• 제목/요약/키워드: coal waste

검색결과 251건 처리시간 0.023초

석탄회를 재활용한 건설소재의 강도발현 및 건조수축 (Strength Development and Drying Shrinkage in Recycled Coal-Ash Building Material)

  • 조병완;김영진;박종빈
    • 콘크리트학회논문집
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    • 제15권5호
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    • pp.670-678
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    • 2003
  • 최근 폐기물 재활용에 대한 관심이 지대해 지기 시작하면서 많은 연구가 진행 중에 있다. 그 중 석탄회의 재활용 연구로는 시멘트 대체제로 및 고온소성법을 이용한 인공골재 개발등의 연구가 진행되었으나, 경제성에 있어서 부적합하였다. 본 연구에서는 비소성 고형화 기술을 사용하여 석탄회를 재활용한 건설재료의 토목, 건축 구조분야에 실용화하기 위한 기초자료를 제시하고자 한다. 재령에 따른 압축강도의 회귀분석을 하였고, 압축강도와 할선탄성계수를 구하였다. 그리고 Lineweaver와 Burk 방법을 적용하여 건조수축의 회귀분석을 실시하여 제안식을 도출하였다. 연구결과, 석탄회 경화체의 압축강도는 구조용 부재로 사용가능 한 수준이었으며 건조수축은 중용열 시멘트 모르터와 유사하였다. 또한, Bottom ash의 첨가가 석탄회 경화체 내부에서 골재의 역할을 수행하는 것으로 나타났다. 건조수축 양상을 중량감소율 측정결과와 종합하면 Bottom ash 치환율과 공시체 내부의 수분감소가 건조수축의 지배적인 요인임을 파악할 수 있었다. 또한 압축강도로부터 탄성계수를 추정하는 제안식은 본 연구에서의 압축강도 범위에서는 매우 높은 신뢰도를 보였다. 또한 Lineweaver와 Burk 방법으로 도출한 건조수축 추정 제안식도 매우 높은 신뢰도를 보였다.

산소/이산화탄소 농도 변화에 따른 석탄과 폐기물 연료의 순산소 연소 특성 (Oxy-combustion Characteristics of Coal and Waste Fuels with the Concentrations of Oxygen and Carbon Dioxide)

  • 강신욱;박정민;이상섭
    • 한국대기환경학회지
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    • 제33권5호
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    • pp.473-479
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    • 2017
  • This study was designed to understand characteristics of oxy-combustion of coal, dried sewage sludge and solid refuse fuel (SRF). Thermogravimetric analysis was conducted by burning the fuels with air, 21% oxygen ($O_2$)/79% carbon dioxide ($CO_2$) and 30% $O_2/70%$ $CO_2$. Heating rates were varied as 5, 10, 25, 40 and $100^{\circ}C/min$. Complete coal combustion was found at the heating rates of 5, 10, 25 and $40^{\circ}C/min$, and different combustion behavior was found with the gas composition at the heating rates of 10, 25, 40 and $100^{\circ}C/min$. Coal combustion with 30% $O_2/70%$ $CO_2$ showed the highest while coal combustion with 21% $O_2/79%$ $CO_2$ showed the lowest combustion rate. On the other hand, the combustion of dried sewage sludge and SRF showed similar combustion behavior with respect to the combustion gas composition. This suggests that oxy-combustion of dried sewage sludge and SRF which contain a large amount of volatile matter may show similar combustion behavior to their air combustion.

CO2 sequestration and heavy metal stabilization by carbonation process in bottom ash samples from coal power plant

  • Ramakrishna., CH;Thriveni., T;Nam, Seong Young;kim, Chunsik;Ahn, Ji Whan
    • 에너지공학
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    • 제26권4호
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    • pp.74-83
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    • 2017
  • Coal-fired power plants supply roughly 50 percent of the nation's electricity but produce a disproportionate share of electric utility-related air pollution. Coal combustion technology can facilitate volume reduction of up to 90%, with the inorganic contaminants being captured in furnace bottom ash and fly ash residues. These disposal coal ash residues are however governed by the potential release of constituent contaminants into the environment. Accelerated carbonation process has been shown to have a potential for improving the chemical stability and leaching behavior of bottom ash residues. The aim of this work was to quantify the volume of $CO_2$ that could be sequestrated with a view to reducing greenhouse gas emissions and stabilize the contaminated heavy metals from bottom ash samples. In this study, we used PC boiler bottom ash, Kanvera reactor (KR) slag and calcined waste lime for measuring chemical analysis and heavy metals leaching tests were performed and also the formation of calcite resulting from accelerated carbonation process was investigated by thermo gravimetric and differential thermal analysis (TG/DTA).

