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Full-Text Articles in Engineering

Removal Of Trace Organic Contaminants By An Mbr Comprising A Mixed Culture Of Bacteria And White-Rot Fungi, Luong Nguyen, Faisal Hai, Shufan Yang, Jinguo Kang, Frederic Leusch, Felicity Roddick, William Price, Long Nghiem Sep 2015

Removal Of Trace Organic Contaminants By An Mbr Comprising A Mixed Culture Of Bacteria And White-Rot Fungi, Luong Nguyen, Faisal Hai, Shufan Yang, Jinguo Kang, Frederic Leusch, Felicity Roddick, William Price, Long Nghiem

Faisal I Hai

The degradation of 30 trace organic contaminants (TrOC) by a white-rot fungus-augmented membrane bioreactor (MBR) was investigated. The results show that white-rot fungal enzyme (laccase), coupled with a redox mediator (1-hydroxy benzotriazole, HBT), could degrade TrOC that are resistant to bacterial degradation (e.g. diclofenac, triclosan, naproxen and atrazine) but achieved low removal of compounds (e.g. ibuprofen, gemfibrozil and amitriptyline) that are well removed by conventional activated sludge treatment. Overall, the fungus-augmented MBR showed better TrOC removal compared to a system containing conventional activated sludge. The major role of biodegradation in removal by the MBR was noted. Continuous mediator dosing to …


Enhancement Of Removal Of Trace Organic Contaminants By Powdered Activated Carbon Dosing Into Membrane Bioreactors, Ngoc Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price, Chul Park, Kazuo Yamamoto Sep 2015

Enhancement Of Removal Of Trace Organic Contaminants By Powdered Activated Carbon Dosing Into Membrane Bioreactors, Ngoc Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price, Chul Park, Kazuo Yamamoto

Faisal I Hai

This study compared the removal efficiency of 22 widespread trace organic contaminants by a laboratory-scale membrane bioreactor (MBR) with and without direct addition of powdered activated carbon (PAC) into the activated sludge reactor over a period of 312 days. The removal of hydrophilic and biologically persistent trace organic contaminants was immediately improved to above 95% after the addition of PAC into MBR. However, a compound-specific gradual decrease in removal underscored the requirement for the addition of fresh PAC. Adsorption onto PAC-added sludge appeared to play a significant role in the relatively more effective aqueous phase removal of a few resistant …


Removal Of Pharmaceuticals, Steroid Hormones, Phytoestrogens, Uv-Filters, Industrial Chemicals And Pesticides By Trametes Versicolor: Role Of Biosorption And Biodegradation, Luong Nguyen, Faisal Ibney Hai, Shufan Yang, Jinguo Kang, Frederic Leusch, Felicity Roddick, William E. Price, Long D. Nghiem Sep 2015

Removal Of Pharmaceuticals, Steroid Hormones, Phytoestrogens, Uv-Filters, Industrial Chemicals And Pesticides By Trametes Versicolor: Role Of Biosorption And Biodegradation, Luong Nguyen, Faisal Ibney Hai, Shufan Yang, Jinguo Kang, Frederic Leusch, Felicity Roddick, William E. Price, Long D. Nghiem

Faisal I Hai

This study reports the removal of 30 diverse trace organic contaminants (TrOC) by live (biosorption þ biodegradation), intracellular enzyme-inhibited and chemically inactivated (biosorption only) whole-cell preparations and the fungal extracellular enzyme extract (predominantly laccase) from Trametes versicolor (ATCC 7731). Because phenolic substrates are amenable to degradation by laccase, all 14 phenolic TrOC were readily biodegraded. On the other hand, only eight of the 16 non-phenolic TrOC were readily biodegraded while the removal of hydrophilic TrOC (log D < 3) was negligible. With the exception of diclofenac, no non-phenolic TrOC were degraded by the extracellular enzyme extract. The whole-cell culture showed considerably …


Wastewater Reuse: Removal Of Emerging Trace Organic Contaminants (Troc), Faisal Hai, Long Nghiem, Stuart Khan, William Price, Kazuo Yamamoto Sep 2015

Wastewater Reuse: Removal Of Emerging Trace Organic Contaminants (Troc), Faisal Hai, Long Nghiem, Stuart Khan, William Price, Kazuo Yamamoto

