Aghayarzadeh, M, Khabbaz, H, Fatahi, B & Terzaghi, S 2020, 'Interpretation of Dynamic Pile Load Testing for Open-Ended Tubular Piles Using Finite-Element Method', INTERNATIONAL JOURNAL OF GEOMECHANICS, vol. 20, no. 2.
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Ahmed, MB, Alam, MM, Zhou, JL, Xu, B, Johir, MAH, Karmakar, AK, Rahman, MS, Hossen, J, Hasan, ATMK & Moni, MA 2020, 'Advanced treatment technologies efficacies and mechanism of per-and poly-fluoroalkyl substances removal from water', PROCESS SAFETY AND ENVIRONMENTAL PROTECTION, vol. 136, pp. 1-14.
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Ajani, PA, Lim, HC, Verma, A, Lassudrie, M, McBean, K, Doblin, MA & Murray, SA 2020, 'First report of the potentially toxic marine diatom Pseudo-nitzschia simulans (Bacillariophyceae) from the East Australian Current', Phycological Research.
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© 2020 Japanese Society of Phycology Certain species of the marine diatom genus Pseudo-nitzschia are responsible for the production of the domoic acid (DA), a neurotoxin that can bioaccumulate in the food chain and cause amnesic shellfish poisoning (ASP) in animals and humans. This study extends our knowledge by reporting on the first observation of the potentially toxic species Pseudo-nitzschia simulans from this region. One clonal strain of P. simulans was isolated from the East Australian Current and characterized using light and transmission electron microscopy, and phylogenetic analyses based on regions of the internal transcribed spacer (ITS) and the D1–D3 region of the large subunit (LSU) of the nuclear-encoded ribosomal deoxyribonucleic acid (rDNA), as well as examined for DA production as measured by liquid chromatography–mass spectrometry. Although this strain was non-toxic under the defined growth conditions, the results unambiguously confirmed that this isolate is the potentially toxic species P. simulans – the first report of this species from the Southern Hemisphere.
Akther, N, Yuan, Z, Chen, Y, Lim, S, Phuntsho, S, Ghaffour, N, Matsuyama, H & Shon, H 2020, 'Influence of graphene oxide lateral size on the properties and performances of forward osmosis membrane', Desalination, vol. 484.
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© 2020 Elsevier B.V. Graphene oxide (GO) has been widely explored for the improvement of thin-film composite (TFC) membrane performance. However, the influences of GO flake lateral size on the polyamide (PA) TFC membrane properties and performances have not been investigated. In this study, GO suspensions with an average flake size ranging from 0.01 to 1.06 μm2 were prepared by varying the sonication duration between 0 and 8 h. The different sized GO flakes were embedded in the PA layer to examine the effect of their size on the morphology and performances of TFC forward osmosis (FO) membranes. The specific reverse solute flux and water flux of the GO-modified thin-film nanocomposite (TFN) membranes improved by over 60% and 50%, respectively, when the average GO flake size was reduced from 1.06 to 0.01 μm2 due to the formation of a thinner and more uniform PA layer. Large GO flakes deteriorated membrane performance by creating impervious regions that obstructed the reaction between monomers during the interfacial polymerization process resulting in defective PA layer formation. Whereas, smaller GO flakes distributed more uniformly in the PA layer creating fewer defects, and demonstrated better desalination performance and antifouling property than the TFN membranes modified with larger GO flakes. These results deliver strategies for future improvements in GO or 2D nanomaterial-based TFN membranes, where smaller flake size can be beneficial for minimizing PA layer defects.
Alam, MM, Hossain, MA, Hossain, MD, Johir, MAH, Hossen, J, Rahman, MS, Zhou, JL, Hasan, ATMK, Karmakar, AK & Ahmed, MB 2020, 'The Potentiality of Rice Husk-Derived Activated Carbon: From Synthesis to Application', PROCESSES, vol. 8, no. 2.
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Alanezi, AA, Altaee, A & Sharif, AO 2020, 'The effect of energy recovery device and feed flow rate on the energy efficiency of reverse osmosis process', Chemical Engineering Research and Design.
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Al-Jubainawi, A, Ma, Z, Guo, Y & Nghiem, LD 2020, 'Effect of regulating main governing factors on the selectivity membranes of electrodialysis used for LiCl liquid desiccant regeneration', JOURNAL OF BUILDING ENGINEERING, vol. 28.
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Alosime, EM, Alshahrani, AA, Nghiem, LD & Panhuis, M 2020, 'The preparation and characterization of buckypaper made from carbon nanotubes impregnated with chitosan', Polymer Composites.
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Alshahrani, AA, Algamdi, MS, Alsohaimi, IH, Nghiem, LD, Tu, KL, Al-Illwajfeh, AE & Panhuis, MIH 2020, 'The rejection of mono- and di-valent ions from aquatic environmental by MWNT/chitosan buckypaper composite membranes: Influences of chitosan concentrations', SEPARATION AND PURIFICATION TECHNOLOGY, vol. 234.
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Altaee, A 2020, 'Organic Fouling in Forward Osmosis: A Comprehensive Review', Water, vol. 12, no. 5.
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Altaee, A & AlZainati, N 2020, 'Novel Thermal Desalination Brine Reject-Sewage Effluent Salinity Gradient for Power Generation and Dilution of Brine Reject', Energies, vol. 13, no. 7.
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Salinity gradient resource presents an essential role for power generated in the process of pressure-retarded osmosis (PRO). Researchers proposed several designs for coupling the PRO process with the desalination plants, particularly reverse osmosis technology for low-cost desalination but there is no study available yet on the utilization of the concentrated brine reject from a thermal desalination plant. This study evaluates the feasibility of power generation in the PRO process using thermal plant brine reject-tertiary sewage effluent (TSE) salinity gradient resource. Power generation in the PRO process was determined for several commercially available FO membranes. Water flux in Oasys Forward Osmosis membrane was more than 31 L/m2h while the average water flux in the Oasys module was 17 L/m2h. The specific power generation was higher in the thin film composite (TFC) membranes compared to the cellulose triacetate (CTA) membranes. The specific power generation for the Oasys membrane was 0.194 kWh/m3, which is 41% of the maximum Gibbs energy of the brine reject-TSE salinity gradient. However, the Hydration Technology Innovation CTA membrane extracted only 0.133 kWh/m3 or 28% of Gibbs free energy of mixing for brine reject-TSE salinity gradient. The study reveals the potential of the brine reject-TSE salinity gradient resource for power generation and the dilution of brine reject.
Altaee, A, Khalaifat, N & Zhou, J 2020, 'Assessment of wind energy potential at Yanco, New South Wales, Australia', International Journal of Industrial Electronics and Electrical Engineering, vol. 8, no. 1, pp. 26-30.
Altaee, A, Khlaifat, N, Zhou, J, Huang, Y & Braytee, A 2020, 'Optimization of a Small Wind Turbine for a Rural Area: A Case Study of Deniliquin, New South Wales, Australia', Energies, vol. 13.