폐탄광지역 퇴적물의 중금속 존재형태 및 안정화에 관한 연구

  • 이정란;이재영;김휘중
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.253-259
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    • 2005
  • Mine is quickly decline, Nowadays, many of abandoned and closed mines. AMD is abandoned surface water by accumulated yellowboy and caused environmental pollution by amount of heavy metals. The aim of this study waste lime was mixed with the sediment to produce an aggregate far the purpose of neutralizing the acidity and stabilization the heavy metal in the aggregate structure .to pozzolan effect. The result of Waste lime and sediment mixed(5%, 10%, 20%)ration by curing days(3, 7, 38days), After 28 curing days as 5% mixed waste lime leaching solution concentration of all heavy metals is satisfied with regulation limit. Also, the result of fractionate heavy metals to stabilization as 28 curing days very decrease exchangeable and reducible type, and then increase carbonate type. With the above results, waste lime the most effective for the sediment treatment and useful for the recycling waste resource.

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석탄회를 재활용한 '셀카시'의 토양 개량과 골프 코스 잔디 생육에 대한 효과 (Effect of "CellCaSi" recycling Coal Fly Ash on Soil Amendment and the growth of Turfgrass in Golf Course)

  • 이상재;허근영;정운익
    • 아시안잔디학회지
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    • 제13권4호
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    • pp.191-200
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    • 1999
  • The objective of this study was to improve the recycling rate of coal ash fly, industrial waste. This study was conducted to analyze the physico-chemical properties of \"CellCaSi\" and clarify the effects on the growth of Kentucky bluegrass(Poa pratensis L.) and creeping bentgrass(Agrostis paulstris Huds \"Penncross\") and the chemical properties of soil, which was cellular calcium silicate reproduced by coal ash fly. A field assay was carried out in Young-Pyong Golf Course. The results were as follows. 1. The main chemical composition of CellCaSi was $SiO_2$(45~55%) and CaO(25~35), which was 70~90% of total weight. CellCaSi showed pH 8~9. Bulk density of CellCaSi was 0.35~0.45g/㎤. Water content of CellCaSi was 52.5~67.5%. 2. In the applied plots, leaf width, grass density per $1\textrm{cm}^2$, rhizome number and length per plant, and root number per plant of Kentucky bluegrass(Poa pratensis L.) and creeping bentgrass(Agrostis paulstris Huds \"Penncross\") showed increasing tendency compared with the control. The application of CellCaSi increased the growth of turfgrasses. Their visual quality on hardness, grass shoot density per $1\textrm{cm}^2$ and root growth was very good. And, their visual quality on rhizome growth was good. 3. After the application of CellCaSi, pH, CEC, Ex-cation of the applied soil showed increasing tendency with the little range, $SiO_2$content increasing tendency considerably, and organic matter content decreasing tendency compared with the control.ncy compared with the control.

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석탄과 폐기물 연료의 수은 및 중금속 배출 특성 (Emission Characteristics of Mercury and Heavy Metals from Coal and Waste Fuels)

  • 아흐마드 탄비어;박민;길상인;윤진한;박정민;이상섭
    • 자원리싸이클링
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    • 제26권2호
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    • pp.33-38
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    • 2017
  • 폐기물은 이차연료나 대체연료로 사용될 수 있다. 본 연구에서는 고형연료(SRF)와 건조 하수슬러지를 연소하여 배출되는 중금속 물질을 분석하였다. 석탄, SRF, 건조 하수슬러지의 구리(Cu), 크롬(Cr), 카드뮴(Cd), 니켈(Ni), 아연(Zn), 납(Pb), 비소(As), 수은(Hg) 함량을 조사하였고, 각 물질이 연소가스에서 가스상으로 존재하는 농도를 분석하였다. 실험결과, 가스상으로 배출되는 Cu, Cr, Cd, Ni, Zn, Pb의 양은 매우 적은 것으로 나타났다. 그러나 가스상 수은은 연소 배기가스에서 많은 양이 배출되었다. SRF는 연소 배기가스에서 높은 수은 산화도를 보였고, 건조 하수슬러지는 높은 수준의 수은 배출농도를 보였다.

