• 제목/요약/키워드: Mixing soils

검색결과 187건 처리시간 0.028초

논 토양에서 석탄회와 석고의 혼합제를 활용한 인산유출 저감 (Effects of Fly Ash and Gypsum Mixture on Reducing Phosphorus Loss from Paddy Soil)

  • 이용복;이슬비;오주환;이창훈;홍창오;김필주
    • 한국환경농학회지
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    • 제27권1호
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    • pp.66-71
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    • 2008
  • 농경지 인산유출 저감을 위한 석탄회-석고의 적정혼합비를 실내시험을 통해서 선발하고 이를 논토양에서 적용 가능성을 평가하였다. 석탄회-석고 혼합제 시용은 두 토양(LS, SiL)에서 토양 중 dissolved reactive P(DRP) 함량을 현저히 감소 시켰다. 그러나 석탄회-석고 혼합비 75:25, 50:50 및 25:75 처리간에 토양 중 DRP 감소 효과는 큰 차이가 없었다. 따라서 석탄회-석고 75:25 혼합제 0, 20, 40, 60 Mg $ha^{-1}$를 논 토양에 시용하여 벼 재배 기간동안 DRP 함량과 수확 후 형태별 인산 함량변화를 조사하였다. 혼합제 시용량 증가에 따라서 토양 중 DRP 함량은 감소하였으나, 수확 후 토양 중 Ca-P 함량은 혼합제 시용량 증가에 따라서 증가되었다. 그리고 혼합제 시용량 증가에 따라서 토양 중 유효인산, 유효규산 및 치환성 칼슘 함량이 현저히 증가되었다. 따라서 석탄회-석고 혼합제는 토양 중 인산의 용해도를 감소 시켜 농경지로부터 인산유출을 저감시킴과 동시에 토양 비옥도 증진에 우수한 제재로 평가되었다.

바이오매스 회분 혼합에 따른 토양 내 중금속 (Ni, Cr) 안정화 (Stabilization of Heavy Metal (Ni, Cr) in Soil Amended with Biomass Ash)

  • 강구;박성직;홍성구
    • 한국농공학회논문집
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    • 제58권3호
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    • pp.39-46
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    • 2016
  • This study investigated the potential use and the effectiveness of biomass ashes for the stabilization of heavy metals in soil through a series of experiments. The ashes used for the experiments were obtained from the gasification of biomass including miscanthus and woodchips. The amounts of nickel and chromium released from the soil and ash mixture were analyzed. Chemical analysis showed that the ash contained unburned carbon as well as silica and alkali metals. Miscanthus ashes have C (83.400 %) > Si (9.040 %) > K (3.180 %) > Ca (1.800 %), and woodchip ashes have C (93.800 %) > Ca (2.220 %) > Fe (1.370 %) > K (1.200 %). KSLT and TCLP test results implied that the heavy metal concentrations were below the environmental standards and would not impose the risks. The results also showed that Ni releases were more limited as more ashes were mixed with the soil due to the increases in exchangeable, carbonate, and oxide nikels. Both miscanthus and woodchip ahses were effective in stabilizing nickel and chromium through mixing with the soil. It could be seen that ashes produced from biomass gasification can be used to stabilize the heavy metals in soils.

폐스티로폴 입자와 현장 발생토를 활용한 경량혼합토의 공학적 특성 (Engineering Characteristics of the Light Weight Soil Used Recycled Stylofoam Beads and Disposal Soils)

  • 신방웅;이종규
    • 한국지반환경공학회 논문집
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    • 제1권1호
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    • pp.43-50
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    • 2000
  • 본 논문은 폐스티로폴과 현장발생토를 활용하여 경량성토재로서의 특성을 파악하고자 하는데 목적이 있다. 폐스티로폴 입자는 가볍고 단열성이 좋으며 진동차단효과도 우수하기 때문에 경량성토재로서의 활용이 가능하다. 특히 스티로폴은 1996년 재활용품목으로 선정되어 토공재료로서의 적합성만 확인된다면 체계적인 공급이 가능하다. 따라서 본 논문에서는 폐스티로폴 입자와 현장발생토를 혼합한 후 혼합비와 고화재의 투입량을 변화시켜가며 다짐시험, 일축압축시험, 정수위 투수시험, CBR 시험, 실체현미경분석을 실시하였으며, 그 결과 폐스티로폴을 활용한 혼합토가 강도, 투수, 지지력 특성이 우수한 것으로 나타나 토공재료고서 사용가능한 것으로 나타났다.

