• 공업화학
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• 제25권1호
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• pp.103-106
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• 2014

생활폐기물 소각시설에서 발생하는 바닥재는 높은 염소함량과 불순물 때문에 재활용에 한계가 있다. 하지만 종량제봉투의 도입과 음식물폐기물의 직매립 금지, 생산자책임제도의 도입 등 다양한 제도의 개선을 통해 성상이 변화되고 있다. 최근의 생활폐기물은 수분함량과 염소함량이 낮고 발열량이 높은 특성을 보이는데 이는 음식물폐기물의 분리배출, 폐기물의 전처리를 통한 불연물의 분리, 염소 등이 함유된 PVC 분리 등에 기인한 것으로 볼 수 있다. 본 연구의 목적은 이러한 제도, 특히 음식물폐기물의 분리배출 등의 정책 도입에 따른 생활폐기물 소각시설의 바닥재 성상변화 특성을 분석하고 이를 토대로 바닥재의 재활용 가능성을 평가하는 것이다. 바닥재에 함유된 다양한 성분 중 시멘트 클링커의 주요 성분인 CaO는 2001년 26.7%에서 2006년 34.0%로 증가하였고, 염소성분은 2001년 1.84%에서 2006년 0.00655%로 큰 폭으로 감소하였는데 이는 석탄 화력발전소에서 발생하는 비산재의 특성에 근접하는 것으로서 시멘트 클링커의 원료물질 등 재활용 가능성을 가지게 된 것으로 판단할 수 있다.

• Journal of Microbiology
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• 제44권6호
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• pp.600-606
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• 2006

Spore forming actinobacteria (sporoactinobacteria) isolated from soils with an acidic pH in Pinus thunbergii forests and coal mine waste were subjected to taxonomic characterization. For the isolation of acidophilic actinobacteria, acidified starch casein agar (pH adjusted to 4-5) was used. The numbers of actinobacteria growing in acidic media were between $3.2{\times}10^4$ and $8.0{\times}10^6$ CFU/g soil. Forty three acidophilic actinobacterial strains were isolated and their 16S rDNA sequences were determined. The isolates were divided into eight distinctive phylogenetic clusters within the variation encompassed by the family Streptomycetaceae. Four clusters among them were assigned to the genus Streptacidiphilus, whereas the remaining four were assigned to Streptomyces. The clusters belonging to either Streptomyces or Streptacidiphilus did not form a monophyletic clade. The growth pH profiles indicated that the representative isolates grew best between pH 5 and 6. It is evident from this study that acidity has played a critical role in the differentiation of the family Streptomycetaceae, and also that different mechanisms might have resulted in the evolution of two groups, Streptacidiphilus (strict acidophiles) and neutrotolerant acidophilic Streptomyces. The effect of geographic separation was clearly seen among the Streptacidiphilus isolates, which may be a key factor in speciation of the genus.

• Advances in concrete construction
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• 제2권1호
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• pp.29-37
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• 2014

Increasing emphasis on energy conservation and environmental protection has led to the investigation of the alternatives to customary building materials. Some of the significant goals behind understaking such investigations are to reduce the greenhouse gasemissions and minimize the energy required formaterial production.The usage of concrete around the world is second only to water. Ordinary Portland Cement (OPC) is conventionally used as the primary binder to produce concrete. The cement production is a significant industrial activity in terms of its volume and contribution to greenhouse gas emission. Globally, the production of cement contributes at least 5 to 7 % of $CO_2$. Another major problem of the environment is to dispose off the fly ash, a hazardous waste material, which is produced by thermal power plant by combustion of coal in power generation processes. The geopolymer concrete aims at utilizing the maximum amount of fly ash and reduce $CO_2$ emission in atmosphere by avoiding use of cement to making concrete. This paper reports an experimental work conducted to investigate the effect of curing conditions on the compressive strength of geopolymer concrete prepared by using fly ash as base material and combination of sodium hydroxide and sodium silicate as alkaline activator.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.5-21
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• 2005

Urbanization rates of population range from about 1% in the developed countries to about 4% in developing countries. For a global population that may reach 10 billion within the next 40 years, pressure has arisen for an increase in the large-scale use of wastes and byproducts in construction. Ironically, most of the wastes that need to be recycled are generated in large cities where the need for constructed facilities to serve large population is high. Waste and recycled materials (WRM) that are used in construction are required to satisfy material strength, durability and contaminant teachability requirements. These materials exhibit a wide variety of characteristics owing to the diversity of industrial processes through which they are produced. Several laboratory-based investigations have been conducted to assess the pollution potential and load bearing capacity of materials such as petroleum-contaminated soils, coal combustion ash, flue-gas desulphurization gypsum and foundry sand. For full-scale systems, although environmental pollution potential and structural integrity of constructed facilities that incorporate WRM are interrelated, comprehensive schemes have not been developed for integrated assessment of the relevant field-scale performance factors. In this presentation, a framework for such an assessment is proposed and presented in the form of a flowchart. The proposed scheme enables economic, environmental, worker safety and engineering factors to be addressed in a number of sequential steps. Quantitative methods and test protocols that have been developed can be incorporated into the proposed scheme for assessing the feasibility of using WRM as partial or full substitutes for earthen highway materials in the field.

