• 제목/요약/키워드: Waste Stabilization

검색결과 194건 처리시간 0.02초

Preparation and Electrochemical Characterization of Nitrogen-Doped Porous Carbon Textile from Waste Cotton T-Shirt for Supercapacitors (슈퍼커패시터용 폐면 티셔츠로부터 질소 도핑된 다공성 탄소 직물의 제조 및 전기화학 특성 평가)

  • Chang, Hyeong-Seok;Hwang, Ahreum;Lee, Byoung-Min;Yun, Je Moon;Choi, Jae-Hak
    • Korean Journal of Materials Research
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    • 제31권9호
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    • pp.502-510
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    • 2021
  • Hierarchically porous carbon materials with high nitrogen functionalities are extensively studied as high-performance supercapacitor electrode materials. In this study, nitrogen-doped porous carbon textile (N-PCT) with hierarchical pore structures is prepared as an electrode material for supercapacitors from a waste cotton T-shirt (WCT). Porous carbon textile (PCT) is first prepared from WCT by two-step heat treatment of stabilization and carbonization. The PCT is then nitrogen-doped with urea at various concentrations. The obtained N-PCT is found to have multi-modal pore structures with a high specific surface area of 1,299 m2 g-1 and large total pore volume of 1.01 cm3 g-1. The N-PCT-based electrode shows excellent electrochemical performance in a 3-electrode system, such as a specific capacitance of 235 F g-1 at 1 A g-1, excellent cycling stability of 100 % at 5 A g-1 after 1,000 cycles, and a power density of 2,500 W kg-1 at an energy density of 3.593 Wh kg-1. Thus, the prepared N-PCT can be used as an electrode material for supercapacitors.

Evaluation of the Stability of Geomembrane Liner System in Closed Waste Landfill (사용종료 폐기물 매립장의 멤브레인 차수시스템 안정성 평가)

  • Lee, Heung-Gil;Oh, Young-In
    • Journal of the Korean Geosynthetics Society
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    • 제9권1호
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    • pp.39-46
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    • 2010
  • Recently, the effective use of closed waste landfill nearby urban areas has been demanded, because of the lack of the usable land. However, the reuse of closed landfill is needed an adequate stabilization of liner system. But most of these places are consisted of steep slope and hence it is necessary to use the geosynthetics liners in there. Liner system of waste landfills is an important facility which prevents leachate outgoing from the landfills and also groundwater infiltrating from surroundings into the landfills. During the waste disposal stage, differential settlement and tensile stress of the geosynthetic materials could occur due to impact load of trucks and dozers, waste loads and weak foundation soils. In this study, the tensile strength and tracer test were performed to evaluate the stability of geomembrane liner systems. Based on the tensile strength test result of in-situ geomembrane sample, the yield tensile strength maintain the suitable strength by specification and current law. However, according to the tracer test, the damage of geomembrane liner was detected on sanitary landfill section.

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A study on the Structure of Turbulent Diffusion Flame Behind the Hollowed Flame Holder (중앙분공형 보염기 후류에 안정된 난류확산화염의 구조에 관한 연구(I))

  • Kang, I.G.;Lee, W.S.;Kim, T.H.;Lee, D.H.
    • Journal of Power System Engineering
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    • 제2권2호
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    • pp.13-19
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    • 1998
  • The purpose of study is to investigate the flame stability and Structure of turbulent diffusion flame behind the hollowed flame holder, which is located on the waste gas coming out from the test furnace. Fluctuating temperature and ion current measurement and their statistical treatment were used for the purpose. Three types of flame were stabilized and each of which were changed by adequate equivalence ration. And we found that have no periodicity near reacting zone.