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화강풍화토를 이용한 CLSM의 공학적 특성평가 (Evaluation of Engineering Properties of CLSM using Weathered Granite Soils)

  • 임유진;서창범
    • 한국방재학회 논문집
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    • 제9권3호
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    • pp.19-26
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    • 2009
  • 본 연구는 뒷채움재로 사용하는 입상재료의 다공성으로 인하여 발생하는 강성 부족과 이로 인한 변형발생 등의 문제를 극복하기 위한 방법으로서 국내 지표특성상 가장 풍부한 화강풍화토를 사용한 유동성뒷채움재(CLSM)의 배합특성을 분석하였으며 설계배합비에 따른 강도와 강성 발현 특성을 자유단공진주시험(FF/RC), 공내재하시험(PMT) 및 동적평판재하시험(LDWT) 등으로 분석하여 향후 뒷채움재용 화강풍화토 CLSM의 설계 및 시공에 필요한 기초 데이터를 제시하였다.

Desorption Kinetics and Removal Characteristics of Pb-Contaminated Soil by the Soil Washing Method: Mixing Ratios and Particle Sizes

  • Lee, Yun-Hee;Oa, Seong-Wook
    • Environmental Engineering Research
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    • 제17권3호
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    • pp.145-150
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    • 2012
  • Pb-contaminated soil at a clay shooting range was analyzed by the sequential extraction method to identify metal binding properties in terms of detrital and non-detrital forms of the soil. Most of the metals in the soils existed as non-detrital forms, exchangeable and carbonate-bound forms, which could be easily released from the soil by a washing method. Therefore, the characteristics of Pb desorption for remediation of the Pb-contaminated soil were evaluated using hydrochloric acid (HCl) by a washing method. Batch experiments were performed to identify the factors influencing extraction efficiency. The effects of the solid to liquid (S/L) ratio (1:2, 1:3, and 1:4), soil particle size, and extraction time on the removal capacity of Pb by HCl were evaluated. Soil samples were collected from two different areas: a slope area (SA) and a land area (LA) at the field. As results, the optimal conditions at 2.8 to 0.075 mm of particle size were 1:3 of the S/L ratio and 10 min of extraction time for SA, and 1:4 of the S/L ratio and 5 min of extraction time for LA. The characteristics of Pb desorption were adequately described by two-reaction kinetic models.

카올리나이트의 침식특성 (Erosion Characteristics of Kaolinite)

  • 이주형;곽기석;박재현;정문경
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.533-537
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    • 2004
  • The erodibility of soil is an important factor to scour, especially in fine-grained soils. In this study, the erosion characteristics of kaolinite are quantified through the scour rate tests using the Erosion Function Apparatus called EFA. The basic soil property tests are also performed. The kaolinite samples are prepared by mixing with distilled water and formed to the designed maximum consolidation pressure of 60, 110, 160, 240, 360kPa, respectively. The results of the scour rate tests are presented in a format of a plot showing the relationship between erosion rates and shear stresses. Erosion properties of kaolinite showed a striking contrast according to the maximum consolidation pressure, and a correlation was established between the erosion properties of kaolinite and the soil properties; water content, undrained shear strength, dry density.

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유기산 추출에 의한 철 폐광산 오염토양의 복원 (Ex-situ Remediation of a Contaminated Soil of Fe Abandoned Mine using Organic Acid Extractants)

