• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1239-1244
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• 2010

중금속 및 유류 오염토양 정화를 위해 효율적인 토양세척법과 공정 선정을 목적으로 최적의 오염정화 설계인자를 제시하기 위한 실험적 연구를 수행하였다. 실험분석 항목은 구리, 납, 아연을 포함하는 중금속항목과 총석유계탄화수소(TPH)인 유류항목에 대해 흡광광도법(absorptiometric analysis), 기체 크로마토그래피(gas chromatography)법을 이용하여 단계별로 분석하였다. 실험방법은 최적 세척용매 결정시험, 최적 세척시간 도출시험, 최적 진탕비(S/W ratio) 결정시험 등을 통해 얻어진 결과를 토대로 계면활성제 첨가량별 중금속 용출영향 분석시험 순으로 실시하였다. 실험결과 세척용매인 염산 0.1mole, 체류시간 1시간, 진탕비 1:3 조건에서 오염물질의 저감효과가 우수하게 나타났으며, 이들 조건을 적용하였을 때 1%의 계면활성제를 세척용매에 첨가하였을 경우 추가적인 오염물질의 농도 저감효과가 있는 것으로 분석되었다.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.75-84
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• 2005

The aim of this study is to evaluate the leaching characteristics of lead, copper, cadmium, and mercury from steel making slag by seawater. To demonstrate the leaching characteristics of heavy metals from steel making slag by seawater, it was carried to various leaching tests such as regular leaching tests, liquid/sold(LS) leaching test and pH static test. From the leachability of $Pb^{+2},\;Cu^{+2},\;and\;Cd^{+2}$ from steel making slag in pH static test, it is distinguished between distilled water and seawater. With distilled water, it is very low between pH 7-8 and pH 11-12. On the other hands, with the seawater, its leaching is higher than that of distilled water. In particular, concentration of $Hg^{+2}$ leached from slag by seawater is lower than that of distilled water. Meanwhile, we found that the heavy metals from steel making slag would be dissolved and precipitated using geochemcial equilibrium program such as visual minteq. Lead and copper leached from steel making slag with seawater were dissolved nearly in the range of pH 11-12, but in the range of pH 7-10 those were precipitated about 90%. And cadmium leached from steel making slag with seawater were dissolved completely. On pH static test with distilled water, lead leached from steel making slag seemed to be similar to pH static test with seawater. However, copper and cadmium leached from steel making slag were dissolved. In general, the species of lead leached from steel making slag were formed mainly of $PbCl^+,\;PbSO_4$, the species of copper were formed mainly of $CuSO_4,\;CuCO_3$, the species of cadmium were formed mainly of $CdCl^+,\;CdSO_4$ due to being sorbed with the anions($Cl^-,\;CO_3^{-2},\;SO_4^{-2}$) of the seawater. Both pH static test with seawater and distilled water, it is not in the case of the mercury. Most of mercury leached from steel making slag was precipitated(SI=0). Because the decreasing of $Hg^{+2}$ concentrations depends ferociously on the variation of chloride($Cl^-$) existed in the seawater. $Hg^{+2}$ leached from steel making slag could be sorbed strongly with chloride($Cl^-$) compared of carbonate($CO_3^{-2}$) and sulfate($SO_4^{-2}$) in the seawater. On the basis of that result, we found that the species of mercury was formed of calomel($Hg_2Cl_2$) as one of finite solid. Due to forming a calomel($Hg_2Cl_2$) in the seawater, the stability of mercury species by steel making slag should be higher than those of lead, copper, and cadmium species. Regarding the results stated above, we postulated that the steel making slag could be recycled to sea aggregates due to being distinguishing leachability of heavy metals($Pb^{+2},\;Cu^{+2},\;Cd^{+2},\;and\;Hg^{+2}$) between leaching tests by distilled water and seawater.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.347-353
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• 2002

