• 한국막학회:학술대회논문집
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• 한국막학회 1993년도 춘계 총회 및 학술발표회
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• pp.41-41
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• 1993

Recently, the advanced membrane separation technology has even been applied to the post treatment to biological process of wastewater treatment, since the efficiency of biological treatment significantly depends on maintaining a high biomass concentration in the bioreator. Particularly, anaerobic microbes in the biological system have slower growth rates than aerobic microbes and thus it takes a long hydaulic retention time(HRT) to prevent biomass washout in the completely mixed anaerobic digester. The anaerobic sludge also has poor settleability owing to its diffusible and somewhat filamentous nature. Moreover, the residual gasification and consequent sludge rise in the clarifier compartment become a considerable problem, which proves that complete separation of biological solids is difficult.

• 상하수도학회지
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• 제27권5호
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• pp.529-545
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• 2013

With the increasing concern on climate changes and energy shortage, anaerobic membrane bioreactors (AnMBR) become a promising alternative to aerobic processes for domestic wastewater treatment. Two major advantages of AnMBRs are energy production and sludge reduction. Recently, several different configurations of AnMBRs have been proved to produce high quality effluent at reasonable hydraulic retention time and ambient temperature. One of the major problems of the AnMBR is membrane fouling control, and some solutions are already suggested. Other problems to be solved before the full application of the AnMBR are recovery of dissolved methane, management of residual nutrients and sulfide. Considering the potential advantages and future technology development, AnMBR will become major domestic wastewater treatment process in near future.

• 멤브레인
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• 제21권4호
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• pp.360-366
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• 2011

음식물 폐기물 침출수를 처리하는 분리막 결합 고온 혐기성소화공정(생물학적 반응조) (Anaeorobic Membrane Bioreactor, AnMBR)의 파일럿 운전에서 분리막의 교차여과 속도와 막간압력이 파울링에 미치는 영향을 관찰하였다. 연구 결과 정압여과 하에서 교차여과 속도가 증가할수록 파울링의 속도는 현격히 감소되었다. 그러나 이와 같은 영향은 낮은 막간압력에서 더욱 효과적이었다. 막간압력이 증가할수록 여과대상 물질의 압축성으로 인해 투과성이 상대적으로 낮은 파울링층(혹은 케익층)이 분리막 표면에 형성된 것에 기인된 듯하다. 여과대상 시료의 입도분석을 해 본 결과 입자크기는 약 $10{\sim}100{\mu}m$ 범위에서 분포하였고 이에 따라 브라운확산에 의한 역수송보다 분리막 표면에서 교차여과에 의해 발생하는 전단력이 입자의 역수송에 더욱 기여하고 있음을 예측할 수 있었으며 이는 AnMBR의 연속운전을 통해 재확인할 수 있었다. 운전 후 막 부검을 실시한 결과 유기 및 무기 파울링이 모두 관찰되었으나 어느 것이 지배적인 파울링 기작을 나타내는지는 앞으로 더욱 연구가 필요하다. 무기 파울링의 경우 대부분 분리막 표면에서 스케일링 형성이 지배적이었으며, 따라서 분리막의 공극 막힘에 주로 기여하는 작은 콜로이드성 유기물질의 경우 분리막 표면에서 전단력에 의한 역수송 효과는 그다지 크지 않을 것으로 사료된다.

• 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.

• 한국물환경학회지
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• 제27권3호
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• pp.322-328
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• 2011

This study was performed to investigate the characteristics of nutrient removal of municipal wastewater in the membrane bioreactor system with the different types of membrane. Membrane bioreactor consists of three reactors such as two intermittent anaerobic and the submerged membrane aerobic reactor with flat sheet and hollow fiber membrane, respectively. The removal efficiencies of $COD_{cr}$, BOD, SS, TN and TP on the flat sheet membrane bioreactor were 94.3%, 99.0%, 99.9%, 70.3% and 63.1%, respectively. In addition, The removal efficiencies of $COD_{cr}$, BOD, SS, TN and TP on the hollow fiber membrane bioreactor were 94.0%, 99.3%, 99.9%, 69.9% and 66.9%, respectively. The estimated true biomass yield, specific denitrification rate (SDNR), specific nitrification rate (SNR) and phosphorus removal content on the flat sheet membrane bioreactor were $0.33kgVSS/kgBOD{\cdot}d$, $0.043mgNO_3-N/mgVSS{\cdot}d$, $0.031mgNH_4-N/mgVSS{\cdot}d$, and 0.144 kgP/d, respectively. In addition, the estimated true biomass yield, specific denitrification rate (SDNR), specific nitrification rate (SNR) and phosphorus removal content on the hollow fiber membrane bioreactor were $0.30kgVSS/kgBOD{\cdot}d$, $0.067mgNO_3-N/mgVSS{\cdot}d$, $0.028mgNH_4-N/mgVSS{\cdot}d$, and 0.121 kgP/d, respectively. There was little difference between the flat sheet and hollow fiber on the nutrient removal efficiencies except SNR and SDNR. These differences between them were caused by the air demand to prevent the membrane fouling. The flux and oxygen demand for air scouring were $19.0L/m^2/hr$ and $2.28m^3/min$ for the flat sheet membrane, and $20.7L/m^2/hr$ and $1.77m^3/min$ for the hollow fiber membrane on an average.

