Vacuum evaporation and reverse osmosis treatment of process wastewaters containing surfactant material: COD reduction and water reuse

We have demonstrated a novel backwash cleaning technique of direct osmosis (DO)-high salinity (HS) for reverse osmosis (RO) fouling control in water reuse. An UF-RO pilot system was continuously (24-h) operated on site with the secondary effluent as the feed over 4 months. The RO plant was run at 75% recovery and at the membrane flux of 17 l m−2 h−1 (LMH) to simulate the full scale NEWater production when DO-HS treatment was conducted once per day and five times per week during the last two months. Permeability of RO membranes as a function of elapse time of the pilot operation was monitored and compared over different durations. Impact of DO-HS treatment on RO product quality in terms of TOC and conductivity was investigated. It was concluded that the DO-HS treatment preliminarily demonstrated a benefit to low RO fouling rate by 2.5–4 times in 30–60 days without interruption on RO operation and impact on RO product quality.

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Recycling of Reverse Osmosis Concentrates to the Membrane Bioreactor in the MBR-RO Process for Water Reuse: effect on mbr performances

Revue des sciences de l eau ◽

10.7202/1040057ar ◽

2017 ◽

Vol 30 (1) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Thi Thu Nga Vu ◽

Manon Montaner ◽

Christelle Guigui

Keyword(s):

Organic Matter ◽

Reverse Osmosis ◽

Membrane Fouling ◽

Water Reuse ◽

High Performance ◽

Membrane Bioreactor ◽

Membrane System ◽

Size Exclusion ◽

Ro Concentrate ◽

The Impact

Wastewater effluents can be treated by an integrated membrane system combining membrane bioreactor (MBR) and reverse osmosis (RO) for effective removal of micropollutants in the field of high-quality water reuse. However, discharging the RO concentrate waste stream directly into the natural environment could lead to serious problems due to the toxic components contained in the concentrates (micropollutants, salts, organic matter). A possible solution could be the recirculation of RO concentrate waste to the MBR. However, such an operation should be studied in detail since the recirculation of non-biodegradable organic matter or high concentrations of salts and micropollutants could directly or indirectly contribute to MBR membrane fouling and modification of the biodegradation activity. In this context, the work reported here focused on the recirculation of such concentrates in an MBR, paying specific attention to MBR membrane fouling. Lab-scale experiments were performed on a continuous MBR-RO treatment line with RO concentrate recirculation. The main goal was to determine the recovery of the RO unit and of the global process that maintained good process performance in terms of biodegradation and MBR fouling. The results demonstrate that the impact of the toxic flow on activated sludge depends on the recovery of the RO step but the same trends were observed regardless of the organic matter and salt contents of the concentrates: the concentration of proteins increased slightly. Size-exclusion high performance liquid chromatography (HPLC-SEC) was employed to study the effects of RO concentrate on the production of protein-like soluble microbial products (SMPs) and demonstrated a significant peak of protein-like substances corresponding to 10-100 kDa and 100-1 000 kDa molecules in the supernatant. Thus a significant increase in the propensity for sludge fouling was observed, which could be attributed to the increased quantity of protein-like substances. Finally, the effect of the concentrate on sludge activity was studied and no significant effect was observed on biodegradation, indicating that the return of the concentrate to the MBR could be a good alternative.

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Boron as a Surrogate for N-Nitrosodimethylamine Rejection by Reverse Osmosis Membranes in Potable Water Reuse Applications

Environmental Science & Technology ◽

10.1021/es400732x ◽

2013 ◽

Vol 47 (12) ◽

pp. 6425-6430 ◽

Cited By ~ 11

Author(s):

Kha L. Tu ◽

Takahiro Fujioka ◽

Stuart J. Khan ◽

Yvan Poussade ◽

Annalie Roux ◽

...

Keyword(s):

Reverse Osmosis ◽

Water Reuse ◽

Potable Water ◽

Reverse Osmosis Membranes

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Forward osmosis for the treatment of reverse osmosis concentrate from water reclamation: process performance and fouling control

Water Science & Technology ◽

10.2166/wst.2014.138 ◽

2014 ◽

Vol 69 (12) ◽

pp. 2431-2437 ◽

Cited By ~ 19

Author(s):

C. Kazner ◽

S. Jamil ◽

S. Phuntsho ◽

H. K. Shon ◽

T. Wintgens ◽

...

