• Journal of the Korean Professional Engineers Association
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• v.29 no.1
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• pp.46-52
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• 1996

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.10a
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• pp.175-176
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• 1999

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.503-515
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• 2014

A lot of existing wastewater treatment plants (WWTPs) are rebuilt or retrofitted for advanced wastewater treatment processes to cope with reinforced effluent criteria of nitrogen and phosphorous. Moreover, how to treat the wasted sludge from WWTPs has been also issued since the discharge of the wasted sludge into ocean is impossible from 2011 due to the London Convention 97 protocol. These trend changes of WWTPs get a motivation to assess environmental and economic impacts from the construction stage to the waste stage in WWTPs. Therefore, this study focuses on evaluation of environmental and economic impacts of the advanced wastewater treatment processes and waste sludge treatment process by using life cycle assessment. Four advanced wastewater treatment processes of Anaerobic/Anoxic/Oxic ($A_2O$), 5 stages-Bamard Denitrification Phosphate (Bardenpho), Virginia Initiative Plant (VIP), and Modified University of Cape Town (MUCT) are chosen to compare the conventional activated sludge (CAS) and three waste sludge treatment methods of land fill, incineration, and composting are used. To evaluate environmental and economic impacts of each advanced wastewater treatment processes, life cycle assessment (LCA) and life cycle cost (LCC) are conducted based on International organization for standardization (ISO) guidelines. The results clearly represent that the $A_2O$ process with composting shows 52% reduction in the environmental impact than the CAS process with landfill. On the other hand, the MUCT process with composting is able to save 62% of the life cycle cost comparing with the CAS process with landfill. This result suggested the qualitative and quantitative criteria for evaluating eco-environmental and economic technologies of advanced treatment processes and also sludge treatment method, where their main influence factors on environmental and economic impacts are analyzed, respectively. The proposed method could be useful for selecting the most efficient and eco-friendly wastewater treatment process and sludge treatment method when retrofitting the existing WWTPs to advanced treatments.

• Journal of Navigation and Port Research
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• v.38 no.5
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• pp.451-456
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• 2014

Lab scale experiment was carried out to study biological wastewater treatment technology developed for shipboard. RCM process using BM(Beneficial Microorganisms) was investigated for practical application on shipboard sewage treatment. RCM process is an environmental friendly treatment system, with minimum production of sludge. In the test, BOD5, CODcr, T-N and T-P were reduced a 96%, 97%, 78% and 81.68% respectively. From the result it was suggested that RCM process with BM might be a suitable process for shipboard sewage treatment, maintenance of useful microorganisms and creating special environment as the SDC tank is circulating in the non-biodegradable organics sludge generated during the wastewater treatment, thus reducing the amount of sludge generated. Therefore, the RCM process does not require additional equipment to strengthen it to meet the marine pollution standards.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.45-48
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• 2006

혼합유류(등,경유)로 오염된 대상부지의 토양특성을 파악하여 세척공법의 적용성을 판단하고, 적용성시험을 통하여 장치별 설계인자를 도출하였다. 시험결과 본 세척대상토양의 경우 계면활성제와 같은 첨가제를 주입하지 않고 물리적인 탈착공정만을 거쳐도 90%이상의 오염물질이 토양입자표면으로부터 탈착됨을 알 수 있었으며, 이를 반영하여 장치를 제작, 설치하였다. 세척대상 오염토량은 총 $12,225m^3$, 사업수행기간은 약 6개월, 세척장치에 주입된 세척토양의 평균오염농도는 약 3,152ppm 이었으며 세척 완료된 토양의 평균농도는 약 150ppm으로 약 97%의 제거효율을 보여 복원목표인 800ppm을 만족시킬 수 있었다. 그리고, 세척토양의 입도분포를 정확히 파악하고 분리시킬 토양입자 크기를 결정하여 현장 적용한 결과 세척공법으로부터 배출되는 응집슬러지를 최소화할 수 있었으며, 발생되는 세척폐수 또한 세척수 처리시스템을 거쳐 재활용 할 수 있도록 하였다. 이런 결과를 통하여 세척공법이 다른 Ex-situ 공법과 비교하였을 경우 현장의 적용성, 경제성, 복원기간 등을 감안하였을 경우 성공적인 세척공법의 적용사례라 할 수 있다.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.71-81
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• 2005

