• 한국물환경학회지
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• 제23권2호
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• pp.222-227
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• 2007

The adsorption features of fluoride ion on the oyster shell have been investigated for the purpose of the employment of waste oyster shell as an adsorbent for the treatment of fluoride ion-containing wastewater. The major component of oyster shell was examined to be Ca with minor components of Na, Si, Mg, Al, and Fe. As the initial concentration of fluoride ion was raised, its absorbed amount was enhanced at equilibrium, however, the adsorption ratio of fluoride ion compared with its initial concentration was shown to be decreased. Also, adsorption of fluoride ion onto the oyster shell resulted in the formation of $CaF_2$ in the morphological structure of adsorbent. Kinetic analysis showed that the adsorption reaction of fluoride ion generally followed a second order reaction with decreasing rate constant with the initial concentration of adsorbate. Freundlich model agreed well with the adsorption behavior of fluoride ion at equilibrium and the adsorption reaction of fluoride ion was examined to be endothermic. Several thermodynamic parameters for the adsorption reaction were calculated based on thermodynamic equations and the activation energy for the adsorption of fluoride ion onto oyster shell was estimated to be ca. 13.589 kJ/mole.

• 한국물환경학회지
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• 제23권3호
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• pp.314-318
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• 2007

The feasibility of the employment of waste oyster shell as an adsorbent for fluoride ion has been tested by considering the effect ionic condition on the adsorption of fluoride ion on oyster shell. The adsorption capacity of oyster shell for fluoride ion was found not to be significantly influenced by the ionic strength of aqueous environment. The existence of complexing agent such as nitrilotriacetic acid in wastewater decreased the adsorbed amount of fluoride ion by forming a stable complex of $CaT^-$ and the adsorption reaction of fluoride ion on oyster shell was examined to be endothermic. The coexisting heavy metal ionic adsorbate in wastewater hindered the adsorption of fluoride ion, however, its adsorbed amount was increased as the particulate size of adsorbent was decreased. Finally, a serial adsorption column test has been conducted for a practical application of adsorption process and the breakthrough of the column adsorption was observed in 22 hours under the experimental condition.

• 자원리싸이클링
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• 제16권3호
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• pp.12-18
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• 2007

수산물 처리과정중에서 다량으로 발생하는 폐굴껍질을 흡착제로 활용하는 방안을 모색하고자 이의 물성을 분석하였다. 폐기되는 굴껍질의 조성은 대부분 $CaCO_3$인 것으로 나타났으며 온도를 증가시키면서 굴껍질을 열분해를 시키면 온도에 따라 수분과 $CO_2$에 의한 분해가 일어나 약 46%의 무게 감량을 보인다. pH가 증가할수록 흡착되는 불소 이온의 양은 크게 감소했다. 또한 산성 불소 폐수가 흡착 반응의 평형에 도달하였을 경우 굴껍질에서 용해된 ${CO_2}^{3-}$의해 중화되는 경향이 관찰되었다.

• 공업화학
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• 제19권4호
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• pp.439-444
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• 2008

폐각 원료를 수증기 활성화 공정을 거쳐 다공성 흡착제로 제조하여 흡착성능을 평가하였다. 세척 파쇄한 폐각원료를 $600{\sim}1000^{\circ}C$로 탄화시킨 후 $700{\sim}800^{\circ}C$의 회전로에 주입하는 수증기 활성화법에 의해 활성화공정을 수행하였다. 다양한 조건으로 제조된 폐각흡착제 중 $1000^{\circ}C$로 탄화시켜 제조된 흡착제가 다른 공정으로 제조된 흡착제에 비해 흡착능이 높게 나타났다. 또한 기상흡착과 액상흡착실험을 통해 흡착제로서의 활용가능성을 확인한 결과 기상흡착의 경우에는 기존 흡착제에 비해 현저히 떨어진 성능을 나타내었으며, 액상흡착의 경우에는 흡착질로 benzene을 선정한 경우 다른 상용 흡착제와 비교하여 거의 유사한 흡착특성을 나타내어 흡착제로서의 활용가능성을 확인할 수 있었다.