Faisal I Hai

This chapter reviews current and new technologies for the removal of emerging TrOC from wastewater for reuse purposes. In particular, it compares the relative performance of Membrane bioreactors (MBR) with other conventional biological processes. It is shown that MBR has many intrinsic advantages over other methods leading to superior performance. Fundamental to this is the presence of a membrane barrier which provides a range of other adsorption mechanisms for TrOC. However, in practice there are many factors affecting TrOC removal by MBR, leading to sometimes conflicting reports in the literature from both lab scale studies as well as full scale …


Removal Of Emerging Trace Organic Contaminants By Mbr-Based Hybrid Treatment Processes, Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, William E. Price, Long D. Nghiem Sep 2015

Removal Of Emerging Trace Organic Contaminants By Mbr-Based Hybrid Treatment Processes, Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, William E. Price, Long D. Nghiem

Faisal I Hai

The aim of this study was to demonstrate the complementarity of combining membrane bioreactor (MBR) treatment with UV oxidation or high pressure membrane filtration processes such as nanofiltration (NF) or reverse osmosis (RO) for the removal of trace organic contaminants (TrOC). The results suggest that the removal mechanisms of TrOC by either UV oxidation or NF/RO membrane filtration differ significantly from those of an MBR system. Thus, they can complement MBR treatment very well to significantly improve the removal of TrOC. MBR treatment can effectively remove hydrophobic and readily biodegradable hydrophilic TrOC. The remaining hydrophilic and biologically persistent TrOC were …


Removal And Fate Of Micropollutants In A Sponge-Based Moving Bed Bioreactor, Yunlong Luo, Wenshan Guo, Huu H. Ngo, Long Nghiem, Faisal Ibney Hai, Jinguo Kang, Siqing Xia, Zhiqiang Zhang, William Price Sep 2015

Removal And Fate Of Micropollutants In A Sponge-Based Moving Bed Bioreactor, Yunlong Luo, Wenshan Guo, Huu H. Ngo, Long Nghiem, Faisal Ibney Hai, Jinguo Kang, Siqing Xia, Zhiqiang Zhang, William Price

Faisal I Hai

This study investigated the removal of micropollutants using polyurethane sponge as attached-growth carrier. Batch experiments demonstrated that micropollutants could adsorb to non-acclimatized sponge cubes to varying extents. Acclimatized sponge showed significantly enhanced removal of some less hydrophobic compounds (logD < 2.5), such as ibuprofen, acetaminophen, naproxen, and estriol, as compared with non-acclimatized sponge. The results for bench-scale sponge-based moving bed bioreactor (MBBR) system elucidated compound-specific variation in removal, ranging from 25.9% (carbamazepine) to 96.8% (b-Estradiol 17-acetate) on average. In the MBBR system, biodegradation served as a major removal pathway for most compounds. However, sorption to sludge phase was also a notable …


Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung Sep 2015

Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung

Faisal I Hai

The removal efficiency of 22 selected trace organic contaminants by sequential application of granular activated carbon (GAC) and simultaneous application of powdered activated carbon (PAC) with membrane bioreactor (MBR) was compared in this study. Both sequential application of GAC following MBR treatment (MBR–GAC) and simultaneous application of PAC within MBR (PAC–MBR) achieved improved removal (over 95%) of seven hydrophilic and biologically persistent compounds, which were less efficiently removed by MBR-only treatment (negligible to 70%). However, gradual breakthrough of these compounds occurred over an extended operation period. Charged compounds, particularly, fenoprop and diclofenac, demonstrated the fastest breakthrough (complete and 50–70%, in …


Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem Sep 2015

Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem

Faisal I Hai

This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) system over a period of 196 days. Of the 22 compounds investigated here, all six hydrophilic compounds with electron-withdrawing functional groups (i.e., metronidazole, carbamazepine, ketoprofen, naproxen, fenoprop and diclofenac) exhibited very low removal efficiency by MBR-only treatment. GAC post-treatment initially complemented MBR treatment very well; however, a compound-specific gradual deterioration of the removal of the above-mentioned problematic compounds was noted. While a 20% breakthrough of all four negatively charged compounds namely ketoprofen, naproxen, fenoprop and diclofenac occurred within 1000-3000 bed volumes …


Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price Sep 2015

Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price

Faisal I Hai

the occurrence of trace organics such as pesticides, pharmaceutically active compounds, natural and synthetic hormones as well as varous industrial compounds in the aquatic environment is of great concern due to their potential adverse effects on human health and those of other biota. Therefore, the removal of these compounds from wastewater is an important consideration to ensure safe drinking water and better protection of the environment. In the literature, several techniques have been explored for trace organics removal, namely, conventional activated sludge, membrane bioreactors (MBRs), and absorptioin. However it has been found that neither MBR nor activated carbon on its …


A Novel Membrane Distillation-Thermophilic Bioreactor System: Biological Stability And Trace Organic Compound Removal, Kaushalya Wijekoon, Faisal Hai, Jinguo Kang, William Price, Wenshan Guo, Hao Ngo, Tzahi Cath, Long Nghiem Sep 2015

A Novel Membrane Distillation-Thermophilic Bioreactor System: Biological Stability And Trace Organic Compound Removal, Kaushalya Wijekoon, Faisal Hai, Jinguo Kang, William Price, Wenshan Guo, Hao Ngo, Tzahi Cath, Long Nghiem

Faisal I Hai

The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs …


Biocatalytic Membrane Reactors For The Removal Of Recalcitrant And Emerging Pollutants From Wastewater, F Hai, L Nghiem, O Modin Sep 2015

Biocatalytic Membrane Reactors For The Removal Of Recalcitrant And Emerging Pollutants From Wastewater, F Hai, L Nghiem, O Modin

Faisal I Hai

The potential fields of application of biocatalytic membrane reactors have widened considerably in recent years. Although biocatalytic membrane reactors, in general, are yet to achieve broad industrial application, in the not too far future they are expected to play a major role, not only for the production, transformation and valorization of raw materials but also for environmental remediations. This chapter comprehensively reviews the laboratory scale studies which demonstrate the potential of biocatalytic membrane reactors in wastewater treatment applications. Studies reponed in the literature, however, serve as proof of concept only. Issues that need to be addressed in order to achieve …


Removal Of Bisphenol A And Diclofenac By A Novel Fungal Membrane Bioreactor Operated Under Non-Sterile Conditions, Shufan Yang, Faisal I. Hai, Long D. Nghiem, Luong N. Nguyen, Felicity Roddick, William E. Price Sep 2015

Removal Of Bisphenol A And Diclofenac By A Novel Fungal Membrane Bioreactor Operated Under Non-Sterile Conditions, Shufan Yang, Faisal I. Hai, Long D. Nghiem, Luong N. Nguyen, Felicity Roddick, William E. Price

Faisal I Hai

Previous studies have confirmed significant removal of various trace organic contaminants (TrOCs) by white-rot fungal cultures under sterile batch test conditions. However, little is known about TrOC removal in continuous flow fungal reactors in a non-sterile environment. This study reports the removal of two TrOCs, namely, bisphenol A and diclofenac, by a fungal membrane bioreactor (MBR).


A Review On The Occurrence Of Micropollutants In The Aquatic Environment And Their Fate And Removal During Wastewater Treatment, Yunlong Luo, Wenshan Guo, Huu Hao Ngo, Long Duc Nghiem, Faisal Ibney Hai, Jian Zhang, Shuang Liang, Xiaochang C. Wang Sep 2015

A Review On The Occurrence Of Micropollutants In The Aquatic Environment And Their Fate And Removal During Wastewater Treatment, Yunlong Luo, Wenshan Guo, Huu Hao Ngo, Long Duc Nghiem, Faisal Ibney Hai, Jian Zhang, Shuang Liang, Xiaochang C. Wang

Faisal I Hai

Micropollutants are emerging as a new challenge to the scientific community. This review provides a summary of the recent occurrence of micropollutants in the aquatic environment including sewage, surface water, groundwater and drinking water. The discharge of treated effluent from WWTPs is a major pathway for the introduction of micropollutants to surface water. WWTPs act as primary barriers against the spread of micropollutants. WWTP removal efficiency of the selected micropollutants in 14 countries/regions depicts compound-specific variation in removal, ranging from 12.5 to 100%. Advanced treatment processes, such as activated carbon adsorption, advanced oxidation processes, nanofiltration, reverse osmosis, and membrane bioreactors …


Estimation Of The Effect Of Catalyst Physical Characteristics On Fenton-Like Oxidation Efficiency Using Adaptive Neuro-Fuzzy Computing Technique Dec 2014

