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Full-Text Articles in Science and Technology Studies

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 …


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 …


Enhancement Of Trace Organic Contaminant Degradation By Crude Enzyme Extract From Trametes Versicolor Culture: Effect Of Mediator Type And Concentration, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, Frederic Leusch, Felicity Roddick, S Faraj Magram, William Price, Long Nghiem Sep 2015

Enhancement Of Trace Organic Contaminant Degradation By Crude Enzyme Extract From Trametes Versicolor Culture: Effect Of Mediator Type And Concentration, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, Frederic Leusch, Felicity Roddick, S Faraj Magram, William Price, Long Nghiem

Faisal I Hai

The performance of two redox mediating compounds, namely 1-hydroxybenzotriazole (HBT) and syringaldehyde (SA), was compared in terms of enhancement of enzymatic degradation of a diverse set of 14 phenolic and 16 non-phenolic trace organic contaminants (TrOCs) and the toxicity of the treated media. Extracellular enzyme extract (predominantly containing laccase) from Trametes versicolor culture achieved efficient degradation (70-95%) of nine phenolic and one non-phenolic TrOCs. Mediator dosing extended the spectrum of efficiently degraded TrOCs to 13 phenolic and three non-phenolic compounds, with moderate improvements in removal of a few other non-phenolic compounds. TrOC removal efficiency improved significantly as the HBT dose …


Impact Of 1-Hydroxybenzotriazole Dosing On Trace Organic Contaminant Degradation By Laccase, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, S Faraj Magram, William Price, Long Nghiem Sep 2015

Impact Of 1-Hydroxybenzotriazole Dosing On Trace Organic Contaminant Degradation By Laccase, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, S Faraj Magram, William Price, Long Nghiem

Faisal I Hai

This study investigated the removal of five selected non-phenolic trace organic contaminants (TrOC) by extracellular enzyme extract from a white-rot fungus. Except diclofenac, no other investigated non-phenolic TrOC were degraded by the extracellular enzyme extract. Improvement of enzymatic degradation of all TrOC was achieved in the presence of a redox mediator, namely, 1-hydroxybenzotriazole (HBT). However, the enhancement of degradation was mediator concentration-specific. A significant improvement in degradation at higher dosage than 0.1 mM (HBT) was achieved.


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 …


Rejection And Fate Of Trace Organic Compounds (Trocs) During Membrane Distillation, Kaushalya Wijekoon, Faisal Ibney Hai, Jinguo Kang, William E. Price, Tzahi Cath, Long D. Nghiem Sep 2015

Rejection And Fate Of Trace Organic Compounds (Trocs) During Membrane Distillation, Kaushalya Wijekoon, Faisal Ibney Hai, Jinguo Kang, William E. Price, Tzahi Cath, Long D. Nghiem

Faisal I Hai

In this study, we examined the feasibility of membrane distillation (MD) for removing trace organic compounds (TrOCs) during water and wastewater treatment. A set of 29 compounds was selected to represent major TrOC groups, including pharmaceuticals, steroid hormones, phytoestrogens, UV-filters, industrial chemicals, and pesticides that occur ubiquitously in municipal wastewater. Results reported here suggest that rejection and fate and transport of TrOC during MD are governed by their volatility and, to a lesser extent, hydrophobicity. All TrOCs with pKH > 9 (which can be classified as non-volatile) were well removed by MD. Among the 29 TrOCs investigated in this study, three …


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 …


Effects Of Feed And Draw Solution Temperature And Transmembrane Temperature Difference On The Rejection Of Trace Organic Contaminants By Forward Osmosis, Ming Xie, William E. Price, Long D. Nghiem, Menachem Elimelech Oct 2013

Effects Of Feed And Draw Solution Temperature And Transmembrane Temperature Difference On The Rejection Of Trace Organic Contaminants By Forward Osmosis, Ming Xie, William E. Price, Long D. Nghiem, Menachem Elimelech

William E. Price

The effects of feed and draw solution temperature and transmembrane temperature difference on the rejection of 12 trace organic contaminants (TrOCs) by two forward osmosis (FO) membranes were investigated. The membrane structure parameter (S) and the reverse salt (NaCl) flux selectivity (RSFS) were constant over the temperature range of 20-40 1C, suggesting that within this range, the solution temperature did not significantly influence the membrane polymeric structure. Draw solution properties, including diffusivity, viscosity, and osmotic pressure, played an important role in water and reverse salt (NaCl) flux behaviour and TrOC rejection. Pure water and salt (NaCl) permeability coefficients of the …


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 …


Predicting The Fate Of Emerging Trace Organic Contaminants Of Concern During Mbr Treatment Based On Their Molecular Properties, K C. Wijekoon, L D. Nghiem, F I. Hai, J Kang, W E. Price Oct 2013

Predicting The Fate Of Emerging Trace Organic Contaminants Of Concern During Mbr Treatment Based On Their Molecular Properties, K C. Wijekoon, L D. Nghiem, F I. Hai, J Kang, W E. Price

William E. Price

We demonstrate that the fate of emerging trace organic contaminants during membrane bioreactor (MBR) treatment can be qualitatively predicted by assessing their molecular properties. This work futher expands the qualitative framework for the prdiction of trace organic removal by MBR treatment reported in our recent study.


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 …


Effects Of Caustic Cleaning On Pore Size Of Nanofiltration Membranes And Their Rejection Of Trace Organic Chemicals, Alexander Simon, James A. Mcdonald, Stuart J. Khan, William E. Price, Long D. Nghiem Oct 2013

Effects Of Caustic Cleaning On Pore Size Of Nanofiltration Membranes And Their Rejection Of Trace Organic Chemicals, Alexander Simon, James A. Mcdonald, Stuart J. Khan, William E. Price, Long D. Nghiem

William E. Price

The aim of this study was to assess the impact of caustic cleaning on the rejection of three different trace organic chemical (TrOC) groups (i.e. neutral hydrophilic, neutral hydrophobic and negatively charged) by two nanofiltration (NF) membranes ‒ namely NF270 and NF90. Chemical cleaning was simulated by exposing virgin membrane samples to commercial caustic cleaning formulations as well as sodium hydroxide solutions containing analytical grade additives such as sodium dodecyl sulfate or ethylenediaminetetraacetic acid. The membrane average pore size before and after exposure to a commercially available caustic cleaning formulation was determined based on the pore transport model. The results …


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 …


The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev Oct 2013

The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev

Associate Professor Adam Rennie

We obtain general theorems which enable the calculation of the Dixmier trace in terms of the asymptotics of the zeta function and of the trace of the heat semigroup. We prove our results in a general semi-finite von Neumann algebra. We find for p > 1 that the asymptotics of the zeta function determines an ideal strictly larger than Lp,∞ on which the Dixmier trace may be defined. We also establish stronger versions of other results on Dixmier traces and zeta functions.


Predicting The Fate Of Emerging Trace Organic Contaminants Of Concern During Mbr Treatment Based On Their Molecular Properties, K C. Wijekoon, L D. Nghiem, F I. Hai, J Kang, W E. Price Jul 2013

Predicting The Fate Of Emerging Trace Organic Contaminants Of Concern During Mbr Treatment Based On Their Molecular Properties, K C. Wijekoon, L D. Nghiem, F I. Hai, J Kang, W E. Price

Faisal I Hai

We demonstrate that the fate of emerging trace organic contaminants during membrane bioreactor (MBR) treatment can be qualitatively predicted by assessing their molecular properties. This work futher expands the qualitative framework for the prdiction of trace organic removal by MBR treatment reported in our recent study.


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 …