• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2000년도 수정란의 위생적 처리·검사 및 특수가축의 수정란이식 기술 심포지움
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• pp.11-28
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• 2000

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2010년도 제3회 국제학회
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• pp.75-76
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• 2010

• 환경위생공학
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• 제15권3호
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• pp.50-56
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• 2000

In this study, sewage were treated with operating Two-step Aeration System and conventional activated sludge process together in a condition. At the same HRT 8hr of Two-step Aeration System and Activated Sludge Process, BOD treatment efficiency of 1st sedimentation basin effluent 36.9% by Two-step Aeration system was 12.3% higher than 24.65 by Activated Sludge Process and the COD treatment efficiency 39.8% by two-step Aeration System was 11.6.3% higher than 28.2% by Activated Sludge Process. BOD and COD treatment efficiencies of 2nd sedimentation basin effluent were 88.1% and 85.6% Two-step Aeration System and were 83.8% and 82.3% Activated Sludge Process. In the first treatment, as BOD was relatively removed a lot, F/M ratio 0.17, $0.21{\cdot}BOD/kg{\cdot}MLSS.d$ was maintained by Activated Sludge Process. Therefore it was proved that organic matter treatment efficiency by Two-step Aeration System os Higher than by Activated Sludge Process in a aeration time 8hr. $NH_4^{+}-N$ treatment efficiencies were 55.5% by Two-step Aeration System and 39.75 by Activated sludge Process. $NO_3^{-}-N$ concentration in 2nd. sedimentation basin effluent were 3.33% by Two-step Aeration System and 2.36% by Activated Sludge Process. From this result, Two-step Aeration System was proved more advantageous treatment process for nitrification than Activated Sludge Process. The fluctuation range of BOD, COD and SS concentration in 2nd sedimentation basin effluent $16~33mg/{\ell}$, $15~23mg/{\ell}$ and $14~22mg/{\ell}$ by Two-step Aeration System was smaller than $16~57mg/{\ell}$, $15~25mg/{\ell}$ by Activated sludge Process. Overall the fluctuation range in 2nd sediment basin effluent by was smaller than by Activated Sludge Process. As a result, it is possible for this Two-step Aeration with no facility investment and a little of operation condition change in a conventional sewage treatment plant to get stability and nitrification of treatment water quality.

• 환경위생공학
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• 제3권1호
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• pp.27-39
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• 1988

This investigation was carried out to evaluate the removal effect of biological contaminants for the municipal sewage treatment process at Cheonggye Cheon terminal plant which in the first plant for municipal sewage treatment in Seoul area. It was conducted in raw influent, primary treatment water and secondary treatment water from September, 1986 to July, 1987. The results were as follow; 1, The primary treatment could eliminate microbials for $65.38\%$ of total bacteria, $64.35\%$ of total coliform, $62.16\%$ of fecal coliform $69.48\%$ of pseudomonas and $64.70\%$ of fecal streptococci in averages for a year respectively. 2. The secondary treatment could eliminate microbials for $97.50\%$ of total bacteria, $97.30\%$of total coliform, $95.95\%$ of fecal coliform, $97.00\%$ of pseudomonas and $96.53\%$ of fecal streptococci in average for a year respectively. 3. In the detect rate of pathogenic agent, salmonella spp was decreased $12.5\%$ to $4.2\%$ in primary treatment and it was not detected in secondary treatment, shigella spp was detected $4.2\%$ in influent water but it was not detected in primary and secondary treatment. 4. In the seasonal variation of treatment effect, the removal of summer was the highest, and the removal of all item in winter was lower than the other seasons. 5. There was significant correlation between water temperature and microbal all items (P<0.05) $NH_3-N$ and Microbal items (P< 0.01) at raw water.