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The performance of a wind turbine is profoundly affected by wind conditions. Small wind turbines usually achieve the demand for electricity in rural areas. The shape of the blade greatly influences the performance of the wind turbine. The present study aims to optimize the performance of a 20 kW horizontal-axis wind turbine (HAWT) under local wind conditions at Deniliquin, New South Wales, Australia. ANSYS Fluent was used to investigate the aerodynamic performance of the 20 KW HAWT. The effects of four Reynolds Averaged Navier Stokes (RANS) turbulence models on predicting the flow over the wind turbine under separation condition were examined. Transition SST model had the best agreement with NREL CER data, which was used to investigate the mechanical output at different rotational speeds and variable pitch angles. Then the aerodynamic shape of the rotor of the wind turbine was optimized to maximize the annual energy production (AEP) in the Deniliquin region. Statistical wind analysis was applied to define the Weibull function and scale parameters which were 2.096 and 5.042 m/s, respectively. HARP_Opt was enhanced with design variables concerning the shape of the blade, rated rotational speed, and pitch angle. Pitch angle remained at 0ᵒ while the rising wind speed improved rotor speed to 148.4482 rpm at rated speed. This optimization improved the AEP rate by 9.068% when compared to the original NREL design.
Arjmandi, A, Peyravi, M, Arjmandi, M & Altaee, A 2020, 'Exploring the use of cheap natural raw materials to reduce the internal concentration polarization in thin-film composite forward osmosis membranes', Chemical Engineering Journal, pp. 125483-125483.
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Arjmandi, M, Altaee, A, Arjmandi, A, Chenar, MP, Peyravi, M & Jahanshahi, M 2020, 'A facile and efficient approach to increase the magnetic property of MOF-5', Solid State Sciences, pp. 106292-106292.
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Arjmandi, M, Peyravi, M, Altaee, A, Arjmandi, A, Pourafshari Chenar, M, Jahanshahi, M & Binaeian, E 2020, 'A state-of-the-art protocol to minimize the internal concentration polarization in forward osmosis membranes', Desalination, vol. 480.
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© 2020 Elsevier B.V. The main reason for the lower water flux, than expected, in the forward osmosis (FO) process, is the internal concentration polarization (DICP). Usually, the structural parameter (S) is used as an indicator of the intensity of DICP. Small S value is desirable for the FO membrane due to the low DICP. However, due to design and construction problems, structural parameter reduction has some drawbacks. In this work, DICP reduction in FO membranes will be investigated using an approach other than structural parameter reduction. Accordingly, during the FO process, the feed solution (FS) valve is opened and closed at a constant period of time (feed valve timing (FVT)). Four types of FO membranes with different S parameters were used. The effects of the implementation of the proposed protocol on the water flux (Jw), reverse salt flux (Js), specific reverse solute flux (Js/Jw) and effective driving force were investigated. The effects of the S parameter and draw solution (DS) concentration also investigated separately. The results showed that the proposed protocol significantly increased Jw. Also, the values of Js/Jw decreased with increasing the FVT values and reached the lowest level in the practical recovery time (PRT).
Ball, J, Qiuhua, L, Jingming, H, Bingyao, L, Yu, T, Hui, L & Liping, M 2020, 'Cause Analysis for a New Type of Devastating Flash Flood', Hydrology Research: an international journal, vol. 51, no. 1, pp. 1-16.
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This work introduces an unprecedented flash flood that resulted in nine casualties in Shimen Valley, China, 2015. Through field survey and numerical simulation, the causes of the disaster are systematically analyzed, finding that the intense storm, terrain features, and the large woody debris(LWD) played important roles. The intense storm induced fast runoff and, in turn, high discharges as a result of the steep catchment surfaces and channels. The flood flushed LWD and boulders downstream until blockage occurred in a contraction section, forming a debris lake. When the debris dam broke, a dam break wave rapidly propagated to the valley mouth, washing people away. After considering the disaster-inducing factors, measures for preventing similar floods are proposed. The analysis presented herein should help others manage flash floods in mountain areas.
Bao, T, Damtie, MM, Hosseinzadeh, A, Wei, W, Jin, J, Hoang, NPV, Ye, JS, Liu, Y, Wang, XF, Yu, ZM, Chen, ZJ, Wu, K, Frost, RL & Ni, B-J 2020, 'Bentonite-supported nano zero-valent iron composite as a green catalyst for bisphenol A degradation: Preparation, performance, and mechanism of action', JOURNAL OF ENVIRONMENTAL MANAGEMENT, vol. 260.
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Barolo, L, Abbriano, RM, Commault, AS, George, J, Kahlke, T, Fabris, M, Padula, MP, Lopez, A, Ralph, PJ & Pernice, M 2020, 'Perspectives for Glyco-Engineering of Recombinant Biopharmaceuticals from Microalgae', CELLS, vol. 9, no. 3.
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Bian, Y, Wang, D, Liu, X, Yang, Q, Liu, Y, Wang, Q, Ni, BJ, Li, H & Zhang, Y 2020, 'The fate and impact of TCC in nitrifying cultures', Water Research, vol. 178.
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© 2020 Elsevier Ltd Triclocarban (TCC) is a highly effective antibacterial agent, which is widely used in a variety of applications and present at significant levels (e.g., 760 μg/L) in wastewater worldwide. However, the interaction between TCC and nitrifiers, important microbial cultures in wastewater treatment plants, has not been documented. This work therefore aimed to evaluate the fate of TCC in a nitrifying culture and its impact on nitrifiers in four long-term nitrifiers-rich reactors, which received synthetic wastewater containing 0, 0.1, 1, or 5 mg/L TCC. Experimental results showed that 36.7%–50.7% of wastewater TCC was removed by nitrifying cultures in stable operation. Mass balance analysis revealed that the removal of TCC was mainly achieved through adsorption rather than biodegradation. Adsorption kinetic analysis indicated that inhomogeneous multilayer adsorption was responsible for the removal while fourier transform infrared spectroscopy indicated that several functional groups such as hydroxyl, amide and polysaccharide seemed to be the main adsorption sites. The adsorbed TCC significantly deteriorated settleability and performance of nitrifying cultures. With an increase of influent TCC from 0 to 5 mg/L, reactor volatile suspended solids and effluent nitrate decreased from 1200 ± 90 mg/L and 300.81 ± 7.52 mg/L to 880 ± 80 and 7.35 ± 4.62 mg/L while effluent ammonium and nitrite increased from 0.41 ± 0.03 and 0.45 ± 0.23 mg/L to104.65 ± 3.46 and 182.06 ± 7.54 mg/L, respectively. TCC increased the extracellular polymeric substances of nitrifying cultures, inhibited the specific activities of nitrifiers, and altered the abundance of nitrifiers especially Nitrospira sp. In particular, TCC at environmentally relevant concentration (i.e., 0.1 mg/L) significantly inhibited NOB activity and reduced NOB population.
Chang, Z, Long, G, Zhou, JL & Ma, C 2020, 'Valorization of sewage sludge in the fabrication of construction and building materials: A review', Resources, Conservation and Recycling, vol. 154.
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© 2019 Elsevier B.V. With increasing amount of sewage sludge becoming an urgent and inevitable issue for every country, its applications in the production of construction and building materials provide an alternative solution for sludge disposal and resource recovery. Similar to clay and Portland cement, the main oxides in sewage sludge are SiO2 (10–25 %), Al2O3 (5–10 %) and CaO (10–30 %) which are increased in sludge ash after incineration to 25–50 %, 10–20 % and 15–30 %. Therefore, this solid waste can be utilized not only as raw material for the production of eco-cement, bricks, ceramic materials and lightweight aggregates through sintering process, but also as supplementary admixtures in cementitious materials such as pozzolanic component, fine aggregate or filling material. By critically reviewing current utilizations of sewage sludge, it is feasible to replace up to 15 % natural raw materials with sewage sludge in cement production and the manufactured eco-cement clinkers show comparable performance to traditional Portland cement. Whilst as raw feed in the fabrication of bricks, ceramic materials and lightweight aggregates, 20 % of sewage sludge substitution is acceptable to produce good quality products (within 8 % firing shrinkage and 15 % water absorption). Though high content of organic matter in raw sludge causes a decrease in mechanical strength and delay in hydration process, controlled low-strength materials offer an innovative reuse with large amount of sludge. The immobilization of heavy metals in products prevents sewage sludge causing secondary environmental pollution. Furthermore, suggestions for future research are proposed in order to strengthen the high value-added applications of sewage sludge.
