Exploring the feasibility of novel double-skinned forward osmosis membranes with higher flux and superior anti-fouling properties for sludge thickening

Forward osmosis (FO) is an emerging process for dewatering solid–liquid stream which has the potential to be innovative and sustainable. However, the applications have still been hindered by low water flux and membrane fouling when activated sludge is used as the feed solution due to bound water from microbial cells. Hence, a novel strategy was designed to increase sludge thickening and reduce membrane fouling in the FO process under ultrasonic condition. The results from the ultrasound/FO hybrid system showed that the sludge concentration reached up to 20,400 and 28,400 mg/L from initial sludge concentrations of 3000 and 8000 mg/L with frequency of 40 kHz after 22 hours, while the system without ultrasound had to spend 26 hours to achieve the same sludge concentration. This identifies that the presence of ultrasound strongly affected sludge structure as well as sludge thickening of the FO process. Furthermore, the ultrasound/FO hybrid system could achieve NH4+-N removal efficiency of 96%, PO43−-P of 98% and dissolved organic carbon (DOC) of 99%. The overall performance demonstrates that the proposed ultrasound/FO system using seawater as a draw solution is promising for sludge thickening application.

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Mitigation of membrane fouling in a seawater-driven forward osmosis system for waste activated sludge thickening

Journal of Cleaner Production ◽

10.1016/j.jclepro.2019.118373 ◽

2019 ◽

Vol 241 ◽

pp. 118373 ◽

Cited By ~ 5

Author(s):

Faqian Sun ◽

Dan Lu ◽

Jia Shin Ho ◽

Tzyy Haur Chong ◽

Yan Zhou

Keyword(s):

Activated Sludge ◽

Membrane Fouling ◽

Forward Osmosis ◽

Waste Activated Sludge ◽

Sludge Thickening

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Desalination performance of thin-film composite forward osmosis membranes based on different carbon nanomaterials

Egyptian Journal of Chemistry ◽

10.21608/ejchem.2020.27083.2646 ◽

2020 ◽

Vol 0 (0) ◽

pp. 0-0 ◽

Cited By ~ 1

Author(s):

Amira Shawky

Keyword(s):

Thin Film ◽

Carbon Nanomaterials ◽

Forward Osmosis ◽

Film Composite ◽

Thin Film Composite

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The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan

Water Science & Technology ◽

10.2166/wst.1986.0300 ◽

1986 ◽

Vol 18 (7-8) ◽

pp. 289-296

Author(s):

C. F. Ouyang ◽

T. J. Wan

Keyword(s):

Biological Treatment ◽

Wastewater Treatment Plants ◽

Oxygen Demand ◽

Field Investigation ◽

Oxidation Ditch ◽

Trickling Filter ◽

Rotating Biological Contactor ◽

Treatment Processes ◽

Treatment Characteristics ◽

Sludge Thickening

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan. The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater. Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.

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