• 한국환경과학회지
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• 제14권12호
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• pp.1163-1170
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• 2005

The microbial adsorption characteristics of two different media for biological treatment were studied using attached diverse microbes onto activated carbon and ceramic. The results in the experiments of the characteristics of physical adhesion on two different media with addition of high and low concentrated substrate in the culture were observed that the efficient of adhesion onto F-400 activated carbon was higher over that of ceramic due to the surface area of media. The irradiation treatment by ultrasonication with 400 W power and 3 min retention time on the media without addition substrate conditions and subsequent mixing throughly the culture showed the highest efficiency of cell detachment on the media. Three different microbes, P. ovalis, A calcoaceticus, and B. subtillis were used for the study of the characteristics of microbial adhesion on the media. p ovalis showed the highest adhesion capability while B. subtillis showed the lowest capability adhesion onto media either addition of substrate in the culture. The mixed bacterial culture showed $10\%$ lower removal efficiency of DOC in the low concentrated substrate culture compared to the single pure culture. Whileas, it did not show significant difference between two cultures at high concentrated substrate. It was also observed same population density of microorganism by counting of microbes adhered to microbial media with an ultrasound treatment.

• Environmental Engineering Research
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• 제16권4호
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• pp.231-236
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• 2011

Biological nitrogen removal, using a continuous flow packed-bed reactor (CPBR) in a consecutive nitrification and denitrification process, was evaluated. An apparent decline in the nitrification efficiency coincided with the steady increase in $NH_4{^+}$-N load. Sustained nitrification efficiency was found to be higher at longer empty bed contact times (EBCTs). The relationship between the rate of alkalinity consumption and $NH_4{^+}$-N utilization ratio followed zero-order reaction kinetics. The heterotrophic denitrification rate at a carbon-tonitrogen (C/N) ratio of >4 was found to be >74%. This rate was higher by a factor of 8.5 or 8.9 for $NO_3{^-}$-N/volatile solids (VS)/day or $NO_3{^-}-N/m^3$ ceramic media/day, respectively, relative to the rates measured at a C/N ratio of 1.1. Autotrophic denitrification efficiencies were 80-90%. It corresponds to an average denitrification rate of 0.96 kg $NO_3{^-}-N/m^3$ ceramic media/day and a relevant average denitrification rate of 0.28 g $NO_3{^-}$-N/g VS/day, were also obtained. Results presented here also constitute the usability of an innovative porous sulfur ceramic media. This enhanced the dissolution rate of elemental sulfur via a higher contact surface area.

• 한국대기환경학회지
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• 제19권3호
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• pp.297-306
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• 2003

Works were focused on back pressure characteristics of ceramic fiber filter on DPF (Diesel Particulate Filter) system and experiments were performed to select appropriate filter which can filter particulates. Filters were installed on metal -support tube which has openings for exhaust gas flow. Ceramic fiber filters with high specific surface area and adequate high temperature strength are commercially available for filtration of diesel particulates and in -situ hot regeneration. Thus, ceramic blanket and ceramic board which are used as insulating media were applied to filter and filtration apparatus was installed on exhaust gas line connected to 2.0 L diesel engine. Alternating filter structure to adapt DPF system, collection efficiency test of diesel particulates was measured. In case of ceramic blanket, pressure drop was low, caused by the destruction of soft structures. Also, particulate collection efficiency was decreased depending on loading time. In case of ceramic board, structure design was altered to reduce back pressure on DPF system. Structure design was altered to induce Z-flow by making 10 mm and 5 mm holes on the surface of media. Alteration of 5 mm hole showed that media have low back pressure but particulate collection efficiency was 77%, while 10 mm hole showed that of 90%.

• 상하수도학회지
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• 제14권1호
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• pp.37-44
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• 2000

Laboratory experiments were conducted to investigate the performances of anaerobic filters packed with ceramic tube and pall-ring media treating a dairy waste. The media packing volume was 65% of effective volume of anaerobic filter. Organics removals of anaerobic filters were maintained above 80% even at an organics loading rate of $10kgCOD/m^3/d$, and this was comparable to aerobic treatment of organic wastes. Organics removals of the ceramic tube anaerobic filters were always lower than those of the pall-ring anaerobic filters due to intrinsic physical property of ceramic tube, especially lower void space which caused to clogging and entrapment of biogas, substrate transfer limitation, and irregular evolution of biogas leading to loss of solids and biomass. This was clearly observed in higher concentration of TSS in the effluent from the ceramic tube anaerobic filter despite of higher retention capacity of TSS compared with pall-ring media. Vertical distribution of organics and solids in the filters showed above 90% of organics and solids in influent were removed below 20% of reactor height, and 50% of remaining organics and solids were removed though media packing zone. Effluent quality from the anaerobic filter was heavily depended on media itself as well as suspended biomass formed below media. It is therefore concluded that the type of media played an important role in biomass accumulation arid gas-liquid-solid separation efficiency. Type of media did not affect the start-up behaviors of the anaerobic filter, and supernatant from anaerobic digested sludge showed a good performance as a seeding materials.

