• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.128-131
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• 2003

The objective of this investigation was to evaluate applicability of precoat filtration for drinking water treatment. Precoat filter used in this experiment are candle filter. Element disk of candle used in this experiment are pore size 5$\mu\textrm{m}$(W), 10$\mu\textrm{m}$(R), 20$\mu\textrm{m}$(B) and 40$\mu\textrm{m}$(Y). And diatomaceous earth are cake pore size 3.5$\mu\textrm{m}$(A), 7$\mu\textrm{m}$(B) and 17$\mu\textrm{m}$(C). Filtrate of precoat filter during 30min are R-C 11.3, B-C 10.2, W-C 8.9, Y-C 8.6, Y-B 7.1, R-A 5.4(㎥/㎡). Turbidity of the effluent can be attained under 0.1NTU with the all combination.

• 한국축산시설환경학회지
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• 제20권1호
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• pp.15-20
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• 2014

The present study was conducted to develop a milk filtering system for decreasing somatic cell count (SCC) in bulk tank milk. The pore sizes of the filter were 0.1, 0.3, 0.4, 0.5 and $0.8{\mu}m$. The rate of SCC reduction of $1^{st}$ grade milk on $0.1{\mu}m$ filter was 76% and significantly higher than other treatments. The rates of SCC reduction for 0.3, 0.4, 0.5 and $0.8{\mu}m$ were 35, 32, 18 and 6.4%, respectively. The effects of the milk filtering system on bacterial count and milk fat content were minimal. The milk flow rates per minute between the filter sizes were similar. But discharge pressures were increased as the pore size of the filter decreased. In conclusion, Considering the rate of SCC reduction, discharge pressure and cost, $0.4{\mu}m$ filter could be recommended.

• 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%.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.745-748
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• 2000

Anaerobic digester coupled with hollow fiber membrane unit. Treatment of starch waste with anaerobic digester-membrane system was studied. $0.17\;m^2$ area of hollow fiber membrane unit of known pore size was immersed into laboratory-scale anaerobic digestion system. The gas production was about $0.74\;m^3/kg$ COD treated. The COD removal efficient was about 80-95% depending on the hydraulic retention time. Crossflow ultrafiltration as Post treatment to anaerobic filter. The study conducted with different membrane pore size indicated that membrane with 1,000,000 molecular weight cut-off size gave a higher COD removal efficiency in the range of 83-87% while giving a study flux of $120-130\;L/m^2\;{\cdot}\;h$. A study was conducted to see the long term clogging effect of membrane also.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.611-612
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• 2006

In a manufacturing technique of the sintered filter, pressureless sintering method has good permeability, it is not need the binder and lubricant used on compacting process, so it has little contamination and it is easy to control the pore size and shape but the mechanical strength is low relatively and it is difficult that parts of complicate form are manufactured. In the case of manufacturing the filter by press and sintering method, in order to be satisfactory characteristic of un-pressed filter, in this study sintered metal filter fabricated by using 30-40mesh stainless steel 316L powder and additive agents. Porosity and structure of pores, permeability and mechanical strength of the sintered filter were investigated with the variation sintering conditions. Porosity was nearly constant about $60{\sim}70%$, density, permeability and mechanical strength were changed markedly with quantity of additive materials and sintering conditions.

• 핵의학기술
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• 제12권1호
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• pp.74-77
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• 2008

The radiopharmaceuticals are routinely injected to blood vessel for acquiring PET image. For this reason, It is imperative that they undergo strict quality control measures. Especially, Sterility test is more important than any other quality control procedures. According to the FDA guideline, It requires filter integrity test used in the processing of sterile solutions. Among several methods, we can decide to use bubble point test. We usually use vented GS-filters (Millipore co., USA) which are sterilizinggrade (0.22 um pore size) and are placed upper site on product vial. After the synthesis of $^{18}F$-FDG, solutions wet the membrane in filter and then go into the product vial. By all synthesis steps have finished, we can observe the presence of the bubbles in the product vial. Since we have started this study, we have never found any bubbles in the product vial. Because the maximum pressure intensity of the filter which has set by manufacturer is up to 5 bars, but helium gas pressure is up to 1 bar in our module system. So, we can make 5 bars pressure using helium gas bombe and increase pressure up to 5 bars step by step. However, it does not happen to anything in vial.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 가을 학술발표회 논문집
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• pp.73-80
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• 1998