Dominant rock types of stones used presently for cooking utensils in Korea are pyroxenite, breccia and biotite diorite. Pyroxenite and biotite diorite relatively abundant in mafic minerals have higher specific gravities of 3.0 than breccia of 2.5. Breccia shows the highest absorption (2.9%) among three stones used as cooking utensils and pH value of three stone types shows the alkaline range of 9.7 to 9.9. Among the studied stones used for cooking utensils, biotite diorite is the most durable against abrasion and has the highest strength and therefore, it is expected to be used effectively for the longest time except for other specific causes. Heavy metals such as Cu, Pb, Co, Cr and Ni were leached lower than their detection limit (0.1 ppm) regardless of reaction time and initial pH value of solution. But the leached contents of Fe are various with rock types and leaching conditions and those by acidic solution are generally 1.8 to 31 times higher than those by neutral solution. Breccia and biotite diorite show the highest leached content of Fe in cases of neutral and acidic solutions, respectively. Standard criteria of leached heavy metals and macrominerals should be studied thoroughly to utilize stones for cooking utensils of high quality which are harmless to the human body. Also it is required to examine mon detailed abiochemical properties of various stone types used for cooking utensils.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.1
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• pp.88-95
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• 2009

This study is for understanding the domestic possibilities of the high temperature incineration of waste containing Polychlorinated Biphenyls (PCBs) with the analysis of normal operation case and waste gas, fly ash, dioxin about bottom ash, Total-PCBs, Co-PCBs, and the for analysis the heavy metal leaching feature included by bottom ash and fly ash, heavy metal leaching experiment was implemented. The result shows the dioxin density of the waste gas from waste containing PCBs was $0.00699{\sim}0.00763ng-TEQ/Nm^3$, which is lower than $0.0192ng-TEQ/Nm^3$ from the normal operation case. And each Co-PCBs and total PCBs shows $0.00043{\sim}0.00112ng-TEQ/Nm^3$ and $3.06{\sim}3.87ng/m^3$ respectively. The bottom ash test result shows Dioxin 0.00225~0.00630ng-TEQ/g, Co-PCBs 0.00027~0.00082ng-TEQ/g, Total PCBs 0.9~2.6ng/g, and the fly ash shows Dioxin 0.00164~0.00344ng-TEQ/g, Co-PCBs 0.00053~0.00054ng-EQ/g, Total PCBs 0.64~0.84ng/g. The bottom ash and fly ash experiments for heavy metal leaching did not show any leaching but when it comes to the ingredients of the fly ash, Pb elements shows 31.01~237.7ppm, higher than leaching criterion. The analysis of the density of all air pollution material from the waste gas shows the lower value than permissible criterion.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.47-53
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• 1996

This study was carried out to estimate the amount and the characteristics of sewage sludge disposed of in the Nanjido sludge landfill site. Boring test was conducted to estimated the landfill volume and to get sludge samples to be analyzed. Total analysis and leaching test were performed to find the characteristics of sewage sludge. The Nanjido sludge landfill site had the surface area of $50,000m^2$ and the average depth of 15m. The estimated sludge volume was 600,000ton. Sewage sludge in Nanjido sludge landfill site was very stable. Results of total analysis of heavy metals indicated that the sludge could be classified as a non-hazardous waste according to the California state regulation. The sludge also could be used as compost based on compost quality criteria of foreign countries. Results of Korea Extraction Procedure showed that sewage sludge in Nanjido sludge landfill site was not a hazardous waste.

• Journal of the Korean Ceramic Society
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• v.41 no.11
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• pp.851-857
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• 2004

The stabilizing characteristics of heavy metals in the silicate glass (SD), borosilicate glass (BD), and leadsilicate glass (PD) containing Electric Arc furnace (EAF) dust were studied by the Toxic Characterization Leaching Procedure (TCLP) test. Also, the dependence of the amount of EAF dust upon structural changes of SD, BD, and PD glasses and the TCLP results were investigated by the XRD and FT-IR spectroscopy. In the XRD results, all of SD, BD, and PD specimens containing dust up to 30 wt% were amorphous without crystallizing. In the TCLP test, the concentration of heavy metals leached from the glasses increased with the amount of EAF dust added. The SD specimen series showed the lowest heavy metal leaching and the heavy metal leachate of the PD specimens were lower than those of the BD specimens. But, the Pb leaching from the PD specimens was the highest in the PD glass composition due to the high Pb content. The value of oxygen/network former ratio could be used to compare the chemical durability within the same glass series, but not proper to do between the different glass series. Adding the EAF dust to the SD mother glass, decreased the Si-O-Si symmetry and increased the non-bridging oxygen, which weakened the structure and decreased the chemical durability of glasses. In the BD series glasses, the addition of EAF dust caused the structural changes from tetra-borate group to di-borate group and the formation of the 2-dimensional layer structure of pyre- and ortho- borate, which decreased the chemical durability of glasses. It is concluded that SD series glass among the 3 kinds of glasses is the most effective to stabilize the heavy metals of EAF dust.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.73-82
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• 2017

