• Korean Journal of Soil Science and Fertilizer
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• v.36 no.2
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• pp.86-91
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• 2003

Carbon material such as graphite and activated charcoal can promote the growth of some formsog bacteria. We examined whether this bacterial growth promoting effect can have a positive influence on field crops. Refined graphite was mixed into the standard soil used in rice cultivation. Varying soil graphite mixtures of 0.1%, 0.5% and 1% were used to cultivate rice seedling for 3 weeks. After transplanting in the filed, rice plants were cultivated for 4 months. To observe the effect of graphite(carbon material) during the cultivation of rice, we examined various different growth components in this research. During the transplanting stage, growth promoting effect of carbon was observed in the 0.1% carbon added soil. However, there were not much difference between graphite added soil and standard soil in the other stages. Rice yield was highest in the soil with 0.1% graphite.

• Journal of Korean Society of societal Security
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• v.4 no.2
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• pp.49-56
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• 2011

The hydroxide precipitation method is appropriate to distinguish free metal ions with complexed metal ions with amino acids. Optimum pH conditions of hydroxide precipitation were investigated using mixed amino acids which have similar composition ratio with hydrolyzed amino acids. When applied to soil samples immobilities of Hg, Cr, and Cu ion with mixed and hydrolyzed amino acids were reasonable. But those of Cd and Zn were not sufficient.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.11a
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• pp.213-234
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• 2002

우리 나라는 70년대까지 광업은 부흥하였으나, 그 이후 급속히 위축되면서 80년대 이후 거의 대부분 광산들이 폐광 또는 휴광된 실정이다. 그 결과 현재 전국 각지에 다수의 폐갱도가 존재하게 되었으며, 이제는 지반침하 및 각종 침출수의 원인자로 간주될 정도이다. 최근 지자체에서는 이런 폐갱도를 지역 자원으로서 가치를 인정하고 지역 활성화를 위해 재 이용하려는 움직임이 보이고 있는데, 구체적으로는 관광시설, 연구시설, 농업생산시설, 저장시설, 폐기물처리시설 등이다. 일본은 폐광된 금속광산 재활용을 위해 입지여건과 주변지역, 입갱 가능성 등 기초조사를 하였다. 조사결과 폐갱도의 문제점으로 입갱이 가능한 광산이 적다는 점을 들 수 있다. 대부분의 광산은 갱구가 함몰되었거나, 갱내에 지하수가 차 있어 접근이 불가능한 경우가 대부분이다. 비교적 양호한 암반 경우는 서브 레벨 스토핑, 잔주, 주방식 등의 채굴법에 의해 대규모 공동이 잔존하고 있는 경우도 있지만 그리 많지 않았다. 폐광된 광산 재활용 여건은 우리 나라와 일본이 대동소이 경우로 현실적으로 활용이 가능한 폐광은 많지 않으며 활용코자 할 때에는 기존갱도를 활용하면서 암반이 견고한 곳에 새로운 갱도를 설치하여야 한다. 그러나 몇몇 곳에서는 매우 유용하게 잘 활용되고 있는 곳도 있고, 연구 검토하면 충분한 활용성이 있다고 생각되는 곳도 있다. 그러므로 현재의 상황을 보고 판단할 것이 아니라, 활용기술과 접목해서 활용성을 검토함으로써 불용 자산의 유용화 방안이 검토되어야 할 것이다. 현재 가행중인 광산은 입지여건 및 암반이 양호하고, 대형갱도를 굴착하는 석회석광산 등을 선택하여 폐광 후 활용이 가능토록 채광기술 발전시켜 나가야 하며, 인간 중심적인 시설 또는 산물 중심적인 시설로 구분하여 폐광 후 복구비용을 우선 지원하는 방식 등을 통하여 시추, 탐광굴진, 현대화, 수갱굴착, 자금융자 등을 지원하는 우리 공사와 산업자원부가 지자체, 산림청, 건교부, 농림부 등과 연계하여 종합적인 지원육성책을 마련하여야 할 것이다. 결과적으로, 지방자치단체 등에서 관심을 갖고 있는 저장시설, 폐기물처리시설, 관광시설, 농업생산시설, 연구시설 등을 중심으로 ＆apos;광산 채굴적을 미래에 어떻게 활용한 것인가＆apos;를 선진외국 사례를 벤치마킹하고, 연구ㆍ검토하여 친환경적인 광산개발이 되도록 기본적인 방향과 개념을 갖도록 하여 관련 정책을 계획적이고, 체계적으로 수립 일관성 있게 추진해 나가야 할 것이다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.161-166
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• 2021

