• Journal of the Korean GEO-environmental Society
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• v.14 no.4
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• pp.15-27
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• 2013

In order to plan out the Daegu G membrane filtration water treatment plant, water quantity, water quality and process stability were evaluated using the field pilot-scale tests, during the six months of continuous operation, including low water temperature period. The field model experiments, which were carried out according to the Installation Criteria of Ministry of Environment, consisted of two series : series 1 - water quality verification, and series 2 - membrane process evaluation. The process water quality met all drinking water standards with less than 0.03 NTU. Moreover, process operation showed a stable membrane pressure with 99% of recovery ratio. This shows that the tests were properly designed in terms of the influence of water loading and temperature. In conclusion, the purpose of this study is to establish core technology for advanced drinking water treatment, through on-going accumulation of engineering and construction know-how.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.12-18
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• 1999

This research was undertaken to do the technical and economical feasibility study of membrane water treatment system. For the technical feasibility study, batch water treatment system using UF(ultrafiltration) was set up and several experiments were carried out. The performance of the UF membrane was tested in terms of turbidity. The experimental results showed that the UF membrane process produced less than 1 NTU water regardless of input water turbidity. For the economical feasibility study, the cost model was analyzed and programmed for simulation. Also costs of the membrane water treatment and the conventional treatment were evaluated. The simulation results showed that the unit production cost increased when design flow or permeate flow decreased. The production cost of membrane water treatment system was lower than that of the conventional system. Both technical and economical feasibility study showed that the UF membrane water purification system was a very competitive water purification process.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.327-327
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• 2021

하수재이용에서 전처리 막여과 공정은 완벽한 고액분리로 인해 후단 역삼투막 손상을 줄일 수 있는 공정으로 각광을 받고 있다. 일반적으로 막여과 공정은 여과->물리세정->충진->여과 와 같은 제막사에서 제공하는 운전 사이클에 맞춰 적용하고 있으며 유지세정 역시 1회/일 또는 1회/주 단위로 정해진 범위에서 수행되고 있다. 이러한 운전 방식은 시시각각 변화하는 막 유입수질에 적절하게 대응하지 못해 장기적으로 막오염 발생에 따른 생산수량 감소는 물론 막오염 제거를 위한 화학세정 주기가 짧아져 전체적인 생산수량이 감소하는 원인이 되고 있다. Raffine(2012)에 따르면 가역적 막오염의 경우 Flux 증가에 큰 영향이 없으나 비가역적 막오염은 Flux 증가에 따라 급격히 증가한다고 보고하고 있으며 이는 제한된 분리막 면적당 처리수 생산량을 증가시키기 위해 비가역적 막오염의 발생량을 줄이는 것이 필요하며 이를 위해 주기적인 강화역세(Chemical Enhanced Backwashing, CEB)가 도입되고 효율적인 유지세정 방법에 대한 연구가 진행되고 있다. 당사에서는 일산에 있는 I 수질복원센터내에 25 m³/일 규모의 막여과 하수재이용 파일롯 플랜트를 설치하고 막여과 하수재이용 공정의 운영 효율을 높이기 위하여 W사에서 개발한 IntelliFluxControl(IFCr) 소프트웨어를 이용하여 하수재이용 막여과 성능을 확인 하였다. IFCr은 실시간으로 변화하는 수질에 따른 막오염 정도에 따라 역세 강도 및 빈도와 CEB 적용 정도를 변화시켜 분리막 운전의 효율을 높일 수 있는 운영 소프트웨어이다. I 수질복원센터의 하수 방류수를 막여과 유입수로 적용하여 40 LMH를 기준으로 IFCr을 적용하지 않은 경우 23.7일 운전 가능하였으나 IFCr을 적용한 경우 50일 연속 운전이 가능하였다. 또한 역세척수를 운전 기간 동안 약 50 m³을 사용한 반면 IFCr을 적용한 경우 이에 절반 수준인 24.1 m³ 만 사용하여 회수율이 91%에서 95%로 증가한 것을 확인 할 수 있었다. 본 연구의 결과는 기존의 제막사에서 제시하는 막 공정 운영방법을 탈피하여 분리막이 갖고 있는 성능을 최대한 끌어 올릴 수 있는 연구 결과라고 판단되며 향후 스케일 업 연구를 통해 실제 플랜트에 적용 가능성이 확인 될 경우 시설의 설치 막모듈 개수와 유지관리비를 동시에 절감할 수 있는 기술이 될 수 있을 것이다

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.139-146
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• 2013

