• 한국물환경학회지
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• 제22권5호
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• pp.865-870
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• 2006

The behavior and influence of EPS on membrane fouling by changing of hydraulic retention time was investigated, using lab. scale submerged membrane bio-reactor, which was operated with gravitational filtration and fed supernatant of primary sedimentation in waste water treatment plant as influent. The membrane was adopted micro-filter of polyethylene hollow fiber. EPS was analysed as polysaccharides and protein especially, into soluble and bound EPS separately. The concentration of soluble EPS was increased at short HRT, then membrane fouling was rapidly progressed and flux was depressed. The most of EPS clogged membrane pore were polysaccharides, while protein was important parameter affected on membrane fouling because of it's more accumulating in the more term operating.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 심포지움시리즈 Jan-99 막분리공정을 이용한 재활용 기술
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• pp.1-12
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• 1999

In Kimchi (a salt-pickled and fermented food) manufacturing industry, the process of brining and rinsing the raw vegetable produces a vast amount of wastewater of high salinity. Instead of expensive and low-efficient conventional treatment system, brining wastewater reuse system was developed using hybrid chemical precipitation / microfiltration. In the microfiltration of chemically treated brining wastewater, comparison of flux, backwashing frequency and energy consumption was made between dead-end and crossflow filtration mode. The optimum location of neutralization step in this system was also discussed in connection with the micro filtration performance. The quality test of Kimchi prepared by the reuse system conformed the new approach was successful in terms of water/raw material (salt) savings and wastewater reduction.

• 상하수도학회지
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• 제18권6호
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• pp.770-777
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• 2004

Three pilot-scale membrane systems were operated using lake water as influent in this study. Microfiltration (MF) membrane with pore size of 0.01 m was used in Systen I of which filtration mode was set at constant pressure of $1kgf/cm^2$. Ultrafiltration (UF) membranes with molecular cutoff (MWCO) of 80,000 and 13,000 were used in System II-1 and II-2, respectively. Constant flow mode was applied at the range between 0.7 and $1.5m^3/m^2{\cdot}d$ (average of $1.1m^3/m^2${\cdot}d) for System II-1 and between 0.37 and $1.65m^3/m^2{\cdot}d$ (average of $1.18m^3/m^2{\cdot}d$) for System II-2. In System I, the flux changed from $1m^3/m^2{\cdot}d$ to $0.2m^3/m^2{\cdot}d$ during the operation time of 5 months. System II showed recovery of 94% under the allowable maximum pressure of $3kgf/cm^2$ during the same operation period. From these results, the efficient operation was observed in constant flow mode with respect to filtration time and recovery. Average filtrate turbidity showed 0.0071 NTU in System I and 0.0054 NTU in System II, which implied that high turbidity removal was obtained in both MF and UF systems with no significant difference between MF and UF. From the fact that membrane flux depends largely on membrane type and operation mode, a guideline of optimum design and operation should be suggested for application of membrane systems to full scale water treatment.

• 한국물환경학회지
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• 제35권5호
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• pp.409-417
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• 2019

In this study, a $480m^3/day$ pilot device was constructed through laboratory experiments based on the Ministry of Environment manual. The purpose of this study was to analyze the characteristics of CSO treatment and backwashing characteristics by applying the pilot device to the field. The purpose of this study was to acquire the basic data necessary for the design and operation management of the real scale filtration type non-point pollution control system. The filtration was conducted while maintaining the linear velocity of 20m/hour. The CSO treatment efficiencies of the pilot devices were 0.4-76.1%(mean 49.0 %), SS 51.4-91.6%(mean 77.8%), COD 22.2-59.4% (mean 38.3%) and TP 14.5-52.6%(mean 38.1%),respectively. The correlation coefficient between SS and the turbidity of influent water was 0.90, higher than that of CSO. To operate the treatment system effectively, the turbidity can be easily measured in real time as the monitoring item is the most appropriate because SS is the main target substance of the non-point source. As a result of analyzing the adsorbent treatment characteristics of PP filter material applied to this pilot device, the average particle diameter range of influent was $4.6-40.1{\mu}m$(mean $21.2{\mu}m$) and the treated water was $0.9-24.5{\mu}m$(mean $6.4{\mu}m$), respectively. Particles of approximately 10m or less are leached out, and so it is necessary to compensate for the raw water containing micro particulate matter.

