여과-투과에 대한 실험적 분석: 여과매체의 종류, 여과매체의 매수, 여과압력의 영향

임성삼 ( Sung Sam Yim ),송연민 ( Yun Min Song ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.2

The average specific cake resistance, the most important indicator for cake filtration and solid-liquid separation, is measured by filtration experiment. But the exact value is difficult to measure because of the other influences such as sedimentation during filtration. This study, a little more stable method named filtration-permeation is proposed for measuring average specific cake resistance. The filtration-permeation is composed of permeation of particle eliminated water through pre-formed cake by filtration. Using 1 wt% calcium carbonate suspension, the filtration-permeation experiments were performed for 8 kinds of filter media at the conditions of 0.5 atm and 0.2 atm, 1 and 3 sheets of filter media, At each specific condition, three to five times filtration-permeation were accomplished. As a result, stable permeation speed is measured. According to this experimental result, the characteristics of permeation and the effect of sedimentation are analyzed with Ruth`s equation. The one way analysis of variance (one way ANOVA) is applied to the average specific cake resistances of filtration and permeation obtained with the selected three kinds of filter media. The average specific cake resistances between 0.5 atm and 0.2 atm by filtration do not distinguished, but those by permeation is perfectly distinguished. The experimental results during permeation have a very narrow distribution than that measured during filtration. The analysis of filtration experiments, it was verified that the resistance of filter medium by traditional method is of no significance. Finally, the migration of small particles through the medium composed of fiber glass at low pressure was studied.

모래층의 깊이에 따른 수직 및 수평적 완속여과의 처리효율에 관한 실험적 연구

金憫浩,李弘根 서울大學校保建大學院 1993 國民保健硏究所硏究論叢 Vol.3 No.1

The purpose od this study was to establish acceptable criteria for the design of the vertical slow sand filtration and the horizontal slow sand filtration as units in run area. The treatment efficiencies between vertical slow sand filtration and horizontal slow sand filtration under various conditions were investigated in this study. The main retsults of this study were as follows.. 1. There was no difference in the treatment efficiences or consumed KMnO₄, NH₃-N, NO₃-N, coliform and bacteria between vertical and horizontal filtration. 2. There was no difference in the treatment efficiences or consumed KMnO₄, NH₃-N, NO₃-N, turbidity, coliform and bacteria between vertical and horizontal filtrations with additional chlorination. 3. The treatment efficiencies were inproved in the vertical and horizontal filtrations when chlorination was added. 4. In the vertical and horizontal filtrations with additions, chlorination, the treatment efficiency reduced by depth of sand layer in order of 80cm, 60cm, 45cm. Accordingly, the depth of sand layer must be at least 60cm in simple piped water system. 5. Operating filtration for a long time, the horizontal filtration was more economical than the vertical filtration. When backwashing was operated to remove clogging accumlated on the sand layer, the decline of filtration rate could be prevented . Also, operation can be became for a longer time without sand washing.

Comparison of Efficiency between Pre-storage and Post-storage filtration by Leukoreduction Blood Filter

Geon Sik Shin,Bohee Kim,Sung Hoon Kim,Ki-Jong Rhee,Yoon Suk Kim 대한의생명과학회 2017 Biomedical Science Letters Vol.23 No.2

Leukocytes in blood components are involved in diverse adverse transfusion reactions such as febrile non-hemolytic transfusion reactions. Therefore, leukocyte reduction is required to reduce these adverse reactions. The objective of this study was to compare the efficiency of pre-storage filtration and post-storage filtration. Filtration time, residual leukocyte count, RBC recovery, and hemolysis were assessed after pre-storage or post-storage filtration. Compared to pre-storage filtration, filtration time was prolonged and hemolysis was dramatically increased when post-storage filtration was performed. Residual leukocytes count and RBC recovery after post-storage filtration were similar with those obtained after pre-storage filtration. These results suggest that pre-storage filtration has better efficiency than post-storage filtration. These are thought to contribute to the production of better quality of leukoreduction blood components.

