질로 착화가 잘 되고 건조하면 발열량이 높으며 중금속등에 오염되지 않아 청정연료로 활용이 가능하다. 실험실에서의 탈리액 삼상분리방법은 다음과 같다. 탈리액 30ml당 추출액으로 노말헥산을 1ml를 가한 다음 플라스크에서 $80^{\circ}C$로 가열 후 방냉한다. 가열중 노말헥산의 손실을 방지하기 위하여 증발가스를 콘덴서에서 응축하여 플라스크로 재순환한다. 탈리액을 플라스크에서 꺼내어 원심분리기 rack에 300-400g씩 병에 각각 넣고 4,000rpm으로 30분간 운전한다. 탈리액은 상부로부터 유분층, 미세입자층, 수층, 슬러지층으로 분리된다. 각 층의 계면에서 2종의 성분이 약간 섞일 수 있다. 유분을 분리한 후 유분층 잔존물과 미세입자층, 수층 상층부의 혼합물을 취하여 50g씩 병에 넣고 3,500rpm으로 10분간 운전한 후 유분을 분리한다. 마지막으로 미세입자층만을 3,500rpm으로 10분간 원심분리한 후 유분을 따로 분리한다. 얻어진 유분은 rotary evaporator에서 $120^{\circ}C$로 가열하여 유분과 노말헥산을 분리하며 분리효율을 제고하기 위하여 감압하에서 운전한다. 분리된 유분의 고위발열량이 9,450[Kcal/kg]이었으며 원소분석 결과 탄소 74.7%, 수소 12.55%, 질소 0.08%, 유황분 0.0003%이었다. 분리된 유분의 양은 계절별로 시료별로 다르며 가을철에는 1.6-1.9%, 여름철은 1.0-1.3%이었다. 분리된 슬러지로부터 Hg, As, Cr, Cd, Pb 중금속 성분이 검출되지 않았으며 수분 2.8%, 휘발분 76.85%, 회분 7.52%, 고정탄소 12.83%이었고 원소분석결과 탄소 45.25%, 수소 7.46%, 질소 5.05%, 산소 34.39%, 유황분 0.33%이었으며 저위발열량은 4,480[Kcal/kg]이었다. 분리된 슬러지 양은 11-19% 이었다.

• Analytical Science and Technology
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• v.10 no.3
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• pp.187-195
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• 1997

Chemically modified electrodes(CMEs) for Ag(I) were constructed by incoporating 1,5,9,13-tetrathiacyclohexadecane([16]-ane-$S_4$) with a conventional carbon-paste mixture composed of graphite powder and nujol oil. Ag(I) ion was chemically deposited onto the surface of the modified electrode with [16]-ane-$S_4$ by immersion of the electrode in the acetate buffer solution(pH=4.5) containing $5.0{\times}10^{-4}M$ Ag(I) ion. And then the electrode deposited with Ag(I) was reduced at -0.3V vs. S.C.E. Well-defined stripping voltammetric peaks could be obtained by scanning the potential to the positive direction. The CME surface was regenerated with exposure to 0.1M $HNO_3$ solution and was reused for the determination of Ag(I) ion. When deposition/measurement/regeneration cycles were 10 times, the response could be reproduced with relative standard deviation of 6.08%. In case of differential pulse stripping voltammetry, the calibration curve for Ag(I) was linear over the range of $5.0{\times}10^{-7}{\sim}1.5{\times}10^{-6}M$. And the detection limit was $2.0{\times}10^{-7}M$. Various ions such as Cd(II), Ni(II), Pb(II), Zn(II), Mn(II), Mg(II), EDTA, and oxalate(II) did not influence the determination of Ag(I) ion, except Cu(II) ion.

• Journal of Animal Environmental Science
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• v.10 no.3
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• pp.163-168
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• 2004

This research was carried out to investigate the moisture evaporation and property change depenging on the composting temperature for the escalator reversing composting system. The system was supported by the Y livestock cooperative composting factory. According to the test, the composting remperature eas varied in the range of $65\~80^{\circ}C$. The water content was de-creased to $75\%$ and became about $60\%$ at the end of the phase. Total nitrogen became $0.58\%$, total phosphoric acid $1.47\%$ and potashium $0.49\%$ at the end of the phase.

