• Journal of Korean Society of Water and Wastewater
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• v.11 no.1
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• pp.99-108
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• 1997

This study examined the feasbility of upgrading D waste water treatment plant which treats incoming wastewater by primary sedimentation only. By adding 20-40 ppm of Hi-PAX into the outlet of the aerated grit chamber, BOD and SS removal efficiences were improved from 29% and 36% to 53 % and 73%,respectively. However, chemically enhanced primary treatment failed to meet the upcoming wastewater quality standard(BOD and SS <20 mg/l) consistently. This was suspected to result from the deteriorated plant return stream. The wastewater treatment by chemical treatment should have increased the amount of the sludge to be removed as the sludge production was increased. Chemically enhanced primary treatment is anticipated to consistently produce effluent of the 1996 standards quality by adjusting the amount of the sludge to be removed. Besides BOD and SS removal, chemically enhanced primary treatment resulted in the improved T-P removal from 30% to 64-74%. However, such benefit was not observed in T-N removal. Improved T-P removal will be expected to help control water pollution in Masan bay.

• Journal of Environmental Health Sciences
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• v.19 no.3
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• pp.1-16
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• 1993

This paper describes an investigation to determine whether the activated sludge (AS) process could be used for the treatment of wastewater at the Union Carbide Coporation (UCC) plant in Seadrift, Texas. This plant presently utilizes a waste stabilization pond (WSP) system for treatment of the wastewater. The treatment system consists of an in-plant primary WSP and two off-plant WSPs (secondary and tertiary WSPs), run in series. The total hydraulic detention time of the WSP system is approximately 150 days. Several laboratory-based treatability studies have been conducted to evaluate the performace of the WSP system and the degradability of specific chemical compounds. From an additional study, it was determined that the WSP system was stressed and occasionally operating near the limit of its treatment capacity. The existing primary WSP plays an important role in the overall treatmemt system, because it not only functions as a pH and organic-strength equalization basin, but also serves as a "preconditioning" basin by fermenting high strength organic wastes to volatile organic acids for subsequent degradation in the escondary WSP. However, in view of pending RCRA legislatin conerning the "proposed organic toxicity characteristics limits" (40 CFR Part261: Federal Register, July, 1988), it is possible that the primary WSP will have to be abandoned in favor of alternative treatment options. Therefore the main purpose of this study was to perform activated sludge treatability evaluations for the development of an alternative to the existing primary WSP treatment ststem. In addition, another purpose was to determine the degradability of bis(2-chloroethyl)ether (Chlorex or CX) and benzene(BZ) in the activated sludge process. The presence of these two chemicals in the wastewater of the plant prompted the question of whatedether they could be degraded in an activated sludge system.

• Journal of Korea Water Resources Association
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• v.52 no.11
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• pp.947-950
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• 2019

The main feature of this paper is to provide a driving control strategy to improve the primary clarifier treatment efficiency in the initial rainfall inflow. With the recent development of IoT technology and sensing technology, the basis for operation control of wastewater treatment facilities has been improved. As a result of improving the efficiency of treatment of primary clarifier using on-line measurement results, it is possible to minimize the outflow of untreated sewage and contribute to the improvement of operation efficiency of wastewater treatment plants.

• Journal of environmental and Sanitary engineering
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• v.3 no.1 s.4
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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.

• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.55-68
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• 2020

Because of the intensified environmental problems such as climate change and resource depletion, sewage treatment technology focused on energy management has recently attracted attention. The conversion of primary sludge from the primary sedimentation tank and excessive sludge from the secondary sedimentation tank into biogas is the key to energy-positive sewage treatment. In particular, the primary sedimentation tanks recover enriched biodegradable organic matter and anaerobic digestion process produces methane from the organic wastes for energy production. Such technologies for minimizing oxygen demand are leading the innovation regarding sewage treatment plants. However, sewage treatment facilities in Korea lack core technology and operational know-how. Actually, the energy potential of sewage is higher than sewage treatment energy consumption in the sewage treatment, but current processes are not adequately efficient in energy recovery. To improve this, it is possible to apply chemically enhanced primary treatment (CEPT), high-rate activated sludge (HRAS), and anaerobic membrane bioreactor (AnMBR) to the primary sedimentation tank. To maximize the methane production of sewage treatment plants, organic wastes such as food waste and livestock manure can be digested. Additionally, mechanical pretreatment, thermal hydrolysis, and chemical pretreatment would enhance the methane conversion of organic waste. Power generation systems based on internal combustion engines are susceptible to heat source losses, requiring breakthrough energy conversion systems such as fuel cells. To realize the energy positive sewage treatment plant, primary organic matter recovery from sewage, biogas pretreatment, and co-digestion should be optimized in the energy management system based on the knowledge-based operation.

