• 제목/요약/키워드: Embodied carbon

검색결과 21건 처리시간 0.028초

Synthesis of High Purity Carbon Nano Fibers and Hydrogen from Propane Decomposition

  • Hussain, S.Tajammul;Gul, Sheraz;Mazhar, M.;Larachi, Faical
    • Bulletin of the Korean Chemical Society
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    • 제29권2호
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    • pp.389-392
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    • 2008
  • High purity carbon nano fibers/tubes (CNF/Ts) which contain 97% pure graphitic carbon are prepared by a new catalytic method. These carbon nano fibers/tubes are ready to use without any further purification. The striking feature of this method is the production of carbon nano fibers/tubes of narrow distribution range. The developed catalytic method also produces pure hydrogen. An additional advantage of this catalytic method is that catalyst can be reused without reactivation. Ni:Cu catalyst system is embodied into SCHOTT-DURAN filter disc of large pore size (40-100 mm). Due to the production of hydrogen in the reaction catalyst stability is enhanced and deactivation process is considerably slowed down.

Beyond Net Zero - SOM's Urban Sequoia Building Concept and Technologies for Future, Regenerative Cities

  • Mina Hasman;Jiejing Zhou;Alice Guarisco;Nicholas Chan;Alessandro Beghini;Zhaofan Li;Michael Cascio;Yasemin Kologlu
    • 국제초고층학회논문집
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    • 제12권2호
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    • pp.121-128
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    • 2023
  • Cities cover only 3% of the planet's surface, yet they are responsible for more than 75% of the global emissions. Given the projected urban built area will double by 2060, the carbon emitted from cities will further increase. SOM proposes the Urban Sequoia concept, for buildings that go beyond 'net zero' and absorb carbon from the atmosphere. This concept combines multiple strategies, including the use of an optimised building form with a highly efficient structural system, modularized prefabrication techniques, holistic integration of facade, MEP and interiors' components, bio-based materials, and Direct Air Capture (DAC) technology, to reduce a 40-storey building's whole life cycle carbon emissions by more than 300% over a 100-year lifespan. Calculations of embodied carbon emissions are performed with SOM's in-house Environmental Analysis (EA) Tool to demonstrate the effectiveness of employing Urban Sequoia's design strategies in the design of new buildings using current technologies.

물리적으로 활성화된 플라이애쉬를 함유한 시멘트 및 복합체의 이산화탄소 배출량 평가 (Strength-based Evaluation of CO2 Emission for Cement and Composite Containing Mechanically Sctivated Fly Ash)

  • 순양;이한승
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.125-126
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    • 2021
  • Fly ash, has been widely used as one of the main supplementary cementitious materials (SCMs) in the world, to replace part of cement to significantly save energy and reduce greenhouse emission. Via mechanical activation, fly ash can replace more cement without impairing early age compressive strength. This study focuses on the strength-based evaluation of carbon dioxide emission for blended cement composite containing mechanically activated fly ash. Results indicate that under similar compressive strength, a prominent drop has been witnessed in embodied energy of binary cement and CO2 emission of the composite containing mechanically activated fly ash compared with those containing ordinary fly ash.

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배출규제가 탄소누출에 미치는 영향 분석 및 전망: 소비 관점의 탄소회계와 국경조치의 영향을 중심으로 (Emission regulation and the carbon leakage: the impact of the consumption based carbon accounting and the border adjustment measure)

  • 오인하
    • 자원ㆍ환경경제연구
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    • 제21권4호
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    • pp.851-891
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    • 2012
  • 본 연구는 배출규제가 탄소누출에 미치는 영향을 소비관점의 탄소회계와 국경조치의 영향을 중심으로 살펴보았다. 대표적으로 논의되는 국경조치인 탄소관세는 가장 포괄적일 경우 소비관점에서 계산된 제품에 내재된 탄소함율을 기반으로 계산되게 된다. 본 연구는 다지역 투입산출 모형과 연산가능 일반균형 모형 등의 방법론을 사용하여 소비관점의 탄소회계에 따른 우리나라의 위상변화와 여기서 계산된 탄소관세를 포함한 여러 국경조치가 적용될 때 탄소누출과 각국 경제에 미치는 영향을 관찰하였다. 이를 위해 정태적 글로벌 연산가능 일반균형 모형을 구축하였다. 코펜하겐 합의문을 기반으로 한 각국의 2020년 중기감축목표의 달성이 탄소누출에 미치는 영향과 국경조치를 포함한 여러 자국 산업 보호조치가 미치는 영향을 분석하였으며, 의무감축국가군 및 국경조치에 대한 다양한 시나리오를 설정하였다. 결과적으로 우리나라를 중심으로 한 정책적 함의를 제시하였다.