Cheng, D, Hao Ngo, H, Guo, W, Wang Chang, S, Duc Nguyen, D, Liu, Y, Zhang, X, Shan, X & Liu, Y 2020, 'Contribution of antibiotics to the fate of antibiotic resistance genes in anaerobic treatment processes of swine wastewater: A review', Bioresource Technology, vol. 299.
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© 2019 Elsevier Ltd Antibiotic resistance genes (ARGs) in water environment have become a global health concern. Swine wastewater is widely considered to be one of the major contributors for promoting the proliferation of ARGs in water environments. This paper comprehensively reviews and discusses the occurrence and removal of ARGs in anaerobic treatment of swine wastewater, and contributions of antibiotics to the fate of ARGs. The results reveal that ARGs’ removal is unstable during anaerobic processes, which negatively associated with the presence of antibiotics. The abundance of bacteria carrying ARGs increases with the addition of antibiotics and results in the spread of ARGs. The positive relationship was found between antibiotics and the abundance and transfer of ARGs in this review. However, it is necessary to understand the correlation among antibiotics, ARGs and microbial communities, and obtain more knowledge about controlling the dissemination of ARGs in the environment.
Cheng, D, Huu, HN, Guo, W, Chang, SW, Dinh, DN, Zhang, X, Varjani, S & Liu, Y 2020, 'Feasibility study on a new pomelo peel derived biochar for tetracycline antibiotics removal in swine wastewater', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 720.
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Cheng, D, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Liu, Y, Shan, X, Nghiem, LD & Nguyen, LN 2020, 'Removal process of antibiotics during anaerobic treatment of swine wastewater.', Bioresource technology, vol. 300, pp. 122707-122707.
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High concentrations of antibiotics in swine wastewater pose potentially serious risks to the environment, human and animal health. Identifying the mechanism for removing antibiotics during the anaerobic treatment of swine wastewater is essential for reducing the serious damage they do to the environment. In this study, batch experiments were conducted to investigate the biosorption and biodegradation of tetracycline and sulfonamide antibiotics (TCs and SMs) in anaerobic processes. Results indicated that the removal of TCs in the anaerobic reactor contributed to biosorption, while biodegradation was responsible for the SMs' removal. The adsorption of TCs fitted well with the pseudo-second kinetic mode and the Freundlich isotherm, which suggested a heterogeneous chemisorption process. Cometabolism was the main mechanism for the biodegradation of SMs and the process fitted well with the first-order kinetic model. Microbial activity in the anaerobic sludge might be curtailed due to the presence of high concentrations of SMs.
Cheng, D, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Liu, Y, Wei, Q & Wei, D 2020, 'A critical review on antibiotics and hormones in swine wastewater: Water pollution problems and control approaches.', Journal of Hazardous Materials, vol. 387.
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Swine wastewater (SW) is an important source of antibiotics and hormones (A&H) in the environment due to their large-scale application in swine industry. A&H in SW can be released into the water environment through the direct discharge of SW, effluent from SW treatment plants, and runoff and leaching from farmland polluted by swine wastes. The presence of A&H in the water environment has become an increasing global concern considering their adverse effects to the aquatic organism and human. This review critically discusses: (i) the occurrence of A&H in global water environment and their potential risks to water organisms and human; (ii) the management and technical approaches for reducing the emission of A&H in SW to the water environment. The development of antibiotic alternatives and the enhanced implementation of vaccination and biosecurity are promising management approaches to cut down the consumption of antibiotics during swine production. Through the comparison of different biological treatment technologies for removing A&H in SW, membrane-based bioprocesses have relatively higher and more stable removal efficiencies. Whereas, the combined system of bioprocesses and AOPs is expected to be a promising technology for elimination and mineralization of A&H in swine wastewater. Further study on this system is therefore necessary.
Choi, Y, Naidu, G, Lee, S & Vigneswaran, S 2020, 'Recovery of sodium sulfate from seawater brine using fractional submerged membrane distillation crystallizer', Chemosphere, vol. 238.
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© 2019 Elsevier Ltd Seawater reverse osmosis (SWRO) brine contain many valuable resources. In this study, fractional-submerged membrane distillation crystallizer (F-SMDC) was used to recover sodium sulfate (Na2SO4) from SWRO brine. The concentration/temperature gradient (CG/TG) in the reactor enhanced water recovery utilizing MD and Na2SO4 crystallization via a crystallizer. Crystals were not obtained at the bottom section of the F-SMDC due to: firstly, calcium sulfate crystallization occurring on the membrane surface; and secondly, low temperature-sensitivity solubility component such as NaCl exerting a negative influence. In order to obtain supersaturation, a sulfate-rich scenario was created in the reactor through the addition of the following three components: Na2SO4, MgSO4 and (NH4)2SO4. When Na2SO4 and MgSO4 were added, a larger concentration was observed at the top section, resulting in a low concentration gradient (CG) ratio, i.e. around 1.7. Conversely, the addition of (NH4)2SO4 achieved faster Na2SO4 crystallization (VCF 1.42) at the bottom section with a greater CG ratio of more than 2.0. Total water recovery ratio of 72% and 223.73 g Na2SO4 crystals were successfully extracted from simulated SWRO brine using laboratory scale F-SMDC.
Collins, S, Boyd, PW & Doblin, MA 2020, 'Evolution, Microbes, and Changing Ocean Conditions', ANNUAL REVIEW OF MARINE SCIENCE, VOL 12, vol. 12, pp. 181-208.
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Cui, Z, Hao Ngo, H, Cheng, Z, Zhang, H, Guo, W, Meng, X, Jia, H & Wang, J 2020, 'Hysteresis effect on backwashing process in a submerged hollow fiber membrane bioreactor (MBR) applied to membrane fouling mitigation.', Bioresource technology, vol. 300, pp. 122710-122710.
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Hysteresis effect on backwashing in a submerged MBR was investigated with dead-end hollow fiber membranes. The out-of-step changes in TMP and flux is the real hysteresis effect which is common but easily overlooked. Methods of visualization and ultrasonic spectrum analysis were implemented. The results showed that fouling layer is just the culprit of hysteresis effect. Fouling level and fiber length were determined as two key factors that affect hysteresis effect by data and model derivation. Moreover, a hysteresis evaluation index "τbw" is proposed to quantify the result of TMP vs time. The relationship between influence factors and "τbw" is interactive. A linear relationship between fouling level and "τbw" was found as well as an extreme value between fiber length and "τbw". A lower fouling level (lower backwashing flow) and optimal backwashing duration will be helpful for an effective backwashing no matter for membrane fouling control or energy cost reduce.
Dang, LC, Dang, CC & Khabbaz, H 2020, 'Modelling of columns and fibre reinforced load transfer platform supported embankments', Proceedings of the Institution of Civil Engineers - Ground Improvement.
