• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.292-296
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• 2003

Autoclaving처리를 하지 않은 키토산과 autoclaving처리한 키토산과의 중금속 흡착실험을 해 본 결과 다음과 같은 결과를 도출 할 수 있었다. 1) 먼저 중금속간의 흡착능을 고찰하기 위하여 Langmuir와 Freundlich 흉착등온식에 적용시켜 본 결과 Freundlich 흡착등온식 보다는 Langmuir 흡착등온식이 보다 적합한 것으로 나타났다. 2) 시간에 따라서 autoclaving 처리한 키토산의 중금속 제거 가능성과 그 효율을 검토하기 위하여 각 중금속간의 Langmuir 흡착등온식을 이용하여 $q_{max}$를 나타냈다. 15 min > 60 min > 0 min 순으로 모든 중금속 제거 실험에서 15 min 동안 autoclaving 처리한 키토산의 중금속 흡착량이 가장 높은 것으로 나왔다. 그러므로 기존의 키토산 보다는 15 min동안 autoclaving 처리한 키토산이 중금속 제거에 더 좋은 흡착제로써 역할을 할 수 있을 것으로 판단된다. 3) 키토산을 이용한 중금속 제거에서는 $Pb^{2+}$ > $Cd^{2+}$ > $Cu^{2+}$ > $Cr^{3+}$순서로 제거가 되었다. 여러 연구자들의 실험 결과를 종합해 볼 때 Pb$^{2+}$가 중금속 중에 제거가 잘 된다는 연구 결과가 많이 발표 되었으며, $Cd^{2+}$, $Cu^{2+}$, $Cr^{3+}$의 경우에는 흡착제의 종류에 따라서 제거되는 순서가 다르다는 연구 결과들이 보고 되고 있다. 그러나 어떠한 이유로 중금속의 제거에 차이가 있는지에 대해서는 명확한 결론이 내려져 있지 않는 실정이다. 이러한 중금속간의 경쟁적인 관계에 대해 더 많은 세밀한 연구가 이루어져야 할 것 같다.는 0.52mg/$\ell$~0.99mg/$\ell$~의 범위이었다. 신천에 금호강물을 혼합한 이후에도 부유물질, 생화학적산소요구량, 암모니아태 질소, 총인 등의 농도가 개선되지 않았다. 즉 금호강물의 혼합은 신천수질환경사업소에서 배출되는 방류수에 함유되어 있을 2차 오염물질의 희석이라는 이점외의 수질개선효과는 확인되지 않았다.l years and a new type of transfer crane has been developed. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplified model, the simulation was performed and the results could be confirmed by the experiments under various conditions.뢰, 결속 등 다차원의 개념에 대한 심도 깊은 연구와 최근 제기되고 있는 이론

• Journal of the Korea Convergence Society
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• v.7 no.1
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• pp.155-160
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• 2016

The convergence process utilized both leaching and ion exchange techniques has been investigated for the heavy metals removal in the abandoned mine of Chungyang Province, Korea. The contaminated soil samples by heavy metals from Samkwang mine were analysed by statistical analyses. The highly contaminated soils was initially separated by the flotation process. The selectivity indices were increased with increasing flotation reagents. The selectivity of separation was then improved by the use of both leaching and ion exchange processes in order to extract the heavy metals. The results of this study showed that the higher the sulfuric acid concentration, the leaching rate of heavy metals was increased. The lecheate then was removed by the ion exchange method. The anticipating results might imply that convergence process utilized both leaching and ion exchange techniques would somehow apply for the removal of heavy metals in the abandoned mine.

• Journal of the Korean GEO-environmental Society
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• v.3 no.1
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• pp.37-45
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• 2002

EDTA-enhanced electrokinetic removal of copper and zinc from contaminated sandy soil was carried out. In desorption equilibrium tests, the required mass ratio of EDTA to metal was 10:1 to obtain over 90% of desorption from soil. The removal of heavy metals with chelating agent EDTA below pH 3 was limited because of EDTA precipitation. In electrokinetic experiments, the pH control at anode chamber was essential and 38% Cu and 56% Zn were removed under 30 mA for 1.5 days. Heavy metal removal was greatly improved by controlling anode and soil pH with circulation of anolyte with NaOH solution, in which >50% heavy metal was removed for 4 days and >70% for 9 days.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.195-200
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• 2000

Chitin과 탈아세틸화된 chitosan은 중금속 제거에 효과적인 생물흡착제로 잘 알려져 있다. 그러나 본 연구의 결과 crab shell에 있어서의 중금속 제거효율이 순수 chitin과 chitosan에서 보다 더 뛰어남을 알 수가 있었다. 납, 카드뮴, 망간이온 제거실험에서 crab shell은 초기 2시간 이내에 모두 제거되었으나, chitin과 chitosan의 흡착 실험에선 14시간이 경과되어도 이들 중금속의 대부분 수용액 내에서 거의 제거되지 않았다. 구리의 경우 염의 형태에 따른 흡착의 영향을 chitosan에선 제거된 량이 Cu($SO_{4})_{2}$ > Cu($NO_{3})_{2}$ > Cu($Cl_{2}$)의 순으로 나타났으나 chitin에선 모두 흡착이 거의 안된 상태로 나타났다. 주사현미경 분석 결과 crab shell의 표면에 납이 축적되어 있는 상태를 확인하였다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.413-416
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• 2004