• Journal of Advanced Marine Engineering and Technology
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• 제32권3호
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• pp.387-393
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• 2008

This paper has dealt with the probability of oyster shell desiccant cooling system driven by renewable energy of photo-volatic effect with fundamental experiment. The test materials for desiccant are activated charcoal, silica-gel, hi-dry, and oyster shell. The experiments were mainly performed with focusing on the observation of surface features, adsorption amounts of the adsorbent species, and the effect of temperature. Oyster shell has sufficient probability for using as desiccant in a air-conditioning system. Moreover, the heat releasing device would be attached in the system, the system based with oyster shell can be operated with high efficiency.

• 한국세라믹학회지
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• 제47권6호
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• pp.524-528
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• 2010

In this study, the structure and properties of waste oyster shell and its phosphorus removal efficiency were investigated. Waste oyster shells are troublesome environmental waste in the coastal region where the oysters are produced. Waste oyster shells were pyrolyzed by bench-scale rotary kiln for its activation. It shows maximum 76% of phosphorus removal efficiency for the municipal wastewater and livestock wastewater. We found that the activated oyster shells can be used as a phosphorus removal agent with the consideration of high efficiency, easy processing, and cost effectiveness.

• 한국환경보건학회지
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• 제22권3호
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• pp.81-87
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• 1996

The purpose of this research is to examine the utilization of oyster shells for neutralization and removal of heavy metal ions in plating wastewater, because oyster shells have been known to be very porous, to have high specific surface area and to have alkaline minerals such as calcium and magnesium. The results obtianed from this research showed that oyster shells had a buffer capacity to neutralize an acidic.alkali system in plating wastewater. Generally, it could be showed that the removal efficiencies of heavy metal ions were very influenced by reaction times and oyster shell dosages. In point of ocean waste, if oyster shells substituted for a valuable adsorbent such as actviated carbon, they could look forward to an expected economical effect.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.431-434
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• 2003

Environmental pollution problems due to the wastes from various industrial facilities and activities have become a serious issue. The specific problem associated with heavy metals in the environment is their accumulation in the food chain and their persistence in nature. Present work investigates the possible uses of by-products for the removal of heavy metal ions. Heavy metals used in these studies were cadmium, lead and copper. Experiments were conducted with by-products such as oyster shell and fly ash to evaluate their sorption characteristics. The results of the study indicate that oyster shell can be properly used as an adsorbent for heavy metals because of its outstanding removal rate.

• 대한환경공학회지
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• 제35권7호
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• pp.525-531
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• 2013

대하천의 조류문제에 대한 해결책을 찾기 위해 다목적 여과저류지를 활용하는 방안을 연구하였다. 문헌조사를 통해 용존 인의 흡착제거에 우리나라에서는 굴패각이 적합함을 알 수 있었고, 이를 흡착제로 활용한 등온흡착실험과 칼럼실험을 수행하였다. 등온흡착실험결과 흡착에 의해 하천수의 용존 인을 모두 제거하여 대하천에서의 조류발생을 방지하는 것은 어렵다는 것을 알 수 있었고, 칼럼실험결과 제한적인 조건에서는 굴패각을 흡착여재로 활용하는 방안이 가능함을 알 수 있었다. 실험결과를 근거로 이미 발생한 조류를 여과저류지를 이용하여 제거하는 방안을 제시하였으며, 인공하천의 하상표층에 형성된 슬러지 케익을 기계적으로 제거하여 하류의 농축부에 모아 최종제거하고 또한 농축부에서 흡착재로 굴패각을 사용함으로써 농축부의 사멸조류에 의한 인의 재방출을 억제하는 것이다.

• 한국환경과학회지
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• 제15권11호
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• pp.1053-1059
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• 2006

This study was performed to investigate the possible uses of waste sludge for the removal of heavy metal ions. The adsorption experiments were conducted with wastes such as sewage treatment sludge, water treatment sludge and oyster shell to evaluate their sorption characteristics. Heavy metals selected were cadmium, copper and lead. in the sorption experiments on the sewage treatment sludge, water treatment sludge, oyster shell and soil, sorption occurred in the beginning and it reached equilibrium after 40 minutes on the oyster shell and 4 hour on the sewage treatment sludge and water treatment sludge. Results of Freundlich isotherms indicated that sewage treatment sludge could be properly used as an adsorbent for heavy metals and sorption strength of heavy metals was in the order of Pb > Cu > Cd. In the influence of pH on the adsorbents, sorption rate was more than 80% in pH 4 and most of heavy metals were adsorbed in pH 9. Adsorption rate of Cd decreased with decreasing pH and then adsorption rate of Cu was lower in soil.