• The Journal of Engineering Geology
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• v.13 no.1
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• pp.29-50
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• 2003

Physicochemical Properties of acid mine water of the Chonam-ri Creek and the Sagok-ri Creek in the Kwangyang Au-Ag mine area were determined using geochemical approaches. Metal contamination (Cd, Cu, Pb, Zn) is more serious in the Chonam-ri Creek than in the Sagok-ri Creek. However, the contents of Al and Fe is higher in the Sagok-ri Creek. Such differences between the two creeks probably reflect the abundance and composition of ore minerals. The attenuation processes for acid mine water in both creeks were investigated. In the Chonam-ri Creek, a small retention pond which contains limestone plays an important role in the removal of heavy metals by adsorption or coprecipitation due to increase of pH. The capacity of metal scavenging in this pond depends on the seasonal variation of inflow volume. Reddish yellow precipitates sampled in the Chonam-ri Creek were analyzed by XRD, SEM-EDS, EPMA, and chemical decomposition. The precipitates mainly consist of goethite and are also enriched in Al, Mn, Cu and Zn. This inditates that precipitation of goethite is important for scavenging those trace elements, possibly due to adsorption or coprecipitation. In the Sagok-ri Creek, on the other hand, hydrologic mixing of uncontaminated tributaries results in removal of heavy metals with iron hydroxides precipitation due to the pH increase. The mechanisms proposed for metal attenuation at the confluence between contaminated mine water and uncontaminated tributary water are also explained by the property-property plots.

• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.25-34
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• 1995

A Study on environmental Investigation in Imha Dam for the finding the degree of water quality and heavy metals was carried out at 4 sampling station during the period from August 15, 1993 to May 7, 1994. The results were as follows. 1. The ranges of values of pH for water were st. 1-7.56, st.2-7.77, st.3-7.9, st.4-7,7 on the average. Total average of pH values were 7.56-7.9 2. The ranges of values of DO for water were st.1-8.71($mg/{\ell}$), st.2-8.64($mg/{\ell}$), st.3-10. 25($mg/{\ell}$), st.4-9.01($mg/{\ell}$) on the average. Total average of DO of values were 8.64-10.25($mg/{\ell}$). 3. The ranges of values of BOD for water were st.1-1.1($mg/{\ell}$), st.2-1.0($mg/{\ell}$), st.3-0 86($mg/{\ell}$), st.4-0.99($mg/{\ell}$) on the average. Total average of BOD of values were 0.86-1.1($mg/{\ell}$). 4. The ranges of values of COD for water were st.1-1.12($mg/{\ell}$), st.2-1.4($mg/{\ell}$), st.3-0 98($mg/{\ell}$), st.4-1.46($mg/{\ell}$) on the average. Total average of COD of values were 0.98-1.46($mg/{\ell}$). 5, The ranges of values of T- N for water were st.1-0.36($mg/{\ell}$), st.2-0.49($mg/{\ell}$), st.3-0 23($mg/{\ell}$), st.4-0.83($mg/{\ell}$) on the average. Total average of T-N of values were 0.23-0.83($mg/{\ell}$). 6. The ranges of values of T-P for water were st.1-0.053($mg/{\ell}$), st.2-0.06($mg/{\ell}$), st.3-0.02($mg/{\ell}$), st.4-0.07($mg/{\ell}$) on the average. Total average of T-P of values were 0.02-0.07($mg/{\ell}$). 7. In the E. soli group distribution were counted st.1-1130, st.2-1113, st.3-152.3, st.4-1253 by the MPN test. Total distribution of E. soil group were 152.3-1253. 8. The concentration of heavy metals of Cu, Mn, Pb, Zn were measured st.1-0.59, 0.18, 0 04, 74.6( ${\mu}g/{\ell}$), st.2-0.39,0.29,0.03, 54.3(${\mu}g/{\ell}$), st.3-0.1,0.3, ND, 8(${\mu}g/{\ell}$), st.4-0.96, 0 26,0.23,45.6(${\mu}g/{\ell}$) on the average. Cd, Hg, Cr were not detected in the sampling site.