A process diagnosis method for membrane water treatment plant was developed using a constant flux membrane fouling model. This diagnosis method can be applied to a real-field membrane-based water treatment plant as an early alarming system for membrane fouling. The constant flux membrane fouling model was based on the simplest equation form to describe change in trans-membrane pressure (TMP) during the filtration cycle from a literature. The model was verified using a pilot-scale microfiltraton (MF) plant with two commercial MF membrane modules (72 m2 of membrane area). The predicted TMP data were produced using the model, where the modeling parameters were obtained by the least square method using the early plant data and modeling equations. The diagnosis was carried out by comparing the predicted TMP data (as baseline) and real plant data. As a result of the case study, the diagnsis method worked pretty well to predict the early points where fouling started to occur.

• Membrane Journal
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• v.17 no.3
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• pp.161-173
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• 2007

Membrane filtration processes are increasingly popular for drinking water treatment that requires high quality of water. Low pressure membrane(LPM) processes such as microfiltration(MF) and ultrafiltration(UF), however, are ineffective in the removal of dissolved organic matter and also membrane fouling is still an important issue to be resolved. High pressure membranes(HPMs) may guarantee better water quality, but at the high energy consumption. Thus, various approaches to combine LPM processes with other physicochemical methods have been recently made to achieve their efficiency to the level comparable to that of HPM processes. In this work, therefore, hybrid processes that coupled MF/UF with coagulation, adsorption, chemical reactions(e.g., chelation and oxidation) are reviewed regarding system design and performance and also membrane surface modifications conducted by grafting and polyelectrolyte multilayer formation were assessed.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.8
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• pp.837-843
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• 2005

Coagulation influence was evaluated as the pretreatment for ultrafiltration. Coagulation was expected to improve water quality, reduce membrane fouling and increase backwash effect. Continuous operation of UF was employed in order to investigate the influence of coagulation. Alum, PACS and Ferric chloride were used as coagulants separately. From the result of the research, coagulation can improve the treated water quality greatly. Organic removal was increased more than turbidity and showed an improvement of 30.6% at most. All three coagulants presented conspicuous reduction of membrane fouling, among which PACS was the most effective with long term run. Backwash effect differed with different coagulants while Ferric chloride turned out to be the most effective one. The optimum dosage of coagulant resulted in the highest backwash efficiency.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.05a
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• pp.17-28
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• 2003

• Membrane Journal
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• v.25 no.6
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• pp.503-514
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• 2015

In this study, water purification system without coagulant was consisted of F/A and membrane to produce purified water which only uses physical treatment without coagulant. Because the use of coagulant has a possibility remaining of hazardous aluminum with our health. Especially, the Filtralite was reviewed the possibility to remove turbidity and organic material. It was found that the turbidity removal rate of Filtralite was 83~84%. It show that Filtralite has similar efficiency to sand-filter. But Filtralite has higher 50% removal rate of organic material than sand-filter due to well-developed pore on the surface of it. So, Filtralite could be used to substitute the sand-filter for the F/A process due to higher removal rate. And also coupled with activated carbon in F/A process, TMP was increased by TOC value. To prevent increasing TMP, media that has outstanding organic adsorption ability should be used.

• Membrane Journal
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• v.23 no.1
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• pp.12-23
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• 2013

On the subject of river bed water in Seomjin river, it had accomplished the verifying experiment of membrane filtration pilot plant for evaluating the applicability of its process throughout the prediction of membrane fouling as a function of the pore size of membrane and the determination of optimum coagulant dosage. On the result of the experiment for the evaluation of the membrane fouling as a function of the pore size, a increasing rate of irreversible resistance of membrane pore size $0.1{\mu}m$ and $0.01{\mu}m$ was measured each $0.44{\times}10^{12}/m^2$ and $0.42{\times}10^{12}/m^2$, respectively. And on the result of Flux-test, it showed that the optimum coagulant dosage was measured lower than the it of the Jar-test. The result to be operated in a condition of a permeate flux $1.0{\sim}1.5m^3/m^2{\cdot}day$ without coagulation and a permeate flux $1.0{\sim}2.0m^3/m^2{\cdot}day$ with coagulation was maintained at stable trans-membrane pressure (TMP) value for 6 months up to. Therefore it showed that the stable operation without the coagulation was possible on permeate flux $1.0{\sim}1.5m^3/m^2{\cdot}day$ in the operation of membrane filtration process.

• Proceedings of the Membrane Society of Korea Conference
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• 2002.05a
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• pp.23-31
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• 2002

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