• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.72-76
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• 2010

We have developed the bio-electrode measuring the variance of the amount of acetylcholine affected by residual pesticide. The working electrode of the biosensor was made by combination of cobalt phthalocyanine and carbon organic compounds. The biosensors were constructed by screen-printing method. The principle of working electrode is similar to thiocholine sensor. We have fabricated the biosensor using standard screen printing method. Generally, the biosensor made by printing method formed thick film biosensor. When the electrodes were made by electrochemical cells, the generation of current by the addition of enzyme substrate was inhibited by standard solutions of organo-phosphate pesticides. The detection limit of sensor is about 0.5 $\mu{g}/L$ for carbofuran. We could improve the responsibility of the sensor by controlling the cobalt phthalocyanine and thiocholine concentration ratio. Also we have tested the EPN and Chlorpyrifos pesticides and found that the biosensor is applicable to fast determination of residual pesticides.

• Korean Journal of Microbiology
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• v.46 no.1
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• pp.27-32
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• 2010

We used phototrophic bacteria to remove low concentrated organic materials (CODCr), nitrogen and phosphorus. We applied $COD_{Cr}$ 37.3 mg/L, $NH_3-N$ 4.0 mg/L, and $PO_4^{3-}-P$ 1.0 mg/L (C:N:P=100:10:1) in the batch test, and the removal efficiencies were shown as follow: $COD_{Cr}$ 87.4%, $NH_3-N$ 46.3%, $PO_4^{3-}-P$ 79.7%. The aerobic process with mixed phototrophic bacteria, ceramic media, and media KSP01 showed the removal efficiencies of $COD_{Cr}$, $NH_3-N$, and $PO_4^{3-}-P$, each as 72.7% and 79.2%, respectively in the lab-scale reactor. The maximum $PO_4^{3-}-P$ removal efficiency reached 92.6% by adjusting pH. There were three conditions used to remove $NH_3-N$. The highest removal efficiency was 98.5% with 10.2 L/min of aeration in 1-2 reactors, and the result of applying river-water showed the high removal efficiency of $NH_3-N$ (82.8%). Therefore, this purification system may be useful to control nitrogen and phosphorus at low concentration in field.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.367-367
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• 2022

토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. LID 기법은 자연적 기작(mechanisms)과 공정(process)을 이용하여 생태계의 물질순환(물순환 포함)과 에너지 흐름이 원활하도록 조성하는 기법으로, 불투수층면에서 발생되는 강우유출수를 관리 가능하다. LID 시설에는 전처리 시설을 두어 초기 고농도의 입자상 물질을 저감시키고, 강우유출수 저류공간을 통한 유출저감, 첨두유량 등을 저감시킨다. 이러한 전처리 시설에는 유기물질 및 영양소의 생물학적 제거를 위한 미생물 서식공간의 제공 등의 역할을 수행하기 위하여 다양한 여재를 적용하고 있다. 본 연구는 비점오염물질 유입이 LID 기법 전처리 시설 내 여재층의 물리·화학적 및 생물학적 환경을 평가하였다. 3개 시설 모두 100%의 불투수층에서 발생되는 강우유출수를 처리하는 LID 시설을 연구대상으로 선정하였으며, 각각의 전처리 시설에는 자갈, 우드칩, 쇄석 등이 적용되어 있다. 퇴적물의 경우 가장 상부에 존재하는 층으로 퇴적물의 오염물질 농도는 2~10.7배 이상 매우 높게 나타났다. 우드칩의 경우 다른 여재에 비해 높은 함수량과 유기물 함량을 보였으며 이는 우드칩의 수분을 보유하는 능력과 거친 표면공극에 오염물질이 부착되기 때문으로 나타났다. 또한, 같은 무기성 여재인 쇄석과 자갈의 경우 여재 크기의 차이를 보임에도 불구하고 미생물의 군집구성과 함수량의 차이를 보이는 것으로 평가되었다. 유기물의 함량이 낮은 강우유출수의 생물학적 처리능력을 향상시키기 위해서는 유기성 여재가 필요하며, 다공성 무기 멀칭재를 적용하고 하부의 토양은 적정 유기물을 배합하여 질산화 및 탈질화 유도가 가능하도록 설계가 필요한 것으로 분석되었다.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.374-379
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• 2000

