Plasma fractionation by dead-end membrane filtration: Effects of membrane properties and plasma flux1

The manner in which membrane-fouling experiments are conducted and how fouling performance data are represented have a strong impact on both how the data are interpreted and on the conclusions that may be drawn. We provide a couple of examples to prove that it is possible to obtain misleading conclusions from commonly used representations of fouling data. Although the illustrative example revolves around dead-end ultrafiltration, the underlying principles are applicable to a wider range of membrane processes. When choosing the experimental conditions and how to represent fouling data, there are three main factors that should be considered: (I) the foulant mass is principally related to the filtered volume; (II) the filtration flux can exacerbate fouling effects (e.g., concentration polarization and cake compression); and (III) the practice of normalization, as in dividing by an initial value, disregards the difference in driving force and divides the fouling effect by different numbers. Thus, a bias may occur that favors the experimental condition with the lower filtration flux and the less-permeable membrane. It is recommended to: (I) avoid relative fouling performance indicators, such as relative flux decline (J/J0); (II) use resistance vs. specific volume; and (III) use flux-controlled experiments for fouling performance evaluation.

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Membrane filtration of wastewater effluents for reuse: effluent organic matter rejection and fouling

Water Science & Technology ◽

10.2166/wst.2001.0627 ◽

2001 ◽

Vol 43 (10) ◽

pp. 225-232 ◽

Cited By ~ 38

Author(s):

C. Jarusutthirak ◽

G. Amy

Keyword(s):

Organic Matter ◽

Membrane Filtration ◽

Treated Wastewater ◽

High Concentration ◽

Effluent Organic Matter ◽

Dead End ◽

Flux Decline ◽

Uf Membranes ◽

Stirred Cell ◽

Filtration Unit

The reuse of treated wastewater to augment natural drinking water supplies is receiving serious consideration. Treatment of secondary and tertiary effluent by membrane filtration was investigated by assessing nanofiltration (NF) membrane and ultrafiltration (UF) membranes in bench-scale experiments. It was found that secondary and tertiary effluent contained high concentration of effluent organic matter (EfOM), contributing EfOM-related fouling. Flux decline and EfOM rejection tests were evaluated, using a dead-end stirred cell filtration unit. Surface charge and molecular weight cut-off (MWCO) of membranes were significant factors in membrane performance including permeability and EfOM-rejection.

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Influence of operation conditions on cake structure in dead-end membrane filtration: Monte Carlo simulations and a force model

Chemical Engineering Research and Design ◽

10.1016/j.cherd.2017.06.008 ◽

2017 ◽

Vol 124 ◽

pp. 124-133 ◽

Cited By ~ 3

Author(s):

Kang Guan ◽

Yang Liu ◽

Xiaoqin Yin ◽

Weiya Zhu ◽

Yanhui Chu ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Membrane Filtration ◽

Force Model ◽

Operation Conditions ◽

Dead End

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Research experiences in direct potable water treatment using coagulation/ultrafiltration

Water Science & Technology ◽

10.2166/wst.2005.0641 ◽

2005 ◽

Vol 51 (6-7) ◽

pp. 221-229 ◽

Cited By ~ 9

Author(s):

A. Lerch ◽

S. Panglisch ◽

R. Gimbel

Keyword(s):

Membrane Filtration ◽

Potable Water ◽

Research Experiences ◽

Dead End ◽

New Concepts ◽

Capillary Membranes ◽

Pre Treatment ◽

High Flexibility ◽

Theoretical Considerations ◽

Potable Water Treatment

Recently, new concepts for direct or pre-treatment minimised processes for the treatment of surface waters to potable water have aroused more and more interest. The requirements of such concepts are various and express the desire for high flexibility, adaptation on various water qualities and expandability of the treatment process. These requirements can be nearly ideally achieved by membrane technology. This publication presents the actual approach in research, piloting and operation of selective plants, research institutions and universities for the hybrid process coagulation/ultrafiltration (UF), or microfiltration (MF) respectively. The focus is set on the discussion of the influences of the mass freight, coagulation conditions, temperature and theoretical considerations about the coating layer build-up in dead-end and IN/OUT-mode driven MF and UF capillary membranes with a coagulation step prior to membrane filtration.

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Mekanisme Fouling pada Membran Mikrofiltrasi Mode Aliran Searah dan Silang

Jurnal Rekayasa Proses ◽

10.22146/jrekpros.40458 ◽

2019 ◽

Vol 13 (1) ◽

pp. 6 ◽

Cited By ~ 1

Author(s):

Iqbal Shalahuddin ◽

Yusuf Wibisono

Keyword(s):