여과-투과 방법의 이론적, 실험적 응용에 대한 연구

송연민(Yun Min Song),임성삼(Sung Sam Yim) 大韓環境工學會 2008 대한환경공학회지 Vol.30 No.2

본 연구에서는 새로운 여과-투과(filtration-permeation) 실험 방법을 사용하여 여과실험에 영향을 미치는 인자 중 침전에 대한 영향을 입자현탁액과 플럭현탁액에 대해 각각 수행하였다. 그 결과 여과실험으로는 정확한 평균 비저항값을 예측할 수 없었으나, 투과실험으로 정확한 평균 비저항값을 측정할 수 있었다. 투과기간을 연장하였을 때 입자현탁액에서 형성된 케이크에서는 투과속도에 별다른 영향이 없었으나 플럭현탁액의 경우는 응집제의 쓸려나감 현상을 보였다. 또한 여과-투과 실험을 사용하여 투과시에 단계적으로 압력을 증가시킴으로써 단 한번의 실험에 의해 케이크의 압축성이 측정되어 질 수 있음을 보였으며, 이 방법을 응용하여 평균 비저항값이 큰 활성슬러지의 긴 여과시간을 짧게 줄여 측정하는 새로운 방법을 제안하였다. Using an experimental method named filtration-permeation, the influence of sedimentation during filtration was studied for the suspensions composed of particles and that of flocs. The average specific cake resistances measured by filtration do not give accurate values because of the sedimentations during filtration, but the permeation data give quite accurate values. The prolonged permeation rates for the cake formed from particulate suspension do not change, but that rate from the floc filtration changes by the sweeping of flocculant. It is proposed that the cake compressibility can be measured with one set of filtration-permeation experiment by step increase of pressure during permeation period. The another experimental method which can shorten experimental time for floc filtration using filtration- permeation is also proposed.

Filtration-induced pressure evolution in permeation grouting

Zilong Zhou,Haizhi Zang,Shanyong Wang,Xin Cai,Xueming Du 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.75 No.5

Permeation grouting is of great significance for consolidating geo-materials without disturbing the original geo-structure. To dip into the filtration-induced pressure increment that dominates the grout penetration in permeation grouting, nonlinear filtration coefficients embedded in a convection-filtration model were proposed, in which the volume of cement particles in grout and the deposited particles of skeleton were considered. An experiment was designed to determine the filtration coefficients and verify the model. The filtration coefficients deduced from experimental data were used in simulation, and the modelling results matched well with the experimental ones. The pressure drop revealed in experiments and captured in modelling demonstrated that the surge of inflow pressure lagged behind the stoppage of flow channels. In addition, both the consideration of the particles loss in liquid grout and the number of filtrated particles on pore walls presented an ideal trend in filtration rate, in which the filtration rate first rose rapidly and then reached to a steady plateau. Finally, this observed pressure drop was extended to the grouting design which alters the water to cement (W/C) ratio so as to alleviate the filtration effect. This study offers a novel insight into the filtration behaviour and has a practical meaning to extend penetration distance.

침전이 수반되는 케이크 여과 II: 새로운 분석과 케이크에 도입되는 현탁액의 고체 질량분율

임성삼 ( Sung Sam Yim ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.3

Filtration on horizontal filter medium facing upward is accompanied by sedimentation. When sedimentation phenomenon is not considered, the average specific cake resistance by filtration could be in error more than two times. In the previous paper on this subject, it was insisted that the solid mass fraction of suspension changes in filtration period by sedimentation. But we could not find out the degree of change. At the first half of this paper, the average specific cake resistance measured by permeation will be proved to be exact in several means. The average specific cake resistance conventionally measured by filtration does not give correct results because it uses initial solid mass fraction of suspension. Then we calculated the changed solid mass fraction of suspension due to sedimentation during filtration by the experimental values obtained filtration-permeation method. We also determined the solid mass fraction at a certain moment of filtration from the suspension height and a new equation derived in this study. The two results were compared and proven that they almost matched.

Articles : Approach From Physicochemical Aspects in Membrane Filtration

( Eiji Iritani ),( Yasuhito Mukai ) 한국화학공학회 1997 Korean Journal of Chemical Engineering Vol.14 No.5

In membrane filtration, solution environment factors such as pH and solvent density are important in controlling the filtration rate and the rejection of the particles and/or the macromolecules. The filtration rate and the rejection in membrane filtration have been investigated from physicochemical aspects. It was shown that the properties of the filter cake formed on the membrane surface play a vital role in determining the filtration rate in membrane filtration. It was clearly demonstrated that such filtration behaviors as the filtration rate and the rejection are highly dependent on the electrical nature of the particles and/or the macromolecules. Furthermore, it was shown that the solvent density ρ has a large effect on the steady filtration rate in upward ultrafiltration.

