• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.234-239
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• 2015

Various leaching tests were applied to the soil affected by accidental leakage of HF in an industrial area in Korea. Three different leaching methods including pH-stat, continuous batch leaching, and column tests were adopted to assess leaching characteristics and mobility of fluorine(F) in soil and the potential risks to ecosystem. Both natural and spiked samples were used for the leaching tests. F concentrations in the batch tests increased by leaching rapidly in the early stage of leaching and then maintained rather constant levels. Column leaching test also show similar result to that of the batch test. pH also controlled the leaching behavior of the soil. With increasing pH, more F was released in the pH-stat test. This is mainly due to the competition and exchange with hydroxyl ions, as pH increase to the alkaline range. Most of the F released by the accident seem to have removed in the very early stage of leaching, whereas some natural proportion from soil minerals are thought to have been released very slowly. Therefore, little F released during the accident remained, based on the results of this study on the samples after two years of the accident. We could conclude that soil contaminated by external effects such as chemical accidents should be managed immediately, especially with F.

• Journal of Soil and Groundwater Environment
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• v.6 no.1
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• pp.23-31
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• 2001

Melting is one of the most effective treatments for stabilizing heavy metals and also creates high value by-products. In this study, authors evaluated the leaching characteristics of heavy metals in melting slag obtained by incinerator ashes. In order to evaluate the environmental compatibility of the recycled melting slag, the samples were analysed various leaching tests of heavy metals with raw incinerator ashes, melting slag and the construction materials recycled from melting slag. As the results : (1) The leaching concentrations of the melting slag were lower than those of the raw incinerator ashes in the experiment performed in accordance with Korea Standard Leaching Test (KSLT). (2) The heavy metal concentration of long term leaching test, which was conducted in various pH conditions, were under the standard level of regulation in KSLT. (3) The leaching concentration of mortar samples used for evaluating the feasibility of recycling the melting slag as construction materials also shows the suitable range for recycling. (4) The result of leaching test with the method of RG Min-StB 93, FGSV (Forschungsgesellschaft fur Stra$\beta$en- und Verkehrswesen) met the requirements in German.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.293-301
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• 2005

We conducted several different leaching experiments for assessing the potential environmental risk when utilizing recycled concrete for stabilizing bridge pier. The methods include continuous batch leaching test (DIN 38414-S4), availability test (NEN 7341), pH-stat test (CEN/TC 292/WG6) and tank diffusion test (NEN 7345). The concentration ranges vary depending on the testing method. Nearly all the trace elements were low, some elements recording under detection limit. The maximum concentrations for trace elements leached throughout the whole tests are (as mg/L); Cd (0.029), Cu (0.437), Pb (0.14), Ni, Zn (0.95), Hg (0.005). Although the testing methods we used in this study are much more rigorous than other commonly adapted method including TCLP and domestic testing method for solid waste, the trace elemental concentrations are under the criteria for hazardous material set by the TCLP and domestic method. The result seems to suggest that applying the recycled concrete on stream water will be accepatable practice as for as trace elements are concerned. However, the influence of inorganics such as Ca, Mg, Ni and $SO_4^{2-}$ on aquatic ecology should be further examined.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.76-79
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• 2003

국내의 토양오염 공정시험방법에서는 Zn, Ni 추출시 산분해법에 가까운 방법을 사용하는 반면, Cd, Cu, Pb, $Cr^{6+}$ 추출시 0.1N HCl용액으로 산처리하여 1시간을 진탕한 후 이를 필터로 여과하여 분석용액을 추출하는 용출법을 사용하고 있다(환경부, 2001). 시료내에는 완충 물질이 존재하기 때문에 용출법 사용시 초기 pH 인 1(0.1N HCl)이 유지되지 않아 완충능력이 높은 토양의 경우 현재 국내 공정법상의 용출법이 중금속 오염정도를 추정하는데 적절치 않을 수 있다. (중략)

• Analytical Science and Technology
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• v.11 no.5
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• pp.394-399
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• 1998

This study was carried out to characterize the chemical composition and leaching properties of heavy metals in coal fly ash, which was generated from Korean electrical power utilities in several million tons per year. Comparion with respect to the leachability of heavy metals between the Korea standard leaching test (KSLT) and the American Environment Protection Agency (EPA) method 1311 (TCLP: Toxicity Chracteristic Leaching Procedure) was performed. The concentration of Ag, As, Ba, Cd, Cr, Cu, Pb, Se, Hg in the leacheate was determined by ICP-MS. The analytical result showed a significant difference of the leachability according to the characteristics of the leaching solution except Se, suggesting the necessity of improvement in the leaching test method that is currently implemented in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.62-65
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• 2001