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This study proposes a novel ground modification technique utilising fibre reinforced load transfer platform (FRLTP) and deep cement mixing (DCM) columns supported (CS) embankment constructed over soft soils. An equivalent two-dimensional finite element model was developed to simulate the full geometry of a CS embankment reinforced without or with an FRLTP. A series of numerical analyses was firstly conducted on the proposed model for different improvement depths to assess the effectiveness of the introduction of FRLTP into the CS embankment system in terms of total and differential settlements, stress transfer mechanism and lateral displacement with depth. Subsequently, another extensive parametric study was conducted to further investigate the influence of the FRLTP key parameters including elastic deformation modulus, shear strength properties, and tensile strength on the embankment performance during construction and consolidation time. The numerical results show that the embankment with FRLTP can effectively diminish the total settlement and the lateral deformation of the embankment, meanwhile improve the stress concentration ratio and the embankment stability to a great extent. The findings of the extensive parametric study indicate that the FRLTP shear strength properties appear to be the most influence factors to be considered in the design procedure of a target CS-FRLTP-embankment system.
Do, MH, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Liu, Y, Varjani, S & Kumar, M 2020, 'Microbial fuel cell-based biosensor for online monitoring wastewater quality: A critical review.', The Science of the total environment, vol. 712, pp. 135612-135612.
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Recently, the application of the microbial fuel cell (MFC)-based biosensor for rapid and real-time monitoring wastewater quality is very innovative due to its simple compact design, disposability, and cost-effectiveness. This review represents recent advances in this emerging technology for the management of wastewater quality, where the emphasis is on biochemical oxygen demand, toxicity, and other environmental applications. In addition, the main challenges of this technology are discussed, followed by proposing possible solutions to those challenges based on the existing knowledge of detection principles and signal processing. Potential future research of MFC-based biosensor has been demonstrated in this review.
Doan, S & Fatahi, B 2020, 'Analytical solution for free strain consolidation of stone column-reinforced soft ground considering spatial variation of total stress and drain resistance', COMPUTERS AND GEOTECHNICS, vol. 118.
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Dong, Y & Fatahi, B 2020, 'Discrete element simulation of cavity expansion in lightly cemented sands considering cementation degradation', Computers and Geotechnics, vol. 124.
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© 2020 Elsevier Ltd This study aims to investigate the influence of cementation on the stress-strain and strength characteristics of soil during cavity expansion in lightly cemented sand deposit using three-dimensional discrete element simulations. Contact models, simulating the cementation effects of bonded clumps and capturing the interlocking effects between discrete sand particles, are incorporated to mimic the cemented sands with various cement contents. The microscopic parameters are calibrated and validated against existing experimental results. Real scale cylindrical cavity expansion models starting from zero initial cavity radius with different levels of cementation are developed, and each proposed model consists of 150,000 particles with boundary conditions carefully selected to reproduce the realistic scenario. The embedded scripting is utilised to precisely measure both the local and global stress–strain variations, and record and analyse the cementation bond breakage during the cavity expansion process. The results confirm that the cementation enhances the material strength through the increase in cohesion and tensile strength at the contacting interfaces, whereas the friction angle is not altered notably. Hence, the failure envelope of the cemented sand gradually merges with the critical state line due to the cementation degradation, particularly at a high confining pressure. It was found that the failure mode of the lightly cemented sand adopted in this study, was mainly controlled by the shear rather than tensile strength at the contacting interfaces. Referring to the numerical predictions it is evident that the zone with significant cementation degradation due to the cavity expansion extends as far as 4af for all cemented specimens (af being the final cavity radius). In addition, specimens with higher cement content experience a more pronounced dilation at the internal cavity wall, while an inverse trend is captured at a greater radial distance. ...
Dong, Y, Fatahi, B & Khabbaz, H 2020, 'Three dimensional discrete element simulation of cylindrical cavity expansion from zero initial radius in sand', COMPUTERS AND GEOTECHNICS, vol. 117.
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Dorji, P, Kim, DI, Hong, S, Phuntsho, S & Shon, HK 2020, 'Pilot-scale membrane capacitive deionisation for effective bromide removal and high water recovery in seawater desalination', DESALINATION, vol. 479.
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Fabris, M, Abbriano, RM, Pernice, M, Sutherland, DL, Commault, AS, Hall, CC, Labeeuw, L, McCauley, J, Kuzhiuparambil, U, Ray, P, Kahlke, T & Ralph, PJ 2020, 'Emerging Technologies in Algal Biotechnology: Toward the Establishment of a Sustainable, Algae-Based Bioeconomy', FRONTIERS IN PLANT SCIENCE, vol. 11.
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Fabris, M, George, J, Kuzhiumparambil, U, Lawson, CA, Jaramillo-Madrid, AC, Abbriano, RM, Vickers, CE & Ralph, P 2020, 'Extrachromosomal Genetic Engineering of the Marine Diatom Phaeodactylum tricornutum Enables the Heterologous Production of Monoterpenoids', ACS SYNTHETIC BIOLOGY, vol. 9, no. 3, pp. 598-612.
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Fang, C, Rajabzadeh, S, Zhang, P, Liu, W, Kato, N, Shon, HK & Matsuyama, H 2020, 'Controlling spherulitic structures at surface and sub-layer of hollow fiber membranes prepared using nucleation agents via triple-orifice spinneret in TIPS process', Journal of Membrane Science, vol. 609, pp. 118229-118229.
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Fatahi, B, Huang, B, Yeganeh, N, Terzaghi, S & Banerjee, S 2020, 'Three-Dimensional Simulation of Seismic Slope-Foundation-Structure Interaction for Buildings Near Shallow Slopes', INTERNATIONAL JOURNAL OF GEOMECHANICS, vol. 20, no. 1.
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Gao, P, Huang, Z & Yu, H 2020, 'Exploration of the Dehydrogenation Pathways of Ammonia Diborane and Diammoniate of Diborane by Molecular Dynamics Simulations Using Reactive Force Fields', JOURNAL OF PHYSICAL CHEMISTRY A, vol. 124, no. 9, pp. 1698-1704.
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García-Rincón, J, Gatsios, E, Rayner, JL, McLaughlan, RG & Davis, GB 2020, 'Laser-induced fluorescence logging as a high-resolution characterisation tool to assess LNAPL mobility', Science of the Total Environment, vol. 725.
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© 2020 High-resolution characterisation tools such as Laser-Induced Fluorescence (LIF) logging represent a step forward towards a more effective management of sites contaminated by light non-aqueous phase liquid (LNAPL) petroleum hydrocarbons. In this paper, the applicability of LIF response as an indicator of LNAPL mobility at one site with an unconsolidated aquifer was investigated. LIF profiles were logged adjacent to twin coring locations and wells with LNAPL transmissivity (Tn) measurements in a heterogeneous gasoline contaminated site in Western Australia. LIF response was correlated to Tn to a greater extent than LNAPL saturation (Sn) measurements from coring. In particular, LIF signal maxima were a better indicator of Tn than the integral LIF signal. Furthermore, LIF allowed rapid identification of areas with long-term near-immobile LNAPL (entrapped and residual) because of the multi-wavelength waveforms associated with distinct subsurface characteristics. It was also demonstrated that the delineation of presumably less-mobile intervals could be enhanced by using the relative LIF response in the 350 nm wavelength channel. Thus, this work gave evidence that LIF logging provides valuable information about LNAPL distribution and mobility in commonly found subsurface settings, despite generally poor correlations with Sn measurements. LIF probes can be successfully used to guide the installation and application of more costly conventional methods in addition to the development of existing site models.
