• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.472-475
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• 2008

중금속으로 오염된 토양을 안정화하고자 석탄 광산 배수 처리 시 발생되는 슬러지를 이용하여 중금속 용출 실험을 실시하였다. 용출 실험을 위하여 슬러지를 무게비율로 0%, 1%, 3%를 완전혼합하고, 3%슬러지를 오염토양과 층을 이루어 용출 실험을 실시하였다. 유입 pH를 5.5-6.2와 3-4로 조절하여 용출실험을 실시한 결과 Cu, Zn, Pb, Cr의 용출 농토는 3% M<3% S<1% M<0% 순으로 나타났다. 오염토양 무게 비율로 3% 슬러지를 완전혼합 시 중금속 용출 실험 결과 20년 기준 안정성을 확보할 수 있었다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.141-144
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• 2003

청양 및 서보광산에서 채취한 광미 및 오염된 토양에 대한 산성비를 고려한 용출실험 결과, 아연, 카드뮴 및 망간 pH 6.2-5.8, 철 pH 5.2-3.2, 코발트 pH 4.4-3.2, 구리 pH 3.2-3.0, 납과비소 pH3.0-3.5의 용출조건에서 최초로 각 원소의 용출이 발생하였다. 반응용액의 최종 pH5.0-1.5사이에서 용출되는 중금속은 이온교환형태 및 탄산염광물형태와 수반된 것이 용해된 것이다. 반응용액의 최종 pH1.5이하에서 용출되는 중금속은 철과 밀접하게 수반된 것으로 해석되었다. 청양광산과 서보광산의 광미가 pH2.0이하로 유지되는 경우가 발생한다면, 청양광산은 비소(최대 6,006$\mu\textrm{g}$/g), 아연(최대 2,503$\mu\textrm{g}$/g) 및 납(최대 29,638$\mu\textrm{g}$/g), 서보광산은 납(최대 2,258$\mu\textrm{g}$/g)과 111소(최대 874$\mu\textrm{g}$/g)의 오염확산이 크게 우려되며, 이 결과는 광미에 대한 환경복원이 필요한 것을 지시한다. 서보광산의 오염된 토양은 pH3.0까지의 산성비와 반응하는 경우에는 중금속의 오염확산이 거의 우려되지 않으며, pH3.0이하의 강산 용액과 반응한다면 아연의 오염확산이 우려된다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.247-248
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• 2005

중금속의 용해도에 미치는 지배요인 중에서 금속의 지화학적 phases, 용액의 pH 및 반응 시간 등이 중금속 원소의 용해에 미치는 영향을 규명하고자 하였다. 실험결과, 청양광산의 과거 광산사무실에 있었던 장소의 광미들은 탄산염광물을 함유하는 것으로 보이고 하천 둑에 땋여있는 광미들보다 산화작용이 더 많이 진행되어 있는 것으로 판단된다.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.45-55
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• 2003

This study investigates the fractional composition and the leaching characteristics of heavy metals in polluted soils due to mining activities. The fractionated composition of heavy metals is classified into five fractions; adsorbed, carbonate, reducible, organic and residual fraction. The status of humic substances in mine wastes of most sites are polyhumic except tailing from Sangdong mine. According to the sequential extraction procedures (SEPs), leaching probabilities of Cd in coal wastes and tailing are relatively low due to high percentage of residual fraction. 46.4% of Ni in tailings from Sangdong mine is probably leached under oxidized environment, and 39.4% of Cu in these tailings is readily extracted under strongly oxidized environment by organic fraction. According to leaching condition of pH 3.0 and pH 5.6, the amount of heavy metals leached out of coal wastes and tailing increases to 1/2 hours. At pH 3.0 and pH 5.6, concentration of Ni in tailing increases up three times of the initial value. Heavy metals released from coal wastes and tailing were not influenced significantly by leaching time.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.81-90
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• 2009

About 35 domestic incinerators are being operated currently. There is waste management policy to reuse waste efficiently and reduce waste through incineration which include reuse, recycling and energy recovery. However, there is a critical social issue that some heavy metals(Cu, Pb) were found in bottom ash from incineration of waste. After incineration, bottom ash is treated with chemicals to prevent second pollution of heavy metals from bottom ash and increase efficiency of heavy metal stabilization.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.469-475
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• 2014

The study investigated the physicochemical characteristics and the ecological risk of the Northport sediment in B city and the releasing properties of heavy metals into seawater during the resuspension also studied. The major components of the sediment are fine silt and clay which contains high organic matter and AVS (Acid volatile sulfide) and the ecological risk of the heavy metals in sediment also very high. The release rate of heavy metals into seawater was in order of Pb>>Cu>Cr>>Zn>Cd during the resuspension in a batch experiment, and the heavy metal release mainly attributed to the oxidation of metal sulfides. Heavy metals which came from easily oxidisable metal sulfides rapidly contaminated seawater within about 1.0 h of the sediment resuspension. The sulfide oxidation during the resuspension increased the residual fraction of heavy metals in the sediment, decreased the organic bound fraction, and changed the other fractions of heavy metals in the sediment. The release of heavy metals from the sediment during resuspension was affected by the resuspension time, the oxidation rate of metal sulfides and resuspended concentration of the sediment particle.