담수와 해수가 혼합되는 환경에서 퇴적 저니로부터의 오염 물질 용출률을 조사하였다. 축산폐수와 산업폐수의 영향을 받은 두 지점의 퇴적저니 시료에 대해 해수와 담수로 장기(약4주) 용출 시험을 행한 결과, 해수보다는 담수에서의 오염물질(영양염류 및 중금속) 용출률이 높은 것으로 조사되었는데, 이는 담수에서의 이온강도(ionic strength)가 상대적으로 낮아 오염성분의 포화농도가 높기 때문인 것으로 판단된다. 또한, 용존산소의 농도를 달리하여 시험한 결과 무산소 상태에서의 용출률이 호기성 상태에서 보다 높은 것으로 나타났으며, 그 원인이 생물학적인 것인지 화학적인 것인지는 밝혀지지 않았다. 시험결과를 종합해 볼 때 무산소 상태의 담수에서 오염물질의 용출이 극대화되며, 따라서 강어귀 등과 같이 유속이 작아져 오염물질의 침강은 잘되는 반면 오염물질의 해수에 의한 희석 효과는 적은 경우가 저니로 인한 수질 환경영향이 가장 클 것으로 예측된다.

• Journal of the Korean GEO-environmental Society
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• v.4 no.4
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• pp.5-16
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• 2003

The aggregate out of waste polyethylene was made in order to recycle waste polyethylene wasted in the country side. Many physical and mechanical experiments which include leaching test, specific gravity test, compaction test, LA abrasion test, large-scaled shear test, and permeability test were performed for the waste polyethylene aggregate. The thermal conductivity test, unfrozen water content test and frost heave test were also performed. The temperature distribution for both gravels and waste polyethylene aggregate, which were constructed in the frost heave layer in the field, was measured in winter season of continuous 2 years and compared.

• Journal of the Korean Geotechnical Society
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• v.17 no.2
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• pp.143-150
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• 2001

최근 국내에서는 건설재료의 부족으로 건설부산물인 폐콘크리트를 새로운 토목재료로써 재활용 또는 자원화에 노력하고 있다. 이러한 차원에서 폐콘크리트의 재활용 및 자원화는 사용용도에 적합한 공학적 특성뿐만 아니라 환경적 특성을 분석하여 대상재료의 환경 안정성을 파악해야 한다. 따라서, 본 논문은 폐콘크리트에 대하여 pH시험, 용출시험, 중금속 흡착특성 등 일련의 환경특성 실험을 실시하여 폐콘크리트 사용에 따른 주변 환경에 미치는 영향을 분석하였다. 실험결과, 폐콘크리트의 pH는 11~12정도이고, 폐기물공정시험법과 TCLP법에 의한 용출시험은 법적기준에 모두 만족하는 것으로 나타났다. 또한 중금속 흡착시험은 폐콘크리트나 구리, 납, 카드늄의 제거능이 큰 것으로 나타났으나 반면, 크롬에 대해서는 제거율이 50%정도로 나타났다.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1253-1257
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• 2010

그라우팅은 건설공사에서 지반의 갈라진 틈이나 공동, 공극 등에 적절한 충전재를 압력을 이용하여 주입하는 것으로, 굴착공사 시 누수방지와 불안정한 지반의 보강을 위하여 광범위하게 사용되고 있다. 가장 많이 사용되고 있는 그라우팅 주입재의 재료로는 물유리계를 주재료로 사용하는 약액주입공법이 많이 사용되어지고 있다. 기존의 물유리계 재료를 사용할 경우 발생하는 용출현상 및 강도저하를 보완하기 위하여 가소성을 부과한 무기질계 재료ECG(Eco Clean Grouting)를 사용하여, 강도 및 내구성이 우수하고 주입재의 용출 현상이 발생하지 않아 환경오염 문제가 거의 없는 영구적인 차수 및 보강에 적합한지와 친환경적 특성을 확인한다. 본 연구는 가소성 무기질계 재료인 ECG(Eco Clean Grouting)재료를 사용하여 현재 많이 사용되는 재료인 물유리계 재료로 일축압축강도, 체적변화, 내구성 평가, 투수시험, 어독성 시험, 용탈시험등을 수행하여 비교 분석 하였다. 일축압축 시험결과 재령 28일 강도는 ECG가 물유리재료에 비해 크게 발현되었고, 내화학성시험 결과 ECG의 길이변화율이 거의 없는 것으로 내화학성에서 강점을 보였다.

• Analytical Science and Technology
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• v.14 no.3
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• pp.253-258
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• 2001

This is a research on hazardous characteristics and potentials of bottom ash from 9 municipal solid waste combustors(200 tons/day) of Korea by the test methods of leaching and content. The leaching method was performed by Waste Test Method of Korea. In case of the content method, mercury was determined by thermal decomposition amalgamation atomic absorption spectrometer, other 9 elemets including Pb, which were pretreated by U.S.EPA SW-846 3050B method, were determined by flame atomic absorption spectrometer(FAAS) or inductively coupled plasma atomic emission spectrometer(ICP-AES). Results of leaching test showed that Pb and Cu was main pollutants. It was interested that the distribution rate of metals' contents of each combustors was similar and the rank of concentration was Fe>Zn>Cu>Mn>Pb>Cr>As>Cd>Hg.