Keyword(s):

Reverse Osmosis ◽

Water Reuse ◽

Membrane Filtration ◽

Inorganic Compounds ◽

Forward Osmosis ◽

Building Blocks ◽

Water Recovery ◽

Liquid Discharge ◽

Quality Water ◽

A Minor

While high quality water reuse based on dual membrane filtration (membrane filtration or ultrafiltration, followed by reverse osmosis) is expected to be progressively applied, treatment and sustainable management of the produced reverse osmosis concentrate (ROC) are still important issues. Forward osmosis (FO) is a promising technology for maximising water recovery and further dewatering ROC so that zero liquid discharge is produced. Elevated concentrations of organic and inorganic compounds may act as potential foulants of the concentrate desalting system, in that they consist of, for example, FO and a subsequent crystallizer. The present study investigated conditions under which the FO system can serve as concentration phase with the focus on its fouling propensity using model foulants and real ROC. Bulk organics from ROC consisted mainly of humic acids (HA) and building blocks since wastewater-derived biopolymers were retained by membrane filtration or ultrafiltration. Organic fouling of the FO system by ROC-derived bulk organics was low. HA was only adsorbed moderately at about 7% of the initial concentration, causing a minor flux decline of about 2–4%. However, scaling was a major impediment to this process if not properly controlled, for instance by pH adjustment or softening.

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Performance of nanofiltration and reverse osmosis after membrane bioreactor for urban source-separated urine treatment and water reuse

10.5004/dwt.2017.21441 ◽

2017 ◽

Vol 95 ◽

pp. 18-33 ◽

Cited By ~ 4

Author(s):

Mathias Monnot ◽

Bénédicte Nguyen ◽

François Zaviska ◽

Geoffroy Lesage ◽

Marc Héran

Keyword(s):

Reverse Osmosis ◽

Water Reuse ◽

Membrane Bioreactor ◽

Urine Treatment

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Preozonation Effects on the Reduction of Reverse Osmosis Membrane Fouling in Water Reuse

Ozone Science and Engineering ◽

10.1080/01919512.2011.607385 ◽

2011 ◽

Vol 33 (5) ◽

pp. 379-388 ◽

Cited By ~ 27

Author(s):

Benjamin D. Stanford ◽

Aleksey N. Pisarenko ◽

R. David Holbrook ◽

Shane A. Snyder

Keyword(s):

Reverse Osmosis ◽

Membrane Fouling ◽

Water Reuse ◽

Reverse Osmosis Membrane

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Comparison of reverse osmosis and nanofiltration membranes in the treatment of biologically treated textile effluent for water reuse

Desalination ◽

10.1016/j.desal.2011.08.023 ◽

2011 ◽

Vol 281 ◽

pp. 372-378 ◽

Cited By ~ 86

Author(s):

Meihong Liu ◽

Zhenhua Lü ◽

Zhihai Chen ◽

Sanchuan Yu ◽

Congjie Gao

Keyword(s):

Reverse Osmosis ◽

Water Reuse ◽

Textile Effluent ◽

Nanofiltration Membranes

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Application of forward osmosis membrane in nanofiltration mode to treat reverse osmosis concentrate from wastewater reclamation plants

Water Science & Technology ◽

10.2166/wst.2018.087 ◽

2018 ◽

Vol 77 (8) ◽

pp. 1990-1997 ◽

Cited By ~ 8

Author(s):

Shahzad Jamil ◽

Sanghyun Jeong ◽

Saravanamuthu Vigneswaran

Keyword(s):

Reverse Osmosis ◽

Organic Compounds ◽

Water Reuse ◽

Inorganic Compounds ◽

Forward Osmosis ◽

Wastewater Reclamation ◽

Permeate Flux ◽

Acid Pretreatment ◽

Inorganic Matter ◽

Gac Adsorption

Abstract Reverse osmosis concentrate (ROC) from wastewater reclamation plants have high concentrations of organic and inorganic compounds, which have to be removed before its disposal. Forward osmosis (FO) and nanofiltration (NF) membranes were tested to treat the ROC for possible water reuse. This research investigated the combined and individual influence of organic and inorganic matter on the fouling of NF and FO membranes. The results revealed that the NF membrane removed most of the organic compounds and some inorganics. The study further highlighted that the FO membrane at NF mode removed the majority of the inorganic compounds and some organics from the ROC. A pretreatment of granulated activated carbon (GAC) adsorption removed 90% of the organic compounds from ROC. In addition, GAC adsorption and acid pretreatment of ROC improved the net water permeate flux by 17% when an FO membrane was used in the NF system. Acid treatment (by bringing the pH down to 5) helped to remove inorganic ions. Therefore, the resultant permeate can be recycled back to the RO water reclamation plant to improve its efficiency.

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