• 상하수도학회지
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• 제29권3호
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• pp.359-370
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• 2015

This study developed an up-flow wetland providing either an eco-friendly follow-up process of medium-sized public treatment facility for livestock manure or a non-point source pollution controller near livestock farms. The four bench-scale up-flow wetlands were operated with four different bed media sets. The removal efficiencies of the wetland effluent for CODCr, TN, TP, SS were 35.2 %, 29.5 %, 31.2 % and 52.2 % for set 1(Blank, without reed, with bio-ceramic), 40.6 %, 43.4 %, 42.2 % and 55.4 % for set 2(with bio-reed & without bio-ceramic), 45.2 %, 48.7 %, 46.6 % and 66.3 % for set 3(with bio-reed & bio-ceramic), 32.9 %, 27.3 %, 29.3 % and 54.1 % for Set 4(with reed & bio ceramic), respectively. The set 3 condition having a mixture of bio-reed and bio-ceramic showed the highest efficiency in the bench-scale evaluation. This study suggests a mixture of bio-reed and bio-ceramic as suitable bed media in the construction of artificial wetlands near livestock farms. Soils including the bed media were monitored during the evaluation for trace elements. Soil analysis results were satisfied with the Korean Soil Contamination Standard. This study showed that the up-flow constructed wetland was feasible to treat the effluent livestock wastewater treatment facility.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.733-737
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• 1996

The formation of microbial films(biofilm) by a non-sulfur phototrophic bacteria, Rhodopseudomonas capsulata, on inorganic media was studied. Porous ceramic beads(PCB) were superior to other immobilizing media for the biofilm formation in a packed-bed reactor. It was found that the formation of microbial films favored a lower hydraulic retention time, showing a higher ratio of cells attatched to the media to those suspended in the solution. The cell concentration in the biofilm reactor was as high as 11,400mg/l, which is 8-folds of the cell concentration in an ordinary suspended treatment. It was observed that the formation of micribial film by R. capsulata followed a general serial process of cell attachment, microcolony formation, and biofilm formation. The microbial films thus formed was very stable even for an extremely high volumetric BOD loading rate of 15gBOD/l day. The scanning electron micrographs of the microbial films showed that the cells were attached to both the surface and pores of the media.

• 상하수도학회지
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• 제26권6호
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• pp.797-805
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• 2012

Contribution of immobilized media with bacteria to the odor removal was evaluated in a lab scale bio-filter compared to that with sponge or ceramic media without the immobilized bacteria. Candida tropicalis for volatile organic compounds and ammonium oxidizing bacteria (AOB) for inorganic compounds were used as seeds in lab-scale bio-reactors. Three different type of media in the bio-reactors that immobilized bioreactor (IBR), sponge bioreactor (SBR), and ceramic bioreactor (CBR) were examined, respectively. An empty bed contact time (EBCT) of the bio-filters was fixed as 60 seconds, and the inlet concentration of toluene was changed from 20 ppm to 200 ppm to observe the removal efficiency depending on the concentrations. As a result, the maximum elimination capacities of IBR, SBR, and CBR were 166 $g/m^3/hr$, 138 $g/m^3/hr$, and 138 $g/m^3/hr$, respectively. In addition, toluene as an organic compound and ammonia as an inorganic compound were applied together with different inlet concentrations varied from 80 ppm to 250 ppm of toluene and from 2.5 ppm to 40 ppm of ammonia. The toluene maximum elimination capacities in IBR, SBR, and CBR were 97.4 $g/m^3/hr$, 59.5 $g/m^3/hr$, and 81.9 $g/m^3/hr$, respectively. The ammonia maximum elimination capacities were reached as 7.2 $g/m^3/hr$ in IBR, 6.6 $g/m^3/hr$ in SBR, and 7.0 $g/m^3/hr$ in CBR.

