• Nuclear Engineering and Technology
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• 제30권1호
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• pp.1-7
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• 1998

Effects of pH, bentonite and Portland cement on the leaching of the simulated waste glass were investigated. The simulated waste glass showed the low leach rate in the neutral pH region, while the leach rate in both acidic and alkaline regions increased. Addition of bentonite to the leachant enhanced the leaching of the waste glass. When the waste glass was leached at 72$^{\circ}C$ for 36 days in the ground water with gel state Na-bentonite, approximately 2.2${\mu}{\textrm}{m}$ of the surface was corroded out and the large amount of Ti, Nd, and Zr was observed on the surface. The amount of B leached from the simulated waste glass in the presence of domestic bentonite was about three times higher than that in the presence of Aldrich bentonite as well as Portland cement.

• 한국세라믹학회지
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• 제26권4호
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• pp.521-531
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• 1989

The dependence of the chemical durability of simulated waste glasses containing the simplified waste similar to the SRP waste on compositions of host glasses, amounts of waste loading, and kinds of leachants has been investigated as a basic study on the waste immobilization through vitrification. The maximum limit of the amount of waste loading for glassforming with the host sodium borosilicate glasses selected in this study was 50wt%. The chemical durability of waste glasses whose host glass belonged to the immiscible composition region was much higher than that of waste glasses whose host glass belonged to the miscible composition region. The former waste glass showed lower chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in silicate water. It was also observed that the total leaching rates in brine were noticeably small in comparison with those in other solutions. The composition of the host borosilicate glass which was suitable for the treatment of the waste through vitrification was found to be 25 Na2O-5B2O3-70SiO2(wt.%).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.399-402
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• 2004

An aquifer thermal energy storage (ATES) model is simulated by FEFLOW according to the scenario of heat pump operation in two layered confining aquifer. The scenario is consisted of 4 steps: 90 days pumping (west well) and waste water injection (east well: 35 $^{\circ}C$), 90 day s stop, 90days pumping (east well) and waste water injection (west well: 5 $^{\circ}C$), and 95 days stop. The injection of the waste water is limited in the second layer and the first layer is aquitard. The temperature distribution at the surface shows low difference with reference temperature and opposit aspect with that of the second layer because the thermal transition through the first layer is very slow. Even though the simulated thermal transition in the aquifer system have a difference with real ATES system, optimal design and operate system can be developed with field tests and operational experience.

• 한국환경과학회지
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• 제12권6호
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• pp.583-591
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• 2003

The research on potential energy was conducted to conserve the high-exergy energy like primary energy and utilize waste heat from sewage. From the Point of view in using the waste heat, the energy Potential of waste water from the model house was simulated. From the results, when the heated water was supplied to the model house side in order to put unused energy to Practice use, heated water had higher energy Potential than unheated water, which was due to the discharge of most of unused energy. The possessing heat capacity of sewage from heated water was increased to 40-70 percents in comparison with that from the unheated water. Therefore, it can be used as energy source for improving coefficient of performance of heat pumps. By adopting the multiple heat pump into a model house, It showed that the possessing heat capacity of sewage was reduced. It was also found that the heat was recovered as energy source fur multiple heat pump in a model house.

• Journal of the Korean Wood Science and Technology
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• 제42권5호
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• pp.597-604
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• 2014

Laboratory-scale landfills (simulated landfills) were designed to determine the formaldehyde released into air and leachate from medium density fiberboard (MDF). Simulated landfills were constructed using cylindrical plastic containers containing alternating layers of soil and MDF for a total of five layers. The highest concentration of formaldehyde was found in the air and leachate from the MDF only treatment compared to treatments containing MDF and soil. At the end of the study (28 days), formaldehyde concentrations in air and leachate from treatments containing MDF and soil decreased by 70 percent and 99 percent, respectively, while the treatment containing MDF only still released formaldehyde into the air and leachate. Therefore, waste MDF after storing 4 weeks in water may be recycled as compost or mulch based on formaldehyde leaching. Also, these data indicate soil restricts formaldehyde release into air and leachate and provides new information about the fate of wood-based composite waste containing UF resin disposed in landfills.

• 한국산학기술학회논문지
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• 제14권8호
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• pp.4093-4099
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• 2013

본 논문은 부남호 부근에 대형 콘도를 지을 때 콘도에서 나오는 오폐수가 천수만 가두리 양식장 등에 영향을 미치는가에 관한 것이다. 대표적으로 COD를 모사하였으며, 다른 인자는 수치에 비례하여 예측할 수 있다. 조류의 이동 경로는 평균적으로 방류지점으로부터 서쪽을 향하게 되어 이곳은 가두리 양식장이 없기 때문에 비교적 안전하며, 바닷물이 정지한 상태를 가정하여 모의한 결과 매우 천천히 확산되는 것을 보았지만, 바람 등에 의한 흐름이 있을 경우는 오염물질의 확산을 촉진하여 쉽게 희석되기 때문에 오염물질에 의한 피해의 위험은 크지 않을 것으로 판단된다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.51-59
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• 2005