Membrane Filtration ◽

Cross Flow ◽

Flow Mode ◽

Cake Filtration ◽

Water And Wastewater Treatment ◽

Critical Flux ◽

Membrane Pores ◽

Fouling Mechanism ◽

Dead End ◽

Microfiltration Membranes

A B S T R A C TMicrofiltration is a low pressure driven membrane process of about 1 bar trans-membrane pressure which is used frequently for separating dissolved particles within 0.1 to 10 μm size. Microfiltration membranes are utilized in water and wastewater treatment processes either during pretreatment, treatment, or post-treatment steps. Moreover in bioprocessing, microfiltration is used in upstream process for substrate sterilization or in downstream process for microbial suspension separation. Fouling is one major concern of membrane filtration processes, including microfiltration. In this article, the fouling mechanism on microfiltration membrane is explained based on the blocking model refer to cake filtration due to the complexity of fouling phenomena. Fouling mechanism on dead-end and cross-flow modes microfiltration are explained, and basically distinguished into four different mechanisms, i.e. complete blocking, standard blocking, intermediate blocking and cake filtration. The proposed models are based on constant pressure operation on the uniform membrane pores, both for dead-end and cross-flow modes. Cross-flow mode, however, is restricted on the beginning of filtration until critical flux condition is reached.Keywords: bioprocess; blocking model; cake filtration; fouling; microfiltration; wastewater A B S T R A KMembran mikrofiltrasi merupakan salah satu teknologi membran yang menggunakan tekanan rendah sekitar 1 bar sebagai gaya pendorong dan digunakan untuk proses pemisahan partikel terlarut yang berukuran antara 0,1 hingga 10 μm. Membran mikrofiltrasi banyak digunakan baik dalam proses pra-pengolahan, pengolahan, maupun pasca-pengolahan air dan air limbah. Pada bioproses, mikrofitrasi juga digunakan pada proses hulu untuk sterilisasi substrat atau pada proses hilir untuk pemisahan suspensi mikrob. Masalah yang paling utama dalam proses filtrasi membran adalah fouling. Dalam artikel ini, mekanisme terjadinya fouling pada membran mikrofiltrasi dijelaskan dengan menggunakan model pemblokiran yang mengacu pada filtrasi deposit partikel (cake) untuk menguraikan kerumitan fenomena fouling dalam mikrofiltrasi. Pada tulisan ini dijelaskan lebih rinci mengenai mekanisme fouling baik pada mikrofiltrasi searah (dead-end) maupun aliran silang (cross-flow). Mekanisme fouling pada proses mikrofiltrasi bisa dimodelkan dengan empat model yaitu pemblokiran pori, penyempitan pori, pemblokiran pori bersamaan dengan endapan permukaan dan formasi endapan permukaan. Mekanisme tersebut berlaku pada kondisi operasional bertekanan tetap dan ukuran pori yang seragam, baik pada aliran searah ataupun silang. Hanya saja, model mekanisme pada aliran silang hanya berlaku pada kondisi awal filtrasi hingga tercapai kondisi fluks kritis.Kata kunci: air limbah; bioproses; filtrasi cake; fouling; mikrofiltrasi; model pemblokiran

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Effects of Particles Diffusion on Membrane Filters Performance

Fluids ◽

10.3390/fluids5030121 ◽

2020 ◽

Vol 5 (3) ◽

pp. 121

Author(s):

Shi Yue Liu ◽

Zhengyi Chen ◽

Pejman Sanaei

Keyword(s):

Pore Structure ◽

Flow Rate ◽

Membrane Filtration ◽

Membrane Filter ◽

Membrane Properties ◽

Filtration Process ◽

Membrane Pore ◽

Filtration Performance ◽

Structure Flow ◽

Slow Filtration

Membrane filtration fouling is a very complex process and is determined by many properties such as the membrane internal morphology, membrane pore structure, flow rate and contaminant properties. In a very slow filtration process or during the late stage of filtration, when the flow rate is naturally low and Péclet number is small, particle diffusion is essential and cannot be neglected, while in typical filtration models, especially in moderate and fast filtration process, the main contribution stems from the particle advection. The objectives of this study is to formulate mathematical models that can (i) investigate how filtration process varies under possible effects of particles diffusion; and (ii) describe how membrane morphology evolves and investigate the filtration performance during the filtration process. We also compare the results with the case that diffusion is less important and make a prediction about what kind of membrane filter pore structure should be employed to achieve a particular optimum filtration performance. According to our results, the filtrate and efficiency of particle separation are found to be under the trade-off relationship, and the selection of the membrane properties depends on the requirement of the filtration.

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Experimental Study of Fouling Behavior of Main Substances (BSA, HA, SA) of Dissolved Organic Matter (DOM) in Dead-end Membrane Filtration

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/301/1/012031 ◽

2018 ◽

Vol 301 ◽

pp. 012031 ◽

Cited By ~ 1

Author(s):

Yongjun Sun ◽

Kexin Zhu ◽

Bushra Khan ◽

Xinpei Du ◽

Lei Hou ◽

...

Keyword(s):

Experimental Study ◽

Organic Matter ◽

Dissolved Organic Matter ◽

Membrane Filtration ◽

Dead End

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Modeling NOM fouling of low pressure membranes: impact of membrane properties and NOM characteristics

Water Science & Technology Water Supply ◽

10.2166/ws.2008.003 ◽

2008 ◽

Vol 8 (1) ◽

pp. 75-83

Author(s):

NoHwa Lee ◽

John Pellegrino ◽

Gary Amy

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Principal Component ◽

Low Pressure ◽

Time Frame ◽

Membrane Properties ◽

Flux Decline ◽

Cake Layer ◽

Highly Correlated ◽

Significant Flux

This research attempted to identify characteristic coordinates responsible for significant flux decline in low pressure membrane filtration, and to explain relationships among those coordinates with a modeling approach. A Pearson's correlation matrix supported that significant flux decline over a short time frame (low delivered DOC) is highly correlated with high molecular weight (MW) components of NOM. Simulations of flux decline by model equations were close to the experimental results revealing that low pressure membrane fouling is dominantly affected by NOM characteristics and membrane properties. One source water, exhibiting the highest flux decline, showed mostly cake formation as a fouling mechanism. The results indicate that significant flux decline is caused by high MW components leading to formation of a cake layer. Principal component analysis (PCA) revealed that high MW polysaccharides are the most important NOM component affecting significant membrane fouling.

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