This study was on leaching test(KSLT) of the aggregate for the products to evaluate the characteristics of contaminants and the possibility of contamination arising from the aggregate. On the basis pH, conductivity, turbidity, TN, TP, COD and heavy metal contents in the aggregate increased as the particle size of the aggregate was smaller. The pH appeared to be 9.9~11.4 which is relatively higher than soil, however, heavy metal has investigated within the 1 region's standard value of soil pollution standards. From the leaching test, there is strong indication that the risk of pollution due to elution of pollutants gets higher with the smaller grain size. Especially conductivity and turbidity are the potential water pollution source and recycled aggregates of 10mm or less could be a potential pollution source since it could elute soluble matters and suspended solid, but there is no proper management standard for them. As a result of evaluating water pollution possibility of the aggregate, the pH displayed in items with a very high possibility of contamination, TN and TP did in item with a low possibility of contamination and on the other hand the heavy metals did in item with a very low possibility of contamination.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.217-223
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• 2010

In general, fiber-reinforced plastics (FRP) wastes are simply buried or burned. Landfill brings about a permanent contamination of soil due to the inability of FRP to decompose and incineration causes an issue of generating toxic gases and dusts. There have been several ways to treat the FRP wastes such as landfill, incineration, chemical recycling, material recycling and the utilization of energy from combustion. Most methods excluding material recycling are known to have critical limitations in economic, technical and environmental manners. However it is known that material recycling is most desirable among the methods handling FRP wastes. In this study, to investigate the purpose of feasibility of material recycling, various bulk molding compound (BMC) specimens were prepared with the various contents of unsaturated polyester resin binder (25, 30, 35 wt%) and the various replacement ratios of FRP wastes powder (0, 25, 50, 75, 100 wt%) substituted for filler. To evaluate the physical properties BMC specimens, various tests such as tensile strength, flexural strength, impact strength, hot water resistance and SEM imaging were conducted. As a results, mechanical strengths decreased with an increase of replacement ratio of FRP waste powder and physical properties of BMC specimens were deteriorated in the hot water resistance. The fluidity of BMC with more than 50 wt% of the replacement ratio of FRP wastes powder decreased remarkably, causing a problem in the BMC composite.

• Journal of the Korean Geosynthetics Society
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• v.11 no.4
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• pp.9-16
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• 2012

Standardized remediation process for the soil contaminated with arsenic is insufficient due to characteristics of its anion-mobility and speciation changed by Eh-pH of soil. One of the well-known efficient remediation processes is the modified soil washing that particle separation process by only water. However, it is required that the treatment plan for the fine soil what was discharged after modified soil washing. Therefore, this research suggests the treatment plan that the recycling method using arsenic immobilization by FeS-$H_2O_2$. The batch experiments results for the arsenic immobilization showed that the water content was at least 50%, the injection of FeS and $H_2O_2$ (assay-35%) were 8% (w/watdrybase) and 0.2 mL/10 g of fine soil respectively. Arsenic concentration with KSLT was decreased about 95.4%. The results indicated that the mixing of FeS-$H_2O_2$ was highly efficient on the immobilization of As-contaminated soil. The mixing ratio as 13% of bentonite with 3% of cement (at based on 100% of immobilized fine soil) was satisfied with standard of liner for landfill construction.

• Proceedings of the Turfgrass Society of Korea Conference
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• 2011.02a
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• pp.25-32
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• 2011

본 연구는 화력발전의 부산물로 발생하는 석탄바닥재가 골프장 사질 토양의 개량재로 사용 적합한지를 평가하기 위해 수행되었으며, 결과를 요약하면 다음과 같다. 1. 석탄바닥재의 화학성을 분석한 결과 총질소 0.34%, 가용성 인산 $52mgL^{-1}$, 치환성 칼륨 $51mgL^{-1}$ 뿐만 아니라 소량의 치환성 칼슘과 마그네슘을 함유하고 있어 식물생육에 이롭고, 유해중금속함량은 Cd, $Cr^{6+}$, Pb, Ni, As는 $1mgL^{-1}$ 이하, Cu 농도는 $1.25mgL^{-1}$ 검출되어 토양환경보전법의 토양오염우려기준 이하이므로 석탄바닥재 재활용으로 인한 토양오염 가능성은 매우 낮은 것으로 판단된다. 2. 모래 토양에 석탄바닥재를 부피비로 0~50% 비율로 혼합한 시료의 투수계수와 유효수분함량을 측정한 결과 석탄바닥재 혼합비율이 증가할수록 투수계수는 유의성 있게 감소하고 유효수분함량은 유의성 있게 증가해 석탄바닥재가 모래 토양의 낮은 수분보유력을 개선하는 효과가 있음을 확인하였다. 3. 모래 토양에 석탄바닥재를 부피비로 0~50% 비율로 혼합한 시료를 잔디식재층으로 조성한 라이시미터에 잔디종자 파종 후 약 4개월 뒤 잔디밀도가 완전히 형성된 후에 시비 후 3일 간격으로 채취한 용탈수를 분석한 결과 1일과 4일 후에 채취한 초기 용탈수에서는 석탄바닥재 혼합비율이 높을수록 $NO_3-N$, $NH_4-N$ 및 K함량이 유의성 있게 감소했으며, 대조구에 비해 석탄바닥재 혼합비율이 높은 처리구일수록 $NO_3-N$, $NH_4-N$ 및 K함량이 용탈수 채취기간 동안 지속적으로 용탈되었다. 이 결과로 석탄바닥재가 모래 토양의 낮은 양분 보유력을 개선하는데 효과적이고 석탄바닥재처리가 대조구에 비해 오랫동안 식물 생육에 필요한 양분을 공급하는 효과가 있음을 확인하였다. 4. 골프장 그린상구조와 동일한 시험포장을 만들고 모래 토양에 석탄바닥재 10%와 20% 그리고 피트, 액시스, 이소라이트를 부피비로 10% 비율로 혼합한 시료를 잔디식재층으로 조성하고 크리핑 벤트그래스(Agrostis paulstris Huds), Penn A-4 $10gm^{-2}$을 파종한 후에 처리구별로 잔디 품질을 평가하기 위해 잔디 밀도, 뿌리길이, 색상 및 시각적 품질을 조사한 결과 석탄바닥재 처리구는 기존에 사용하는 개량제인 피트, 액시스, 이소라이트 처리구와 동등한 잔디생육 촉진 효과가 있는 것으로 조사되었다. 5. 결론적으로 석탄바닥재는 골프장 토양의 물리적 특성과 화학적 특성을 개선하고 잔디생육에 필요한 양분을 공급하는데 효과적인 토양개량재라고 할 수 있다.