Estimation Of The Effect Of Catalyst Physical Characteristics On Fenton-Like Oxidation Efficiency Using Adaptive Neuro-Fuzzy Computing Technique

Faculty of Engineering University of Malaya

Catalyst size, which determines surface area, is one of the major factors in catalytic performance. In this study, response surface methodology (RSM) and an adaptive neuro-fuzzy inference system (ANFIS) were applied to quantify the effects of physical characteristics of magnetite on Fenton-like oxidation efficiency of methylene blue. For this purpose, two magnetite samples (M and N) were used and characterized by XRD, BET surface area, particle size analyzer and FE-SEM. Central composite design (CCD) was applied to design the experiments, develop regression models, optimize and evaluate the individual and interactive effects of five independent variables: H2O2 and catalyst concentrations, pH, …


Removal Of Boron, Fluoride And Nitrate By Electrodialysis In The Presence Of Organic Matter, Laura J. Banasiak, Andrea I. Schafer Aug 2014

Removal Of Boron, Fluoride And Nitrate By Electrodialysis In The Presence Of Organic Matter, Laura J. Banasiak, Andrea I. Schafer

Laura J Banasiak Dr

The removal of the trace inorganic contaminants boron (B(OH)4−), fluoride (F−) and nitrate (NO3−) from synthetic aqueous solutions containing organic matter using electrodialysis was investigated. The transport of the contaminants through the ion-exchange membranes was evaluated in relation to hydrated ionic radius, whereby a positive correlation was found in absence of organic matter. NO3−, with the smaller hydrated ionic radius and weaker hydration shell, was removed more effectively than F−, which has a larger hydrated ionic radius and stronger hydration shell. The removal of F− and NO3− was not significantly influenced by solution pH due to their pH independent speciation. …


Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem Oct 2013

Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem

William E. Price

This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) system over a period of 196 days. Of the 22 compounds investigated here, all six hydrophilic compounds with electron-withdrawing functional groups (i.e., metronidazole, carbamazepine, ketoprofen, naproxen, fenoprop and diclofenac) exhibited very low removal efficiency by MBR-only treatment. GAC post-treatment initially complemented MBR treatment very well; however, a compound-specific gradual deterioration of the removal of the above-mentioned problematic compounds was noted. While a 20% breakthrough of all four negatively charged compounds namely ketoprofen, naproxen, fenoprop and diclofenac occurred within 1000-3000 bed volumes …


Understanding The Factors Controlling The Removal Of Trace Organic Contaminants By White-Rot Fungi And Their Lignin Modifying Enzymes: A Critical Review, Shufan Yang, Faisal I. Hai, Long D. Nghiem, William E. Price, Felicity Roddick, Maria T. Moreira, Saleh F. Magram Oct 2013

Understanding The Factors Controlling The Removal Of Trace Organic Contaminants By White-Rot Fungi And Their Lignin Modifying Enzymes: A Critical Review, Shufan Yang, Faisal I. Hai, Long D. Nghiem, William E. Price, Felicity Roddick, Maria T. Moreira, Saleh F. Magram

William E. Price

White-rot fungi (WRF) and their lignin modifying enzymes (LME) can degrade a wide range of trace organic contaminants (TrOC), which are suspected to cause adverse health effects in humans and other biota. Recent studies have successfully applied either whole-cell WRF or their extracellular culture extract to remove TrOC from the aqueous phase. TrOC removal by a WRF system is dependent on a range of factors including molecular structure of the TrOC, fungal species and their specific LME, culture medium composition, and methods to enhance fungal degradation capacity; however, the specific relationships between these factors have not been systematically delineated. The …


Removal Of Trace Organic Contaminants By An Mbr Comprising A Mixed Culture Of Bacteria And White-Rot Fungi, Luong N. Nguyen, Faisal I. Hai, Shufan Yang, Jinguo Kang, Frederic D L Leusch, Felicity Roddick, William E. Price, Long D. Nghiem Oct 2013

Removal Of Trace Organic Contaminants By An Mbr Comprising A Mixed Culture Of Bacteria And White-Rot Fungi, Luong N. Nguyen, Faisal I. Hai, Shufan Yang, Jinguo Kang, Frederic D L Leusch, Felicity Roddick, William E. Price, Long D. Nghiem