• 연구논문집
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• 통권23호
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• pp.93-107
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• 1993

The chemistry and performance characteristics of the EBDS process have been introduced, in which experimental results from laboratory, test plant, and pilot plant studies agree very well and can be understood from detailed kinetic models. The parametric dependencies of the NOx and $SO_2$, removal yields on the input conditions have been discussed and formulated quantitatively. The process is best suited for flue gas with high $SO_2$, loadings. The operation conditions, such as dose, ammonia, and water additions, can be adjusted fast upon load changes. The process works waste water free and the major product is a mixture of ammonium nitrate and sulfate that can be used as fertilizer. The up-date results show that the EBDS technology is safe and competitive with other already well-established technologies. Due to these interesting features, the electron beam process has gained much international recognition. Demonstration units of 100MW have been proposed in the United States and Japan. Further pilot plants are under construction in Poland and China, countries that make abundant use of highsulfur coal. Additional research activities are under way to further improve the energy efficiency of process, and accelerator prices have been decreasing during the past 10 years. So the EBDS process has a good chance to start a new generation of emission-control technology.

• 한국대기환경학회지
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• 제33권4호
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• pp.333-341
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• 2017

Recently, the earth has shown the limit of environmental capacity. It is also experiencing an environmental crisis with rising energy prices and depletion of coal. Therefore, development of renewable energy is very important solution. However, waste fuel solid are renewable fuels, but they cause environmental problems. In this study, the emission characteristics of hazardous air pollutants were analyzed through measurements at the facilities using solid fuels (SRF, BIO-SRF). Analysis method of PAHs are based on the Korea Standard Methods for Examination. The analysis of PAHs showed that the concentration much higher in Naphthalene, and Benzo(a)pyrene showed at a higher concentration incertain sources. As a result of gas phase and particle phase PAHs, most of Benzo(a)pyrene appeared to be particulate. Through the results of this study will provide basic data for atmospheric environmental management.

• 기술사
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• 제45권4호
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• pp.47-56
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• 2012

석탄합리화정책에 따라 많은 가행 광산들이 폐광을 하게 되고 이러한 폐광산들이 오랜 기간동안 방치되면서 폐광주변에는 지반침하, 침출수배출, 경관 훼손등의 환경오염을 수반하게 된다. 정부차원에서 여러 환경오염 방지대책이 진행중이나 이러한 환경오염 방지대책은 대부분 생태보호적인 관점에서 관심의 대상되어 왔고 우리가 이용하는 사회 인프라시설에 대한 영향은 상대적으로 소홀히 되어 왔다. 광산은 대부분 산악에 위치하며 이러한 위치조건상 폐광산 주변 중요 인프라시설로는 터널이 있을 수 있다. 이에 본 논고에서는 폐광산의 대표적 오염원인 광산폐수가 주변의 공용중인 터널에 미치는 영향의 종류와 사례에 대해 소개하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1018-1031
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• 2010

In order to investigate the applicability and suitability of the industrial by-products to landfill final cover, field pilot-scale lysimeter experiments were carried out. The mixture of loamy soil, bottom ash, and construction waste was placed as a cover material in lysimeter($2m{\times}6m{\times}1.2m$) which were constructed with cement brick, and then, volumetric water contents, pF value, and the quantity of runoff and seepage of treatment boxes filled with the mixture of loamy soil and the industrial by-products were monitored from July, 2007 to February, 2008. Among the cases tested, consequently, the case containing the mixture of bottom ash and loamy soil was most effective in engineering and hydrological properties and water retention ability.

• Geomechanics and Engineering
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• 제3권3호
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• pp.219-231
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• 2011

Waste fills resulting from coal mining should consist of large, free-draining sedimentary rocks fragments. The successful performance of these fills is related to the strength and durability of the individual rock fragments. When fills are made of shale fragments, some fragments will be durable and some will degrade into soil particles resulting from slaking and inter-particle point loads. The degraded material fills the voids between the intact fragments, and results in settlement. A laboratory program with point load and slake durability tests as well as thin section examination of sixty-eight shale samples from the Appalachian region of the United States revealed that pore micro-geometry has a major influence on degradation. Under saturated and unsaturated conditions, the shales absorb water, and the air in their pores is compressed, breaking the shales. This breakage was more pronounced in shales with smooth pore boundaries and having a diameter equal to or smaller than 0.060 mm. If the pore walls were rough, the air-pressure breaking mechanism was not effective. However, pore roughness (measured by the fractal dimension) had a detrimental effect on point load resistance. This study indicated that the optimum shales to resist both slaking as well as point loads are those that have pores with a fractal dimension equal to 1.425 and a diameter equal to or smaller than 0.06 mm.

• 에너지공학
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• 제9권3호
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• pp.228-236
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• 2000

본 연구에서는 순간 고온식 tubing-bomb reactor를 사용하여 41$0^{\circ}C$에서 Alaska산 아역청탄, 폐타이어, 폴리프로필렌 혼합물의 공동액화 시 액화특성 및 상승효과를 연구하였다. 석탄, 폐타이어와, 폴리프로필렌의 조성을 변화시키고 수소공여용매인 tetralin의 양을 변화시켜가며 공동액화를 진행했을 경우 공동액화율을 살펴보면, 무촉매 반응의 경우 폴리프로필렌의 양이 많아지면 tetralin이 첨가되지 않았을 경우 액화율이 증가하였으나 tetralin이 첨가되었을 경우 공동액화율이 감소하였다. 촉매 반응의 경우에는 모든 반응조건에서 상승효과가 나타났으며 폴리프로필렌의 양이 증가할수록 공동액화율이 증가하여 석탄 : 폐타이어 : 폴리프로필렌의 조성이 1:1:3에서 tetralin 4$m\ell$, Co-naphthenate 촉매 사용하였을 때가 최적의 반응조건으로 83%의 공동액화율을 나타내었다.