• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.216-220
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• 2012

본 연구는 경기도 용인시에 위치한 공공하수처리장을 대상으로 소수력발전 성능특성을 예측하고 경제성을 분석하여 소수력발전소의 건설타당성을 제시하였다. 방류구에서의 수준측량 조사에 따르면 실제 유효 낙차는 4.3m로 나타났다. 최근 5년간 방류량 자료를 살펴보면 일평균 실제 처리량은 약 $30,000m^3/day$로 나타났으며, 우수 유입과 물 사용량이 증가하는 여름 및 가을에 처리량이 증가하였다. 설계유량은 유량변화에 따른 누적 확률밀도와 유량지속곡선에 근거해 산정하였으며, 시간빈도로 보았을 때 17%의 유량이 지속되는 $0.35m^3/sec$가 설계유량으로 나타났다. 예상되는 수차 발전용량은 11kW급이며, 시스템 가동율은 74%, 그리고 계통선에 송출될 수 있는 연 전력생산량은 71.3MWh로 나타났다. 경제성 평가는 신재생에너지 경제성 분석 도구인 RETScreen 프로그램을 사용하여 B/C ratio, IRR, 개발투자비 등의 경제성 평가지표들을 산정하였다. 편익(Benefit) 산정시 전력기준단가는 133.67원/kWh, 할인율 7%를 적용하였으며, 비용(Cost) 산정시 유지관리비는 초기 건설비의 1%, 사용연한 30년을 적용하였다. 경제성 분석결과 기흥레스피아의 소수력발전소 건설시 초기 건설공사비가 $165,000 일 때, B/C 1.0, NPV $3,534, 투자회수기간 15.1년으로 산정되었고 따라서 초기 건설비용이 $165,000 이하일 때 가장 경제적인 것으로 파악되었다.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.52-59
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• 2012

As the result of reviewing the linked treatment of water quality for treating process at public livestock wastewater treatment facilities for fair selection of the proper linked process in case of linking sewage treatment plant for livestock wastewater, in case of wastewater processed by bio-reactor that is only biologically-treated, the load factor showed relatively high as 1.67%(base on design quality), 2.59%(base on operation quality) regarding COD and 3.69%(base on design quality), 7.67%(base on operation quality) regarding $COD_{Mn}$ but it is judged that there is nearly no influence on the operation of sewage treatment plan. And, in case of oxidized flotation-treated water & biofiltlation-treated water that are the advanced wastewater treatment, the load factor is approximately 1% and there is concern about the installation of excessive facilities in case of installing the advanced wastewater treatment. So, in case of considering the economic efficiency & stable operation of sewage treatment plant S, it is judged to be desirable to link with wastewater processed by bio-reactor that is biologically-treated.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.130-138
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• 2020

As of 2017, the sewerage penetration rate of Seoul and metropolitan cities is more than 90%, and the number of domestic sewage treatment plants increased by 25% from 3,064 in 2010 to 4,072 in 2017. Among them, sewage treatment plant operated by SBR system is 585, which is 17% higher than 2010. In order to improve the water quality of the water source and improve the operation of the small sewage facilities, the improvement of the process was studied by applying the modelling to 49 facilities of the sewage treatment plant in Andong Imha dam area with more than 500㎥/day 3 places and 46 places less than 500㎥/day. As an improvement plan for modelling, candidate data were derived by reviewing operation data for 5 years. 49 facilities are operated by 12 types of operating processes. Among them, 1 place mort than 500㎥/day with SBR method and 9 facilities with less than 500㎥/day were selected by dividing 46 sites into 3 types. As a result of applying modelling to more than 500㎥/day, it was possible to improve the quality of discharged water through SRT control and it was found that applying model to sites of small scale treatment plants can improve the removal efficiency of TP by up to 14.4%. As a result, the data of this study could be used to improve and improve the operation of sewage treatment plants and RCSTP(Rural Community Sewage Tratment Plant).

