• Membrane Journal
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• v.22 no.2
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• pp.95-103
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• 2012

To treat nitrate and non-biodegradable organics effectively in sewage, industrial wastewater and livestock wastewater, the activated sludge process integrated by a membrane separation and a porous electrode- electrolysis was proposed and its efficiency was investigated. The proposed system was consisted of 3 processes; activated sludge, membrane filtration and electrolysis. In the study, the membrane filtration played a role in reducing the load of the electrolysis to operate the proposed process stably. The electrolysis consisted of a porous electrode to increase the efficiency due to the extension of the specific surface area. Additionally, redox reaction in the electrolysis was induced by decomposing influent water as current was applied. As a result, hydrogen free radicals and oxygen radicals as intermediates were produced and they acted as oxidants to play a role in decomposing non-degradable organics. It was environmentally-friendly process because intermediates produced by porous electrode were used to treat waste matters without supplying external reagent. Experimental data showed that the proposed process was more excellent than activated sludge process. SS removal efficiencies of the proposed process, membrane filtration and activated sludge process were about 100%, about 100% and about 90%, respectively. COD removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 92%, about 84% and about 78%, respectively. T-N removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 88%, about 67%, and about 58%, respectively. The SS data showed that SS was efficiently removed in the single of the membrane filtration. The COD/T-N data showed that COD/T-N of membrane hybrid process was treated by removing a little soluble organics and SS, and that COD/T-N of electrolysis hybrid process was treated by oxidize organics with high removal rate.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1013-1019
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• 2007

Electronic wastes have increased tremendously. However, any reliable treatment methodologies have rarely been established. Electronic wastes have posed serious disposal problem due to their physico-chemical stability. This paper investigated the application possibility of pyrolysis for the purpose of recycling the p-CCL(phenol based Copper Clad Laminate). Thermogravimetric analysis(TGA) was used to investigate the thermal decomposition pattern of p-CCL. We elucidated the characteristics of pyrolysis by-products at operating temperatures of 280, 350 and $600^{\circ}C$. GC/MS and FT-IR were used to characterize the liquid by-products along with general characterization methods such as Ultimate Analysis, Proximate Analysis and Heating Value, whereas general characterization methods were only introduced for the solid by-products. At a heating rate of $5^{\circ}C$/min, TGA curves exhibited three decomposition stages: (1) low-temperature decomposition region$(<280^{\circ}C)$, (2) medium temperature region$(280\sim350^{\circ}C)$ and (3) high-temperature region$(>350^{\circ}C)$. The major compounds of liquid by-products at low- and medium-temperatures were accounted for by water and phenol, whereas branched phenols and furans were major compounds at high-temperatures. As the temperature increases, volatile quantities decreased but the fixed carbon increased. High heating values of solid by-products($7,400\sim7,600$ kcal/kg) would suggest that the solid by-products could be applicable as fuel. In addition, high fixed carbon but low ash content of the solid by-products offered an implication that they are capable of being upgradable for adsorbent after applying appropriate activating process.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.859-870
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• 2004

This study was conducted to investigate physico-chemical changes of pork prepared by Korean traditional 3 types seasoning such as soybean sauce(Tl); garlic sauce(T2); red pepper sauce(T3). The seasoned samples were aged at 0 ${\pm}$ $1^{\circ}C$ for 30 days. The results obtained were as follows; Salinity(%) and saccharinity(%) of sauce were significantly decreased(P<0.05) among the all treatments during aging periods, whereas fermented meats were significantly increased(P<0.05). pH of sauce and fermented meat were tended to increased as aging period. Water-Holding Capacity(WHC) and shear force of fermented meat increased(P<0.05) among the all treatments at 20 days of storage, and decreased after that period. In color, $L^* and b^* value of T3 were lower, while a^*$ value was higher than other treatments during aging period. Volatile Basic Nitrogen(YBN) value of all treatments were increased(P<0.05) after 20 days of storage. YBN value of T3 was significantly higher(P<0.05) compared with other treatments. Thiobarbituric Acid Reactive Substances(TBARS) was rapidly increased until 10 days of storage and somewhat decreased up to 20 days after 10 days in all treatments, it was re-increased after 20th days. T3 showed the highest TBARS among the all treatment groups. Total bacterial and Lactobacilli spp. were significantly increased(P<0.05) in all treatments at 10 days of storage and decreased after that period, however it tended to increased at 30 days of storage. In sensory evaluation, overall acceptability in all treatments were increased after 20 days of storage compared to initial storage and it score was similar thereafter.