응집에 의한 탁도물질 및 용존 유기물질의 동시제거에 대한 연구

전항배,김학성,정상기 대한상하수도학회 1995 상하수도학회지 Vol.9 No.3

Various humic substances are widely distributed in natural water body, such as rivers and lakes and cause the yellowish or brownish color to water. The evidence that humic substances are precursors of THMs formation in chlorinated drinking water has been reported in the literatures. For the reason of public health as well as aesthetics, needs for humic substances removal have been increased in the conventional water treatment process. In this research, the characteristicx of aluminium colgulation of humic acids and humic acids were investigated. The optimum pH and coagulants dosage to remove these materials simultaneously by coagulation were also studied. The results are as followed; 1. UV-254 absorptiometry for measuring the concentration of aquatic humic acids showed good applicability and stable results. 2. The optimal pH range for humic acids removal by aluminium coagulation was 5 to 5.5, however, an increase in aluminium coagulant dosage could enhance the removal rate of humic acids in the wide pH range. 3. Coprecipitation of humic acids in the typical pH range of 6.5 to 8 in water treatment processes may require the sweep coagulation mechanism with the excess aluminium coagulant dosage. 4. Using PAC(poly aluminium chloride) or PASS(poly aluminium silico sulfate) as coagulants was able to expand the operating range for removing humic acids. 5. From the coagulation of humic substances(UV-254) and turbidity at pH range of 5.5-6.0 and alum dose of 86 ppm, the removal efficiency of turbidity from the reservoir water was above 90% and that of UV-254 was above 70%. 6. By using the reservoir water, the optimum condition of rapid mixing for simultaneous removal of turbidity and UV-254 absorbance was pH of 5.8 and LAS dose of 86 ppm, in this study.

공공하수도 관리대행 성과평가 지표별 가중치분석을 통한 우선순위에 대한 연구

위미경,박철휘 대한상하수도학회 2020 상하수도학회지 Vol.34 No.6

The 37 indicators for performance evaluation of public sewage management agencies are divided into four major categories (agency manpower management ability, wastewater treatment plant operation and management, sludge and water reuse, service quality) in the first stage, and the necessity and score acquisition for the detailed indicators by each major category in the second stages. Priority was investigated through the Analytic Hierarchy Process(AHP) analysis technique for ease and relevance of company efforts. Also, based on the results of this analysis, integrated type weighting and relative importance were analyzed. As a result of the analysis, the weight and relative importance of the first stage classification were in the order of wastewater treatment plant operation and maintenance, operation agency manpower management ability, sludge and water reuse, and service quality. As a result of analyzing the weights and priorities of the detailed performance indicators in the second stage, it was found that operator's career years, the percentage of certification holding rate in operators, compliance with the effluent water quality standards, training times for operators, and efforts to manage hazardous chemicals were important. Some of the indicators of operation agency performance evaluation may include indicators in which the performance of the company's efforts is underestimated or overestimated. In order to improve this, it is necessary to give weights in consideration of the necessity of the indicator, the relevance of the company's efforts, and the ease of obtaining scores.

하수관거보수 순위결정을 위한 침입수/유입수량에 대한 정량/정성 분석의 실행 연구

박명균,김대성,안원식,오정미 대한상하수도학회 2006 상하수도학회지 Vol.20 No.1

파일럿 플랜트 규모에서 일체형 침전부상공정 (SeDAF)의 설계인자 및 운전특성에 대한 실증적 평가

장여주,김원재,정진홍,임현만 대한상하수도학회 2021 상하수도학회지 Vol.35 No.1

Eutrophication and algal blooms can lead to increase of taste and odor compounds and health problems by cyanobacterial toxins. To cope with these eco-social issues, Ministry of Environment in Korea has been reinforcing the effluent standards of wastewater treatment facilities. As a result, various advanced phosphorus removal processes have been adopted in each wastewater treatment plant nation-widely. However, a lot of existing advanced wastewater treatment processes have been facing the problems of expensive cost in operation and excessive sludge production caused by high dosage of coagulant. In this study, the sedimentation and dissolved air flotation (SeDAF) process integrated with sedimentation and flotation has been developed for enhanced phosphorus removal in wastewater treatment facilities. Design and operating parameters of the SeDAF process with the capacity of 100 m3/d were determined, and a demonstration plant has been installed and operated at I wastewater treatment facility (located in Gyeonggi-do) for the verification of field applicability. Several empirical evaluations for the SeDAF process were performed at demonstration-plant scale, and the results showed clearly that T-P and turbidity values of treated water were to satisfy the highest effluent standards below 0.2 mg/L and 2.0 NTU stably for all of operation cases.

