• 대한환경공학회지
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• 제22권10호
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• pp.1747-1756
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• 2000

고정층 칼럼에 충진물질로 게껍질(Protunus trituberculatus)과 활성탄(Norit 0.8 SUPRA)을 사용하였다. 10 g의 활성탄만을 충진물질로 사용했을 때는 380 층부피 (bed volume)의 10 mg/L 납 함유 폐수를 처리했을 때 파과 현상 (breakthrough)이 일어났지만, 1 g의 게껍질을 10 g의 활성탄 칼럼에 첨가했을 때는 1520 층부피에서 파과 현상이 일어났다. 게껍질의 첨가로 인해서 활성탄 칼럼의 납 제거능이 증가하였다. 이러한 급격한 효율의 증가는 납의 흡착에 유용한 $CO_3{^{2-}}$ 파 $OH^-$ 이온이 증가한 것 때문으로 사료되었다. 여러 가지 분석 결과에 의하면 납 제거의 주된 메카니즘은 게껍질 속의 $CaCO_3$가 용해된 후 납과 반응하여 $Pb_3(C0_3)_2(OH)_2$ 형태로 활성탄의 표면에서 침천물을 형성하는 것으로 사료되었다. 납의 제거능은 유입 폐수 중의 납 농도가 10 mg/L에서 50 mg/L로 증가될 때 2배 정도 증가하였으나 유입 폐수의 pH가 5.0에서 3.0으로 감소할 때 약 40% 정도 효율이 감소하였다.

• 청정기술
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• 제16권4호
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• pp.277-283
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• 2010

Eosin Y는 식용색소와 염료로 사용되지만 유해한 독성 물질이다. 본 연구에서는 입상활성탄에 의한 eosin Y의 흡착특성을 조사하였다. 활성탄의 양을 고정한 상태에서 초기농도, 접촉시간, pH 및 흡착온도 등이 eosin Y의 흡착에 미치는 영향을 회분식 빛 흡착칼럼실험을 통하여 연구하였다. Eosin Y에 대한 활성탄의 흡착능은 pH 조절에 의해 크게 개선되었으며, pH=3에서 초기농도 10 mg/L의 99%를 제거할 수 있었다. 회분식 흡착실험을 통해 흡착등온선을 구한 결과 eosin Y의 흡착평형관계는 293~333K 범위에서 Freundlich식이 잘 적용되었다. 흡착등온식으로 부터 평가된 k와 ${\beta}$값은 각각 19.56~134.62, 0.442~0.678이었다. 고정층의 운전조건이 파괴곡선에 미치는 영향을 조사하였다. 층높이 3 cm, 유속 2 g/min에서 eosin Y의 유입농도가 10 mg/L에서 30 mg/L로 증가함에 따라 파괴시간은 470분에서 268분으로 감소하였으며, 층높이 3 cm, 유입농도 10 mg/L에서 eosin Y의 초기유속이 l 에서 3 g/min로 증가함에 따라 파괴시간은 272분에서 140분으로 감소하였다. 또한 층높이가 증가함에 따라 파괴시간도 증가하였는데, 흡착대의 길이는 비슷한 양상을 나타냈다.

• 자원ㆍ환경경제연구
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• 제21권3호
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• pp.519-542
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• 2012

본 논문은 EU ETS 기간 전과 후를 비교함으로써 탄소누출이 일어났는가를 실증적으로 분석하였다. 해외직접투자를 탄소누출의 지표로 활용하여 EU 11개국을 대상으로 한 1995년부터 2009년까지의 패널데이터를 이용하여 생산비용과 환경비용과의 패널 분석을 하였다. 시장 추구형 해외직접효과도 아울러 고려하여 해외시장잠재력도 아울러 고려하였다. 본 분석에 의하면 제조업을 대상으로 한 일부모형에서 탄소누출이 확인되었다. 하지만 다양한 모형에서 일관되게 확인되지 않아서 EU 배출권거래제를 전후하여 탄소누출이 뚜렷하게 일어났다고 단정하기는 힘들다. 비교적 데이터의 시계열이 짧음에도 불구하고 일부모형에서 탄소누출이 검증되었다는 사실을 볼 때 향후 국내 배출권거래제 도입시 우리나라도 탄소누출의 가능성을 염두에 두고 배출권거래제 제도를 설계해야 할 것이다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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• pp.377-380
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• 2002

Acoustic Characteristics of Nitrile Butadiene Rubber with Carbon Black ContentAcoustic and mechanical properties of Nitrile Butadiene Rubbers (NBR) with the variation of the carbon black content were investigated. NBR where the acrylonitrile content is $33\%$ based on the mole percent has been prepared with fixed sulfur content for vulcanization. Acoustic measurement of the prepared rubbers were peformed in the frequency region of $300\;\~\;1000\;kHz$. Their mechanical properties such as density, hardness were also measured. Increase of the carbon black content in the rubber resulted in enhancement of the mechanical property and linear increase of the sound speed as function of the carbon black content. Interestingly, attenuation of the sound speed was only affected by the existence of the carbon black and not by the amount of carbon black in the experiment range of this article. In this study, it was found that the amount of carbon black content in the NBR was correlated with the acoustic properties and can be estimated nondestructively by the measurement of the specific acoustic property.