매립장 침출수로 인해 오염된 매립장 주변 지하수 정화를 위한 실내실험을 실시하였다. 오염물로는 대표적 염화용제인 TCE와 PCE, 그리고 중금속인 As, Cd, Cr, Pb에 대하여 Air-sparging, 오존 산화법, 화학적 처리방법에 의한 정화효율 실험을 실시하였다. Air-sparging은 TCE, PCE에서 높은 제거효율을 가졌으며, 오존 산화법은 Cr, Pb에서 제거 효율이 좋았다. 반응제를 첨가한 공침방법의 경우, 모든 중금속에 대하여 소석회 첨가시 매우 높은 제거효율을 보였으며, As는 황산제일철에서, Cd, Cr, Pb는 탄산칼슘과 제올라이트 첨가시 높은 제거효율을 나타내었다. 실험결과로부터, 유기오염물과 중금속이 혼합되어 나타나는 매립장 주변 오염 지하수의 경우 휘발성 유기오염물의 제거를 위해서는 폭기방법이, 중금속의 경우에는 공침방법에 의해 수산화물, 탄산염으로 만들어 고형물로 처리하는 방법이 제거효과가 좋은 것으로 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.6 no.4
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• pp.29-42
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• 1986

This study is an experimental research on the adsorption capacity and the adsorption system utilizing Discarded Automotive Tires(DAT) and Powdered or Granular Activated Carbon(PAC or GAC) for the removal of heavy metals, Ag(I), Cd(II), Cu(II), Zn(II). Batch shaking test was conducted to determine the adsorption capacity of DA T and PAC in removing the heavy metals from aqueous wastes; and laboratory-scale column experiment was performed to present design factors affecting the optimum design of adsorption column with DAT and GAC, through the concept of Bed Deph/Service Time(BDST). As results, DAT has been proven to be a good adsorbent will its adsorption capacity not falling behind PAC or GAC. Factors affecting heavy metals removals were amount of adsorbents, initial concentrations, pH and so on. BDST equations were compared with values presented by the breakthrough data from adsorption system.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.15-24
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• 2014

This study was performed to investigate the removal characteristics of heavy metals in Acid Mine Drainage (AMD) using pellet-type Zeolite-StarFish ceramics (ZSF ceramics), in which natural zeolite and starfish were mixed and calcined with wood flour. Kinetic experiment showed the removal reaction of heavy metals by ZSF ceramics reached the equilibrium status within 3 hours. The optimal calcination temperature range for removal of heavy metals was measured to be $800{\sim}1,000^{\circ}C$. The calcination time had little effect on the removal of heavy metal in AMD. The adequate dose of ceramics was shown to be 1.0~1.2 % for removal of heavy metals in AMD. High removal efficiencies of heavy metals (Al, As, Cd, Cu, Fe, Mn, Zn) in AMD, more than 95 % except for Pb, were obtained under the condition of dose of ceramics more than 1.0 %. The removal efficiencies of heavy metals increased with increasing mixing concentration of wood flour. The adequate mixing concentration of wood flour was observed to be 10 %. The batch experimental results exhibited that the ZSF ceramics could act as an efficient ceramics for removal of heavy metals in AMD and the wood flour could provide porous ZSF ceramics with enhanced removal efficiency of heavy metals.

• Journal of the Korean GEO-environmental Society
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• v.3 no.4
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• pp.5-10
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• 2002

Pistia stratiotes(Water Lettuce) can be applied to remove inorganic pollutants from the wastewater for the advanced treatment. This study attempts to remove heavy metals from the secondary treated wastewater. Three different initial concentrations of heavy metals were applied as 0.5, 1.0 and 1.5 mg/L for Lead(Pb) and Chromium(Cr(VI)). In addition, the removal efficiency for the mixture of Lead and Chromium was also observed. The removal efficiency of Pb was in the range of 41.0~72.0% for Pb and it was in the range of 25.0~30.0% for Cr(VI) by Pistia stratiotes. The plants placed in static systems were able to remove the heavy metals in a few days of exposure. However, it was observed that the heavy metals affected produce phytotoxic effects on plants resulting in inhibition of chlorophyl synthesis, decrease in biomass production, and finally plant necrosis. The removal efficiencies of Pb and Cr(VI) by Pistia stratiotes were increased with plant growth.

• Journal of the Korean GEO-environmental Society
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• v.7 no.4
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• pp.5-13
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• 2006

This study was conducted to evaluate the application of $UV/TiO_2/H_2O_2$ process for treating humic acid and heavy metals in surface water. Removal efficiency of $UV/TiO_2/H_2O_2$ process was much more efficient than that of $UV/TiO_2$ process for humic acid and heavy metals removal. The removal rate of humic acid and heavy metals increased with the increase of $TiO_2$ dosage and UV intensity, however decreased with more than 0.3 g/L of $TiO_2$ dosage. The addition of $H_2O_2$ as an oxidant was a positive effect for the removal rate of humic acid and heavy metals especially in the concentration of 50 mg/L $H_2O_2$.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.509-520
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• 2013

In this study, heavy metals are removed by soil washing from soils contaminated with Cu, Zn, and Pb, whose maximum concentrations are up to 3350, 1220, and 2240 mg/kg, respectively. Through various soil washing experiments, the optimum conditions, including type and concentration of washing reagent, washing time, mixing ratio of soil and washing reagent, and stirring speed, are derived for effective removal of the heavy metals. It is found that the most effective washing reagent and its concentration are hydrochloric acid and 50 mM, respectively. The most suitable washing time is 30 minutes and the optimal mixing ratio of soil and washing reagent is 1:30 (g/mL). The removal efficiency, on the other hand, is not affected by stirring speed. The removal efficiencies of the heavy metals decrease when washing reagent is reused. Furthermore, the heavy metals are readsorbed onto soil in case of consecutive reuse of washing reagent.