  • 정의덕;강신원;백우현
    • 한국환경과학회지
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    • 제9권1호
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    • pp.43-47
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    • 2000
  • A study on the remediation of heavily for ion contaminated soils from abandoned iron mine was carried out, using ex-situ extraction process. Also, oxalic acid as a complex agent was evaluated as a function of concentration, reaction time and mixing ratio of washing agent in order to evaluate Fe removability of the soil contaminated from the abandoned iron mine. Oxalic acid showed a better extraction performance than 0.1N-HCl, i.e., the concentrations of Fe ion extracted from the abandoned mine for the former at uncontrolled pH and the latter were 1,750 ppm and 1,079 ppm, respectively. The optimum washing condition of oxalic acid was in the ratio of 1:5 and 1:10 between soil and acid solution during l hr reaction. The total concentrations of Fe ion by oxalic acid and EDTA at three repeated extraction, were 4,554 ppm and 864 ppm, respectively. The recovery of Fe ions from washing solution was achieved, forming hydroxide precipitation and metal sulfide under excess of calcium hydroxide and sodium sulfide. In addition, the amounted of sodium sulfide and calcium hydroxide for the optimal revovery of Fe were 15g/$\ell$ and 5g/$\ell$ from the oxalic acid complexes, respectively.

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단층형 매립지 최종복토시스템의 현장 적용성 평가 (The Evaluation on In-Situ Adaptability of Mono-layer Landfill Final Cover System)

  • 유찬;윤성욱
    • 한국농공학회논문집
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    • 제48권5호
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    • pp.73-80
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    • 2006
  • The mono-layer cover system is composed of soils only as a filling material and various plants are planted on the surface to control the water balance in the cover system. In this paper, the mono-layer cover system was considered as an alternative landfill final cover system and developed a model that could utilize industrial by-product (especially, coal ash & phosphogypsum) as additive filling materials. The mixture of granite soil, coal ash, and phosphogypsum was placed as a cover material in a box constructed with cement. Laboratory tests were carried out to investigate the environmental effect on the utilization of coal ash & phosphogypsum and to determine the mxing ratio of each materials. In the leaching test, all materials showed lower heavy metal concentration than the threshold values of regulation. The optimum mixing ratio of materials which was applied to field model test was determined to soil (4) : coal ash (1) : phosphogypsum (1) on the volume base. Field model tests were continued from February to July, 2004 in the soil box that was constructed with cement block. It was verified that coal ash and phospogypsum mixed with soil was to be safe environmentally and the water balance of mono-layer cover system was reasonable.

옥상녹화공법의 배수층 구조별 식물생육 효과 (Effects of Drainage Types of Soil Media on the Plant Growing in Rooftop Planting)

  • 이은엽;문석기
    • 한국환경복원기술학회지
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    • 제3권4호
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    • pp.11-21
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    • 2000
  • This study was aimed to establish different drainage types of soil media on the plant growing in rooftop. For this study, experiment plots were installed on the roof of Social Science building, Chongju University, from April, 1998 to September, 1999. (1) Sand and sandy loam as base and check soils, (2) vermiculite as a inorganic soil media (3) "humus sawdust" and "burned rice hull" as organic soil media were used by various mixing ratio Zoysia japonica, was selected for the experiment. The results of this study are as follows : L5B3S2 and L5H3S2 of bad drainage character with a plastic drainage plate combination caused good growth effect on Zoysia japonica examined in 3 types of drainage layer with 5 types of soil media. From this result, it could be suggested that combined design of plastic drainage plate with 2 soil types - L5B3S2 and L5H3S2 - be desirable composition for regarding weight load and plant growth.

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재활용재료를 포함한 옥상녹화용 인공토양의 성능평가 - 토양배합비가 자생식물 생육에 미치는 영향을 중심으로 - (A Study on Green Roofing Applied Artificial Soil Containing Recycled Materials - Focused on the Effects on the Growth of Plants by Difference of Soil Mixture Ratio -)

  • 김경훈;고정현;김용
    • 한국환경복원기술학회지
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    • 제16권5호
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    • pp.119-130
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    • 2013
  • The objective of this study was to analyze an availability of green roof soil based on the bottom ash soil and compost using sludge derived from food factory as comparing and analysing the growth of native plants. Analysing the physical properties and chemical resistance of 12 different type mixing soils which is mainly used in green roof, selected 4 types of soil, experiments were conducted to compare plant growth. The growth status of the plant showed the most superior of the soil 13(control), next soil 9(Pearlite : Bottom Ash : Compost = 20 : 60 : 20) and soil 10(Pearlite : Zeolite : Compost = 60 : 20 : 20) This result showed that native plants grow well in the soil based on the bottom ash and compost using sludge derived from food factory, and this soil type is determined that is available the green roof soil.