• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 침지형 분리막을 이용한 수처리 시스템 Water Treatment System Using Submerged Membranes
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• pp.15-41
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• 2000

• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 침지형 분리막을 이용한 수처리 시스템 Water Treatment System Using Submerged Membranes
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• pp.141-171
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• 2000

• 수산해양기술연구
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• 제51권1호
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• pp.94-101
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• 2015

The heat treatment machine based on immersion was developed to reduce temperature difference during netting process and appraised it performance compared current heat treatment machine using high pressure. It was also reviewed the optimum heat treatment procedures for PBSAT monofilament net in accordance with the immersion time and temperature. The procedure was based on physical measurement such as breaking load, elongation and angle of the mesh for PBSAT monofilament. The water temperature gap of the treatment machine based on immersion was less than $1^{\circ}C$. and the energy consumption was also increased in high temperature condition. It was identified that the optimum temperature was $75^{\circ}C$ and its optimum processing time was between 15 minutes and 20 minutes to get qualified physical properties.

• 상하수도학회지
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• 제22권1호
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• pp.79-86
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• 2008

In Korea, most of the drinking water treatment relied upon the availability of the surface water, of which the raw water quality varied significantly by season and location. Therefore, the comparison of two operation modes (Pressurized type and Submerged type membrane system) must be estimated before the long-term establishment of two systems. In this study, two pilot-scale microfiltration systems with the capacity of $50m^3/day$ were installed and operated in two different modes, and the applicability of the system was determined based on the results such as the TMP (Trans-Membrane Pressure) and flux. For quantitatively comparing the two systems, a new concept, DRF (Differential Resistance Fraction) was introduced. The accumulated sum of the permeate after each cycle of chemical cleaning was also used as a tool for the system comparison.

• 한국환경보건학회지
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• 제23권3호
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• pp.85-90
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• 1997

The objective of this study was to investigate biodegradation of TPA(terephthalic acid) and EG (ethylene glycol), treatment efficiency of polyester weight loss wastewater and microbial characteristics by aerated submerged biolfilm(ASB) p.rocess. In a batch reactor, pH increased from 7.0 to 8. 5 in the biodegradation of TPA. Whereas, in case of EG, decreased from 7.0 to 5.2. COD concentration rapidly decreased within 24hr in the biodegradation of TPA and EG. COD removal velocity constant(k) were 0.065-0.088 hr$^{-1}$. The biodegradation velocity of TPA was 1.4 times faster than that of EG. The ratio of suspended biomass to the total biomass in the reactor was 18.3-33.3%, increased as a high ratio of EG content. Biofilm thickness, biofilm dry density and attached biomass were 346-432 $\mu$m, 41.8-61.9 mg/cm$^3$, 1.45-2.67 mg/cm$^2$, respectively. There values increased as a high ratio of TPA content. In the hydraulic retention time of 36 hr, organic loading rate of 4 kgCOD/m$^3\cdot$ day and packing ratio of 70%, the effluent concentrations of TCOD, SCOD in a continuous flow reator were 1,388 mg/l, 147 mg/l and removal efficiencies were 77%, 97.6%, respectively.

• 환경위생공학
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• 제23권3호
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• pp.23-30
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• 2008

This study was carried out to get efficient of nutrient removal effects on the treatment of paper making wastewater using submerged biological film process. The concentration of average BOD at raw wastewater was $324mg/{\ell}$ and COD was $435mg/{\ell}$. The average BOD of effluent was maintained $24.2mg/{\ell}$ and average COD was $37mg/{\ell}$. The concentration of average T-N at raw wastewater was $16.5mg/{\ell}$ and T-P was $1.2mg/{\ell}$. The average T-P of effluent was maintained $2.3mg/{\ell}$ and average T-P was $0.08mg/{\ell}$. The concentration of average SS at influent wastewater was $263mg/{\ell}$. The average SS of effluent was maintained $28.2mg/{\ell}$. The result of this experiment was wastage sludge did generated and the removal efficiency of nutrients were kept equilibrium.