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A Study on the Treatment of Distillery Wastewater by Single-phase and Two-phase Anaerobic Digestion (단상(單相) 및 2상(相) 혐기성(嫌氣性) 소화(消化)에 의한 주정폐수(酒精廢水) 처리(處理)에 관한 연구(硏究))

  • Choung, Young Kyoo;Rah, Seung Woo;Park, Joon Hwan
    • Journal of Korean Society of Water and Wastewater
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    • 제7권1호
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    • pp.5-12
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    • 1993
  • The objectives of this paper are to present data to illustrate how an advanced digestion process, two-phase digestion, can provide superior performance in terms of waste stabilization efficiency and net energy recovery. As the result, it is possible to separate enrichment cultures of acidogenic and methanogenic organisms in isolated environments by kinetic control involving manipulation of dilution rates. In single-phase digestion process, HRT and COD loading for effective operation were 14.29 days and 2.33kg $COD/m^3$ day, but two-phase digestion may be conducted efficiently at 7 days of HRT and 5.71kg $COD/m^3$ day of loading. Data from this studies showed that the two-phase process is better than single-phase digestion under all test conditions when compared on the bases of gas yield and production rate, reductions of COD and VS, buffer capacity, and unconverted volatile acids in the effluent.

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A Study on the Structure of Turbulent Diffusion Flame Behind the Hollowed Flame Holder(II) (중앙분공형 보염기 후류에 안정된 난류확산화염의 구조에 관한 연구(II))

  • Kang, I.G.;Lee, W.S.;Moon, J.K.;Lee, D.H.
    • Journal of Power System Engineering
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    • 제3권3호
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    • pp.29-35
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    • 1999
  • The purpose of study is to investigate the flame stability and structure of turbulent diffusion flame behind the hollowed flame holder, which is located on the waste gas coming out from the test furnace. PDFs and Power Spectra technique of fluctuating temperature and ion current measurement were needed for this purpose. We discussed that the three types of stabilized flames were found as the result of post study. In this paper, we established the stability mechanism near the flame holder.

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매립지 잔류토사에서 DEHP의 흡착특성에 관한 연구

  • Jeong In-Ho;Lee Jae-Yeong;O Byeong-Taek
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.143-148
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    • 2005
  • Plastics and vinyl resin is generally used in the various fields of industry and daily life. Except incineration, most waste has been disposed finally in landfill and the leaching of plasticizer as DEHP(di 2-ethylhexyl phthalaet) has been taken place in the landfill. DEHP had been found. for endocrine disrupter by World Wild Life Fund and Japan. In this study aimed at estimation of capacity of adsorption and measurement of phthalate ester in the residual soil. The residual soil had been gathered from three closed landfill which was under stabilization with sorting and transferring. The Dibutyl phthalate and DEHP had been contained in all residual soil. Especially, resisual soil contained DEHP much more than peripheral soil. In J landfill residual soil, organic matter content, CEC and #200 sieve passing ratio is highest, and Freundlich isotherm sorption coefficient(K) and constant(1/n) is highest.

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Development of Common Reinforced Concrete Block for Slope Protection (사면보호용(斜面保護用) 범용보강(凡用補强)콘크리트블록의 개발(開發))

  • Ryu, Neung-Hwan
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 한국농공학회 2005년도 학술발표논문집
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    • pp.404-409
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    • 2005
  • The reinforced concrete blocks for reinforced earth layer are combined with soil structures consisted of facing unit, reinforcing materials and soil. Those environmentally friendly facing units of reinforced concrete blocks are made of mine waste and tailing and that will be played a role of the effects of recycling use of wasted resources. The block are consisted of three types as curved or straight in order to control topography. The systems are also not limited to wall hight so that they are effectively used for protecting the slope of banking and cutting of earth works. The reinforced concrete blocks developed this time will be effectively applied for not only retaining wall, road, park, golf course, public office building constructions but also protecting of slope stabilization projects.