Anaerobic digestion is employed worldwide as the oldest and most important process for sludge stabilization. An additional advantage is the production of methane during anaerobic digestion. However, the waste activated sludge(WAS) has poor anaerobic degradability and less gas production due to the cell wall of bio-solid. In order to improve and enhance stabilization and dewatering of the WAS, a number of pretreatment processes have been developed and investigated. In this research, a pilot-scale study of pulse power pretreatment was performed to improve anaerobic degradability and dewaterability of the WAS. A pilot plant was designed and operated based on a previous laboratory study. Change of the sludge characteristics by pulse power pretreatment was estimated to assess the increasing soluble organics. The increased soluble organics could be used as a good substrate in the anaerobic digesion process. Gas production and methane potential of the anaerobic digestion were estimated as the parameters of anaerobic degradability. For evaluation of the dewaterability of pretreated WAS, capillary suction time(CST) and specific resistance were measured. The efficiency of energy recovery was also estimated by calculating energy balance.

• Environmental engineer
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• s.169
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• pp.65-73
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• 2000

1999년 G-7 환경공학기술개발사업의 일환으로 CNR공법을 이용한 하수처리장의 탈질, 탈인을 위한 상용화기술개발연구의 결과를 요약하면 다음과 같다. 1999년 3월부터 1999년 12월 16일까지의 실험기간 중 1톤 PILOT 반응조와 2000년 1월 18일부터 2000년 4월 30일까지의 실험기간 중 구리하수처리장에 설치한 50톤 PILOT의 운전결과는 다음과 같다. CNR공법은 우리나라의 일반적인 하수성상에서 운전관리가 원활하면 동절기와 유기물 부

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.31-44
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• 1985

The application of anaerobic attached microbial films in the expanded bed process has recently been examined at high temperatures ($55^{\circ}C$) and with particulate matter. Extrapolation of the kinetics suggested that waste activated sludge (WAS) could be efficiently digested at hydraulic retention times as short as six hours in the expanded bed process. This would represent a 99 percent digester reactor volume reduction and would introduce interesting solids management alternatives if such a high rate process were developed. This paper presents a summary of a 1.5 year study of the feasibility of such a process. Three continuously fed $55^{\circ}C$ laboratory reactor systems were used to define the kinetics and the site of reactions-control completely mixed reactors were compared to the expanded beds (AAFEB) with and without a hydrolysis unit preceding the attached film unit. Well defined laboratory-generated WAS was compared to actual WAS from a domestic sewage treatment facility. Sixty percent of the biodegradable organics were converted in an AAFEB at a 15-hour hydraulic retention time without hydrolysis, whereas greater than 95 perccent of the biodegradable organics were stabilized in a two-stage system consisting of a 3-day HRT hydrolysis reactor followed by a 15-hour HRT AAFEB. The limitations of this high rate process and its potential application are discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.19-31
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• 1982

The purpose of the research is to investigate the applicability of the filter activated sludge process for the treatment of toxic phenolic wastewaters. The experiment for the research was carried out by continuously feeding synthetic phenol wastewater for four periods, and the results show that a synthetic fiber filter is an adequate material for filter activated sludge process when taking consideration of durability, SS removal efficiency and wastewater permeability. The permeability of the filter sharply decreases when the temperature of the reactor is below $10{\sim}15^{\circ}C$ for a long period. In filter activated sludge process, even under high volumetric loading conditions, high phenol removal efficiencies can be attained due to the high microbial sludge concentration in the reactor and consequently low F/M ratio. In this research, the effluent phenol concentration were checked to be below $0.1mg/{\ell}$ at the influent phenol concentrations of $63{\sim}468mg/{\ell}$. During the research very low microbial yield coefficients, 0.035~0.160 kg SS/kg COD removed, were observed and the temperature coefficient for aerobic sludge digestion was measured to be 1.021.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.234-238
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• 2008

Coarse pore filter could be an alternative of membrane for solid-liquid separation in an activated sludge reactor because of inexpensive cost of the filter material and high flux at low filtration pressure. However such filter module has much less specific filtration area compared to the membrane. Therefore a certain effort is required to increase the specific filtration area in the module design of such coarse pore filter for solid-liquid separation in an activated sludge reactor. In this study, tubular type coarse pore filter was designed at various diameter and configuration. The filtration performance was investigated to separate solid in the activated sludge reactor for domestic wastewater treatment. Tubular type coarse pore filter module could be successfully applicable to solid separation in the activated sludge reactor. The design parameters were the tube diameter of 10mm and vertical installation. Smaller diameter of the tube caused faster increase of the filtration pressure because of the hydraulic head loss in the tube channel.