scholarly journals The Effect of Ca and Mg Ions on the Filtration Profile of Sodium Alginate Solution in a Polyethersulfone-2-(methacryloyloxy) Ethyl Phosphorylchloline Membrane

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1207 ◽  
Author(s):  
Nasrul Arahman ◽  
Suffriandy Satria ◽  
Fachrul Razi ◽  
M. Bilad
Keyword(s):  
Sodium Alginate ◽  
Relative Permeability ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Hollow Fiber Membrane ◽  
Pure Water ◽  
Fiber Membrane ◽  
Cake Layer ◽  
The Stability

The efforts to improve the stability of membrane filtration in applications for wastewater treatment or the purification of drinking water still dominate the research in the field of membrane technology. Various factors that cause membrane fouling have been explored to find the solution for improving the stability of the filtration and prolong membrane lifetime. The present work explains the filtration performance of a hollow fiber membrane that is fabricated from polyethersulfone-2-(methacryloyloxy) ethyl phosphorylchloline while using a sodium alginate (SA) feed solution. The filtration process is designed in a pressure driven cross-flow module using a single piece hollow fiber membrane in a flow of outside-inside We investigate the effect of Ca and Mg ions in SA solution on the relative permeability, membrane resistance, cake resistance, and cake formation on the membrane surface. Furthermore, the performance of membrane filtration is predicted while using mathematical models that were developed based on Darcy’s law. Results show that the presence of Ca ions in SA solution has the most prominent effect on the formation of a cake layer. The formed cake layer has a significant effect in lowering relative permeability. The developed models have a good fit with the experimental data for pure water filtration with R2 values between 0.9200 and 0.9999. When treating SA solutions, the developed models fit well with experimental with the best model (Model I) shows R2 of 0.9998, 0.9999, and 0.9994 for SA, SA + Ca, and SA + Mg feeds, respectively.

Fouling in hollow fiber membrane microfilters used for household water treatment

2015 ◽  
Vol 5 (2) ◽  
pp. 220-228 ◽  
Author(s):  
Anna Murray ◽  
Mario Goeb ◽  
Barbara Stewart ◽  
Catherine Hopper ◽  
Jamin Peck ◽  
...  
Keyword(s):  
Water Treatment ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Hollow Fiber Membrane ◽  
Sterile Water ◽  
Fiber Membrane ◽  
Chemical Cleaning ◽  
Household Water Treatment ◽  
Household Water

The Sawyer PointOne hollow fiber membrane microfilter is promoted for household water treatment in developing countries. Critical limitations of membrane filtration are reversible and irreversible membrane fouling, managed by backwashing and chemical cleaning, respectively. The PointOne advertised lifespan is 10 years; users are instructed to backwash as maintenance. Owing to reduced turbidity and bacterial removal efficiencies, six PointOnes were removed from Honduran homes after 23 months of use. In the laboratory, we tested sterile water filtrate for turbidity and bacterial presence before and after backwashing and chemical cleaning. Sterile water filtrate from uncleaned filters had turbidity of 144–200 NTU and bacteria counts of 13–200 CFU. Cleaned filter effluent was positive for total coliforms. On one new and one used, cleaned filter, we imaged membranes with scanning electron microscopy and characterized surface elemental compositions with spectroscopy. Images and spectroscopy of the used, cleaned membrane revealed a dense, cake fouling layer consisting of inorganic metal oxides, organic material, and biofouling. Burst fibers were visually observed. This PointOne was thus irreversibly fouled and non-functional after <2 years of use. Further research is recommended to determine: impacts of source water quality on PointOne performance, a cleaning regimen to manage fouling, and an appropriate filter lifespan.

scholarly journals Optimization of In Situ Backwashing Frequency for Stable Operation of Anaerobic Ceramic Membrane Bioreactor

Processes ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 545 ◽  
Author(s):  
Rathmalgodage Thejani Nilusha ◽  
Tuo Wang ◽  
Hongyan Wang ◽  
Dawei Yu ◽  
Junya Zhang ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Membrane Filtration ◽  
Membrane Bioreactor ◽  
Ceramic Membrane ◽  
Pure Water ◽  
Ex Situ ◽  
Stable Operation ◽  
Chemical Cleaning ◽  
Cake Layer

The cost-effective and stable operation of an anaerobic ceramic membrane bioreactor (AnCMBR) depends on operational strategies to minimize membrane fouling. A novel strategy for backwashing, filtration and relaxation was optimized for stable operation of a side stream tubular AnCMBR treating domestic wastewater at the ambient temperature. Two in situ backwashing schemes (once a day at 60 s/day, and twice a day at 60 s × 2/day) maintaining 55 min filtration and 5 min relaxation as a constant were compared. A flux level over 70% of the initial membrane flux was stabilized by in situ permeate backwashing irrespective of its frequency. The in situ backwashing by permeate once a day was better for energy saving, stable membrane filtration and less permeate consumption. Ex situ chemical cleaning after 60 days’ operation was carried out using pure water, sodium hypochlorite (NaOCl), and citric acid as the order. The dominant cake layer was effectively reduced by in situ backwashing, and the major organic foulants were fulvic acid-like substances and humic acid-like substances. Proteobacteria, Firmucutes, Epsilonbacteria and Bacteroides were the major microbes attached to the ceramic membrane fouling layer which were effectively removed by NaOCl.