• Journal of Korean Society of Environmental Engineers
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• v.36 no.8
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• pp.549-553
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• 2014

Variation of sewage sludge interface height and flow rate by rainfall were applied to the actual public sewage treatment plant, and the efficiency of sewage treatment was evaluated by measuring $BOD_5$, $COD_{Mn}$, SS, T-N, and T-P. When both flow and interfacial height are increased, the treatment efficiencies in terms of the five water pollutants are decreased. Among them SS is the most critical pollutant in rainfall. When 0.5 Q inflow was applied, the efficiencies were 74.2% at the sludge interface height of 0.5 m, 76.4% at 1.0 m, 70.2% at 1.5 m, and 60.7% at 2.0 m. When 1.0 Q inflow was applied, the efficiencies were 71.7% at the sludge interface height of 0.5 m, 71.9% at 1.0 m, 46.4% at 1.5 m, and -38.0% at 2.0 m. Operation at 2.0 Q~2.0 m and 3.0 Q~1.0 m above the sludge rising phenomenon occurred causing adverse effects on the public bodies. If the flow rate increases, the processing efficiency is reduced from 74.2% to 17.3%, even though the sludge interface height was maintained at 0.5 m, so that the inflow adjustment was most important during rainfall, and the interface height of 1.0 m should be maintained to minimize the adverse effect on public water system.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.470-470
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• 2011

환경부 하수재이용사업은 2007년도 하수도법 개정을 통해 공공하수처리시설 처리수의 재이용 의무화를 시작으로 2010년도 "물의 재이용 촉진 및 지원에 관한 법률"의 시행으로 전국적으로 사업이 확대되고 있다. 제주도 월정하수처리장은 2009년도 하수재이용사업지구로 선정이 되어 2010년도부터 농업용목적의 재이용으로 구체적인 설계와 시공이 추진되고 있는 사업지구이다. 제주도에서는 지하수보존을 위해 대체수자원 개발 방안을 시급히 마련중에 있다. 특히, 제주도 농업용수 종합계획수립(제주도, 2004)에는 하수처리수를 농업용수로 이용하기 위한 계획을 수립할 정도로 지하수 사용량을 줄이기 위한 노력을 진행중에 있으며, 그 일환으로 하수재이용사업을 지속적으로 추진하고 있다. 하수처리수의 농업용수 재이용은 사용된 물을 재이용함으로써 물과 에너지를 절약할 수 있고, 유역 또는 해양으로 배출되는 오염원을 억제하는 장점이 있는 반면에 농산물 생육에 직접 영향을 줄뿐만 아니라 주변의 수질 생태 토양 환경 및 영농인의 보건에도 영향을 주기 때문에 장기적인 관찰과 검증작업이 필요하다. 이 에 서울대와 한국농어촌공사는 안전한 농업용수 재이용기술을 개발하기 위해 장기간 현장시험을 통해 재이용 재배기술과 함께 보건환경에 미치는 영향을 검증하였고 그 개발기술을 월정사업지구에 적용하게 되었다. 월정하수처리장이 위치한 제주 동부의 월정지역은 농지면적이 밭(374ha)과 과수(12ha)등 제주도의 전형적인 농촌마을으로 주요 재배작물은 마늘과 당근, 쪽파, 콩 등으로서 농업기반시설의 미비로 영농에 어려움을 호소하고 있으며, 2006년도에 발생한 가뭄으로 그 해 평균 수학량의 30%가 감소된 바 있는 지역이다. 제주도 농업용수 종합계획수립(2004, 제주도)에서는 10년에 한발을 기준 으로 $43,000m^3$/일의 용수가 부족할 것으로 분석하였으며 최근 $35,000m^3$/day 규모의 상수도 확보사업 계획 수립하였으나 여전히 농업용수가 부족하다. 방류수의 수질은 방류수수질기준을 만족하지만 염분함량이 높아 직접 농업용으로 사용하기에는 적당하기 않고, 농업용재이용방류수 수질기준에 맞도록 재이용시스템을 통해 재처리하여 농업용수로 사용해야 한다. 제주도에서는 이미 제주 서부하수처리장 농업용수 재이용사업(이하 판포재이용사업)'이 완료되어 재이용수를 농업용수로 공급하고 있으며 향후 지속적으로 하수재이용사업이 확대될 것으로 판단된다.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.45-49
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• 2002

To estimate annual pollutant loading rate of n-hexane extractable material (HEM) to soil 84 sewage sludge samples were analyzed. The average content of HEM was 27.7$\pm$26.5 g/kg, and ranged from 1.05 to maximum 194 g/kg. According to the number of population of the city the areas were classified as five regions, i.e. big, large, middle, small, and rural area in which the waste water treated plants were grown. The contents of HEM were 22.7$\pm$16.7, 33.3$\pm$25.8, 22.0$\pm$8.7, 31.0$\pm$38.8, 27.7$\pm$25.1 g/kg, in big, large, middle, small, and rural area, respectively. The applicated areas with sewage sludge to land also were divided as 4 sites by US EPA criteria such as agricultural, forest, public contact sites, and reclamation site. The quantitation of annual pollutant loading rate was estimated using a function (99 percentile concentration = $\bar{X}$ + 3$\sigma$) when the application amounts were in dosages of 7,000, 26,000, 18,000, 74,000 kg/ha in 5 regions, respectively. The annual pollutant loading rate of HEM to soil by sewage sludge application was maximum 1,032, 3,832, 2,653, and 10,908 kg/ha in agricultural, forest, public contact sites, and reclamation site, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.32 no.2
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• pp.37-48
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• 2024