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.24-31
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• 2004

A cold mix asphalt (CMA) treatment process was proposed as a tool to recycle soils contaminated with petroleum hydrocarbons. Experimental studies were conducted to characterize performances of the CMA process in treating soils contaminated with diesel or diesel compounds. From the screening experiments, it was found that performances of five types of asphalt emulsions that contained a cationic or an anionic or a nonionic surfactant were not substantially different. In consideration of higher affinity for soils and higher sorption coefficients obtained, an emulsion containing Lauryl Dimethyl Benzyl Ammonium Chloride (LDBAC) was selected as a promising asphalt emulsion for treating diesel-contaminated soils. When the asphalt emulsion LDBAC was applied to treat three compounds that originated from diesel, the removal efficiencies obtained in the order of decreasing efficiencies were as follows: docosane > pentadecane > undecane. Leaching experiments on the specimen formulated by the emulsion LDBAC found that the selected treatment method could treat soils with diesel concentrations as high as 10,000 mg/kg. Leaching of the diesel from the specimen was controlled by diffusion for the first four days and then leaching rate diminished substantially. The latter behavior was characterized as depletion, which represents that the contaminant released amounts to more than $50\%$ of the total amount of the contaminant that can be leached. The amounts of three diesel compounds leached from the specimen in the order of decreasing amount were undecane, pentadecane, and docosane. The curing of the soil contaminated with pentadecane was relatively slow.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1095-1104
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• 2009

The objective of this research was to evaluate the feasibility of using oyster-shell and eggshell wastes for the stabilization of arsenic-contaminated soil. Artificial As(V) contaminated soil was mixed with 0~5% oyster-shell and eggshell wastes and each sample was incubated for 30 days in a controlled environment. The efficiency of each treatment was evaluated using various single extractants (1 N HCl, 0.1 N NaOH and 0.5 N $H_2SO_4$). The concentration of As(V) was reduced by 10% upon a 5% oyster-shell or eggshell waste treatments based on the Korea Standard Test method (1 N HCl extraction). Analogous trends were observed in the 0.1 N NaOH or 0.5 N $H_2SO_4$ extractions. In addition, the oyster-shell and eggshell waste treatments increased the pH of each soil from 6.54 (Control) to 7.62~7.94. The exchangeable Ca in each soil also sharply increased from 6.87 cmol(+)/kg (Control) to 12.77~20.18 cmol(+)/kg. Further research is needed to increase the effectiveness of the oyster-shell and eggshell waste for the stabilization of As(V) in the contaminated soil.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.252-258
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• 2018

A larger energy consumption and concentration of population induced green house gas glowing and heat island effect in the urban space. Roof green system was a effect method to reduce green house gas and heat concentration in the city. Therefore, construction of this system was increasing. Most of lightweight soil used in roof green system was perlite, but this caused dust and skin disease. So it needed to develop another new lightweight soli for roof green system. Meanwhile, a thermoelectric power plant generated bottom ash as a by-product. According to previous research, bottom ash could be used for artificial lightweight soil with 60 wt% of mixing rate. But this study was proceed to develop a artificial lightweight soil using bottom ash with higher mixing rate by 65 wt% and different organic ingredients. First, physical and chemical properties of bottom ash was investigated. Then test according to landscaping design standard was proceeded for various artificial lightweight soil mix types using bottom ash, bark, compost and coco peat. As a result, the artificial lightweight soil with 65% of bottom ash, 30% of bark and 5% of compost was suitable for low and middle range of soil standard.