• Ocean and Polar Research
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• 제22권1호
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• pp.45-56
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• 2000

Hydrodynamic mixing characteristics of submerged effluent discharges into Masan Bay were investigated by both field observations and numerical model simulations. CORMIX model, a length-scale mixing model, was adopted to obtain the near-field dilution and wastefield characteristics of the effluent discharges into Masan Bay. Model predictions of the near-field dilution rates were in a good agreement with field observations in summer and winter seasons. Seasonal variations in the dilution rates showed that the highest dilution rate was obtained in winter while the lowest dilution rate was in summer. As the effluent discharges are increased with the treatment capacity expansion to be completed by 2011, the dilution rates are expected to be much reduced and the near-field stability of the wastefields will become unstable due to the increased effluent discharges.

• 한국유기농업학회지
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• 제21권3호
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• pp.403-411
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• 2013

본 연구에서는 왕우렁이를 이용한 벼 친환경 재배시 왕우렁이에 피해가 되지 않으면서 중간낙수에 의하여 벼 생육을 촉진하는 것이 가능한지 검토하고자 수행하였다. 낙수기간에 따른 토양수분함량과 왕우렁이의 생존율을 온실에서 포트실험을 통하여 조사한 결과, 토양 수분함량은 낙수 후 6일에 39.1%, 9일에 31.9%, 12일에 26.8%, 15일에 21.8%로 감소되었고, 왕우렁이는 치패의 경우 낙수 처리 후 12일까지, 중패는 낙수 처리 후 9일까지 100%의 생존율을 보였고, 낙수 후 15일에는 치패는 93.3%, 중패는 83.3%의 생존율을 보였다. 잡초발생량은 상시담수구와 중간낙수구간에 차이가 없었으며, 중간낙수에 의하여 주당 수수가 증가하여 중간낙수구의 쌀 수량은 511kg/10a로 상시담수구의 쌀수량 445kg/10a보다 66kg/10a 증가한 결과를 보였다.

• 한국물환경학회지
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• 제25권1호
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• pp.120-124
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• 2009

This study was performed to investigate the application of submerged membrane bioreactor (MBR) system for biological nutrient removal of municipal wastewater. MBR bioreactor consists of four reactors such as anaerobic, stabilization, anoxic and submerged membrane aerobic reactors with two internal recycles. The hydraulic retention time (HRT), sludge retention time (SRT) and flux were 6.2 hr, 34.1 days and $19.6L/m^2/hr$ (LMH), respectively. As a result of operation, the removal efficiency of $COD_{Cr}$, SS, TN and TP were 94.3%, 99.9%, 69.4%, and 74.6%, respectively. There was no significant effect of microbial activity after the maintenance cleaning using 200 mg/L of NaOCl. Membrane filtration for the treatment of municipal wastewater was performed for longer than 9 months without chemical recovery cleaning.

• 전산구조공학
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• 제9권3호
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• pp.125-134
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• 1996

건물기초를 지진절연하면 건물뿐만 아니라 그 내부구조물의 지진응답도 크게 감소한다는 사실이 많은 연구를 통해 확인되어 왔다. 그런데 이러한 내부구조물이 유체내에 잠기고 부가질량효과가 크게 작용되는 조건에 놓이는 경우 오히려 지진응답이 증가할 수 있다. 본 논문은 건물 내 수중구조물의 지진해석을 통해 그러한 예를 제시하고자 한다. 해석결과 지진절연된 건물의 경우 이러한 내부 수중구조물의 지진응답이 상당히 증가할 수 있기 때문에 이에 대한 조치가 필요함을 보였고, 적절한 설계에 의하여 부가질량효과를 조절함으로써 어느정도 응답을 줄일 수 있다는 사실을 알 수 있었다.