Experience with Bank Filtration for the Public Water Supply in Dusseldorf, Germany

Schubert, Jurgen 嶺南大學校 環境問題硏究所 1997 環境硏究 Vol.16 No.2

The D?sseldorf Waterworks has been using bank filtration since 1870 as a means of water catchment. A great deal of experience and knowledge has been acquired over a period of more than 125 years. For the first 80 years, bank filtration alone, without additional treatment, sufficed in order to obtain safe potable water. After World WarⅡ, the quality of the Rhine water began to deteriorate. A few years later, the affects of this also became evident in the raw water in the wells near the river, making it necessary to treat the water for drinking purposes. Based on intensive studies, the ”D?sseldorf Treatment Process“, in which ozone and GAC are employed, was developed, and implemented for the first time at the D?sseldorf ”Am Staad“Waterworks. The first thermal reactivation plant of its kind, with a two-stage fluidized-bed reactor, was installed near the D?sseldorf ”Holthausen“Waterworks to recycle the used activated carbon. The positive trend in the quality of the water from the Rhine and its tributaries since 1970, reflects the success of national and international pollution control measures in the catchment area. The international Rhine Action Program, adopted a year after the Sandoz accident in 1986, gave effective impetus to the further improvement of the Rhine's ecosystem. Flow and transport phenomena occurring between the river and the wells the subject of a ”bank filtration“ research project which was successfully concluded a few years ago. One of the results of this project is a three-dimensional, dynamic simulation model, which describes the effect of shock loads resulting from accidental pollution of the river on the raw water in the wells. Another result is a tailor-made monitoring system, which has proven invaluable in determining and reporting any pollution of the Rhine due to accidents. The paper will essentially focus on water catchment by means of bank filtration embedded in the dynamic environment of a large river, including its scientific and technical background.

접촉여과방식 거친여과지에서 혼화조건과 여과속도가 고탁도 제거에 미치는 영향

박노백 ( Noh Back Park ),박상민 ( Sang Min Park ),홍진아 ( Jin Ah Hong ),전항배 ( Hang Bae Jun ) 대한상하수도학회 2007 상하수도학회지 Vol.21 No.3

Slow sand filtrations have been widely used for water treatment in small communities, however their capacity is often limited by high turbidity in the raw water. For this reason, several pre-treatment facilities were required for a slow sand filter. Turbidity removal from the highly turbid raw water was investigated in roughing filters as a pre-treatment process. The roughing filters followed by rapid mixing tank were operated in the form of a contact filtration. In several jar tests, the predetermined optimum aluminium sulfate (alum) doses for turbid water of 30 and 120NTU were 30 and 50mg/L, respectively. At the optimum alum dose, physically optimum parameters including G value of 220sec-1 and rapid mixing time of 3 minutes were applied to the contact filtration system. Without addition of alum, the filtrate turbidity from the roughing filters, packed respectively with different media such as sand, porous diatomite ball and gravel, was in the range of 5~30NTU at filtration velocities of 30 and 50m/day. However, the application of a contact filtration to roughing filters showed stably lower filtrate turbidity below 1.0NTU at filtration velocity of 30 m/day. Although the filtration velocity increased to 50m/day, filtrate turbidity was still below 1.0NTU in both single and double layer roughing filters. At influent turbidity of 120NTU, the filtrate turbidity was over 5 NTU in the triple layer roughing filter, which shortened the filter run time. The flocs larger than 10㎛, formed in the rapid mixing tank, were almost captured through the roughing filter bed, while the almost flocs smaller than 10㎛remained in filtrate.

고도정수처리에서 사여과와 정밀여과의 유기물처리특성에 관한 연구

김형석,이병호 대한상하수도학회 2010 상하수도학회지 Vol.24 No.6

With a belief of high water quality production and less chemical usage, membrane technology including Microfiltration (MF), Ultrafiltration (UF), and Nanofiltration(NF) is being employed more and more in drinking water treatment process. However, due to higher energy consumption of UF and NF, MF is normally used for drinking water treatment especially in a plant of large scale. In this investigation, performance ofsand filtration and membrane filtration was compared regarding removal of various water quality parameters, such as TOC, DOC, KMnO4 consumption, THMFP, and HAAFP. Two lines of pilot plant have been operated, one of which line is a traditional advanced water treatment process which includes sedimentation, sand filtration, ozonation, and activated carbon, and the other line is an alternative treatment process which includes sedimentation with inclined plate, MF membrane, ozonation, and activated carbon. For the first about 4months of period, MF filtration showed similar or little bit higher performance than sand filtration. However, after about 4month later, sand filtration showed much higher performance in removing all parameters monitored in the investigation. It was found that sand filtration is a better option than MF filtration as far as microbial community is fully activated in sand filter bed.