• Journal of Environmental Impact Assessment
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• v.14 no.5
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• pp.263-273
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• 2005

In this study, the major emission procedures and emission characteristics were identified at the site of sewage treatment plant which is one of the major sources of ammonia. At the same time the emission factors and emission rates were estimated. In order to calculate the emission flux, we used a Dynamic Flux Chamber(DFC), which is found to be a proper sampling devise for area sources such as sewage treatment plant. It was found that the most stable sampling condition was when the stirrer's speed of DFC was 120RPM, and it would be the best time to take a sample 60 minutes later after setting the chamber. The relatively higher flux was shown in Autumn compared to summer and winter. Annual ammonia emission rates procedures were calculated as $906.32{\mu}g/activity-ton$, $1,114.72{\mu}g/activity-ton$ and $437.53{\mu}g/activity-ton$ each at the primary settling basin, aeration basin and the final settling basin, respectively. The ammonia emission rate the highest at in the aeration basin according to this test. This results was due to that the surface of aeration basin or the final settling basin is relatively wider than the primary settling basin.

• Journal of Environmental Health Sciences
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• v.7 no.1
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• pp.1-7
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• 1981

During 20 days from November 4 to 28, 1980, the quantities of grease and oil, BOD (biological oxygen demand), COD (chemical oxygen demand), SS (suspended solid) were measured at Grit Chamber, Primary Sedimentation Tank, Secondary Sedimentation Tank in Chung Gye Chun sewage treatment plant. The results were as follows. 1. The average of grease and oil quantities were 251mg/l at Grit Chamber, 185mg/l at Primary Sedimentation Tank, 47mg/l at Secondary Sedimentation Tank. 2. In the secondary treatment for the removal of grease and oil, the removed quantities of grease and oil were increased according to increasing the quantities of influent grease and oil. The regression equation were as follows G.O.removed=0.731 G.O. influent+3.235 (r=0.887) 3. The average of grease and oil removal rate was 76.4% and the standard deviation of grease and oil removal rate daily was 10.6%. 4. G.O. (grease and oil) and BOD, COD, SS showed significant correlationship at Grit Chamber, Primary Sedimentation Tank, Secondary Sedimentation Tank. (P<0.05). 5. In the secondary treatment, effluent grease & oil and other parameters were analyzed by means of Stepwise multiple regression. Multple regression equation for estimates of effluent grease and oil were as follows. $GO_E=-9.1637+2.0380 SS_E+0.068 SS_I$ (r=0.778) 6. The correlative parameters for the effluent grease and oil seem to be the influent SS and the effluent SS. 7. It was estimated that the removal of grease and oil would be improved by means of improvement of suspended solids removal efficiency but it is necessary to inquire further into the study.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.494-497
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• 2012

A methodology to predict the output performance of small hydro power using treated effluent in wastewater treatment plant has been studied. Existing plant located Kyunggi-Do were selected and the output performance characteristics for these plants were analyzed. As a result, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power in wastewater treatment plant. Additionally, primary design specifications such as design flowrate, capacity, operational rate and annual electricity production were estimated and discussed.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_1
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• pp.35-40
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• 2001

Effect of the addition of an enzyme/microbial additive(EMA) to enhance anaerobic digestion of the primary sludge was investigated. Two laboratory scale anaerobic digester were operated with primary sludge taken from a municipal wastewater treatment plant. The digester receiving EMA with the sludge feed performed better than the control digester, when both were operated at 10-days and 15-days Solid Retention Time(SRT). Addition of EMA to the experimental digester provided 7%(10-days SRT) and 16%(15-days SRT) higher gas production compared to the control digester when both were fed with the same amount of volatile solids. The reduction in volatile solids was 24% better in the experimental digester compared to the control ar 10-days SRT, and the improvement 10% at 15-day SRT. Improvement in COD reduction, and fecal coliform density reduction were also seen in the experimental digester due to EMA addition compared to the control both ar 10-days SRT and 15-day SRT operation. Preliminary cost benefit analysis for a wastewater treatment plant showed that approximately $115/day in gas production improvements can be realized upon addition of EMA to primary sludge anaerobic digesters operating at 10-day SRT. The value of increased gas production was $172/day if the same digesters are operated with EMA addition at 15-day SRT.

• Journal of the Korean Solar Energy Society
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• v.33 no.2
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• pp.78-83
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• 2013

A methodology to predict the output performance of small hydro power plant using treated effluent in waste water treatment plant has been studied. Existing waste water treatment plant located in Kyunggi-Do were selected and the output performance characteristics for these plants were analyzed. .Based on the models developed in this study, the hydrologic performance characteristics for SHP sites have been analyzed. The results show that the flow duration characteristics of small hydropower plant for waste water treatment plant have quite differences compared with small hydropower plant for the river. As a result, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power in waste water treatment plant. Additionally, primary design specifications such as design flowrate, capacity, operational rate and annual electricity production were estimated and discussed. It was found that the models developed in this study can be used to decide the design performance of small hydropower plant for waste water treatment plant effectively.