William E. Price

The degradation of 30 trace organic contaminants (TrOC) by a white-rot fungus-augmented membrane bioreactor (MBR) was investigated. The results show that white-rot fungal enzyme (laccase), coupled with a redox mediator (1-hydroxy benzotriazole, HBT), could degrade TrOC that are resistant to bacterial degradation (e.g. diclofenac, triclosan, naproxen and atrazine) but achieved low removal of compounds (e.g. ibuprofen, gemfibrozil and amitriptyline) that are well removed by conventional activated sludge treatment. Overall, the fungus-augmented MBR showed better TrOC removal compared to a system containing conventional activated sludge. The major role of biodegradation in removal by the MBR was noted. Continuous mediator dosing to …


Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung Oct 2013

Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung

William E. Price

The removal efficiency of 22 selected trace organic contaminants by sequential application of granular activated carbon (GAC) and simultaneous application of powdered activated carbon (PAC) with membrane bioreactor (MBR) was compared in this study. Both sequential application of GAC following MBR treatment (MBR–GAC) and simultaneous application of PAC within MBR (PAC–MBR) achieved improved removal (over 95%) of seven hydrophilic and biologically persistent compounds, which were less efficiently removed by MBR-only treatment (negligible to 70%). However, gradual breakthrough of these compounds occurred over an extended operation period. Charged compounds, particularly, fenoprop and diclofenac, demonstrated the fastest breakthrough (complete and 50–70%, in …


Removal Of N-Nitrosamines By An Aerobic Membrane Bioreactor, Kaushalya C. Wijekoon, Takahiro Fujioka, James A. Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long D. Nghiem Oct 2013

Removal Of N-Nitrosamines By An Aerobic Membrane Bioreactor, Kaushalya C. Wijekoon, Takahiro Fujioka, James A. Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long D. Nghiem

William E. Price

This study investigated the fate of eight N-nitrosamines during membrane bioreactor (MBR) treatment. The results suggest that biodegradation is mainly responsible for the removal of N-nitrosamines during MBR treatment. Other removal mechanisms were insignificant (e.g. adsorption to sludge) or not expected (e.g. photolysis and volatilization) given the experimental conditions and physicochemical properties of the N-nitrosamines studied here. N-nitrosamine removal efficiencies were from 24% to 94%, depending on their molecular properties. High removal of N-nitrosamines such as N-nitrosodimethylamine and N-nitrosodiethylamine could be explained by the presence of strong electron donating functional groups (EDG) in their structure. In contrast, N-nitrosomorpholine possessing the …


Removal Of Trace Organic Contaminants By A Membrane Bioreactor-Granular Activated Carbon (Mbr -Gac) System, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, William E. Price, Long Nghiem Jul 2013

Removal Of Trace Organic Contaminants By A Membrane Bioreactor-Granular Activated Carbon (Mbr -Gac) System, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, William E. Price, Long Nghiem

Faisal I Hai

The removal of trace organics by a membrane bioreactor–granular activated carbon (MBR–GAC) integrated system were investigated. The results confirmed that MBR treatment can be effective for the removal of hydrophobic (logD > 3.2) and readily biodegradable trace organics. The data also highlighted the limitation of MBR in removing hydrophilic and persistent compounds (e.g. carbamazepine, diclofenac, and fenoprop) and that GAC could complement MBR very well as a post-treatment process. The MBR– GAC system showed high removal of all selected trace organics including those that are hydrophilic and persistent to biological degradation at up to 406 bed volumes (BV). However, over an …


Understanding The Factors Controlling The Removal Of Trace Organic Contaminants By White-Rot Fungi And Their Lignin Modifying Enzymes: A Critical Review, Shufan Yang, Faisal Hai, Long Nghiem, William Price, Felicity Roddick, Maria Moreira, Saleh Magram Jul 2013

Understanding The Factors Controlling The Removal Of Trace Organic Contaminants By White-Rot Fungi And Their Lignin Modifying Enzymes: A Critical Review, Shufan Yang, Faisal Hai, Long Nghiem, William Price, Felicity Roddick, Maria Moreira, Saleh Magram

Faisal I Hai

White-rot fungi (WRF) and their lignin modifying enzymes (LME) can degrade a wide range of trace organic contaminants (TrOC), which are suspected to cause adverse health effects in humans and other biota. Recent studies have successfully applied either whole-cell WRF or their extracellular culture extract to remove TrOC from the aqueous phase. TrOC removal by a WRF system is dependent on a range of factors including molecular structure of the TrOC, fungal species and their specific LME, culture medium composition, and methods to enhance fungal degradation capacity; however, the specific relationships between these factors have not been systematically delineated. The …