Structure Morphology of Polyethersulfone Hollow Fiber Membrane via Immersion Precipitation Phase Inversion Process

2012 ◽  
Vol 152-154 ◽  
pp. 574-578 ◽  
Author(s):  
Ping Lan ◽  
Wei Wang
Keyword(s):  
Hollow Fiber ◽  
Phase Inversion ◽  
Hollow Fiber Membrane ◽  
Pure Water ◽  
Water Flux ◽  
Additive Concentration ◽  
Hollow Fiber Membranes ◽  
Fiber Membrane ◽  
Fiber Membranes ◽  
And Performance

Polyethersulfone (PES) hollow fiber membranes have been widely used in many fields, such as ultrafiltration, microfiltration, reverse osmosis, liquid/liquid or liquid/solid separation, gas separation, hemodialysis, and so on. In this paper, the sheet PES hollow fiber membranes were prepared. The morphology and performance of membranes can be controlled. By studying the influence of the compositions and conditions on the morphology and performance of PES hollow fiber membrane, the relationship of morphology and performance of the membrane is acquired. The additives were used such as glycerol, BuOH and PEG. In addition, immerse phase inversion was used as membranes preparation method. The morphology of the membrane was controlled by changing kinds of additive, concentration of additive and so on. It was found that the membrane morphologies were changed by additive obviously. Porosity , pure water flux, scanning electron microscopy(SEM) were used to characterize the morphology and performance of the membranes.

Extraction and Purification of Tea Polyphenols and EGCG

2013 ◽  
Vol 662 ◽  
pp. 392-395 ◽  
Author(s):  
Yan Hua Gao ◽  
Ying Chen ◽  
Zhen Xi Wang
Keyword(s):  
Green Tea ◽  
Silica Gel ◽  
Hollow Fiber ◽  
Membrane Filtration ◽  
Hollow Fiber Membrane ◽  
Tea Polyphenols ◽  
Fiber Membrane ◽  
Extraction And Purification ◽  
Column Chromatographic

The extraction and purification of tea polyphenols(TP) and EGCG from green tea extraction by nano-membrane filtration, resins absorption and column chromatographic exctration(CCE) were studied. The results indicated that the concentrations of TP and EGCG respectively increased to 35.21% and 13.56% after separated by the hollow fiber membrane with the molecular of 1.0×104. And then, after the absorption of polyamide resins, the concentrations further increased to 95.51% and 52.56%. Finally, the product with the EGCG concentration of 98% was obtained by silica gel CCE method.

Performance and fouling characterization of a five-bore hollow fiber membrane in a membrane bioreactor for the treatment of printing and dyeing wastewater

2016 ◽  
Vol 87 (1) ◽  
pp. 102-109 ◽  
Author(s):  
Chunyan Ma ◽  
Xiaoqian Wu ◽  
Zhenhong Liu
Keyword(s):  
Hollow Fiber ◽  
Membrane Bioreactor ◽  
Hollow Fiber Membrane ◽  
Oxygen Demand ◽  
Dyeing Wastewater ◽  
Fiber Membrane ◽  
Step Method ◽  
Critical Flux ◽  
Printing And Dyeing Wastewater ◽  
Cake Layer

Filtration performance and fouling behavior of a five-bore hollow fiber membrane was investigated in a membrane bioreactor (MBR) treating printing and dyeing wastewater. A normal single-bore hollow fiber membrane module was used in the same bioreactor for comparison. During an operation over 30 days, the results of chemical oxygen demand (COD) and color removals demonstrated that the five-bore membrane was favorable for this wastewater treatment. The critical flux ( Jc) of the five-bore membrane and the single-bore membrane was determined at 21 and 15 L/(m2·h), respectively, using a flux-step method. During a steady running at sub-critical flux of 10 L/(m2·h) without cleaning for 50 days, the average increasing rates of trans-membrane pressure (TMP) for five-bore and single-bore membranes were 0.356 kPa/d and 0.444 kPa/d, respectively, indicating that the five-bore membrane had better fouling resistance. The total resistance values of five-bore membrane and single-bore membrane were 8.68 and 14.1 m−1, respectively. Scanning electron microscope (SEM) and atomic force microscope (AFM) results confirmed the cake layer resistance for five-bore membrane was much lower than single-bore membrane. It was expected that the membrane structure, especially the membrane diameter, influenced the anti-fouling property of five-bore membrane.

The Effects of Nanocrystaline Cellulose on Polysulfone Hollow-Fiber Ultrafiltration Membrane

2012 ◽  
Vol 528 ◽  
pp. 210-213 ◽  
Author(s):  
Xuan Wang ◽  
Hao Long Bai ◽  
Li Ping Zhang
Keyword(s):  
Hollow Fiber ◽  
Phase Inversion ◽  
Hollow Fiber Membrane ◽  
Pure Water ◽  
Water Flux ◽  
Ultrafiltration Membrane ◽  
Fiber Membrane ◽  
Elongation At Break ◽  
Pure Water Flux ◽  
Scaning Electron Microscopy

Nanocrystalline cellulose was used to blend with polysulfone to improve the hydrophicility and mechanical properties of PS hollow fiber ultrafiltration membrane. The method of dry-jet/wet-spining was adopted to form the hollow fiber by the mechanism of phase-inversion. In addition, the content of NCC was increased gradually from 0% to 1 wt% to examin the permeation flux, rejection ratio of bovine serum albumin(BSA) and mechanical strength of PS hollow-fiber. We find that the pure water flux was soared when NCC content was increased. The tensile strength and elongation at break were also detected and calculated. The results indicated that the properties of PS hollow-fiber membrane with appropriate NCC content were enhanced. The hollow fiber membranes were also observed with scaning electron microscopy(SEM) to explore the porous structure

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