• 한국물환경학회지
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• 제21권5호
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• pp.464-469
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• 2005

In the nonwoven fabric filter bioreactor (NFBR), both the construction and the operation costs could be saved because a high concentration of microorganism can be maintained in the reactor as in the membrane bioreactor. However, the NFBR process has been investigated only under aerobic and/or anoxic conditions, In this research, a basic anaerobic treatment experiment was performed at $35^{\circ}C$ by feeding an airtight NFBR with a concentrated synthetic organic wastewater. The organic loading rate (OLR) of the NFBR was increased stepwise from $0.25kg\;COD/m^3-day$ to $0.77kg\;COD/m^3-day$ by gradually decreasing the hydraulic retention time from 20 days to 13 days. The results of the research showed that the best COD removal efficiency achieved at the OLR of $0.67kg\;COD/m^3-day$ with a value of 99.3%. The methane content of the produced gas was highest with a value of 61.2% at the OLR of $0.33g\;COD/m^3-day$. The highest methane production rate was $0.89g\;COD/m^3-day$ at the same OLR. The operation was terminated at the OLR of $0.77kg\;COD/m^3-day$ because of the deterioration in COD removal efficiency, gas production rate, and the methane content of the gas. Further researches are recommended for the NFBR to be employed for anaerobic treatment of organic wastewaters.

• Membrane and Water Treatment
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• 제3권2호
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• pp.113-121
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• 2012

Up-flow multi-layer bioreactor (UMBR) is a hybrid system using dual sludge that consists of an up-flow multi-layer bioreactor as anaerobic/anoxic suspended growth microorganisms followed by an aeration tank. The UMBR acts as a primary settling tank, anaerobic/anoxic reactor, thickener which requires low energy due to mixing by up-flow stream. This study focused on using a pilot UMBR plant with capacity of 20-30 $m^3$/day for domestic wastewater in HCMC. HRTs of UMBR and aeration tank were 4.8 h and 7.2 h, respectively. The average MLSS of UMBR ranged from 10,000-13,600 mg/l SS. Internal recycle rate and sludge return were 200-300% and 150-200%, respectively. The results obtained from this study at flow rate of 20 $m^3$/day showed that removal of COD, SS, TKN, N-$NH_4$, T-N, and color were 91%, 87%, 86%, 80%, 91% and 91%, respectively.

• 한국환경과학회지
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• 제28권10호
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• pp.899-905
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• 2019

Recently, an innovative method for wastewater treatment and nutrient removal was developed by combining the sequence batch reactor and membrane bioreactor to overcome pollution caused by shipboard sewage. This system is a modified form of the activated sludge process and involves repeated cycles of mixing and aeration. In the present study, the bacterial diversity and dominant microbial community in this wastewater treatment system were studied using the MACROGEN next generation sequencing technique. A high diversity of bacteria was observed in anaerobic and aerobic bioreactors, with approximately 486 species. Microbial diversity and the presence of beneficial species are crucial for an effective biological shipboard wastewater treatment system. The Arcobacter genus was dominant in the anaerobic tank, which mainly contained Arcobacter lanthieri (8.24%), followed by Acinetobacter jahnsonii (5.81%). However, the dominant bacterial species in the aerobic bioreactor were Terrimonas lutea (7.24%) and Rubrivivax gelatinosus (4.95%).

• 한국물환경학회지
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• 제34권1호
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• pp.121-131
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• 2018

Domestic sewage treatment plants (STPs) consume about 0.5 % of total electric energy produced annually, which is equivalent to 207.7 billion Korean won per year. To minimize the energy consumption and as a way of mitigating the depletion of energy sources, the sewage treatment strategy should be improved to the level of "energy positive". The core processes for the energy positive sewage treatment include A-stage for energy recovery and B-stage for energy-efficient nitrogen removal. The integrated process is known as the A/B-process. In A-stage, chemically enhanced primary treatment (CEPT) or high rate activated sludge (HRAS) processes can be utilized by modifying the primary settling in the first stage of sewage treatment. CEPT utilizes chemical coagulation and flocculation, while HRAS applies returned activated sludge for the efficient recovery of organic contents. The two processes showed organic recovery efficiencies ranging from 60 to 70 %. At a given recovery efficiency of 80 %, 17.3 % of energy potential ($1,398kJ/m^3$) is recovered through the anaerobic digestion and combustion of methane. Besides, anaerobic membrane bioreactor (AnMBR) can recover 85% of organic contents and generate $1,580kJ/m^3$ from the sewage. The recovered energy is equal to the amount of energy consumption by sewage treatment equipped with anaerobic ammonium oxidation (ANAMMOX)-based B-stage, $810{\sim}1,620kJ/m^3$. Therefore, it is possible to upgrade STPs as efficient as energy neutral. However, additional novel technologies, such as, fuel cell and co-digestion, should be applied to achieve "energy positive" sewage treatment.

• 대한환경공학회지
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• 제33권7호
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• pp.485-491
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• 2011

본 연구는 2개의 간헐혐기조, 막분리호기조 및 슬러지 가용화로 구성된 유로변경형 membrane bioreactor의 운영을 통하여 도시 하수의 영양염류 제거 특성을 규명하였다. 수리학적 체류시간(HRT)과 운영 여과 플럭스의 평균값은 각각 6.5 시간과 $20.4L/m^2{\cdot}hr$ (LMH)이었으며, 공정을 운전한 결과, $COD_{Cr}$, SS, TN 및 TP의 평균 제거율은 각각 94.0%, 99.3%, 99.9%, 69.9%와 66.9%이었다. 슬러지 생산계수, SDNR, SNR, SPPR 및 SPUR은 각각 0.34 kg VSS/kg BOD d, $0.067mg\;NO_3-N/mg\;VSS{\cdot}d$, $0.028mg\;NH_4-N/mg\;VSS{\cdot}d$, 16.0 mg P/g VSS d 및 2.1 mg P/g VSS d였다. 또한, 생산된 슬러지의 평균 질소 및 인 함량은 각각 8.9%와 3.5%였다.