Enhanced Biological Phosphorus Removal And Its Modeling For The Activated Sludge And Membrane Bioreactor Processes, M F. R Zuthi, W S. Guo, H H. Ngo, L D. Nghiem, F I. Hai Jul 2013

Enhanced Biological Phosphorus Removal And Its Modeling For The Activated Sludge And Membrane Bioreactor Processes, M F. R Zuthi, W S. Guo, H H. Ngo, L D. Nghiem, F I. Hai

Faisal I Hai

A modified activated sludge process (ASP) for enhanced biological phosphorus removal (EBPR) needs to sustain stable performance for wastewater treatment to avoid eutrophication in the aquatic environment. Unfortunately, the overall efficiency of the EBPR in ASPs and membrane bioreactors (MBRs) is frequently hindered by different operational/system constraints. Moreover, although phosphorus removal data from several wastewater treatment systems are available, a comprehensive mathematical model of the process is still lacking. This paper presents a critical review that highlights the core issues of the biological phosphorus removal in ASPs and MBRs while discussing the inhibitory process requirements for other nutrients' removal. This …


Pesticide Removal By A Mixed Culture Of Bacteria And White-Rot Fungi, Faisal I. Hai, Oska Modin, Kazuo Yamamoto, Kensuke Fukushi, Fumiyuki Nakajiam, Long Nghiem Jul 2013

Pesticide Removal By A Mixed Culture Of Bacteria And White-Rot Fungi, Faisal I. Hai, Oska Modin, Kazuo Yamamoto, Kensuke Fukushi, Fumiyuki Nakajiam, Long Nghiem

Faisal I Hai

Combining activated sludge cultures with microbes harboring specific degradation pathways could constitute a relevant process for the removal of toxic and recalcitrant organic substances from wastewater. Enhanced removal of three widely used recalcitrant pesticides from their liquid mixture was demonstrated by implementing a non-acclimated mixed culture of bacteria and white-rot fungus. During an incubation period of 14 days, the mixed fungus–bacteria culture achieved 47, 98, and 62% removal of aldicarb, atrazine and alachlor from the liquid phase, respectively. This compared favorably to batches containing only non-acclimated fungus or previously published removal rates with nonacclimated bacterial cultures. Biosorption along with biodegradation …


Chemical Coagulation-Based Processes For Trace Organic Contaminant Removal: Current State And Future Potential, Jonathan T. Alexander, Faisal I. Hai, Turki M. Al-Aboud Jul 2013

Chemical Coagulation-Based Processes For Trace Organic Contaminant Removal: Current State And Future Potential, Jonathan T. Alexander, Faisal I. Hai, Turki M. Al-Aboud

Faisal I Hai

Trace organic contaminants have become an increasing cause of concern for governments and water authorities as they attempt to respond to the potential challenges posed by climate change by implementing sustainable water cycle management practices. The augmentation of potable water supplies through indirect potable water reuse is one such method currently being employed. Given the uncertainty surrounding the potential human health impacts of prolonged ingestion of trace organic contaminants, it is vital that effective and sustainable treatment methods are utilized. The purpose of this article is to provide a comprehensive literature review of the performance of the chemical coagulation process …


Performance Of A Novel Osmotic Membrane Bioreactor (Ombr) System: Flux Stability And Removal Of Trace Organics, Abdulhakeem Alturki, James Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long Nghiem Jul 2013

Performance Of A Novel Osmotic Membrane Bioreactor (Ombr) System: Flux Stability And Removal Of Trace Organics, Abdulhakeem Alturki, James Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long Nghiem

Faisal I Hai

Results reported here highlight the potential and several challenges in the development of a novel osmotic membrane bioreactor (OMBR) process for the treatment of municipal wastewater. Following the initial gradual decline, a stable permeate flux value was obtained after approximately four days of continuous operation. There was evidence of continuous deterioration of biological activity of the OMBR system, possibly due to the build-up of salinity in the reactor. The removal of 25 out of 27 trace organic compounds with molecular weight higher than 266 g/mol was above 80% and was possibly governed by the interplay between physical separation of the …


