• Environmental Engineering Research
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• 제22권2호
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• pp.210-215
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• 2017

Produced water is the largest wastestream of oil and gas exploration. It consists of various organic and inorganic compounds that hinder its beneficial use. This study compared the treatment of produced water in a batch suspended and biofilm activated sludge process. The biofilm carrier material was made from Gardenia Carinata shell. COD, $NH_4{^+}-N$ and $NO_3-N$ removal was monitored in both the suspended (control) and floating carrier bioreactors. The results show a rapid reduction of produced water constituents in the floating carrier bioreactor. COD, $NH_4{^+}-N$ and $NO_3-N$ removal was in the range of 99%, 98% and 97% for the floating carrier bioreactor whereas it was 88%, 84% and 83% for the control bioreactor. The rapid reduction of COD, $NH_4{^+}-N$ and $NO_3-N$ clearly indicate that the floating carrier materials served as an attached growth medium for microorganisms, improved the breakdown of produced water constituents and reduced inhibition of microbial metabolic activities.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.21-22
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• 2005

Partially-depleted Silicon on insulator metal-oxide-semiconductor field- effect transistors (PD-SOI MOSFETs) with Silicon-germanium (SiGe) layer is investigated. This structure uses SiGe layer to reduce the kink effect in the floating body region near the bottom channel/buried oxide interface. Among many design parameters influencing the performance of the device, Ge composition is presented most predominant effects, simulation results show that kink effect is reduced with increase the Ge composition. Because the bandgap of SiGe layer is reduced at higher Ge composition, the hole current between body and SiGe layer is enhanced.

• Journal of Advanced Marine Engineering and Technology
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• 제37권8호
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• pp.843-848
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• 2013

LNG 수요의 증가에 따라, LNG FPSO (부유식 생산저장 하역설비) 선박 및 LNG 선박의 건조도 지속적으로 증가하고 있고, 다양한 형태의 저장탱크 설계가 시도되고 있다. 본 논문에서는 LNG를 저장하는 선박 화물창 내부탱크의 방식으로 5~9% Ni강재를 적용하고, 단열재를 우레탄폼 블록 대신에 펄라이트 분말을 충전하는 새로운 선박 탱크 형식을 제안하였다. 펄라이트 단열재의 적용 가능성을 위하여 필수적으로 검토되어야 하는 펄라이트의 내부탱크 벽체에 가하는 압력, 압력 흡수를 위하여 적용되는 탄성 블랭킷의 특성, 블랭킷의 적정 설계두께, 내부탱크 설계압력 등 설계 인자들을 분석하였다. 연구결과로, 블랭킷의 두께설계 기준은 내부탱크 단열간격의 1/4~1/3 사이가 되어야 하고 적정 두께는 30% 정도가 되었으며, 탱크 설계압력 기준은 블랭킷 두께에 따라 1,500 Pa 이하가 되어야 하는 것으로 얻어졌다.