To elucidate the degradation mechanisms of organic materials in Lake Paldang, oxygen consuming rates in the water column, high molecular weight (HMW) organic materials and aggregates were analyzed. Also the chlorophyll a concentrations and environmental factors were measured three times in 1999. The concentrations of chlorophyll a ranged $5.5{\sim}14.2\;mg/m^3$ with the highest peak of $57.7\;mg/m^3$ at the surface water in April. Chlorophyll a concentration of aggregates retrieved from traps in 5 m and 20 m depths in May were 2779.5, $9044.8\;mg/m^3$, respectively. Those vlaues were more than 6 times higher compared with other months, and more than 49 times higher than water column chlorophyll a. Oxygen consuming rates of water column were in the narrow range of $0.4{\sim}0.5\;mg\;O_2\;l^{-1}\;day^{-1}$. HMW organic materials were using only small amount of oxygen, $0.01{\sim}0.04\;mg\;O_2\;l^{-1}\;day^{-1}$. The aggregates retrieved from 5 m depth by sediment trap consumed the oxygen in the range of $0.48{\sim}0.69\;mg\;O_2\;l^{-1}\;day^{-1}$, while aggregates collected from 20 m depth, 0.88 to $1.04\;mg\;O_2\;l^{-1}\;day^{-1}$. With these results, the HMW appeared not to be degraded in the water column, instead they seemed to be concentrated and affected the sediment oxygen demand.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.06a
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• pp.99-107
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• 1998

전 세계에서 다양한 환경 매체를 통해 광범위하게 검출되고 있는 대표적 환경오염물질 (environmental pollutants)인 polychlorinated biphenyls(PCBs)의 국내 4대강 주요 하천 저니토양과 모공단 하천수 및 저니토중 오염도를 각 congener별로 또는 총량으로서 GC/MS 를 사용하여 정량하였다. 그 결과 4대강의 주요 지천중 낙동강의 사상공단근처의 저니토에서 총 PCBs가 가장 높은 290.87$\mu\textrm{g}$/kg이었고 한강의 왕숙천도 비교적 높은 221.l1$\mu\textrm{g}$/kg이었다. 모공단 하천수 및 저니토 중 PCBs를 분석한 결과 전 시료에서 검출되었으며 하천수 및저니토에서의 총 PCBs 농도(mean$\pm$S.D.)는 0.1069$\pm$0.0179$\mu\textrm{g}$/L 및 908.80$\pm$462.30$\mu\textrm{g}$/kg였으며, 이때 저니토에서의 농축계수는 0.85$\times$$10^4$였다. 저니토중 총 유기물함량과 저니토중 PCBs 잔류량의 조사에서 서로간 상관관계 (상관계수=0.7084)가 있음을 알 수 있었으나 PCBs 배출원에 의한 영향이 커서 정확한 상관관계를 얻기가 어려웠다. Congener-specific analysis에 의해 하천수 및 저니토 시료에서 공통적으로 검출된 대표적 congener는 52, 95, 101, 99,87, 110, 118, 149, 153, 138, 180 였다. 본 연구결과 하천수에서는 triCBs와 tetraCBs 가 비교적 높은 농도로 검출되었던 반면 저니토에서는 hexaCBs 및 heptaCBs가 다른 poylCBs에 비해 비교적 높은 농도로 검출되었다. 이상의 연구결과를 통해 모공단 하천수 및 저니토가 PCBs에 의해 심하게 오염되어 있음을 알 수 있고 국내의 주요 하천의 경우도 계속적인 모니터링이 필요함을 알 수 있다.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.25-31
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• 2021

In this research, in order to effectively utilize the petroleum residue pitch, it was used as an adsorbent for removal of cesium ion. In this experiment, acid modification (hydrochloric acid, sulfuric acid) treatment was performed on the adsorbent to improve the ability to remove low-concentration cesium ions dissolved in water. As a result, when the reaction was performed with 9 M sulfuric acid at 25 ℃ and for 240 min, the removal efficiencies of 1.0 and 2.5 mg/L cesium ions were 66 and 51%, respectively. In addition, as the adsorption time increased in the batch experiment, the removal capacity of 1.0 and 2.5 mg/L cesium ions was improved, and when the adsorption reached for 32 hr, the removal efficiencies were 72 and 68%, respectively. Also, in order to increase the ability to remove the remaining cesium ions, an experiment was performed by temperature change (25, 37, 49 ℃), and 1.0 and 2.5 mg/L cesium ions contained in water under the operating conditions of 49 ℃ and 32 hr showed removal efficiencies of 90 and 81%, respectively. Consequently, these experimental results were intended to be used as an adsorption technology that can economically treat low-concentration cesium ions contained in water.

• 한국관개배수회지
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• no.43
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• pp.20-24
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• 2010