보고 : 하수도 처리용 염소계통 (鹽素系統)의 소독제에 대한 고찰

이기영 대한상하수도학회 1988 상하수도학회지 Vol.1 No.1

하수처리시스템 온실가스 저감활동에 대한 CDM 사업 적용에 관한 연구

곽인호,황용우,조현정,박광호 대한상하수도학회 2010 상하수도학회지 Vol.24 No.3

In general, wastewater treatment systems consume high-energy consumption depending on operation characteristics of the facilities. Therefore, greenhouse gas(GHG) reduction activities that are application of digestion gas, induction of renewable energy etc. are conducted to reduce energy consumption and to increase energy independence ratio. In this study, GHG reduction in wastewater treatment system identified, searched application of Clean Development mechanism(CDM) approved methodology. If the methodologies apply to GHG reduction activities such as application of digestion gas, heat pump system using the wastewater as heat source, hydropower using the methodology determined CDM applicability, otherwise through several assumptions calculated expectable GHG reduction emissions and determined CDM applicability. As a result, the order of calculated GHG reduction emission showed that collected and energy generation of digestion gas is 66,775 tCO2/yr, gas engine cogeneration system is 8,182 tCO2/yr, heat pump system using the wastewater as a heat source is 72,715 tCO2/yr, and hydropower is 561 tCO2/yr. Consequently, the order of calculated Certified Emission Reductions(CERs) benefit showed that heat pump system using the wastewater, as a heat source is 1,381 million won/yr was estimated as the highest, followed by a collected and energy generation of digestion gas is 1,268 million won/yr.

대한상하수도학회 `99 정기총회 및 학술발표회 / 보고 및 논문 : 공존이온의 차이에 의한 NF membrane 이온 투과성에 대한 고찰

김상욱,최승일 대한상하수도학회 1999 1999년도 정기총회 및 학술발표회 Vol.- No.-

농축(Thickening)에서 계면형성 메커니즘에 대한 수리동역학적 해석

한무영,송재민 대한상하수도학회 2001 상하수도학회지 Vol.15 No.2

There is an enormous gap between the practice and theory in understanding the thickening process, and neither can explain the thickening process satisfactorily. The special feature of thickening process is the creation of a well-defined solid-liquid interface as they settle. In this paper, the mechanism of interface formation during the sedimentation of concentrated suspension (thickening) is investigated hydrodynamically from a microcosm consisting of four particles in a same plane and smaller particle below. The trajectories of the five particles are calculated from superposition of the pairwise two particle hydrodynamic mobility tensor. The critical separation distances are calculated as a function of particle size ratio and the separation distance. Thus, the mechanism of interface formation can be explained. This conforms to the trend of existing observations of suspension behavior.

해수담수화 전처리로서 DAF공정에서 고온의 해수에 대한 영향 특성

박현진,독고석 대한상하수도학회 2012 상하수도학회지 Vol.26 No.6

Flocculation and flotation are used as pretreatment steps prior to the reverse osmosis (RO) process. During seawater treatment, high temperature can change the water chemistry of seawater during the process of coagulation. It also affects bubble volume concentration (BVC) and bubble characteristics. Coagulants such as alum and ferric salts at 40 ℃ can also change flux rates in the seawater reverse osmosis (SWRO) process. In this study, the bubble characteristics in dissolved air flotation (DAF), used as a SWRO pretreatment process, were studied in synthetic seawater at 20 ℃ and 40 ℃. The flux of an RO membrane was monitored after dosing the synthetic seawater with coagulants at different temperatures. Results showed that BVC increases as the operating pressure increases and as the salt concentration decreases. The bubble size released at 40 ℃ is far smaller than that at 20 ℃. The addition of a ferric salt is effective for turbidity removal in synthetic seawater at 20 ℃; it is more effective than alum. When synthetic seawater was dosed with a ferric salt, the RO membrane flux increased by 27 % at 40 ℃.

상하수도시설에 대한 전과정관리(LCM)시스템 구축방안 연구

박지형,김영운,박광호,황용우 대한상하수도학회 2012 상하수도학회지 Vol.26 No.2

Water supply and sewerage systems are the large-scale urban infrastructure ejecting large amount of environmental load over the life-cycle. Therefore, it is important not only to optimize in the aspect of economical superiority and process efficiency but also to consider earth scale environmental impact. This study aimed to suggest the establishment of life cycle management(LCM) system as an integrated management solution in urban water supply and sewerage systems. As a result, the methodology for LCM system consisting of life cycle assessment(LCA), life cycle cost(LCC), life cycle CO2(LCCO2) and life cycle energy(LCE) was developed. Also, several case studies using the latest statistics data of water supply and sewerage systems were carried out to investigate the field applicability of LCM.