Filtration of surfactant-stabilized oil-in-water emulsions with porous ceramic membranes: Effects of membrane pore size and surface charge on fouling behavior

The membrane bioreactor (MBR), a combination of activated sludge process and the membrane separation system, has been widely used in wastewater treatment. However, 90% of MBR reported were employing polymeric membranes. The usage of ceramic membranes in MBR is quite rare. Four submerged ceramic membrane bioreactors (SCMBRs) with different membrane pore size were used in this study to treat sewage. The results showed that the desirable carbonaceous removal of 95% and ammonia nitrogen removal of 98% were obtained for all the SCMBRs. It was also showed that the ceramic membranes were able to reject some portions of the protein and carbohydrate, whereby the carbohydrate rejection rate was much higher than that of protein. Membrane pore size did not significantly affect the COD and TOC removal efficiencies, the composition of EPS and SMP or the membrane rejection rate, although slight differences were observed. The SCMBR with the biggest membrane pore size fouled fastest, and membrane pore size was a main contributor for the different fouling potential observed.

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Microfiltration of distillery stillage: Influence of membrane pore size

Acta periodica technologica ◽

10.2298/apt1243217v ◽

2012 ◽

pp. 217-224 ◽

Cited By ~ 1

Author(s):

Vesna Vasic ◽

Marina Sciban ◽

Aleksandar Jokic ◽

Jelena Prodanovic ◽

Dragana Kukic

Keyword(s):

Pore Size ◽

Food Industry ◽

Suspended Solids ◽

Oxygen Demand ◽

Ceramic Membranes ◽

Permeate Flux ◽

Filtration Process ◽

Waste Products ◽

Membrane Pore ◽

Membrane Pore Size

Stillage is one of the most polluted waste products of the food industry. Beside large volume, the stillage contains high amount of suspended solids, high values of chemical oxygen demand and biological oxygen demand, so it should not be discharged in the nature before previous purification. In this work, three ceramic membranes for microfiltration with different pore sizes were tested for stillage purification in order to find the most suitable membrane for the filtration process. Ceramic membranes with a nominal pore size of 200 nm, 450 nm and 800 nm were used for filtration. The influence of pore size on permeate flux and removal efficiency was investigated. A membrane with the pore size of 200 nm showed the best filtration performance so it was chosen for the microfiltration process.

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Impact of Membrane Pore Size on the Clarification Performance of Grape Marc Extract by Microfiltration

Membranes ◽

10.3390/membranes9110146 ◽

2019 ◽

Vol 9 (11) ◽

pp. 146 ◽

Cited By ~ 3

Author(s):

Mora ◽

Pérez ◽

Quezada ◽

Herrera ◽

Cassano ◽

...

Keyword(s):

Pore Size ◽

Ceramic Membranes ◽

Operating Conditions ◽

Operating Pressure ◽

Permeate Flux ◽

Membrane Pore ◽

Grape Marc ◽

Fouling Mechanism ◽

Pore Blocking ◽

Membrane Pore Size

The influence of membrane pore size on the permeate flux, fouling mechanism, and rejection of soluble and suspended solids, as well as of phenolics and anthocyanins, in the clarification of grape marc extract by microfiltration (MF) was studied. MF was operated by using three monotubular ceramic membranes with a pore size of 0.14, 0.2, and 0.8 µm, respectively, according to a batch concentration configuration in selected operating conditions (2.25 bar as operating pressure, 4.93 L/min as feed flow rate, and 25 °C as operating temperature). No significant differences in the permeate flux values were appreciated despite the difference in pore size. The mathematical analyses of the flux behavior revealed that intermediate pore blocking is the predominant mechanism for 0.14 and 0.2 µm membranes, whereas complete pore blocking prevails for the 0.8 µm membrane. Differences in the fouling mechanism were associated with differences in the total phenols rejection: the highest rejection was observed for the 0.8 µm membrane followed by 0.2 and 0.14 µm membranes. All selected membranes showed low rejection of sugars, with values lower than 10%, and no retention towards anthocyanins. All the clarified extracts showed a turbidity lower than 4.87 NTU. Based on the experimental results, the 0.14 µm membrane appeared as the best option for the clarification of grape marc extract.

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