담수호 및 농업용저수지의 유입수는 일반적으로 다유량 저농도의 특성을 갖고 있으며, 특히 강우시에는 유역의 노면에 집적된 비점오염물질이 넓은 면적에서 폭넓게 유출되어 유입되고 있어 기존의 하수처리공법에서와 같이 한곳에 모아 처리한다는 것은 현실적으로 어려움이 따른다. 넓은 유역을 갖는 수체에 적용될 수 있는 공법은 가급적 유지관리가 용이하고, 특히 호소의 주오염 특성인 부영양화 억제를 위한 질소 인 등의 영양 염류를 효과적으로 제거 할 수 있는 수질정화용 인공습지가 많이 검토되고 있다. 인공습지는 습지의 기능 중 수질정화 기능을 극대화 한 것으로 초기에는 도시하수유출 수의 처리를 위하여 사용되었으며, 점차 유기물의 부하농도가 높은 농업배수(축산 등)에 이용되기 시작 하였다. 강우 유출수, 도시하수, 농업배수, 광산 폐수 등의 점 비점오염물질을 저감하기 위한 수질개선시설로 적용이 점차 늘어나고 있다. 최근에는 강우유출과 같은 유출수의 수질을 관리하기 위한 기법으로 인공습지의 사용이 늘고 있다. 본고에서는 한국농어촌공사에서 수행한 습지관련 연구와 자료수집결과 등을 종합하여 인공습지의 기본적인 설계방안을 제시하고자 하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.169-175
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• 1988

A laboratory experiment was conducted to investigate the effects of pH, organic matters and anion on the adsorption and degradation of surfactant by different soils; Anmi series (limestone region), Gangseo series (alluvial soil). For this study, Alkyl Benzene Sulfonate (ABS ; Sodium Dodecylbenzenesulfonate) was used as a surfactant. The results were as follows: 1. Adsorption of ABS by soils was correlated positively with the equilibrium concentration of ABS in a soil suspension. (Anmi seris : r=0.9855, Gangseo series : r=0.9931). 2. Adsorption rate of ABS by soils was about 70% of the treated concentration ($600{\mu}g$ ABS/g soil) in a range of pH 4 to pH 5, and about 20% for pH 8. 3. Addition of electrolytes increased ABS adsorption by soils in a soil suspension; the higher concentration, the higher adsorption. But the influence among electrolytes was not significant. 4. Adsorption of ABS by soils was not affected by soil organic matter content in this experiment. 5. Degradation rate of ABS in a soil suspension was about 85% at $30^{\circ}C$, and about 10 to 15% at $10^{\circ}C$. Addition of sewage accelerated the degradation rate regardless of temperature and reached about 85% in a week.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.4
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• pp.113-120
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• 2006

Wastewater generated through the food waste recycling process have known high concentration, BOD 20,000~150,000 mg/L, which has to treat to the proper level because of a ban on reclamation. But it is impossible to treat less than 10 days by existing water treatment plant. Ecodays Ltd. is to treat this wastewater during 2~4 days by ER-1, which can simultaneously induce the modified PFR(Plug Flow Reactor) of the oxygen transfer rate, MLVSS concentration, and influent concentration to top from bottom of reactor. We tested the pilot test about low concentration food wastewater(BOD 16,500 mg/L) and high concentration food wastewater(64,431 mg/L) at the food waste recycling plant of H-Gun(20t/d). Hydraulic retention time(HRT) of ER-1 for low concentration food wastewater is 2.5day. In low concentration conditions, ER-1 treatment efficiency is to appear BOD 99%, COD 98%, TN 97%, and TP 96%. While ER-1 process for high concentration food wastewater treatment is composed 2 stages, which are to be HRT 2.5day for law wastewater and HRT 1.5 day for secondary treatment. In high concentration conditions, ER-1 treatment efficiency is to appear BOD 97%, COD 84%, TN 66%, and TP 95%. It is treated without temperature control about high temperature($50^{\circ}C$) to appear low treatment efficiency in high concentration conditions.

• Journal of Wetlands Research
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• v.10 no.3
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• pp.9-26
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• 2008

To clarify the reed (Phragmites australis) stand's effects on the sediment properties and its increasing pattern, breaths of reed stands in 1999 and 2000, and sediment properties - water, salt, organic matter, sulphur, nitrogen, carbon and hydrogen contents - along th depth at the three stands in 2007 were surveyed at Suncheon Bay. Regardless of reed stand, the more distance from the land was long, the more water and salt contents of sediment were high. Organic matter content of sediment was high and increased with the reed biomass at the upper layer but low regardless of biomass at the lower layer. Sulphur content of sediment was higher at old reed stand (0.33%) than at new stand (0.21%) or non-vegetated stand (0.23%). Carbon, nitrogen and hydrogen contents of sediment were similar at three stands in mean values. However, their contents were high at upper layer and low at lower layer in a stand. Therefore, the changing pattern of organic matter content with the depth was similar to but not coincided to the inorganic nutrients' ones. The mean breadth of reed stands increased $2.33{\pm}0.73m$ in 1999 and $3.65{\pm}1.64m$ in 2000. However, the increase of reed stands' breadth a year varied along the direction, year or stands, so that there was not a trend in increasing pattern. It was thought that this increasing pattern made the reed's patch round. The height and density of reed shoot in newly formed stand decreased with the distance from the center of stand. In the newly formed peripheral area of a reed stand, the shoot density was not related with the land (north) or sea (south) direction, however, the shoot height was higher in the sea (south) than in the land (north) direction.