Wastewater treatment plants (WWTPs) are obligated to reduce carbon emissions as a part of public sector greenhouse gas (GHG) emission reduction targets. However, Sewage Statistics(2022) shows that CO₂ emissions per wastewater treatment volumes have decreased by only 3.03 % compared to 2020, which is far from enough to meet the Nationally Determined Contribution (NDC) targets. This study aimed to find operational conditions of biological reactors that minimize total carbon footprint (CFP). Total CFP considers both direct emissions from biological processes and indirect emissions from energy consumption. A study was conducted using a computer simulation program which is called as EQPS for a 4-stage BNR WWTP. The results showed that total CFP was reduced by 10.97% compared to the design condition when the mixed liquor recirculation (MLR) was set to 100 % of the influent flow. The N₂O emission factor (EF) of the target WWTP was calculated to be 0.138-0.199 %, which is significantly lower than the IPCC default value of 1.6 %. This study proposes a method to minimize total CFP in WWTPs by optimizing biological reactor operation and emphasizes the need for further research on N₂O emission reduction.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.360-366
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• 2013

This study was it conducted on effluent or river water close to discharge locations from a treatment plant, which were analyzed for the presence, phenotype and antibiotic resistance rates of Vancomycin Resistant Enterococci (VRE). The test results for isolation and identification of Enterococcus spp. showed that they all were VRE positive, with a total of 32 strains detected. Multiplex PCR was conducted for 32 strains, each of which were identified as E. faecium, and the results indicated that they were all confirmed as VRE, corresponding to the Van A phenotype. The results of E. faecium concentrations measured at various locations indicated that they were, on average, higher at the location of sewage treatment plants. The frequency of positive tests as well as the number of colonies was higher downstream of treatment plants. The minimum inhibitory concentration was inspected for 26 strains of discharged water samples from sewage water treatment plants, and 6 strains of river samples. Out of 19 antibiotics, 14 and 5 species showed resistance and sensitivity, respectively.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.386-395
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• 2015

In order to assess sewage treatment technology necessary to achieve water quality criteria in the watershed and to ensure best treatment technology is applied in building and expanding PSTWs when establishing the Watershed Sewer System Maintenance Plan, it is necessary to develop assessment guidelines to determinate the best treatment technologies applicable to the public sewage treatment works(PSTWs). Sewage treatment technologies such as anaerobic-anoxic-aerobic treatment process are employed at PSTWs, and treatment efficiency varies due to many factors such as how the PSTWs are operated. Therefore, analyzing assessment guideline of best available technology(BAT) using currently in USA and EU, this study presents assessment parameters for the assessment guidelines to be used in determining the best treatment technologies applicable to PSTWs. We have a plan to implement pilot assessment in preparation for the final assessment guidelines based on the results of professionals survey and to determine weighted factors and assessment parameters using analytic hierarchy process (AHP).

• Journal of Korean Society of Disaster and Security
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• v.12 no.2
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• pp.25-34
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• 2019

The efficiency of sewage treatment was analyzed by statistical method based on the water quality and operation data of the sewage treatment plant applying the oxidation method. The obtained water quality data were pH, temperature, BOD, SS, T-N, ${NH_4}^+-N$, and T-P of influent and discharge water. Data analysis was performed by correlation analysis, ANOVA analysis, and cluster analysis. As a result of the statistical analysis, the influent flow rate in the sewage treatment plant was the highest in summer. The average inflow flow rate was $3.000m^3/s$. According to Box plot results, COD, and T-P concentrations of effluents were not significantly different from season to season. The Pearson correlation analysis showed strong positive correlation between BOD, COD, T-N, and T-P in influent flow. Seasonal BOD and T-N concentrations were highest in winter and COD and T-P in seasonal influences. BOD showed a strong negative correlation with the water temperature, but showed a positive correlation with other operating factors such as HRT, SRT and C/N. The higher the influent temperature, the lower the BOD concentration. Therefore, retention time was shortened and BOD treatment efficiency was lowered. It was found that T-N had a higher retention time and a higher concentration than DO concentration. On the other hand, T-P did not show a significant correlation with operating factors.