• 환경위생공학
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• 제11권1호
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• pp.45-55
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• 1996

An experimental research was conducted in order to study the combined treatment o of municipal landfill leachate and municipal sewage. The landfill leachate was that of Nanjido landfill site, and the municipal sewage was that of Chungnang municipal sewage treatment plant in Seoul. Several sets of bench~scale sequencing batch reactor(SBR) were used as e experimental apparatus. Specially investigated items in this experiment were the removal efficiency of substrate and the influence of treatment time. The experiment lasted for about 2 years. The result are as follows ; 1. The characteristics of leachate were pH 7.5~8.2, BOD 80~336mg/L, COD 908~1,460mg/L, NH3-N 1,409~2,330mg/L, T~P 2.7~7.lmg/L, Cl~3,540~4,085mg/L, a and heavy metals are a very small amount. And the characteristics of sewage were pH 6.9~7.3, BOD 78.4~129.3mg/L, COD 121.2~305.0mg/L, T~N 14.9~36.4mg/L, T-P 2.3~8.9mg/L. 2. The treatability of leachate alone was not treat well. So for the good treatment of leachate, it was necessary to deal with the pretreatment before bi이ogical treatment and a combined treatment of municipal sewage. 3. The various contents of the leachate were 5%, 10%, 30%, and 50%, and the removal efficiency of COD was 86.0%, 82.8%, 60.6%, and 31.7%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 10% of that of sewage. And the removal efficiency of COD increased n notably, as its treatment time increased. 4. The various contents of the electrolytic treated leachate were 5%, 10%, 30%, and 50%, and the removal efficiency of COD was 89.9%, 86.1%, 79.2%, and 69.8%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 30 % of that of sewage. And the removal efficiency of C COD increased notably, as its treatment time increased.

• 환경위생공학
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• 제14권4호
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• pp.137-142
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• 1999

Current semiconductor industry factories are relying on the end-of-pipe treatment technology for waste water treatment and thus they mostly suffer from severe industrial water shortage. As a result in order to solve those waste and industrial water problems, there requires to be changed to the Clean Technology, that is Pollution Prevention Technology. Through above strategic actions with the Clean Technology, we shall strength more powerful and logical environmental pollution prevention system than those in the past. By changing the end-of-pipe treatment technology for waste water treatment and thus they mostly suffer from severe industrial water problems, there requires to be changed to the Clean Technology, that is Pollution Prevention Technology. Through above strategic actions with the Clean Technology, we shall strength more powerful and logical environmental pollution prevention system than those in the past. By changing the end-of-pipe treatment technology with physical, chemical and biological treatment methods as a mixed stream basis for treating of semiconductor waste stream into clean technology with pollution prevention technology as a waste segregation basis, we can bet 20 to 30% investment reduction as compared with end-of-pipe treatment technology.The results for water quality analysis were as follows : 1. Water quality analysis of the before treatment : pH : 9~10.5, Conductivity : $300~7,000{\mu}s/cm$, TDS : more then $3,000mg/{\ell}$, COD : $200~250mg/{\ell}$, SS : $500~600mg/{\ell}$, n-H : $8.3mg/{\ell}$ 2. Water quality analysis of the after treatment : pH : 6.5~7.5, Conductivity : 0.059, TDS : $40{\mu}s/cm$, COD : $20mg/{\ell}$, SS : $5mg/{\ell}$ n-H : $0.6mg/{\ell}$

• 환경위생공학
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• 제9권1호
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• pp.17-28
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• 1994

There are many possibilities that may lead to low quality of drinking water Recently, some unknown deposits in tap water raised a lot of public concern regarding the safety of drinking water in Seoul. We analyzed the quality of tap water from several areas of Seoul, including the area where public complaints about tap water were high. The results shows that the quality of tap water in Seoul was good, well below the environmental standards. Only the tap water from the area with high public complaints showed turbidity higher than that of other area. Also, result shows that component of deposit in tap water was Al, Fe, Mn, and Zn. Based on the research result we propose several measures that might help to reduce the amount of deposit in tap water as follows : 1 Using coagulant aid when coagulating or adjusting pH when filtering. 2. Replacing old water pipeline with new corrosive- resistant one. 3. Increasing water treatment efficiency by enhancing water treatment system such as automation of water treatment system adjusting production capacity, and improving operational condition of filler basin. 4. Chlorine disinfection at the distribution reservoir would help maintaining the same pH level and chlorine concentration throughout the water pipeline and reduce corrosion of pipe.