• 한국세라믹학회지
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• 제31권4호
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• pp.359-366
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• 1994

Tow types of supports were made using $\alpha$-Al2O3 powder and optimum conditions to prepare for supports were provided. Sol solution for coating was synthesized by sol-gel method with aluminum isopropoxide. Supports were coated and heat-treatemented, where the thickness of coating layer was controlled by dipping time. Flux and permeability of alumina membrane were measured by liquid and gas filtration apparatus and these were compared with the provided model. It was confirmed that the coating was done very well without micro~crack and defect.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 반도체재료
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• pp.34-37
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• 2001

As the integrated circuit device shrinks to smaller dimensions, chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric (IMD) layer with free-defect. However, as the inter-metal dielectrics (IMD) layer gets thinner, micro-scratches are becoming as major defects. Micro-scratches are generated by agglomerated slurry, solidified and attached slurry in pipe line of slurry supply system. To prevent agglomerated slurry particle from inflow, we installed 0.5${\mu}m$ POU (point of use) filter, which is depth-type filter and has 80% filtering efficiency for the $1.0{\mu}m$ size particle. In this paper, we studied the relationship between defect generation and pad count to understand the exact efficiency of the slurry filtration, and to find out the appropriate pad usage. Our preliminary results showed that it is impossible to prevent defect-causing particles perfectly through the depth-type filter. Thus, we suggest that it is necessary to optimize the flow rate of slurry to overcome depth type filters weak-point, and to install the high spray of de-ionized Water (DIW) with high pressure.

• 유기물자원화
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• 제11권3호
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• pp.51-59
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• 2003

본 연구에서는 베타글루칸 생산공정에서 발생하는 공정수에 대한 M/F(micro filtration) 분리막 시스템의 효용성을 검토하였다. M/F 시스템의 운전을 위하여 M/F 분리막은 Millipore(USA)사의 Pellicon 2 Cassette Filter Module HVMP $0.45{\mu}m$를 사용하였다. 플럭스는 운전압력의 상승에 따라서는 증가하며, 운전시간의 경과에 따라서는 감소하였다. 농축비가 높을수록 농축액에 남아있는 베타글루칸 제품의 회수가 효과적이었다. 베타글루칸 발효액의 재이용시 투과액의 전환수율이 42.5%로 배양 패턴에 큰 변화가 없었다. 본 연구에서 얻어진 결과를 토대로 청정생산공정에서 투과액을 반응공정수로 재이용 가능하리라 판단된다.

• 한국식품영양과학회지
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• 제29권6호
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• pp.1035-1041
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• 2000

멸치 액젓의 새로운 위생화 방법으로 감마선 조사기술을 이용하였고, 산업적 생산에 응용하고자 기존의 가열살균 및 정밀여 과방법과 비교하여 미생물학적, 이화학적 및 관능적 품질변화를 조사하였다. 감마선을 조사한 멸치 액젓은 미생물 제어에 효과적 인 것으로 나타났으며 조사선량이 증가함에 따라 색이 밝아지는 등 외관적으로 긍정적인 효과를 보였다. 또한 저장 기간 중 pH, 염도 및 점도 등의 변화 없이 품질이 유지되었고, 색, 향, 맛 및 종합적 기호도 등 관능적 측면에서도 대조구와 가열살균 시험구에 비해 높은 선호도를 나타내어 정밀여과 시험구와 마찬가지로 우수한 품질을 나타내었다 감마선 조사구 중 5kGy의 선량을 적용할 때 미생물학적 및 관능적 품질이 가장 적합한 것으로 나타났다. 따라서 멸치액 젓 에 감마선을 조사함으로써 가열살균 및 정밀여과 방법과 비교할 때 품질의 변화 없이 우수한 멸치 액젓을 생산할 수 있었으며, 산업적 대규모 생산에 새로운 위생화 기술로서 이용할 수 있는 가능성을 제시하였다.

• 멤브레인
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• 제17권2호
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• pp.112-117
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• 2007

The application of membrane bioreactors for the depuration of wastewater coming from the washing of mineral oil storage tanks is described. Microfiltration hollow-fibre membranes were used in the submerged configuration. Filtration tests were carried out with a biomass concentration of about 15 g/L in order to assess the critical flux of the hollow fibre membrane used. Then particular care was taken in carrying out the performance runs in the sub-critical flux region. The reactor performance was very high, with removal efficiencies ranging between 93% and 97% also when the concentration of hydrocarbon was very high. Some kinetic parameters for the COD and the hydrocarbon removal were estimated.

• 대한기계학회논문집A
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• 제32권8호
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• pp.617-623
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• 2008

The membrane filter adhered with nanostructured porous layer was made by heat treatment after deposition of nanoparticle-agglomerates sintered in aerosol phase onto a conventional micron-fibrous metal filter as a substrate filter. The Sintered-Nanoparticle-Agglomerates-coated NanoStructured porous layer Membrane Filter (SNA-NSMF), whose the filtration performance was improved compared with the conventional metal membrane filters, was developed by adhesion of nanoparticle-agglomerates of dendrite structure sintered onto the micron-fibrous metal filter. The size of nanoparticle-agglomerates of dendrite structure decreased with increasing the sintering temperature because nanoparticle-agglomerates shrank. When shrinking nanoparticle-agglomerates were deposited and treated with heat onto the conventional micron-fibrous metal filter, pore size of nanostructured porous layer decreased. Therefore, pressure drops of SNA-NSMFs increased from 0.3 to 0.516 kPa and filtration efficiencies remarkably increased from 95.612 to 99.9993%.