Ghobadi, R, Altaee, A, Zhou, JL, McLean, P & Yadav, S 2020, 'Copper removal from contaminated soil through electrokinetic process with reactive filter media', Chemosphere, vol. 252.
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© 2020 Elsevier Ltd Electrokinetic (EK) remediation has been used in the removal of metal ions from contaminated soil. This study focused on integrating the EK technique with different reactive filter media (RFM) of activated carbon (AC) and biochar (BC) for the first time without adding chemicals to facilitate the removal of copper ions from the contaminated kaolinite soil. Tests based on EK, EK coupled with AC (EK-AC), and EK combined with BC (EK-BC) were performed under an electric potential of 10 V, and the overall removal efficiency of copper ions decreased as EK-BC > EK-AC > EK. The results show that 27% of copper in the soil was captured by BC, compared with only 10% by AC. Additional EK-BC test performed under a constant current (20 mA) revealed that the acid front swept across the soil, resulting in 70.6–95.0% copper removal from soil sections 4 to 1 close to the anode region with more copper accumulation in section 5. Similar to the EK-BC test under a fixed voltage, 26% of copper in the soil was captured by BC during EK-BC treatment under a constant current although with a higher energy consumption. Moreover, RFM was regenerated by flushing with an acid solution, achieving 99.3% of copper recovery in BC and 78.4% in AC. Although the permeability of AC-RFM was higher than that of BC-RFM, copper contaminant was more easily leached out from the BC-RFM. The findings demonstrated the feasibility of contaminant entrapment in BC-RFM and recovery by acid leaching, with potential for sustainable soil remediation.
Hao, Q, Jia, G, Wei, W, Vinu, A, Wang, Y, Arandiyan, H & Ni, BJ 2020, 'Graphitic carbon nitride with different dimensionalities for energy and environmental applications', Nano Research, vol. 13, no. 1, pp. 18-37.
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© 2019, Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature. As a metal-free semiconductor, graphitic carbon nitride (g-C3N4) has received extensive attention due to its high stability, nontoxicity, facile and low-cost synthesis, appropriate band gap in the visible spectral range and wide availability of resources. The dimensions of g-C3N4 can influence the regime of the confinement of electrons, and consequently, g-C3N4 with various dimensionalities shows different properties, making them available for many stimulating applications. Although there are some reviews focusing on the synthesis strategy and applications of g-C3N4, there is still a lack of comprehensive review that systemically summarises the synthesis and application of different dimensions of g-C3N4, which can provide an important theoretical and practical basis for the development of g-C3N4 with different dimensionalities and maximises their potential in diverse applications. By reviewing the latest progress of g-C3N4 studies, we aim to summarise the preparation of g-C3N4 with different dimensionalities using various structural engineering strategies, discuss the fundamental bottlenecks of currently existing methods and their solution strategies, and explore their applications in energy and environmental applications. Furthermore, it also puts forward the views on the future research direction of these unique materials. [Figure not available: see fulltext.].
Hao, Q, Liu, C, Jia, G, Wang, Y, Arandiyan, H, Wei, W & Ni, B-J 2020, 'Catalytic reduction of nitrogen to produce ammonia by bismuth-based catalysts: state of the art and future prospects', Materials Horizons.
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This review provides an up-to-date review on Bi-based nitrogen-fixation materials and future directions for the development of new Bi-based nitrogen-fixation materials under ambient conditions.
Hao, Q, Xie, C, Huang, Y, Chen, D, Liu, Y, Wei, W & Ni, B-J 2020, 'Accelerated separation of photogenerated charge carriers and enhanced photocatalytic performance of g-C3N4 by Bi2S3 nanoparticles', CHINESE JOURNAL OF CATALYSIS, vol. 41, no. 2, pp. 249-258.
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Hien, NT, Lan, HN, Huu, TV, Thi, DN, Thi, HVN, Thi, HHC, Tien, VN, Van, TT, Xuan, HV & Aziz, KHH 2020, 'Heterogeneous catalyst ozonation of Direct Black 22 from aqueous solution in the presence of metal slags originating from industrial solid wastes', SEPARATION AND PURIFICATION TECHNOLOGY, vol. 233.
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Hoang, LP, Nguyen, TMP, Van, HT, Hoang, TKD, Vu, XH, Nguyen, TV & Ca, NX 2020, 'Cr(VI) Removal from Aqueous Solution Using a Magnetite Snail Shell', WATER AIR AND SOIL POLLUTION, vol. 231, no. 1.
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Hossain, SM, Park, H, Kang, HJ, Kim, JB, Tijing, L, Rhee, I, Jun, YS, Shon, HK & Kim, JH 2020, 'Preparation and characterization of photoactive anatase TiO2 from algae bloomed surface water', Catalysts, vol. 10, no. 4.
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© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The purpose of the study was to effectively treat algae bloomed water while using a Ti-based coagulant (TiCl4) and recover photoactive novel anatase TiO2 from the flocculated sludge. Conventional jar tests were conducted in order to evaluate the coagulation efficiency, and TiCl4 was found superior compared to commercially available poly aluminum chloride (PAC). At a dose of 0.3 g Ti/L, the removal rate of turbidity, chemical oxygen demand (COD), and total phosphorus (TP) were measured as 99.8%, 66.7%, and 96.9%, respectively. Besides, TiO2 nanoparticles (NPs) were recovered from the flocculated sludge and scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and X-ray diffraction (XRD) analysis confirmed the presence of only anatase phase. The recovered TiO2 was found to be effective in removing gaseous CH3CHO and NOx under UV-A lamp at a light intensity of 10 W/m2. Additionally, the TiO2 mixed mortar blocks that were prepared in this study successfully removed atmospheric nitrogen oxide (NOx) under UV irradiance. This study is one of the first to prepare anatase TiO2 from flocculated algal sludge and it showed promising results. Further research on this novel TiO2 concerning internal chemical bonds and shift in the absorbance spectrum could explore several practical implications.
Hossain, SMG & McLaughlan, RG 2020, 'Non-equilibrium 2, 4-DCP uptake onto pine chips from aqueous solutions', ENVIRONMENTAL TECHNOLOGY.
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Hosseinzadeh, A, Baziar, M, Alidadi, H, Zhou, JL, Altaee, A, Najafpoor, AA & Jafarpour, S 2020, 'Application of artificial neural network and multiple linear regression in modeling nutrient recovery in vermicompost under different conditions', BIORESOURCE TECHNOLOGY, vol. 303.
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Hosseinzadeh, A, Zhou, JL, Altaee, A, Baziar, M & Li, X 2020, 'Modeling water flux in osmotic membrane bioreactor by adaptive network-based fuzzy inference system and artificial neural network', Bioresource Technology, vol. 310.
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© 2020 Elsevier Ltd Osmotic Membrane Bioreactor (OMBR) is an emerging technology for wastewater treatment with membrane fouling as a major challenge. This study aims to develop Adaptive Network-based Fuzzy Inference System (ANFIS) and Artificial Neural Network (ANN) models in simulating and predicting water flux in OMBR. Mixed liquor suspended solid (MLSS), electrical conductivity (EC) and dissolved oxygen (DO) were used as model inputs. Good prediction was demonstrated by both ANFIS models with R2 of 0.9755 and 0.9861, and ANN models with R2 of 0.9404 and 0.9817, for thin film composite (TFC) and cellulose triacetate (CTA) membranes, respectively. The root mean square error for TFC (0.2527) and CTA (0.1230) in ANFIS models was lower than in ANN models at 0.4049 and 0.1449. Sensitivity analysis showed that EC was the most important factor for both TFC and CTA membranes in ANN models, while EC (TFC) and MLSS (CTA) are key parameters in ANFIS models.