Removal Of N-Nitrosamines By An Aerobic Membrane Bioreactor, Kaushalya C. Wijekoon, Takahiro Fujioka, James A. Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long D. Nghiem Jul 2013

Removal Of N-Nitrosamines By An Aerobic Membrane Bioreactor, Kaushalya C. Wijekoon, Takahiro Fujioka, James A. Mcdonald, Stuart J. Khan, Faisal I. Hai, William E. Price, Long D. Nghiem

Faisal I Hai

This study investigated the fate of eight N-nitrosamines during membrane bioreactor (MBR) treatment. The results suggest that biodegradation is mainly responsible for the removal of N-nitrosamines during MBR treatment. Other removal mechanisms were insignificant (e.g. adsorption to sludge) or not expected (e.g. photolysis and volatilization) given the experimental conditions and physicochemical properties of the N-nitrosamines studied here. N-nitrosamine removal efficiencies were from 24% to 94%, depending on their molecular properties. High removal of N-nitrosamines such as N-nitrosodimethylamine and N-nitrosodiethylamine could be explained by the presence of strong electron donating functional groups (EDG) in their structure. In contrast, N-nitrosomorpholine possessing the …


Removal Of Heavy Metals From Mining Impacted Water By An Electrocoagulation-Ultrafiltration Hybrid Process, Long Nghiem, Duminda Kumarasinghe, Liam Pettigrew Dec 2012

Removal Of Heavy Metals From Mining Impacted Water By An Electrocoagulation-Ultrafiltration Hybrid Process, Long Nghiem, Duminda Kumarasinghe, Liam Pettigrew

Long D Nghiem

In this study, the use of an electrocoagulation-ultrafiltration (EC-UF) hybrid system for the treatment of mining impacted wastewater was investigated. A model wastewater solution containing copper, lead, cadmium and other constituents representative of mining impacted wastewater was used in this investigation. The effects of key operational parameters including electrolysis time, current density, and solution pH on the performance of the EC and EC-UF systems were systematically investigated. The removal rates of copper and lead by the EC process were consistently higher than that of cadmium. It is probable that the removal mechanism of cadmium was different from that of the …


Effects Of Membrane Degradation On The Removal Of Pharmaceutically Active Com#163s (Phacs) By Nf/Ro Filtration Processes, Alexander Simon, Long Nghiem, Pierre Le-Clech, Stuart J. Khan, Jorg E. Drewes Dec 2012

Effects Of Membrane Degradation On The Removal Of Pharmaceutically Active Com#163s (Phacs) By Nf/Ro Filtration Processes, Alexander Simon, Long Nghiem, Pierre Le-Clech, Stuart J. Khan, Jorg E. Drewes

Long D Nghiem

The impacts of membrane degradation due to chlorine attack on the rejection of pharmaceutically active compounds (PhACs) by nanofiltration and reverse osmosis membranes were investigated in this study. Membrane degradation was simulated by soaking the membranes in a sodium hypochlorite solution of various concentrations over 18 h. Changes in membrane surface properties were characterised by contact angle measurement, atomic force microscopy analysis, and streaming potential measurement. The impacts of hypochlorite exposure to the membrane separation processes were ascertained by comparing the rejection of PhACs by virgin and chlorine-exposed membranes. Overall, the reverse osmosis BW30 membrane and the tight nanofiltration NF90 …


Removal Of Trace Organics By Mbr Treatment: The Role Of Molecular Properties, Nichanan Tadkaew, Faisal Hai, James Mcdonald, Stuart J. Khan, Long Nghiem Dec 2012

Removal Of Trace Organics By Mbr Treatment: The Role Of Molecular Properties, Nichanan Tadkaew, Faisal Hai, James Mcdonald, Stuart J. Khan, Long Nghiem

Long D Nghiem

This study examined the relationship between specific molecular features of trace organic contaminants and their removal efficiencies by a laboratory scale membrane bioreactor (MBR). Removal efficiencies of 40 trace organic compounds were assessed under stable operating conditions. The reported results demonstrate an apparent correlation between chemical structures and the removal of trace organic contaminants by the laboratory scale MBR system. The removal of all 14 very hydrophobic (Log D > 3.2) trace organic compounds selected in this study was consistently high and was above 85%. The occurrence and types of electron withdrawing or donating functional groups appear to be important factors …