• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.1
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• pp.51-67
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• 2002

In order to understand behaviors of heavy metals around the artificial Lake Shihwa in the vicinity of Kyunggi Bay in Korea in relation with huge environmental changes due to construction of huge artificial lake, water samples were collected from Lake Shihwa and its tributaries from 1996 to 1998 and analyzed. Due to extreme pollutant discharge from various kinds of anthropogenic sources such as the Banweol and Shihwa Industrial Complexes and cities, the Shihwa and its tributaries have been polluted in waters with various heavy metals. The enrichment factors of particulate heavy metals in water of streams and storm sewers were very high. All of the heavy metals observed in the waters showed relatively high temporal and spatial variations. In surface waters of the lake during the desalination after the dike establishment, spatial distributions of heavy metal concentrations were mainly controlled by various biogeochemical factors as well as input of industrial and municipal wastewaters, while, physical mixing was minor factor Pb and Co showed a strong affinity to particle phase, however the affinity to dissolved phase was dominated in Ni, Cu and Cd. Water quality of the artificial Lake Shihwa has been deteriorated by direct discharge of untreated wastewater and heavy metals have been accumulated in the lake system. Therefore, luther environmental improvement plan should be programmed subsequently.

• Journal of Environmental Impact Assessment
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• v.19 no.4
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• pp.443-452
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• 2010

본 연구에서는 도시지역의 하나인 주거지역에서 배출되는 강우유출수 내에 중금속이 장치형 비점 오염저감시설 중에 하나인 와류형시설에서 제거되는 특성을 파악하고자, 대상 중금속을 Zn으로 삼고 2007년 4월부터 2008년 11월까지 모니터링을 수행하였다. 유출수 모니터링은 와류형 시설의 유입부와 유출부에서 유량과 수질을 각각 시간변화에 따라 측정하였으며, 시설유입부와 유출부, 그리고 시설하부에 쌓인 침전물을 채취하여 침전물 모니터링도 수행하였다. 그 결과, 높은 강우강도에서 발생된 강우유출수는 와류형 시설내에 HRT를 감소시켜 Zn의 제거효율이 낮게 관측되었으며, 특히 HRT가 20분이내의 조건이 될 경우에는 처리효과가 없는 것으로 확인되었다. Zn는 입자성물질과 밀접한 관계를 맺으며 제거되는 특성을 보였으며, 입자성물질이 스크린에 의한 여과 및 침전작용이 일어날 때 입자성물질에 부착되어 거동하는 특성을 보였다. 그 중에 0.075mm 이하의 미세한 입자에 부착된 고농도의 Zn는 제거되지 못하였고, 와류형 시설 후단에 후처리시설로서 저류시설을 두어 충분한 HRT를 제공한 결과, 와류형 시설만을 운전하였을 때와 비교하여 높은 제거특성을 보이게 되었다.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.166-172
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• 1999

Fixed-bed adsorption of metal ions on chitosan bead was studied to remove heavy metal ions in waste water. Chitin was extracted from carb shell and chitosan was prepared by deacetylation of the chitin. The chitosan in bead was used as an adsorbent for heavy metal ions. Freundlich and Langmuir isotherm was determined from the experimental results of equilibrium adsorption for individual metal ion ($Cu^{2+}$, $Co^{2+}$, $Ni^{2+}$) on chitosan bead. Adsorption strength of metal ions decreased in the order of $Cu^{2+}$>$Co^{2+}$>$Ni^{2+}$ ion. Breakthrough curves of single and multicomponent adsorption for metal ions were obtained from the experimental results of fixed-bed adsorption. The breakthrough curves were analyzed by simulation with fixed-bed adsorption equation based on LDFA (linear driving force approximation) adopted LAS (ideal adsorbed solution) theory which can predict multi-component adsorption isotherm from individual adsorption isotherm. The behavior of fixed bed adsorption for single and multi-component system could be nicely simulated by the equation.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.363-373
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• 2013

This study investigates the dispersion and behavior of Au and heavy metals in the water system (soil, AMD and stream sediment) at the abandoned Bonjeong gold mine, based on XRD, aqua regia, sequential extraction, and physico-chemical analyses. The XRD analyses targeted quartz and kaolinite in the mine waste soil and quartz and goethite in stream sediment. The physico-chemical analyses of AMD with increasing distance from water system showed that pH increased from 3.00 to 3.19 and Eh decreased from 450 to 396 mV. The Au content in AMD ranged from 0.68 to 0.97 mg/L upstream, but was not detected downstream. The Au content of stream sediment was 13.76 to 22.85 mg/kg. Sequential extraction from stream sediment revealed 10.84% exchangeable (STEP I), 11.09% carbonates (STEP II), 25.53% Fe-Mn oxides (STEP III), 26.62% organic matter (STEP IV), and 24.61% residual (STEP V).