• KSBB Journal
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• v.16 no.4
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• pp.389-397
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• 2001

The effect of sludge digestion on the leaching efficiency of heavy metals from sludge by bioleaching with Thiobacillus thiooxidans MET was investigated. The used sludges were a non- and anaerobically digested. The leaching efficiency of heavy metals was strongly dependent on the pH of the sludge solution rather than the sludge condition and stolid concentration. The lower the pH the more heavy metal was leached from 3.0 of pH. The sequent orders of leaching heavy metals were Zn, Cu, and Cr. Although the buffering capacity of non-digested sludge was similar to anaerobically digested sludge, the pH decrease rate of the anaerobically digested sludge solution was faster than that of the non-digested sludge solution due to the higher sulfur oxidation rate of T. thiooxidans MET in the anaerobically digested sludge. The amount of leached heavy metals from the anaerobically digested sludge showed higher than that of non-digested sludge at the same pH value. This result might be caused by the difference of the insoluble metal types, which were contained in the sludge. An increase in sludge solids concentration decreased the leaching efficiency of heavy metals in the range of solids concentration 10 g/L to 70 g/L. The optimum ratio of S° to sludge stolid was 0.1 in both the sludge. The bioleaching process of heavy metals with T. thiooxidans MET showed the disinfecting effect over 90% as well as the reduction effect in sludge weight of 20%.

• Journal of Soil and Groundwater Environment
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• v.10 no.3
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• pp.1-8
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• 2005

Fractional compositions and leaching potentials of Cd, Cu and Zn were investigated in the soils which had been disposed with the metal processing wastes, tungsten mine tailings and low quality coal mine area. Total concentrations of metals in these soils were higher than in non-polluted paddy and upland soils. Fractions of Cd, Cu and Zn were mostly reducible, organic and residual forms, but varied with origins of wastes. Residual fraction was a predominant form in the nonpolluted soils. Leaching potentials of metals were higher in polluted soils than in non-polluted soils. Metals leached were higher at pH 4.0 than 7.0 and increased with the duration time. After 25 to 35 hrs, metals released from soils reached a pseudoequilibrium. Leaching potential of metals in non-polluted soils was low due to high percentage of residual fractions.

• Resources Recycling
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• v.19 no.2
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• pp.54-62
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• 2010

In order to obtain the basic data for recycling of coal mine tailings, the characteristics of coal mine tailings, the formation of AMD from the tailings and the leaching of heavy metal from the tailings were studied. The samples were characterized in terms of chemical composition, mineral composition and content of heavy metal of the tailings were investigated. The effects of time, temperature, content of pyrite, sulfide minerals on the formation of AMD were also investigated. For the leaching tests, the KS method, TCLP method and column test were used. From the investigated data, we can see that the coal mine tailings can be used as aggregate for filling used gallery. We can also see that the formation of AMD from coal mine tailings can be prevented by mixing 4% or more limestone with it.

• Journal of the Korean GEO-environmental Society
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• v.25 no.5
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• pp.39-47
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• 2024

In this study, the environmental implications of electric arc furnace steel slag, commonly used in road construction and soil reinforcement, were examined. Experiments were conducted to assess the leaching of heavy metals based on particle size and to investigate ion leaching from specimens with varying mixtures of steel slag and clay. The official waste test revealed no detectable heavy metals in the sample items. However, when subjected to leaching experiments and analyzed using ICP-OES, certain heavy metals were found. The reaction of steel slag with water, facilitated by free CaO within the slag, was identified as the cause of leaching. Results showed that aluminum, exhibiting the highest leaching rate, displayed an inverse relationship with particle size. In mixed soil containing steel slag and clay, higher steel slag content resulted in increased aluminum leaching. Nonetheless, the quantity of leached aluminum was notably lower in mixed soil compared to pure steel slag. Furthermore, leaching of other heavy metals remained within acceptable limits. These findings suggest that recycling mixed soil of steel slag and clay for road construction or soil stabilization presents reduced environmental risks compared to using steel slag alone. Utilizing such mixtures could offer an environmentally sustainable and safe alternative.