Hou, J, Li, B, Tong, Y, Ma, L, Ball, J, Luo, H, Liang, Q & Xia, J 2020, 'Cause analysis for a new type of devastating flash flood', Hydrology Research, vol. 51, no. 1, pp. 1-16.
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Abstract
This work introduces an unprecedented flash flood that resulted in nine casualties in Shimen Valley, China, 2015. Through field survey and numerical simulation the causes of the disaster are systematically analyzed, finding that the intense storm, terrain features, and the large woody debris (LWD) played important roles. The intense storm induced fast runoff and, in turn, high discharges as a result of the steep catchment surfaces and channels. The flood flushed LWD and boulders downstream until blockage occurred in a contraction section, forming a debris lake. When the debris dam broke, a dam break wave rapidly propagated to the valley mouth, washing people away. After considering the disaster-inducing factors, measures for preventing similar floods are proposed. The analysis presented herein should help others manage flash floods in mountain areas.
Hu, X, Zhang, X, Ngo, HH, Guo, W, Wen, H, Li, C, Zhang, Y & Ma, C 2020, 'Comparison study on the ammonium adsorption of the biochars derived from different kinds of fruit peel.', The Science of the total environment, pp. 135544-135544.
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Application of biochars to remove inorganic nitrogen (NH4+, NO2-, NH3, NO, NO2, N2O) from wastewater and agricultural fields has gained a significant interest. This study aims to investigate the relationship between ammonium sorption and physicochemical properties of biochars derived from different kinds of fruit peel. Biochars from three species of fruit peel (orange, pineapple and pitaya) were prepared at 300, 400, 500 and 600 °C with the residence time of 2 h and 4 h. Their characteristics and sorption for ammonium was evaluated. The results show a clear effect of pyrolysis conditions on physicochemical properties of biochars, including elemental composition, functional groups and pH. The maximum NH4+ adsorption capacities were associated with biochars of orange peel (4.71 mg/g) and pineapple peel (5.60 mg/g) produced at 300 °C for 2 h. The maximum NH4+ adsorption capacity of the pitaya peel biochar produced at 400 °C for 2 h was 2.65 mg/g. For all feedstocks, biochars produced at low temperatures showed better NH4+ adsorption capacity. It was found that biochars had better adsorption efficiency on ammonium at a pH of 9. Adsorption kinetics of ammonium on biochars followed the pseudo-second-order kinetic model while Langmuir isotherm model could well simulate the adsorption behavior of ammonium on biochars. The adsorption mechanism of ammonium on biochars predominantly involved surface complexation, cation exchange and electrostatic attraction. Conclusively, the fruit peel-derived biochars can be used as an alternative to conventional sorbents in water treatment.
Huang, Q-S, Wu, W, Wei, W, Song, L, Sun, J & Ni, B-J 2020, 'Highly-efficient Pb2+ removal from water by novel K2W4O13 nanowires: Performance, mechanisms and DFT calculation', CHEMICAL ENGINEERING JOURNAL, vol. 381.
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Huang, Y, Ng, ECY, Surawski, NC, Yam, YS, Mok, WC, Liu, CH, Zhou, JL, Organ, B & Chan, EFC 2020, 'Large eddy simulation of vehicle emissions dispersion: Implications for on-road remote sensing measurements', Environmental Pollution, vol. 259.
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© 2020 Elsevier Ltd On-road remote sensing technology measures the concentration ratios of pollutants over CO2 in the exhaust plume in half a second when a vehicle passes by a measurement site, providing a rapid, non-intrusive and economic tool for vehicle emissions monitoring and control. A key assumption in such measurement is that the emission ratios are constant for a given plume. However, there is a lack of study on this assumption, whose validity could be affected by a number of factors, especially the engine operating conditions and turbulence. To guide the development of the next-generation remote sensing system, this study is conducted to investigate the effects of various factors on the emissions dispersion process in the vehicle near-wake region and their effects on remote sensing measurement. The emissions dispersion process is modelled using Large Eddy Simulation (LES). The studied factors include the height of the remote sensing beam, vehicle speed, acceleration and side wind. The results show that the measurable CO2 and NO exhaust plumes are relatively short at 30 km/h cruising speed, indicating that a large percentage of remote sensing readings within the measurement duration (0.5 s) are below the sensor detection limit which would distort the derived emission ratio. In addition, the valid measurement region of NO/CO2 emission ratio is even shorter than the measurable plume and is at the tailpipe height. The effect of vehicle speed (30–90 km/h) on the measurable plume length is insignificant. Under deceleration condition, the length of the valid NO/CO2 measurement region is shorter than under cruising and acceleration conditions. Side winds from the far-tailpipe direction have a significant effect on remote sensing measurements. The implications of these findings are discussed and possible solutions to improve the accuracy of remote sensing measurement are proposed.
Huang, Z, Wang, S, Dewhurst, RD, Ignat'ev, NV, Finze, M & Braunschweig, H 2020, 'Boron: Its role in energy related research and applications.', Angewandte Chemie (International ed. in English).
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Boron's uniqueposition in the periodic table, i.e. at the apex of the line separating metals and nonmetals, makes it highly versatile in chemical reactions and applications. Contemporary demand for renewable and clean energy and energy-efficient products has seen boron playing key roles in energy-related research, from activating and synthesizing energy-rich small molecules, to storing chemical and electrical energy, to converting electrical energy to light. These applications are fundamentally associated with boron's unique characteristics, such as its electron-deficiency and the availability of an unoccupied p orbital, which allow the formation of a myriad of compounds with great tunability in chemical and physical properties. For example, boron's ability to achieve a full octet of electrons with four covalent bonds and a negative charge has led to the synthesis of a wide variety of borate anions of high chemical and electrochemical stability, in particular the useful family of weakly coordinating anions. This review summarizes recent advances in the study of boron compounds for energy-related research and applications, driven by modern demands and enabled by breakthroughs in the synthesis and understanding of boron chemistry.
Hughes, DJ, Crosswell, JR, Doblin, MA, Oxborough, K, Ralph, PJ, Varkey, D & Suggett, DJ 2020, 'Dynamic variability of the phytoplankton electron requirement for carbon fixation in eastern Australian waters', Journal of Marine Systems, vol. 202.
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© 2019 Elsevier B.V. Fast Repetition Rate fluorometry (FRRf) generates high-resolution measures of phytoplankton primary productivity as electron transport rates (ETRs). How ETRs scale to corresponding inorganic carbon (C) uptake rates (the so-called electron requirement for carbon fixation, Φe,C), inherently describes the extent and effectiveness with which absorbed light energy drives C-fixation. However, it remains unclear whether and how Φe,C follows predictable patterns for oceanographic datasets spanning physically dynamic, and complex, environmental gradients. We utilise a unique high-throughput approach, coupling ETRs and 14C-incubations to produce a semi-continuous dataset of Φe,C (n = 80), predominantly from surface waters, along the Australian coast (Brisbane to the Tasman Sea), including the East Australian Current (EAC). Environmental conditions along this transect could be generally grouped into cooler, more nutrient-rich waters dominated by larger size-fractionated Chl-a (>10 μm) versus warmer nutrient-poorer waters dominated by smaller size-fractionated Chl-a (<2 μm). Whilst Φe,C was higher for warmer water samples, environmental conditions alone explained <20% variance of Φe,C, and changes in predominant size-fraction(s) distributions of Chl-a (biomass) failed to explain variance of Φe,C. Instead, normalised Stern-Volmer non-photochemical quenching (NPQNSV = F0′/Fv′) was a better predictor of Φe,C, explaining ~55% of observed variability. NPQNSV is a physiological descriptor that accounts for changes in both long-term driven acclimation in non-radiative decay, and quasi-instantaneous PSII downregulation, and thus may prove a useful predictor of Φe,C across physically-dynamic regimes, provided the slope describing their relationship is predictable. We also consider recent advances in fluorescence-based corrections to evaluate the potential role of baseline fluorescence (Fb) in contributing to overestimation of Φe,C and the correlation between Φe,C...