• 환경위생공학
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• 제15권3호
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• pp.101-119
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• 2000

In order to establish water quality management planning in some watershed, water quality of the future of the watershed should be predicted first. The Yongsan river various pollutant sources ; sewage, industry, livestock, farming and so on. And pollutants from these sources are likely to increase even though a number of publicly owned treatment works(POTWs) are founded. Therefore, it is estimated that water quality if the river would be even worse than now in near future. In this study, water quality of the future(2001, 2006) on the Yongsan river was simulated with QUAL2E model. Concentration of three water quality parameters(BOD, T-N, T-P) was predicted according to dry season, low flow season, average flow season of the river with and without POTWs. The results of this study showed the significant contrast in concentration between with and without POTWs, specially in terms of T-N and T-P. Therefore, POTWs must be founded around the Yongsan river and more advanced treatment should be considered. And because these parameters are mostly affected by polluants from upper watershed, including Kwangiudcheon, water quality management planning on the Yongsan river might be focused on this area.

• 환경위생공학
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• 제19권2호
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• pp.23-29
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• 2004

An algicidal effect of endemic algicidal bacterium (Pseudomonas putida) and rotifer zooplankton (Brachionus calyciflorus) on diatom Stephanodiscus hantzschii were examined in the filtered water, and were compared with those of bacterium plus ciliate. Bacteria removed as 80% of the diatom within 3.5 days, while ciliate and zooplankton suppressed 57% and 40% of diatom during the same period, respectively. Mixed treatment of bacteria plus ciliate removed as 54% of diatoms, while that of bacteria plus zooplankton decreased as 85%. Although single bacteria and mixed treatment of bacteria plus zooplankton quickly decreased the diatom in the initial of experiment, bacteria plus ciliate perfectly removed the diatom in culture flask within 5.5 days of the study. On the other hand, other single and mixed treatments did not clear the diatom during the same period, and over 10% of them still remain in culture flask. Predator biomass in the presence of algicidal bacteria showed the growth patterns; zooplankton gradually decreased, and ciliate sustained over 0.5 cells/ml. These results indicated that the addition of ciliate to the algicidal bacterium in controlling the diatom Stephanodiscus hantzschii is more effective than that of zooplankton. Therefore, this synergistic interaction relationship between the bacterium and ciliate play an important role in the bio-manipulation using bio-agents to control the diatomal bloom in freshwater lakes and streams.

• Membrane and Water Treatment
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• 제2권3호
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• pp.175-185
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• 2011

Ultrafiltration is an emerging technology for drinking water treatment because it produces better water quality as compared with conventional treatment systems. More recently, the combination of UF technology with other processes in order to improve its performance has been observed. These associations aim to maximize the contaminants removal and reduce membrane fouling. The operational performance of contaminants removal and water production of two UF pilot plants was compared. The first plant (Guarapiranga) was fed with raw water and the second plant (ABV) with pre-treated water by the coagulation, flocculation and sedimentation processes at Alto da Boa Vista WTP (Sao Paulo, Brazil). Both units operated continuously for approximately 2,500 hours, from September/2009 to January/2010. The results showed that the ABV UF pilot plant was able to operate at higher specific fluxes (6.2 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$) than Guarapiranga (3.1 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$). However, the number of chemical cleanings conducted in both pilot units during the considered operation period was the same (4 chemical cleanings for each plant), which shows that the pre-treatment reduced the membrane fouling. The water quality at ABV for all the variables analyzed was better, but the feed water quality was also better due to pretreatment. The rejection values for the different contaminants were higher at Guarapiranga mainly because of a pollution load reduction after pre-treatment at ABV. Even with the better performance of the ABV UF pilot plant, it is necessary to take into consideration the complexity of the complete treatment system, and also the costs involved in the construction and operation of a full-scale treatment unit.