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초등학교 건축물의 생애주기 에너지사용량 및 이산화탄소 배출량 평가 (Evaluation of Life Cycle Energy Consumption and CO2 Emission of Elementary School of Buildings)

  • 지창윤;홍태훈;정재욱
    • 한국건설관리학회논문집
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    • 제17권3호
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    • pp.52-60
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    • 2016
  • 본 연구에서는 LCA 모델을 이용하여 8개 초등학교 건축물의 생애주기 에너지사용량 및 이산화탄소 배출량을 평가 분석하였다. 이를 위하여, 자재생산, 자재운송, 시공, 운영, 해체 폐기단계를 포함하는 건축물 생애주기에서의 에너지사용량 및 이산화탄소 배출량을 평가할 수 있는 LCA 기반의 평가모델을 정의하고, 모델을 이용하여 사례 건축물을 평가하였다. 40년의 운영기간을 가정하여 평가한 결과, 내재에너지(즉, 자재생산, 자재운송, 시공단계 에너지사용량의 합), 운영에너지, 해체 폐기에너지는 평균적으로 2,279, 11,182, 228 Mcal/m2로 산출되었다. 각 단계별 평균 이산화탄소 배출량은 604, 2,708, 60 kg-CO2/m2로 산출되었다. 평가결과는 생애주기 에너지사용량 및 이산화탄소 배출량의 약 17%가 자재생산, 자재운송, 시공단계에서 발생한다는 사실을 보여준다. 따라서 건축물의 에너지사용량 및 이산화탄소 배출량 감축 목표를 달성하기 위해서는 내재에너지 및 이산화탄소 배출량이 반드시 고려되어야 할 것이다. 게다가, 운영에너지는 지역에 따라 확연하게 구분되는 반면, 내재에너지는 지역에 따른 차이가 없는 것으로 나타났다. 따라서 운영단계의 에너지 사용량 편차를 줄이기 위해서는 지역에 따라 보다 상세하게 구분된 단열 기준이 제시되어야 할 것이다.

Process Performance and Bacterial Community Structure Under Increasing Influent Disturbances in a Membrane-Aerated Biofilm Reactor

  • Tian, Hailong;Yan, Yingchun;Chen, Yuewen;Wu, Xiaolei;Li, Baoan
    • Journal of Microbiology and Biotechnology
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    • 제26권2호
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    • pp.373-384
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    • 2016
  • The membrane-aerated biofilm reactor (MABR) is a promising municipal wastewater treatment process. In this study, two cross-flow MABRs were constructed to explore the carbon and nitrogen removal performance and bacterial succession, along with changes of influent loading shock comprising flow velocity, COD, and NH4-N concentrations. Redundancy analysis revealed that the function of high flow velocity was mainly embodied in facilitating contaminants diffusion and biosorption rather than the success of overall bacterial populations (p > 0.05). In contrast, the influent NH4-N concentration contributed most to the variance of reactor efficiency and community structure (p < 0.05). Pyrosequencing results showed that Anaerolineae, and Beta- and Alphaproteobacteria were the dominant groups in biofilms for COD and NH4-N removal. Among the identified genera, Nitrosomonas and Nitrospira were the main nitrifiers, and Hyphomicrobium, Hydrogenophaga, and Rhodobacter were the key denitrifiers. Meanwhile, principal component analysis indicated that bacterial shift in MABR was probably the combination of stochastic and deterministic processes.

상류부문 탄소세 도입의 경제적·환경적 효과 분석: 철강산업을 중심으로 (Analysis of the Economic and Environmental Effects of Upstream Carbon Tax: Focusing on the Steel Industry)

  • 김동구;손인성
    • 자원ㆍ환경경제연구
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    • 제32권1호
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    • pp.47-75
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    • 2023
  • 탄소국경조정제도(CBAM)를 입법 추진하는 EU에 비해, 미국의 탄소국경조정 정책화 관련 움직임은 아직 상대적으로 더디다. 그러나 최근에는 미국에서도 관련 법안이 제안되고 있고 연구기관을 중심으로 배출권거래제가 아니라 상류부문 탄소세를 도입하고 이에 기반한 탄소국경조정을 실시하는 방안에 대한 연구결과가 제시되고 있다. 따라서 본 연구에서는 이와 같은 형태의 상류부문 탄소세와 탄소국경조정을 국내에 도입했을 경우에 경제적·환경적 효과가 어떠할지에 대해서 살펴보았다. CO2톤당 3만 원의 상류부문 탄소세가 국내 화석에너지 순 공급량에 적용될 경우, 예상 탄소세 수익은 약 22조 9,961억 원으로 2019년도 우리 정부의 총 세입 402조 원의 약 5.7%에 해당하는 수준이었다. 또한, 한국에서 온실가스 배출량이 가장 많으며 해외 수출물량도 적지 않은 철강부문의 에너지 수급현황을 토대로 산정한 철강부문의 이산화탄소 내재량은 1억 622만 톤CO2이었다. 이 이산화탄소 내재량에 톤당 3만 원의 상류부문 탄소세가 그대로 철강부문의 생산원가에 전가되었다고 가정할 경우, 철강부문의 탄소세 부담은 약 3조 1,865억 원에 달할 것으로 추산되었다. 철강제품의 수출비중을 이용해 추산한 수출환급금 1조 1,599억 원을 공제하더라도 내수용 철강재에 대한 탄소세 순부담은 2조 266억 원에 달해 철강재의 가격상승요인으로 작용할 것으로 분석된다.