Evaluating Efficiency of Coal Combustion Products (CCPs) and Polyacrylamide (PAM) for Mine Hazard Prevention and Revegetation in Coal Mine Area

  • Oh, Se Jin;Oh, Seung Min;Ok, Yong Sik;Kim, Sung Chul;Lee, Sang Hwan;Yang, Jae E.
    • 한국토양비료학회지
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    • 제47권6호
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    • pp.525-532
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    • 2014
  • Since mine wastes were merely dumped in the mine waste dump, they have produced acid mine drainage (AMD). Therefore, main objective of this study was to evaluate the effect of coal combustion products (CCPs) on heavy metal stabilization and detoxification for mine wastes. Total six treatments for incubation test were conducted depending on mixing method (completely mixing and layered). Also, lysimeter experiment was conducted to examine efficiency of polyacrylamide (PAM) on reduction of mine wastes erosion. Result of incubation test showed that concentrations of soluble aluminium (Al) and iron (Fe) in leachate decreased compared to control. The lowest soluble Al and Fe in leachate was observed in 50% mixed treatment (14.2 and $1.03mg\;kg^{-1}$ for Al and Fe respectively) compared to control treatment (253.0 for Al and $52.6mg\;kg^{-1}$ for Fe). The pH of mine wastes (MW) and leachate increased compared to control after mixing with CCPs and ordered as control (MW 6.4, leachate 6.3) < 10% (MW 7.7, leachate 7.1) < 20% (MW 9.0, leachate 7.8) < 30% (MW 9.5, leachate 8.3) < 40% (MW 9.9, leachate 8.5) < 50% (MW 10.5, leachate 8.6). Application of PAM, both in liquid and granular type, dramatically decreased the suspended solid (SS) concentration of CCPs treatments. Reduction of SS loss was ordered as MW70CR30L ($24.4mg\;L^{-1}$) > MW70CR30LPL ($6.7mg\;L^{-1}$) > NT ($3.1mg\;L^{-1}$) > MW70CR30M ($1.6mg\;L^{-1}$) > MW70CR30MPL ($1.1mg\;L^{-1}$) > MW70CR30PGM ($0.7mg\;L^{-1}$) > MW70CR30LPG ($0.5mg\;L^{-1}$) > MW70CR30MPG ($0.4mg\;L^{-1}$). Overall, application of CCPs can be environmental friendly and cost-effective way to remediate coal mine wastes contaminated with heavy metals. In addition, use of PAM could help to prevent the erosion coal mine wastes in mine waste disposal area.

울산지역 공단에서 발생되는 비산재를 이용한 제올라이트 합성 (Synthesis of Zeolite Using Discharged Fly Ash in an Industrial Complex in Ulsan)

  • 이창한;박종원
    • 대한환경공학회지
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    • 제33권5호
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    • pp.301-306
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    • 2011
  • 본 연구에서는 울산지역의 화력발전소 및 소각로에서 발생하는 비산재, 석탄계 비산재와 폐촉매를 이용하여 수열합성, 용융합성, 용융/수열합성법에 의해 제올라이트를 합성하였다. 석탄계 비산재(F-C1와 F-C2)와 폐촉매(F-W5)는 $SiO_2$$Al_2O_3$의 함량이 60.29~89.62 wt%이며, F-C1과 F-C2는 XRD 패턴 분석에서 quartz와 mullite를 포함하고 있었다. 석탄계 비산재와 폐촉매를 이용한 제올라이트 합성은 3가지 합성방법에서 모두 가능하였다. 석탄계 비산재와 폐촉매는 용융합성법에 의해 주로 Na-A형 제올라이트(Z-C1, Z-C2와 Z-W5)로 합성되었으며, 합성된 제올라이트(Z-C1 and Z-C2)는 비산재의 CaO 성분과 합성과정에서 첨가된 Na2CO3에 의해 불순물인 calcite 피크를 형성하였다.