The long-lived fission product $^{99}Tc$ is present in large quantities in nuclear wastes and its chemical behavior in aqueous solution is of considerable interest. Under oxidizing conditions technetium exists as the anionic species $TcO_4^-$ whereas under the reducing conditions it is generally predicted that technetium will be present as $TcO_2{\cdot}nH_2O$. Technetium oxide was prepared by reduction of a technetate solution with $Sn^{2+}$. The concentration of total technetium and Tc(IV) species in the solutions were periodically determined by separating the oxidized and reduced technetium species using a solvent extraction procedure and counting the beta activity of the $^{99}Tc$ with a liquid scintillation counter. The experimental results show that the rate of oxidation of Tc(IV) in simulated groundwater and redistilled water is about $(1.49{\~}1.86){\times}10^{-9} mol/(L{\cdot}d$) under aerobic conditions, but Tc(IV) in simulated groundwater and redistilled water is not oxidized under anaerobic conditions. Under aerobic or anaerobic conditions the solubility of Tc(IV) oxide in simulated groundwater and redistilled water is equal on the whole.

• 한국토양비료학회지
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• 제29권2호
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• pp.130-136
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• 1996

EC(Electrical conductivity) meter를 이용(利用)하여 폐수(廢水) 처리제(處理劑)로 사용(使用)된 천연(天然) Zeolite의 교환시기(交換時期)를 쉽고 간편(簡便)하게 결정(決定)하고자 상징액(上澄液)의 EC변화(變化)와 Zeolite에 의한 이온의 흡착반응(吸着反應)과의 관계(關係)를 조사(調査)하였다. 용액중(溶液中)의 양이온이 Zeolite에 흡착(吸着)됨에 따라 상징액(上澄液)의 EC는 흡착평형(吸着平衡) 시(時)까지 감소(減少)하였으며 그 이후(以後)는 일정(一定)한 EC를 유지(維持)하였다. 시료량(試料量) 및 첨가용액(添加溶液)의 농도(濃度)가 증가(增加)할수록 $NH_4{^{+}}$와 $K^+$의 흡착량(吸着量)이 많아져서 용액(溶液)의 EC는 크게 감소(減少)하였다. Na-Zeolite가 Ca-Zeolite보다 $NH_4{^{+}}$와 $K^+$의 흡착량(吸着量)은 많았으나 $Na^+$의 탈착속도(脫着速度)가 $Ca^{2+}$ 보다 빠르고 용이(容易)하기 때문에 EC의 변화(變化)는 적었다. 실제(實際) 축산폐수(畜産廢水)에서도 Zeolite에 의한 흡착반응(吸着反應)이 진행(進行)됨에 따라 용액(溶液)의 EC가 감소(減少)하였고 그 경향(傾向)은 혼합한 용액(溶液)에서와 비슷하였다. 동일농도(同一濃度)의 용액(溶液)을 계속 첨가(添加)하여 반응(反應)을 조사(調査)한 결과(結果) 축산폐수와 혼합폐수 모두 4회(回)의 처리(處理)로 흡착포화상태(吸着飽和狀態)에 도달(到達)했으며 이때의 상징액(上澄液)의 EC는 첫 축산폐수(畜産廢水)의 EC와 같아졌기에 이때를 Zeolite 교환시기(交換時期)로 결정(決定)하여야 할 것이다.

• 상하수도학회지
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• 제7권2호
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• pp.9-23
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• 1993

Emission of hazardous and volatile organic chemicals from solid waste landfill site was become to important issue because of environmental pollution and health risk by such chemicals. Laboratory batch and continuous experiments were conducted respectively to elucidate isothermal sorption behaviors and transport phenomena(by gas through unsaturated solid waste layer) in wet solid waste-gas system. Source separated and size reduced refuse(bulky waste) and incinerated ash were used after controlling water content, and trichloroethylene(TCE) was chosen among many such chemicals because of it's generality among those man-created pollutants. Isothermal TCE sorption equilibria wet solid waste-gas system can be described in linear equation and partition coefficient in this system can be estimated approximately by the simple equation derived from schematic structure of the system. Transport equation modified by instantaneous equilibrium sorption fraction and kinetic sorption rate(overall mass transfer capacity coefficient) simulated well the column experiment results.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.21-31
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• 2003

IAEA, FT-04-020, ANS 16.1의 침출시험법을 각각 수행하여 얻은 시험결과를 이용하여 상호비교 평가하였다. 붕산을 함유한 파라핀 및 시멘트 고화체에서의 Co-60과 Cs-137의 침출지수는 6이상이었으나 고화매질과 탈염수의 종류에 따라 상반되는 침출거동을 보였다. 침출수로 합성해수와 탈염수를 사용하였을 경우 Co는 시멘트 고화체에서는 합성해수, 파라핀 고화체에서는 탈염수에서 침출이 높았다. 반면에 Cs의 침출정도는 시멘트에서는 탈염수, 파라핀에서는 합성해수에서 높았다. Co의 침출분율은 시멘트 고화체에서 IAEA > ANS > FT의 순으로 높았으며, 반대로 파라핀 고화체에서는 이의 역순이었다.