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.149-149
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• 2023

미세플라스틱은 입자크기가 5 mm 이하인 플라스틱으로 정의되며, 수계로 유입된 미세플라스틱은 내분비계 교란물질로 작용하여 생태계에 환경독성을 유발하고 오염물질을 흡착·운반할 수 있는 독성 물질의 매개체로서 미세플라스틱의 위해성에 대한 우려가 증가하고 있다. 본 연구는 수용액에서 다양한 미세플라스틱의 납(Pb) 흡착특성을 평가하고 미세플라스틱의 비표면적에 따른 흡착 효과를 비교하고자 하였다. 플라스틱 종류 중 HDPE (High-density Polyethylene)와 PVC (Polyvinyl Chloride)를 각각 세 가지 크기(Group 1: 2.5 mm - 1.0 mm, Group 2: 1.0 mm - 0.3 mm, Group 3: < 0.3 mm)로 제조하여 분류하였으며, 미세플라스틱 입자크기의 비표면적은 BET(Brunauer, Emmett, Teller)분석을 통하여 측정하였다. 담수환경 조성을 위해 pH 7로 조절한 Pb 용액의 농도(0, 0.5, 1, 5, 10, 30 mg/L)별 흡착실험을 수행하였으며 실험결과를 3가지 흡착등온식(Langmuir, Freundlich, Sips 모델)을 사용하여 미세플라스틱에서 Pb 흡착 거동을 나타내었다. BET 분석 측정결과, PVC의 경우 Group 3 > Group 2 > Group 1 순으로 PVC의 입자크기가 작을수록 비표면적이 크게 나타났으며, HDPE 비표면적 또한 비슷한 경향을 보였다. HDPE와 PVC에서 Pb의 흡착은 Langmuir 모델(R² > 0.97)과 Freundlich 모델(R² > 0.82)보다 Sips 모델(R² > 0.98)이 흡착 거동을 설명하기에 가장 적합하였다. 최대흡착능(Q_m) 상수는 입자크기가 작아질수록 흡착능이 높아지는 추세를 보였으며, 흡착세기(K_F)와 흡착강도(n^-1)는 각 플라스틱의 Group 3(HDPE K_F = 0.028, PVC K_F = 0.032; HDPE n^-1 = 0.225, PVC n^-1 = 0.547)에서 가장 높게 나타났다. 본 연구를 통해 HDPE와 PVC에서 Pb의 흡착특성은 Sips모델로 설명이 가능했으며, 이에 따라 Pb 흡착과정에 복수의 흡착메커니즘이 작용하고 있음을 유추해볼 수 있었다. 미세플라스틱의 입자크기와 비표면적이 Pb 흡착량에 영향을 미치는 것을 알 수 있었으며, 미세플라스틱이 중금속을 흡착하여 생물체 내로 전이시킬 수 있는 매개체 역할의 가능성을 확인하였다.

• Proceedings of the Korea Forestry Energy Research Society Conference
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• 2011.02a
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• pp.45-48
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• 2011

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.262-262
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• 2002

2001년 12월과 2002년 1월에 걸쳐 조간대 환경에 위치하는 어느 해양사격장 중위에서 일정한 간격으로 표층(<5 cm) 해양퇴적물(총22개소)과 해양생물체(굴; 총10개소)를 샘플링하고, Pb, Cu, Cd, Zn를 위시한 중금속원소의 공간적 농도 분포와 생흡수도(bioavailability)를 분석 고찰하였다. 본 논문에서는 예비 연구 결과를 간단히 소개한다. 해양퇴적물에 대한 전함량 분석, 0.1N HCl에 의한 부분 분석 및 BCR법에 의한 연속추출 분석 결과는 다음과 같다. Pb, Cu, Cd, Zn을 위시한 중금속은 대체적으로 점오염원인 사격장으로 갈수록 전함량 및 부분함량이 높아지는 경향을 보여주었다. 사격장 주변에서 가장 중요한 오염물질로 알려져 있는 Pb는 오염원 주변에서만 높은 함량을 보여주어, 해양 환경 하에서 이동도( 및 생흡수도)가 비교적 낮은 것으로 나타났다. 반면, Cu, Cd, Zn의 경우에는 보다 넓은 영역에 걸쳐 퇴적물 내의 부화(enrichment)가 인지되어 연구지역의 갯벌 환경에 의미있는 정도로 영향을 미치고 있는 것으로 나타났다. 이 곳의 생물체(굴) 역시 Pb에 대해서는 낮은 흡수도(-값의 생농축계수)를 나타낸 반면, Cu, Cd, Zn에 대해서는 의미있는 생흡수도를 나타내었다. BCR 연속추출법에 의한 퇴적물 중금속의 존재형태 해석 결과를 보면, fraction 1(F1; exchangeable+acidic phase) 및 fraction 2(F2; reducible phase)의 기여도가 지배적이고, 또한 오염원으로 갈수록 그 기여도는 점차 증가됨을 나타내었다. 특이하게도 유기물과의 친화력이 높은 것으로 알려진 Cu 역시 F1과 F2에 대하여 높은 함량을 나타내어 오염원으로부터의 Cu의 확산을 지시하였다. 외국에 비하여, 그동안 국내에서는 사격장 주변의 자연환경변화에 관하여 연구된 결과가 거의 전무하였다. 본 연구 결과는, 이와 유사한 사격장 주변 환경에서의 중금속 분포와 거동 특성에 대하여 종합적인 모니터링(즉, 체계적인 환경지구화학적 조사ㆍ연구)이 시급함을 시사해 주고 있다.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.149-157
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• 2000