• 한국환경과학회지
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• 제16권11호
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• pp.1279-1285
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• 2007

The activated carbon was prepared from waste citrus peels using NaOH. With the increase of NaOH ratio, iodine adsorptivity and specific surface area of the activated carbon prepared were increased, but activation yield was decreased. The optimal condition of activation was at 300% NaOH and $700^{\circ}C$ for 1.5 hr. For the activated carbon produced under optimal condition, iodine adsorptivity was 1,006 mg/g, specific surface area was $1,356 m^2/g$, and average pore diameter was $20{\sim}25{\AA}$. From the adsorption experiment for benzene vapor in fixed bed reactor, it was found that the adsorption capacity of activated carbon prepared from waste citrus peel was higher than that of activated carbon purchased from Calgon company. This result implied that the activated carbon prepared from waste citrus peel could be used for gas phase adsorption.

• Journal of Ecology and Environment
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• 제43권4호
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• pp.341-351
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• 2019

Background: Standing biomass, litter production, rate of litter decomposition, amount of litter on forest floor, and amount of soil organic carbon distribution were investigated from March 2016 to November 2018 in order to evaluate the ecosystem value through organic carbon distribution in the Pinus densiflora forest at Namsan, Seoul Metropolitan City. Results: The amount of organic carbon in the Pinus densiflora forest was 261.09 ton C ha^-1 during the research period, and fixed organic carbon in plant through net photosynthesis was 3.2 ton C ha^-1 year^-1. The organic carbon in plant was 62.77 ton C ha^-1 (24.04%), in litter on the forest floor was 3.65 ton C ha^-1 (1.40%), and in soil was 194.67 ton C ha^-1 (74.56%). The value of plant, litter on forest floor, and soil organic carbon distribution were each 6,277,000 won ha^-1, 365, 000 won ha^-1, and 19,467,000 won ha^-1. The value per ton of fixed organic carbon in plant through net photosynthesis was 320,000 won ha^-1 year^-1 and the value of ecosystem services stored in carbon in the Namsan forest ecosystem was about 26.1 million won ha^-1 for 3 years. Conclusions: The results of this study suggest that the pine forests of Namsan rapidly decompose leaves due to the high atmospheric temperature and accumulate a large amount of organic carbon in the soil to provide climate control regulatory service function.

• 한국세라믹학회지
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• 제20권2호
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• pp.166-172
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• 1983

In this study the sillicon-alloyed isotropic pyrolytic carbon was deposited in the tumbling bed from the pyrolysis of propane and silicon tetrachloride and investigated whether the silicon-alloyed isotropic pyrolytic carbon deposited in this study was usable as bionaterial or not. The silicon-allyed isotropic pyrolytic carbon was varied by controlling the process variables such as propane con-concentration and the argon flow rate flowing in to the silicon tetrachloride bubbler at a fixed reaction bed tempera-ture of 120$0^{\circ}C$ a rotation of reaction tube of 40 rpm a bed particle weight of 7.5 g and a total flow rate of 21/min; the propane concentration was varied from 10 to 70 and the argon flow rate flowing into the silicon tetrachloride bubble from 0 to 1000 cc/min. The results show that the silicon-alloyed isotropic pyrolytic carbon was obtained at all conditions investigated, . And then the alloyed silicon content is rangion from 7 to 14.5 wt%. The density and deposition rate of deposited silicon-alloyed isotropic carbon increased axxording to silicon content and propane concentration. And the apparent crystal-size(Lc) of pyrolytic carbon is not changed with silicon content. The density and apparant crystallite size are respec-tively in the range of 1.94 to 2.06 and 20 to 25$\AA$ It is shown that the silicon-alloyed isotropic pyrolytic carbon ob-tained in this experiment is usable as biomaterial.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
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• pp.117-123
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• 2004

The burning characteristics of interacting coal particles in a convective flow are numerically investigated at various Reynolds numbers. The transient combustion of 2-dimensionally arranged particles, both the fixed particle distances of 5 radii to 20 radii horizontally and 3 radii to 24 radii vertically, is studied. The results obtained from the present numerical analysis reveal that the transient flame configuration and retardation of particle temperature augmentation with the horizontal or vertical particle spacing substantially influence devolatilization process and carbon conversion ratio of interacting particles. Volatile release and carbon conversion ratio of the second particle with decreasing horizontal and vertical particle spacing decrease gradually, whereas those of the first particle with decreasing vertical particle spacing increases due to flow acceleration. When the vertical particle spacing is smaller than $6R_{o}$, volatile release and carbon conversion ratio of the second particle decrease greatly due to reduction of flame penetration depth.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.41-42
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• 2011

The purpose of this study is not only fixation of carbon dioxide using the cement-saturated solution by wet carbonating reaction but also evaluate the possibility of storage technology of Carbon dioxide. wet carbonation is reaction of CO₂ injection by CO₂ reactor. As a result of experiment, the carbon dioxide is fixed, and high-purity Calcium Carbonate is eluted.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.71-72
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• 2012

The purpose of this study is not only fixation of carbon dioxide using the cement-Paste solution's calcium ion by wet carbonating reaction but also quantitatively evaluate the possibility of storage technology of Carbon dioxide. wet carbonation is reaction of CO₂ injection by CO₂ reactor. As a result of experiment, the carbon dioxide is fixed, and high-purity Calcium Carbonate is eluted.