• 한국물환경학회지
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• 제30권5호
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• pp.532-538
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• 2014

A cylinder-shaped filter was developed to manage the runoff from construction sites. Compressed air was used for back-washing and pore sizes of filter were $23{\mu}m$ and $46{\mu}m$. The turbid water was prepared using sediments in construction sites. The grain size analysis showed that grains smaller than $38{\mu}m$ and larger than $335{\mu}m$ in size constituted 34.4 % and 37.6 %, respectively. Removal efficiency of the filter on turbidity, SS, COD, TN and TP showed 25~37%, 20~40%, 50~55%, 23~27% and 14~20%, respectively, whereas their removal efficiecy by using coagulant PAC showed 77~84%, 70~83%, 53~60%, 27~36%, and 59~75%, respectively. The filtration time was determined to be around 10 to 20 minutes. Back-washing for 10 seconds by pressurized air resulted in a satisfactory regeneration efficiency. According to the aforementioned test results, the cylinder-shaped filter is effective in reducing turbidity and would be suitable for practical application in construction sites and farms.

• 청정기술
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• 제24권1호
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• pp.27-34
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• 2018

분진과 질소 산화물을 동시에 처리할 수 있는 이원적 기능을 가진 촉매 필터는 산업체 적용에 많은 장점을 갖고 있다. 통기성이 높은 시트 형 세라믹 필터를 촉매 필터 소재로 활용하면 배기가스 처리 공정의 타당성을 더욱 높일 것이다. 그러나 시트 필터는 두께가 얇아서 촉매 지지층에 촉매를 부착할 수 있는 공간이 부족하므로 효과적인 촉매필터를 제조하기가 쉽지 않다. 본 연구에서는 국산 시트 필터를 사용하여 촉매 필터를 제조하고 실험실 장치에서 제조된 촉매 필터의 NO 환원 성능이 평가되었다. 현재 시판되고 있는 시트 필터로 촉매 필터를 제조할 경우 여과속도 $2m\;s^{-1}$에서 700 ppm NO 농도에 대한 NO 전환율이 92% 이하로써 촉매 필터 재료로써 좋은 특성을 나타내지 못했다. 이와 같이 저조한 특성을 보이는 이유는 시트 필터의 촉매 지지층의 기공이 균일하지 못하여 필요 이상의 큰 기공이 존재하기 대문으로 해석되었다. 필터에 존재하는 큰 기공의 사이즈를 줄이기 위하여 필터를 제조하는 원재료에 작은 입자를 혼합하여 시트 필터의 기공을 줄이는 효과를 통하여 NO 전환율 96% 이상을 달성하였다. 또한 촉매 지지체로써 큰 입자의 $TiO_2$를 혼합하여 촉매층의 기공을 팽창시켜서 개선된 촉매 필터는 상용 요구에 충족되는 98% 이상의 NO 전환율을 보였다. 위 두 경우 모두 촉매층 내에 존재할 수 있는 큰 기공을 효과적으로 메워서 적절한 촉매층이 형성되면 촉매 필터의 성능이 향상되는 결과를 보인 것이다. 따라서 이와 같이 통기도가 우수한 장점을 가진 시트 필터가 촉매 필터의 소재로 잘 활용될 수 있음을 보였다.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.133-139
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• 2010

The effects of suspended solids size on culture water quality were determined in a commercial recirculating aquaculture system (RAS) for Japanese eel, Anguilla japonica. The particulate phase of the culture water was serially divided into six size fractions using 300, 200, 100, 75, 45, and 26 ${\mu}m$ pore size stainless sieves. The total, dissolved, and particulate nitrogen and phosphorus, and suspended solids for each fraction were determined. The concentration ranges in the fractions were: total nitrogen, 164-148 mg $L^{-1}$; total phosphorus, 20.4-15.5 mg $L^{-1}$; and total suspended solids, 8.1-6.1 mg $L^{-1}$. The concentration of total nitrogen and total phosphorus decreased significantly (P<0.05) with a 26 ${\mu}m$ and 200 ${\mu}m$ filter pore size, respectively. Nutrients from dissolved organic substances were much higher than from particulates. Analysis of particle size fractionation and its effects on water quality is useful to estimate removal efficiencies of a commercial effluent screening device for solid management and development of solid removal systems.