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The Simulation of LES Model For Premixed Combustion around A Bluff Body (LES 모델을 적용한 Bluff-body 주위의 예혼합 연소 해석)

  • Jung, Eui-Man;Ku, Ja-Yeo
    • Journal of Aerospace System Engineering
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    • 제3권4호
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    • pp.41-49
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    • 2009
  • This paper present result of numerical simulation of premixed combustion around a triangle Bluff Body. And a numerical simulation of a premixed flame stabilization by a bluff body was performed using LES Model. The calculated results from the LES showed a good agreement with experiment data than k-model. Premixture combustion has flammability limit, quenching distance, smallest ignition energy has the combustion quality of the back. Bluff body makes a recirculation zone. Therefor velocity of behind bluff body is very slow. It was caused by slowly position speed and the fire occurred after the Bluff Body. Occurrence of fire it made the waste gas of high speed and the thrust made well.

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Case Study of Remidation and Investigation of Closed Unsanitary Landfill for Prevention of Leachate (비위생매립지 정밀조사 및 침출수 방지를 위한 정비방안 연구)

  • Kim, Sangkeun;Lee, Yongsoo
    • Journal of the Korean GEO-environmental Society
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    • 제13권1호
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    • pp.5-13
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    • 2012
  • For the last decade the amount of waste has rapidly been increased in South Korea and many waste landfills have been built according to government guidelines specifying required systems such as landfill liner, leachate collecting facilities, final cover system, etc. This effort has led the recently constructed landfills to be under well managed sanitary condition. In a meanwhile closed waste-landfill sites in the past before the adoption of the government guidelines exits under unsanitary condition. In these cases untreated leachate flew out to the surroundings due to the absence of liner and leachate collecting facilities and caused groundwater and soils to be contaminated. Waste generated odor and gas also brought civil complaints. Because environmental influences bring serious problems nearby sites, it is required to have unsanitary waste-landfills to be appropriately treated and managed. A study to evaluate environmental influence and contamination level of surroundings nearby and on the unsanitary landfills is necessary before the establishment of "Management guide of closed landfill site." This paper presents an environmental evaluation for the closed site, Doil-dong landfill, according to "Closed landfill management regulation" by Ministry of Environment. "D" landfill, located in Pyeongtaek city, has possobility to contaminate surrounding surfacewater and groundwater by leakage of leachate. The in-situ stabilization carried out to build the DMW(deep soil mixing cutoff wall) wall and drainage systems.

A study on the Recovery of waste fluids of the conservation treatment of waterlogged wooden artifacts (수침목재유물보존처리 폐액의 재활용에 관한 연구)

  • Yang, Seok-Jin;Kim, Jong-Hwa;Song, Ju-Yeong;Lee, Soo
    • Journal of the Korean Applied Science and Technology
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    • 제29권1호
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    • pp.108-115
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    • 2012
  • Archaeological waterlogged woods found under the sea, in lakes, or in swamp environments are generally weak and fragile. If waterlogged wood materials were taken out of the water and left without modification, they would collapse and lose their original dimensions completely. Conservation is performed to replace the water with chemical agents and to give dimensional stabilization and durability. EDTA and PEG are the most commonly used in the preservation of wood. pH control-precipitation method is used for recovery of EDTA from waste fluid of archeological waterlogged wood conservation treatment. The black substance is eliminated from wood as Fe-EDTA complex are formed and EDTA is separated and precipitated from Fe-EDTA complexes at pH 2.68 or less. The result of analysis of the precipitated products and the commercial EDTA by FT-IR and FE-SEM showed that precipitated product by pH adjusted was not a type of Fe-EDTA complex, but pure EDTA. Waste fluid produced in PEG treatment shows the black color and has an offensive odor by organic matter extracted from wood. Color of waste fluid is decolored with oxidation reaction by peroxy hydrate. In FT-IR and SEM-EDX of PEG after freeze-drying process, no significant change of functional groups induced from oxidation is observed, and any metal ion does not exist in the solid PEG specimen. The molecular weight of PEG is measured using GPC and viscometry. Properties of PEG before and after preservation treatment, and after oxidation with $H_2O_2$ were not changed. Consequently, the peroxidation with $H_2O_2$ is a reasonable and simple method to decolor the used PEG solution.