• Advances in environmental research
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• 제3권4호
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• pp.337-353
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• 2014

The determination of the effectiveness of the immobilization of blasting dust (waste generated in galvanic activities) in cement matrix, as well of mechanical, physical and microstructural properties of concrete paving blocks produced with partial replacement of cement was the objective of this work. The results showed that blasting dust has high percentage of silica in the composition and very fine particle size, characteristics that qualify it for replacement of cement in manufacturing concrete blocks. The replacement of Portland cement by up to 5% residues did not cause a significant loss in compressive strength nor increase in water absorption of the blocks. Chemical tests indicated that there is no problem of leaching or solubilization of contaminants to the environment during the useful life of the concrete blocks, since the solidification/stabilization process led to the immobilization of waste in the cement mass. Therefore, the use of blasting dust in the manufacture of concrete paving blocks is promising, thus being not only an alternative for proper disposal of such waste as well as a possibility of saving raw materials used in the construction industry.

• 대한환경공학회지
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• 제30권10호
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• pp.1034-1038
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• 2008

분해성 고형화/안정화(DS/S, degradative solidification/stabilization)는 전통적인 고형화/안정화(S/S, Solidification/Stabilization)에 경제성과 유기 오염물질의 분해를 추가한 기술이다. 무기 오염물질은 고정되며 유기 오염물질은 DS/S시스템에 의해 분해된다. 본 연구에서는 액상폐기물 내의 클로로포름(CF)과 메틸렌클로라이드(MC) 분해를 위해 cement/slag/Fe(II)시스템을 바인더로 한 DS/S의 효율성을 평가 하였다. 초기 CF의 농도는 0.26 mM, 1.0 mM, 8.4 mM, 25 mM and 42 mM 그리고 Fe(II) 농도는 200 mM로 하였다. 실험결과 다양한 농도의 CF의 분해경향은 유사일차반응으로 표현할 수 있었으며 초기농도 0.26 mM에서 5일 이내에 95%가 분해되었다. MC의 분해를 촉진시키기 위하여 중금속 50 mg/L을 추가하였으나 분해는 거의 이루어지지 않았다. 따라서 MC의 분해를 위해서 추가적인 고찰이 필요하다고 판단되며 다른 반응 경로의 부산물에 대한 추가적인 고찰을 통해 cement/slag/Fe(II)에서 메탄 계열의 염소계유기화합물의 명확한 분해 경로와 메카니즘을 파악할 수 있을 것이다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.116-117
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• 2014

This study is to environmental safety assessment of ground solidification materials using industrial by-products. also, physical and chemical properties were investigated. as a result, compared to conventional cement the survival rates are capable, was judged to be possible utilizing of ECO-friendly ground solidification materials.

• 한국환경보건학회지
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• 제19권2호
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• pp.46-54
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• 1993

This study was carried out on the stabilized/solidified treatment for the reducing leachability of hazardous heavy metals copper, lead, chromium and cadmium in the hazardous sludge which treated to be unleached heavy metals by sodium diethyl dithiocarbamate. Cement matrix was analyzed for the leachability of 24 hrs and dynamic leaching test, structure and the optimum condition for the stabilization and solidification of the hazardous sludge. In 28 days of curing time the unconfined compressive strength was 21.5 kg/cm$^2$ at the ratio of portland cement (0.5)+fly ash (0.25) and 23.5 kg/cmz at the ratio of portland cement (0.5)+fly ash (0.25) + cake (0.25). High concentration of Pb, Cr and Cd in the sea water and Cu in the distilled water were leached at the dynamic leaching test. The concentration of leaching heavy metals for specimens which were tested 24 hrs were found low leachability with decreasing pH of leachant. According to dynamic leaching test, the low level of copper, lead, cadmium and chromium were leached in the cement matrix with sodium diethyl dithiocarbamate. But the effective diffusion coefficient of unleached cement matrix which was treated sodium diethyl dithiocarbamate was decreased above 2 times than that of cement matrix. The relation of leachant renewal period (Y) and cumulative fraction ion leached (X) was the following regression equations. Solidification with unleached agent. Y$_{Cu}$ = 1413752X + 247, Y$_{Pb}$ = 223501IX + 214, Y$_{Cr}$ = 8310601X - 472, Y$_{Cd}$ = 168787X + 1061 The structure of' solidified matrix with X-ray diffraction analysis was composed more Ca(OH)$_2$, Si, Mg(OH)$_2$ and Al in the unleached cement matrix than those in cement matrix.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.388-394
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• 1998

In this study, the influence of soil contaminant on the cement solidification treatment was considered. Unconfined compression strength(UCS) test was carried out for solidificated specimen, Setting time was measured for cement slurry that was mixed with leachate and wastewater. It was appeared that treatment effect were affected by the the kind of soil, organic content, component of pore water and its concentration. And UCS of samples which were cured in the leachate were decrease about l/5. Especially for the marine clay, UCS of samples which were cured in leachate during 180 days were smaller than 90 days cured samples in the case of cement mixing ratio 5%, 10%.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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• pp.28-41
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• 2004