• 한국세라믹학회지
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• 제33권2호
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• pp.214-222
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• 1996

The effect of physicochemical properties of organic solvent and dispersant among organic solvent dispersant binder and plasticizer which are used as processing additives in MLCC fabrication process on the dispersion of BaTiO3 was studied. The steric and electrostatic stabilization mechanisms in dispersion of BaTiO3 in organic media were evaluated respectively. The sttability of BaTiO3 achieved bysteric stabilization was dependent on the fraction of surface coverage of dispersant adsorption on BaTiO3. The electrostatic repulsive forces of BaTiO3 particles dispersed in orgainc media was found to be appreciabley great and dependent mainly on the kinds of organic solvent used. The mechanism affecting the stability of BaTiO3 was studied by the method of rheologi-cal behaviors of BaTiO3 suspension.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.129.1-129
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• 2003

• 한국세라믹학회지
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• 제30권1호
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• pp.78-84
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• 1993

In PMN-pyrochlore phase mixtures, dielectric constant was measured as a function of the volume fraction of pyrochlore phase and considered with general effective media(GEM) equation. For the application of GEM equation to this system, the critical volume fraction(Vc) where connectivity between the perovskite PMN and pyrochlore phase changed from 0-3 to 3-3, was determined based on the each particle size ratio of two phases with microstructural observation. And then the t value was determined from modified percolation powder-law dependence ( K-Kc (V-Vc)t). In the case of applying such values of t and Vc to the GEM equation, which provided a reasonable fit to the measured dielectric constant within the experimental error range.

• 한국환경과학회지
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• 제14권9호
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• pp.843-849
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• 2005

The objective of this research was to investigate the removal efficiencies ofVOCs and odors with newly developed biofilter which was designed to sustain the biofilm constantly on the packed media. Initially, four types of media, for example, fiber, activated carbon, ceramic and the mixture of activated carbon and ceramic(AIC mixture J, were used for packed materials of biofilter. When ethylalcohol was selected as a test gas for media efficiency, fiber and AIC mixture had better removal efficiencies of ethyl alcohol than others. Removal efficiencies for acetaldehyde, ethyl alcohol, butylalcohol, ethylacetate and diethylamine in biofilter with fiber and AIC mixture as packed media were increased as the residence time increased. Butylalcohol, especially, showed the maximum removal efficiency among all used VOCs and odors. In case of ethyl acetate, the difference of removal efficiencies between low and high residence times was wide remarkably.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2007년도 제34회 시멘트 심포지엄
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• pp.150-159
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• 2007

• 한국약용작물학회지
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• 제12권2호
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• pp.118-122
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• 2004

We have investigated that a couple of soft ferrite ceramic powders having a spinal structure have shown the effect on growth and secondary metabolites production of some medicinal plants cultured in vitro. The addition of the ceramic powders as bare state to culture medium has stimulated the growth of Achyranthes japonica callus and plantlet, adventitious root of Hyoscyamus niger and Platycodon grandiflorum hairy root about 65, 75, 150 and 50%, respectively. Whereas Centella asiatica callus and plantlet, Scopolia parviflora hairy root, and Hyoscyamus albus adventitious root were not affected markedly. Moreover, the ceramic powder has enhanced the growth of H. niger adventitious roots even under conditions of irradiating alone without any direct contact between ceramic powder and media. Based on growth stimulation effect, the ceramic powders have enhanced the gross production of tropane alkaloid in H. niger adventitious root, and polyacetylene in P. grandiflorum hairy root about 35 and 30%, respectively.

• 한국연소학회지
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• 제2권1호
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• pp.1-8
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• 1997

Premixed combustion within porous ceramic media is numerically studied to understand burning characteristics and to find best configurations for burner implementations. Among many parameters, critical to burner performance, flame location and extinction coefficient are selected as major parameters for this study. The flame structure and burner performance with respect to these two parameters are observed. In the study, it is found that the location of flame is the most important in porous burner operation since it affects the rate of heat transfer and flame structure. Stability of the flame within the porous ceramic burner is discussed with respect to the flame location. It is found that to obtain high radiative output, the flame should be located downstream section of the burner. But the flame is to be unstable at most of downstream section except near the exit plane. To overcome this problem, new porous ceramic burner, using different ceramic properties in one burner instead of single property ceramic, is made and tested. With a combination of ceramics of high extinction coefficient at upstream and another material of low extinction coefficient at downstream of the burner, the flame can be stabilized at wider region of the burner with higher radiative output compared to the original burner configuration.