This paper presents the first results of dissolved arsenic in the Kangnung Namdae stream. The distribution of As concentrations measured in 28 August (high water flow) and in 21 November 1997 (low water flow) differs from those of other metals measured during the same period; The concentrations of Doam-dam are lower than those of Obong-dam and accumulation in the downstream in the period of low water flow is not pronounced. The As concentration in the downstream under the low water flow is lower than under high water flow, reciprocally to other metals. Freshwater concentrations are comparable with those measured in pristine river and lower than the world average and the diffrence of concentrations measured during two period is minute. Therefore, the As concentrations in the Namdae stream are background level and the source of As contamination does not exist. In the mixing zone between the freshwater and Donghae seawater, As behave conservatively, indicating the absence of any significant removal or mobilization processes. A first estimation of total dissolved As input from Namdae stream to Donghae coastal sea shows 65.12 kg/yr.

• Economic and Environmental Geology
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• v.56 no.3
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• pp.229-238
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• 2023

Bentonite is a type of rock that has been used as a traditional mineral medicine. It has a variety of pharmacological activities, and is used in traditional Korean medicine to treat jaundice, diarrhea, and hemostasis. In modern medicine, it is used as a raw material and additive for medicines such as antacids, gastrointestinal protective agents, and laxatives. Bentonite produced in Korea was produced through diagenesis or hydrothermal alteration of tertiary volcanic debris distributed in the Pohang and Gyeongju areas. It is mainly used for industrial purposes such as papermaking, paint, civil engineering, casting, and animal feed. Recently, technology is being developed to use it in cosmetics and pharmaceuticals. In this study, the geochemical characteristics of bentonite were identified by analyzing the main components and trace elements of 40 and 21 types of bentonite produced in the Gampo Gyeongju and Yeonil Pohang area. Also it were classifed by formation envrionment of bentonite deposits in the Gampo and Yeonil. As a result of the study, bentonite from the reserch area may be cased by argillic alteraton that alkali elements are removed form basaltic rocks by hydrothermal fluids and AI-CCPI alteration indices wrere also indentified argillic alteraton. It was found that there is a correlation between the behavior characteristics of heavy metal elements (P b, Cr, As) and the hydrothermal alteration of bentonite in the reserch area.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1146-1152
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• 2005

Graft copolymers were synthesized from methylcellulose(MC) and acrylic acid(AA) with active carboxyl groups in the presence of potassium persulfate($K_2S_2O_8$) initiator to enhance adsorption capacity of toxic heavy metal such as $Pb^{2+}$ and $Cu^{2+}$ from wastewater. The resulting grafted copolymers(MC-g-AA/PAA) were mixture of the graft copolymers from MC and AA(MC-g-AA) and polyacrylic acid homopolymers(PAA). The degree of palling was increased with rising concentration of monomer and initiator under the reaction conditions at $60^{\circ}C$, 3 hrs. The water insoluble property of MC-g-AA showed more than 19.7% degree of grafting. So that it could be an adsorbent of heavy metals. Adsorption characteristics of the MC-g-AA were evaluated depending on the degree of grading, pH of wastewater, adsorption time, dosage of MC-g-AA and concentration of heavy metals in the different conditions. Degree of grafting, and initial concentration of heavy metal ions increased, the adsorption amount of $Pb^{2+}$ and $Cu^{2+}$ increased, but added MC-g-AA increased, the adsorption amount per unit weight of $Pb^{2+}$ and $Cu^{2+}$ decreased. The MC-g-AA showed the high $Pb^{2+}$ and $Cu^{2+}$ adsorption amount in the range pH $4{\sim}6$. Also all of $Pb^{2+}$ and $Cu^{2+}$ ions reached in adsorption equilibrium in neighborhood 4 hours. The adsorption of heavy metals described by Freundlich isotherm, it was determined the value of l/n of $Pb^{2+}$ and $Cu^{2+}$ that 0.4294 and 0.3453, respectively.