• 상하수도학회지
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• 제20권6호
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• pp.837-848
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• 2006

This paper presents the test results of biological aerated filtration(BAF) process to replace activated sludge process by enhancing treated effluent quality and reducing the costs. In BAF process both BOD and SS compounds in wastewater are degraded and removed by biological reaction and filtration. Upflow BAF with expanded polypropylene media and downflow BAF with ceramic media were used to investigate the effects of hydraulic and organic loads on effluent quality. As a result, in BAF processes which has different media, upflow BAF reactor shows 5% higher efficiency than downflow BAF and this phenomena caused by backwashing methods and operational conditions. The results of influence factors analyzed by Factor Analysis Method in BOD and SS treatment efficiency are the size of media, hight of media bed and type of media. The quantitative effects of media size are 5.73% in TBOD, 5.78% in SBOD and 7.65% in TSS, so we confirmed the main factor is media size.

• 한국산학기술학회논문지
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• 제13권10호
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• pp.4910-4916
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• 2012

세라믹담체에 적용한 4종의 해양박테리아 (Aeromonas hydrophila, Chryseomonas indologenes, Pseudomonas diminuta, Vibrio parahaemolyticus)의 저농도 질소 인 제거 효율의 변화를 분석하였다. 해양박테리아는 광양만에서 분리 동정하였다. 담체에 적용한 4종의 해양박테리아 모두 대조군에 보다 약 3배 정도의 성장률이 증가하였으며, 암모니아서 질소 제거효율도 30% 이상 증가하였다. 질산성 질소의 제거 효율은 A. hydrophila 균주가 가장 높았으며, 인의 제거는 P. diminuta 균주가 가장 높은 것으로 나타났다. 본 연구의 결과는 세라믹담체는 질소-인 제거 효율 증진에 좋은 재료이며, 분리된 해양박테리아는 현장의 저농도 질소-인 조절에 유용할 수 있음을 보여준다.

• 한국광물학회지
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• 제31권4호
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• pp.227-234
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• 2018

본 연구는 세라믹 압출법을 이용하여 납석기반 세라믹 반응매질을 제조하였다. 납석의 광물학적 특성은 XRD, XRF, DSC-TGA 및 제타전위분석을 실시하였으며, 납석기반의 세라믹 반응매질은 다양한 소성온도범위($500{\sim}1,300^{\circ}C$)에서 수행하였다. 소성온도가 증가할수록 반응매질의 강도는 증가하였으나, 비표면적은 감소된다. 온도변화에 따른 납석의 무게손실과 구조변화를 XRD, DSC-TGA 및 SEM 분석을 통해 확인하였으며, 엽납석은 소성온도 $1,000^{\circ}C$에서 pyrophyllite dehydroxylate로 전이되며, $1,300^{\circ}C$에서 뮬라이트와 크리스토발라이트로 상변화가 발생된다. 본 연구를 통해 납석은 투수성반응벽체 적용을 위한 반응매질로서 세라믹 지지체 역할을 수행할 수 있을 것으로 판단된다.

• 한국세라믹학회지
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• 제28권10호
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• pp.838-842
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• 1991

• 한국세라믹학회지
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• 제53권6호
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• pp.641-646
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• 2016

The effects of water addition on $Y_2O_3$ coatings or thick films prepared by plasma suspension spray (SPS) have been investigated. Water addition in suspension media was found to be effective to control the color of a $Y_2O_3$ coating prepared by SPS. The color changed with water addition at the shortest stand-off distance of 50 mm even if samples had the same crystalline phase. Change was not correlated with fragmentation behavior of liquid suspension inside the plasma jet. Water content over 50 vol% was found to produce unmelted particles, indicating that water suppressed heat transfer to the particles. However, plasma jet temperature was not affected. Instead, the coating fabricated with water addition has higher oxygen and lower carbon content compared to these characteristics of the coating without water addition. This was attributed to the retarded complete evaporation of liquid media from the suspension droplet, resulting in inhibition of excessive heating and evaporation of the molten $Y_2O_3$ droplet. In this regard, crystalline phase development with respect to stand-off distance and water addition was discussed.

• 한국세라믹학회지
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• 제44권12호
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• pp.747-750
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• 2007

The thermal conductivities of nano-sized fumed silica-based insulation media were investigated by varying a mean particle size of the silicon carbide opacifiers and ceramic fiber content. Opacifying effect of ceramic fiber and silicon carbide powders was discussed in terms of their content and the mean particle size of them. As the fiber contents increased from 10 wt% to 30 wt% in a material, its thermal conductivity at temperatures of about $620^{\circ}C$ decreased from 0.171 $Wm^{-1}K^{-1}$ to 0.121 $Wm^{-1}K^{-1}$. Meanwhile, the thermal conductivity at temperatures of about $625^{\circ}C$ decreased from 0.128 $Wm^{-1}K^{-1}$ to 0.092 $Wm^{-l}K^{-1}$ as the mean SiC particle size decreased from $31{\mu}m$ to $10{\mu}m$.