Ibrar, I, Altaee, A, Zhou, JL, Naji, O & Khanafer, D 2020, 'Challenges and potentials of forward osmosis process in the treatment of wastewater', Critical Reviews in Environmental Science and Technology, pp. 1-45.
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Jaramillo-Madrid, AC, Ashworth, J & Ralph, PJ 2020, 'Levels of diatom minor sterols respond to changes in temperature and salinity', Journal of Marine Science and Engineering, vol. 8, no. 2.
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© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Diatoms are a broadly distributed and evolutionarily diversified group of microalgae that produce a diverse range of sterol compounds. Sterols are triterpenoids that play essential roles in membrane-related processes in eukaryotic cells. Some sterol compounds possess bioactivities that promote human health and are currently used as nutraceuticals. The relationship between sterol diversity in diatoms and their acclimation to different environments is not well understood. In this study, we investigated the occurrence of different sterol types across twelve diatom species, as well as the effect of temperature reduction and changes in salinity on the sterol contents of three model diatom species. In the diatoms Thalassiosira pseudonana, Phaeodactylum tricornutum and Chaetoceros muelleri, we found that changes in the relative contents of minor sterols accompanied shifts in temperature and salinity. This may be indicative of acquired adaptive traits in diatom metabolism.
Jaramillo-Madrid, AC, Ashworth, J, Fabris, M & Ralph, PJ 2020, 'The unique sterol biosynthesis pathway of three model diatoms consists of a conserved core and diversified endpoints', Algal Research, vol. 48.
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© 2020 Diatoms produce a wide diversity of sterols among different species, the biosynthesis and conservation of which is not yet fully understood. To investigate the conservation and divergence of sterol biosynthesis pathways among diatoms, we performed comparative metabolic profiling and transcriptomics for a centric diatom (Thalassiosira pseudonana), a pennate diatom (Phaeodactylum tricornutum) and a chaetocerid (Chaetoceros muelleri) in response to inhibitors of enzymes involved in sterol biosynthesis. These three model diatoms, which are representative of distinct clades, share a unique core phytosterol biosynthesis pathway that relies on a terbinafine-insensitive alternative squalene epoxidase and the cyclization of 2,3-epoxysqualene into cycloartenol by a conserved oxidosqualene cyclase. Lineage-specific divergence in the synthesis of sterol precursors was found in the species analyzed. Cholesterol synthesis in diatoms seems to occur via cycloartenol rather than lanosterol. The diversification of natural sterols produced by each species appears to occur downstream of all experimentally targeted enzymes, suggesting adaptive specialization in terminal synthesis pathways.
Ji, M, Hu, Z, Hou, C, Liu, H, Ngo, HH, Guo, W, Lu, S & Zhang, J 2020, 'New insights for enhancing the performance of constructed wetlands at low temperatures', Bioresource Technology, vol. 301.
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© 2019 Elsevier Ltd Constructed wetlands (CWs) have been widely utilized for various types of wastewater treatment due to their merits, including high cost-effectiveness and easy operation. However, a few intrinsic drawbacks have always restricted their application and long-term stability, especially their weak performance at temperatures under 10 °C (low temperatures) due to the deterioration of microbial assimilation and plant uptake processes. The existing modifications to improve CWs performance from the direct optimization of internal components to the indirect adjunction of external resources promoted the wastewater treatment efficiency to a certain degree, but the sustainability and sufficiency of pollutants removal remains a challenge. With the goal of optimizing CW components, the integrity of the CW ecosystem and the removal of emerging pollutants, future directions for research should include radiation plant breeding, improvements to CW ecosystems, and the combination or integration of certain treatment processes with CWs to enhance wastewater treatment effects at low temperatures.
Khanzada, NK, Farid, MU, Kharraz, JA, Choi, J, Tang, CY, Nghiem, LD, Jang, A & An, AK 2020, 'Removal of organic micropollutants using advanced membrane-based water and wastewater treatment: A review', Journal of Membrane Science, vol. 598.
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© 2019 Elsevier B.V. The rising consumption of pharmaceuticals, personal care products, and endocrine disruptive compounds for healthcare purposes and improving living standards has resulted in the widespread occurrence of organic micropollutants (MPs) in water and wastewater. Conventional water/wastewater treatment plants are faced with inherent limitations in tackling these compounds, leading to difficulties in the provision of secure and safe water supplies. In this context, membrane technology has been found to be a promising method for resolving this emerging concern. To ensure the suitability of membrane-based treatment processes in full-scale applications, we first need to develop a better understanding of the behavior of MPs and the mechanisms behind their removal using advanced membrane technologies. This review provides a thorough overview of the advanced membrane-based treatment methods available for the effective removal of MPs, including reverse osmosis, nanofiltration, ultrafiltration, forward osmosis, and membrane distillation.
Kim, D, Nguyen, LN & Oh, S 2020, 'Ecological impact of the antibiotic ciprofloxacin on microbial community of aerobic activated sludge.', Environmental geochemistry and health.
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This study investigated the effects and fate of the antibiotic ciprofloxacin (CIP) at environmentally relevant levels (50-500 µg/L) in activated sludge (AS) microbial communities under aerobic conditions. Exposure to 500 µg/L of CIP decreased species diversity by about 20% and significantly altered the phylogenetic structure of AS communities compared to those of control communities (no CIP exposure), while there were no significant changes upon exposure to 50 µg/L of CIP. Analysis of community composition revealed that exposure to 500 µg/L of CIP significantly reduced the relative abundance of Rhodobacteraceae and Nakamurellaceae by more than tenfold. These species frequently occur in AS communities across many full-scale wastewater treatment plants and are involved in key ecosystem functions (i.e., organic matter and nitrogen removal). Our analyses showed that 50-500 µg/L CIP was poorly removed in AS (about 20% removal), implying that the majority of CIP from AS processes may be released with either their effluents or waste sludge. We therefore strongly recommend further research on CIP residuals and/or post-treatment processes (e.g., anaerobic digestion) for waste streams that may cause ecological risks in receiving water bodies.
Kim, DI, Gonzales, RR, Dorji, P, Gwak, G, Phuntsho, S, Hong, S & Shon, H 2020, 'Efficient recovery of nitrate from municipal wastewater via MCDI using anion-exchange polymer coated electrode embedded with nitrate selective resin', DESALINATION, vol. 484.
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Kulk, G, Platt, T, Dingle, J, Jackson, T, Jönsson, BF, Bouman, HA, Babin, M, Brewin, RJW, Doblin, M, Estrada, M, Figueiras, FG, Furuya, K, González-Benítez, N, Gudfinnsson, HG, Gudmundsson, K, Huang, B, Isada, T, Kovač, Ž, Lutz, VA, Marañón, E, Raman, M, Richardson, K, Rozema, PD, van de Poll, WH, Segura, V, Tilstone, GH, Uitz, J, van Dongen-Vogels, V, Yoshikawa, T & Sathyendranath, S 2020, 'Primary production, an index of climate change in the ocean: Satellite-based estimates over two decades', Remote Sensing, vol. 12, no. 5.