The study is aimed to assess the usefulness of the mixture design for spent resin immobilization in cement. Although a considerable amount of research has been carried out to determine the limits for the composition of an acceptable resin-cement mixture, no efficient experimental strategy exists that explores the full properties of waste form against composition relationship. In order to gain an overall view, this report introduces the method of mixture design and mixture analysis, and describes the design of experiment of the 5-component mixture with the constraint conditions. The mathematic models of 28-day compressive strength varying with the ingredients are fitted, and the main effect and interaction effect of two ingredients are identified quantitatively along with the graphical interpretation using the response trace plot and contour plots.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.205-210
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• 2000

This study concerns the cement-solidification. stabilization of the electric furnace dust. Compressive strength and leaching test of heavy metals were evaluated for varing types and ratios of cements and the effect of some additives of hauyne clinker and slag were also discussed. In this cases of using cement binders more than 30%, the compressive strength showed the values over 150kgf/cm2. so it can be used as filler for concrete precastings. Type III cement and Hauyne clinker improved the compressive strength, especially early strength. Leaching amount of heavy metals was decreased when using type III cement and adding hauyne clinker and slag. The values were especially low in the case of slag addition.

• 환경위생공학
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• 제16권1호
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• pp.53-60
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• 2001

In this study, the heavy metals in tannery sludge were solidified by using cement and power plant fly ash. Solidification characteristics were discussed with the compressive strength and chromium leaching characteristics of solids. The compressive strength of cement mortar was increased by the amount of fly ash up to 24.3~33.8%, which was considered the results of pozzolanic reaction. When the content of fly ash was 20%, cement mortar showed the highest value $295kg/\textrm{cm}^2$ for 28 days curing. At early curing days, solidified chromium tannery sludge solids were showed lower compressive strength because of the retard on the hydration of cement, but the compressive strength was recovered to be more than $140kg/\textrm{cm}^2$ for 28 days curing regardless with the amounts of fly ash. Also, the results of leaching tests by KSM and TCLP method were showed that the solidified chromium sludge have leached out 0.3~2.2% and 11~17%, respectively.

• 한국물환경학회지
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• 제25권3호
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• pp.404-410
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• 2009

In this study, research for physical and chemical characteristics were conducted through analysis of sediments, grading and heavy metals (e.g., Mn, Cu, Cd, Zn and Pb ) in sewers which are classified by drainage types. After that, cement solidification and yellow soil calcinations made heavy metals stabilized and then, ways of recycling it were examined. The grain size distribution of all sediments was relative graded. When evaluating heavy metal pollution through index of geoaccumulation (Igeo), Cu showed moderately pollution or strong pollution in forest and street site and Zn was assessed by moderately pollution in military, residential, and street site. Analysis of Pearson Correlation coefficient of heavy metal indicated that all items in street site have tight relationship respectively. Especially, Cd-Zn, Cu-Pb, Cu-Mn, and Pb-Mn have relationship at 99% confidence intervals in statistical analysis. Recycling it with cement solidification was satisfied with compressive strength standard under 55% deposit contents and Zn, Pb, Mn were stabilized effectively. If time and temperature plasticity and compressive strength would be standard, it is revealed that yellow soil calcinations is valuable aggregate when it has 50-60 Wt% contents. When considering economic feasibility and stabilization of heavy metals, cement solidification would be more appropriate than yellow soil calcinations as solution to recycling.

• 대한토목학회논문집
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• 제8권2호
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• pp.89-98
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• 1988

본 연구는 도금공장에서 생산된 슬러지를 시멘트 고형화방법을 이용하여 처리할 때 고형화에 영향을 미치는 인자들 중에 모래/시멘트 비, 물시멘트 비, 젖은 슬러지의 양, 그리고 중금속 용출방지제를 네가지의 인자로 하여 압축강도와 용출량의 변화를 살펴 보았다. 모래/시멘트 비는 Cr(VI) 용출에 가장 큰 영향을 미치는 인자이며, 물/시멘트 비는 Zn와 압축강도에 가장 큰 영향을 미치는 인자였다. Cr(VI)는 Zn보다 시멘트 고형화에서 leachability가 더 적었다. 현장에서의 Cr(VI)과 Zn 그리고 압축강도를 예측하기 위한 모델을 계발하였으며, 고체화의 3급 Brick으로의 이용을 위해 혼합조건을 제시하였다. 그리고 30g의 건조슬러지를 고형화할 때 최적조건은 모래/시멘트 비, 물/시멘트 비, 그리고 중금속 용출방지제의 양은 각각 1, 1.5, 1.075g이었다.