Compacted expansive elastic silt and tyre powder waste

  • Ghadr, Soheil;Mirsalehi, Sajjad;Assadi-Langroudi, Arya
    • Geomechanics and Engineering
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    • 제18권5호
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    • pp.535-543
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    • 2019
  • Building on/with expansive soils with no treatment brings complications. Compacted expansive soils specifically fall short in satisfying the minimum requirements for transport embankment infrastructures, requiring the adoption of hauled virgin mineral aggregates or a sustainable alternative. Use of hauled aggregates comes at a high carbon and economical cost. On average, every 9m high embankment built with quarried/hauled soils cost $12600MJ.m^{-2}$ Embodied Energy (EE). A prospect of using mixed cutting-arising expansive soils with industrial/domestic wastes can reduce the carbon cost and ease the pressure on landfills. The widespread use of recycled materials has been extensively limited due to concerns over their long-term performance, generally low shear strength and stiffness. In this contribution, hydromechanical properties of a waste tyre sand-sized rubber (a mixture of polybutadiene, polyisoprene, elastomers, and styrene-butadiene) and expansive silt is studied, allowing the short- and long-term behaviour of optimum compacted composites to be better established. The inclusion of tyre shred substantially decreased the swelling potential/pressure and modestly lowered the compression index. Silt-Tyre powder replacement lowered the bulk density, allowing construction of lighter reinforced earth structures. The shear strength and stiffness decreased on addition of tyre powder, yet the contribution of matric suction to the shear strength remained constant for tyre shred contents up to 20%. Reinforced soils adopted a ductile post-peak plastic behaviour with enhanced failure strain, offering the opportunity to build more flexible subgrades as recommended for expansive soils. Residual water content and tyre shred content are directly correlated; tyre-reinforced silt showed a greater capacity of water storage (than natural silts) and hence a sustainable solution to waterlogging and surficial flooding particularly in urban settings. Crushed fine tyre shred mixed with expansive silts/sands at 15 to 20 wt% appear to offer the maximum reduction in swelling-shrinking properties at minimum cracking, strength loss and enhanced compressibility expenses.

PVD방식을 이용한 NDLC 박막에서의 액정 배향 효과 (Liquid Crystal orientation on the NDLC Thin Film Deposited using physical deposition method)

  • 이원규;오병윤;임지훈;나현재;이강민;박홍규;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.301-301
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    • 2008
  • Ion beam (IB)-induced alignment of inorganic materials has been investigated intensively as it provides controllability in a nonstop process for producing high-resolution displays[1][2]. LC orientation via ion-beam (IB) irradiation on the nitrogen doped diamond like carbon (NDLC) thin film deposited by physical deposition method-sputtering was embodied. The NDLC thin film that was deposited by sputter showed uniform LC alignment at the 1200eV of the ion beam intensity. The pretilt angle of LC on NDLC thin films was measured with various IB exposure time and angle. The maximum pretilt angle were showed with IB irradiation angle of $45^{\circ}$ and exposure time of 62.5 sec, respectively. To show NDLC thin film stability in high temperature, thermal stability test was proceeded. The uppermost of the thermal stability of NDLC thin film was $200^{\circ}C$. In this investigation, the electro-optical (EO) characteristics of LC on NDLC thin film were measured.

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신재생에너지 적용기술이 저탄소녹색도시건설에 미치는 영향연구 (Study for the Design of Zero-carbon City through the Application of Renewable Energies)

  • 박영규;김정인;김갑철
    • 신재생에너지
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    • 제6권4호
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    • pp.15-29
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    • 2010
  • In order to make the best choice for $CO_2$ abatement using renewable energy technologies, it is important to be able to adapt these technologies on the basis of their sustainability, which may include a variety of environmental indicators. This study examined the comparative sustainability of renewable technologies in terms of their life cycle $CO_2$ emissions and embodied energy, using life cycle analysis. The models developed were based on case studies of bioenergy pilot plant in P city of Kyungki province. Final results were total emission of $CO_2$ in Pocheonsi is 670,041 $tCO_2$, around 500,877 $tCO_2$ for electricity and for heat generation, and 169,164 $tCO_2$ for transportation. When used $1,984\;m^3$/day of waste (pig manure etc.) and operated CHP with wood chips of 144,664 ton/year, the $CO_2$ emission in P city was left as is an emission of 449,274 $tCO_2$ and an abatement of $CO_2$ in this region was increased by 32.9%.