In Korea, previous certification of water supply infrastructure was mainly focused on economical and physical aspects. Recently, hygienic safety of water supply service has become a sensitive and important issue to our people for evaluating the water quality with growth of economy and education system. According on water quality in 497 Korean water supply facilities, pH values in the supplied water have ranged between 5.8-8.5. However, little is known about metal leachability at the pH conditions observed in the real water supply systems because a fixed pH condition (pH 7.0) has been used in the current standard method, 'Hygienic Safety Testing Method', in water supply. In this work, we examined the effects on heavy metal leachability with pH differences in the water supply pipes which are typically used in Korea. As a result, the amounts of metal leachability were tended to increase when pH levels were decreased. Especially at pH 5.8, Cu leachability from Cu pipes was found to exceed the public health standard level even after applying a normalization factor (NF) given by the current Korea standard method. The Cr and Cu leached from stainless steel pipes, Cd, Pb, Cu, and Zn from Cu-based pipe fittings, and Zn from Zn-based pipe fittings were exceeded the Korean hygienic safety standards while, after applying the NF, concentrations of the leached metals were satisfied with the current Korean standard. The findings from this work provide implications on the needs of reforming the current hygienic safety standard methodology.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.355-359
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• 2005

본 연구에서는 OPC 및 hauyne 클링커의 비산재에 대한 고화특성을 검토하였다. 비산재에 대해 OPC 및 OPC에 hauyne 클링커를 20%까지 대체하였을 때의 압축강도, 길이변화율, 중금속 용출량 등을 조사하였다. 결과로서, hauyne 클링커의 첨가량에 따라 고화체의 압축 강도가 증가하였다. hauyne 클링커의 첨가량은 10%내외가 적합하였으며, 그 이상에서는 길이변화율이 증가하며 팽창하였다. 고화체의 중금속 용출시험결과 모든 배합조건에서 환경기준치이하의 값을 나타내었다.

• Analytical Science and Technology
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• v.12 no.1
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• pp.53-60
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• 1999

Dissolution properties for the 6 inorganic pollutants (As, Cd, Cu, Pb, Zn, Cr) in soils have been studied. These 6 inorganic pollutants were spiked to 3 kinds of fresh soils which were sand, clay, and loam. The dissolution properties of the prepared samples were investigated under the various extracting conditions such as extracting time, acid concentration, particle size, etc. in order to obtain basic information about the process of extraction test and improvement of related analytical methods. As the results, dissolution properties were affected mainly by acid concentration in extracting procedure and mineral composition of soils. On the other hand, extracting time, sort of acids and particle size of soils had a little influence on the dissolution properties. Cd revealed very high dissolving efficiency and As was very low in whole extracting test.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.21-33
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• 2021

The purpose of this study is to determine the order of priority for the use of amendments, matching the optimal amendment to the specific site in Korea. This decision-making process must prioritize the stabilization and economic efficiency of amendment for heavy metals and metalloid based on domestic site contamination scenarios. For this study, total 5 domestic heavy metal contaminated sites were selected based on different pollution scenarios and 13 amendments, which were previously studied as the soil stabilizer. Batch extraction experiments were performed to quantify the stabilization efficiency for 8 heavy metals (including As and Hg) for 5 soil samples, representing 5 different pollution scenarios. For each amendment, the analyses using XRD and XRF to identify their properties, the toxicity characteristics leaching procedure (TCLP) test, and the synthetic precipitation leaching procedure (SPLP) test were also conducted to evaluate the leaching safety in applied site. From results of batch experiments, the amendments showing > 20% extraction lowering efficiency for each heavy metal (metalloid) was selected and the top 5 ranked amendments were determined at different amount of amendment and on different extraction time conditions. For each amendment, the total number of times ranked in the top 5 was counted, prioritizing the feasible amendment for specific domestic contaminated sites in Korea. Mine drainage treatment sludge, iron oxide, calcium oxide, calcium hydroxide, calcite, iron sulfide, biochar showed high extraction decreasing efficiency for heavy metals in descending order. When the economic efficiency for these amendments was analyzed, mine drainage treatment sludge, limestone, steel making slag, calcium oxide, calcium hydroxide were determined as the priority amendment for the Korean field application in descending order.