• Food Science and Preservation
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• v.12 no.6
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• pp.656-661
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• 2005

To develop food additives from pyroligneous liquor, we first examined the physicochemical characteristics of volatile substances. The pH, gravity, acidity, solution tar, and scorched remains in the pyroligneous liquor were 2.50, 1.020, $0.8\%$ $2.31\%$ and $0.008\%$ respectively. The main compounds of pyroligneous liquor were 2,6-dimethoxyphenol (syringol), 2-hydroxy-2-cyclopenten-l-one, 1,2-benzenediol (catechol), phenol, 2 (5H)-furanone, 2-methoxyphenol (guaiacol), 5-hydroxymethyl-2 furancarboxaldehyde were found in organic phase, whereas catechol, 1,4 : 3,6-dianhydro-${\alpha}d$-glucopyranose, cyclopropyl carbinol, 5-hydroxymethyl-2 furancarboxaldehyde in aqueous phase.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.2
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• pp.88-93
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• 2006

To recycle the electric arc furnace (EAF) dust as a ceramic raw materials, the leaching concentrations of heavy metals (Zn, Pb, Cr, Cd) were analysed with various pH and mixing ratios for EAF dust and EAF dust-clay mixtures. The evaporation amounts of the some heavy metals were evaluated by measuring their total concentrations in the sintered bodies of EAF dust-clay mixtures with various mixing ratio and sintering temperature. Toxicity characteristic leaching procedure (TCLP) test was conducted for evaluating the chemical stabilities of the heavy metal elements. Leaching concentrations of heavy metal ions shows minimum leaching concentration at the pH 10. Evaporation amount of heavy metals in the sintered bodies were evaluated for the mixtures of pH 10 depenidng on mixing ratio and sintering temperature. Evaporation of heavy metal components were increased with increasing the sintering temperature and contents of the EAF dust. The evaporation of the heavy metal components in EAF dust was effectively suppressed by increasing the clay content. The leaching concentrations of heavy metal components were decreased with increasing clay content and temperature.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.351-357
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• 2000

This study was carried out to find out characteristics and contamination status of the urban-forest soils. Both topsoil (0-20 cm) and subsoil (40-60 cm) samples were collected from Namsan, Changdeok-palace, Seongjusan and Odaesan (control). The samples were analyzed for physicochemical properties, heavy metal (Cd, Cu, Pb, Zn) and anion $(NO_3\;^-,\;SO_4\;^{2-})$ contents. Soil pH of Odaesan was the highest followed by Namsan, Changdeok-palace and Seongjusan. The anion concentrations of the soil samples were in the order of Namsan, Seongjusan > Changdeok-palace > Odaesan. The relationships between soil pH and the anion concentrations showed highly significant negative correlation, which indicated acidification of soil due to air pollutants such as $NO_3\;^-$ and $SO_4\;^{2-}$ was going on. The heavy metal contents of the soils of urban-forest were higher than those of control. Heavy metal contents in the topsoil were higher than those in the subsoil. Since urban-forest soils were quite vulnerable to acidification and heavy metal accumulation due to chronic exposure to air pollutants such as automobile exhaust, a comprehensive countermeasure not to deteriorate urban-forest ecology must be prepared in the near future.

• Journal of Environmental Impact Assessment
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• v.23 no.2
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• pp.75-87
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• 2014

In order to analyze environmental impact of livestock manure and organic fertilizers, this study investigated livestock-breeding and pollution loads, the status of individual and public livestock manure treatment facilities, and the status of production, supply and components of compost and liquid fertilizers in the Nonsan area. Also, on a trial basis, this study investigated the life cycle of the environmental impact of livestock manure and its organic fertilizers on stream, groundwater, and agricultural soil. The results are as follows. Firstly, were detected the range of $0.13{\sim}1.32{\mu}g/L$ of As, $0.004{\sim}0.467{\mu}g/L$ of Cd and $0.5{\sim}9.2{\mu}g/L$ of Pb as a harmful substances which show lower concentrations than person preservation criteria of water qualities and aquatic ecosystem. However, it is not clear that heavy metals affect environment such as stream, groundwater and agricultural soil. Secondly, this influence could change according to investigation time and treatment efficiency. As were detected large amounts of persistent organic pollutants(e.g. $14.24{\sim}38.47{\mu}g/L$ of acetylsalicylic acid, $1.17{\sim}2.96{\mu}g/L$ of sulfamethazine, and $2.25{\sim}174.09{\mu}g/L$ of sulfathiazole) in effluent from livestock farms and small amounts of sulfathiazole($ND{\sim}1.63{\mu}g/L$) in the stream, it is necessary to monitor POPs at individual and public livestock manure treatment facilities. However, significant environmental impact did not appear at groundwater and agricultural soil in the test area supplied with liquid fertilizers. These results could be applied to investigate the environmental impact of livestock manure through a comprehensive livestock manure management information system.