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© 2020 by the authors. Primary production by marine phytoplankton is one of the largest fluxes of carbon on our planet. In the past few decades, considerable progress has been made in estimating global primary production at high spatial and temporal scales by combining in situ measurements of primary production with remote-sensing observations of phytoplankton biomass. One of the major challenges in this approach lies in the assignment of the appropriate model parameters that define the photosynthetic response of phytoplankton to the light field. In the present study, a global database of in situ measurements of photosynthesis versus irradiance (P-I) parameters and a 20-year record of climate quality satellite observations were used to assess global primary production and its variability with seasons and locations as well as between years. In addition, the sensitivity of the computed primary production to potential changes in the photosynthetic response of phytoplankton cells under changing environmental conditions was investigated. Global annual primary production varied from 38.8 to 42.1 Gt C yr-1 over the period of 1998-2018. Inter-annual changes in global primary production did not follow a linear trend, and regional differences in the magnitude and direction of change in primary production were observed. Trends in primary production followed directly from changes in chlorophyll-a and were related to changes in the physico-chemical conditions of the water column due to inter-annual and multidecadal climate oscillations. Moreover, the sensitivity analysis in which P-I parameters were adjusted by ±1 standard deviation showed the importance of accurately assigning photosynthetic parameters in global and regional calculations of primary production. The assimilation number of the P-I curve showed strong relationships with environmental variables such as temperature and had a practically one-to-one relationship with the magnitude of change in primary production. In...
Lee, D, Woo, YC, Park, KH, Phuntsho, S, Tijing, LD, Yao, M, Shim, WG & Shon, HK 2020, 'Polyvinylidene fluoride phase design by two-dimensional boron nitride enables enhanced performance and stability for seawater desalination', Journal of Membrane Science, vol. 598.
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© 2019 The instability of polyvinylidene fluoride (PVDF) membranes in membrane distillation (MD) for seawater desalination is still a problem, despite the tremendous effort expended to resolve this issue. Here, a simple and feasible approach for improving desalination performance through the incorporation of two-dimensional boron nitride nanosheets (BNNSs) in polyvinylidene fluoride-co-hexafluoropropene (PVDF-co-HFP) electrospun nanofiber membrane (BNs-PH) is proposed as well as demonstrate its origin for fundamental understanding. The BNs-PH membrane exhibits a stable water vapor flux (18 LMH) and superior salt rejection (99.99%), even after operation for 280 h (commercial PVDF: steep decay within 28 h; neat PH: wetting within 4 h). From structural/chemical analyses, the BNNSs play a crucial role in forming favorable phases of the PH polymer crystal structure, inducing a superhydrophobic surface with greater nanoporosity and higher heterogeneity as well as enhanced mechanical properties (increase of UTS: 13.4%; modulus: 1.2%) for long-term operation. Theoretical modeling results of an air-gap MD system are consistent with our experimental results. The approach introduced in this study can be applied to other desalination systems to boost various water treatment applications.
Li, L, Song, K, Yeerken, S, Geng, S, Liu, D, Dai, Z, Xie, F, Zhou, X & Wang, Q 2020, 'Effect evaluation of microplastics on activated sludge nitrification and denitrification', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 707.
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Li, X, Chen, L, Ji, Y, Li, M, Dong, B, Qian, G, Zhou, J & Dai, X 2020, 'Effects of chemical pretreatments on microplastic extraction in sewage sludge and their physicochemical characteristics.', Water research, vol. 171, pp. 115379-115379.
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Sewage sludge is a primary pathway for microplastics (MPs) entering into terrestrial ecosystems. However, a standardized method to analyze MP in sludge is lacking due to its high organic matter. This study investigated the extraction efficiency of six MPs in five solid matrices, i.e. sewage sludge, cattle manure, soil, sediment and silicon dioxide. Results show lower extraction efficiency of 87.2% for MPs in sludge compared with that in other matrices, especially polyethylene terephthalate (PET) (only 27.8%). The possible reason was that the presence of extracellular polymeric substances within the sludge hinders the MPs to float. Therefore, five protocols, i.e. hydrogen peroxide (H2O2), Fenton, nitric acid (HNO3), hydrochloric acid (HCl) and sodium hydroxide (NaOH) were used to pretreat the sludge and optimize the MP extraction. The sludge pretreated by H2O2, Fenton and 1 M of acids had higher MP extraction efficiency than the raw sludge due to higher extraction of the PET. The MP extraction efficiency in the sludge first increased, and subsequently decreased with the soluble chemical oxygen demand (SCOD) content, implying that moderate dissolution of sludge organic matter is beneficial to the MP extraction. Quantitative analysis of the changes in the MP physicochemical characteristics after the pretreatments indicated that polyamide (PA) and PET are not resistant to acid and alkali treatment, respectively. Principal component analysis shows that the effect of pretreatments on the MPs follows a decreasing sequence: alkali > high concentration of acids > low concentration of acids > H2O2 and Fenton. Additionally, the susceptibility of the MPs to the pretreatments follows a decreasing sequence: PET, PA and polymethyl methacrylate (PMMA) > polystyrene (PS) > polyethylene (PE) and polypropylene (PP). The findings supply novel insights into the effect of chemical pretreatments on MP extraction in sewage sludge.
Li, X, Ji, M, Nghiem, LD, Zhao, Y, Liu, D, Yang, Y, Wang, Q, Trinh, QT, Vo, DVN, Pham, VQ & Tran, NH 2020, 'A novel red mud adsorbent for phosphorus and diclofenac removal from wastewater', Journal of Molecular Liquids, vol. 303.
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© 2019 Elsevier B.V. The ubiquitous occurrence of nutrients (e.g. phosphorus) and micropollutants (e.g. pharmaceuticals and endocrine disrupting chemicals) in wastewater and urban stormwater runoff sources may cause adverse effects on aquatic ecosystems and human health. Therefore, the removal of these pollutants from wastewater, treated effluent, and urban stormwater runoff is critically needed. In this study, a novel modified red mud with polypyrrole (RM-PPy) was successfully synthesized with improved functional groups (–OH, –N=, –NH–, N+), specific area (SBET 102.24 m2/g), and mesopore structure (i.e. average pore diameter of 3.29 nm), which are assumed to enhance the adsorptive removal of diclofenac (DCF) and phosphorus (P) in aqueous solution. The measured maximum adsorption capacity of RM-PPy towards diclofenac (195 mg/g) in single adsorbate system was higher than that (115.7 mg/g) in the binary adsorbates system (i.e. in the presence of P), indicating that the presence of pollutants such as P in water hampered the adsorptive removal of DCF. The adsorption of DCF and P was largely dependent on solution pH values. Higher adsorptive removals of DCF and P were observed at acidic conditions (pH 2–5). Adsorption isotherm of DCF and P was better fitted to Freundlich model compared to Langmuir isotherm model, suggesting multilayer coverage. Adsorption of DCF onto RM-PPy might take place via anion exchange and electrostatic interactions. For P adsorption, apart from anion exchange and electrostatic interactions, the chemical precipitation via ligand exchange between P and hydroxyl (–OH) in RM-PPy can be considered as one of the main adsorption mechanisms. Further studies on the competitive adsorption of other anionic micropollutants at environmentally relevant concentrations (ng/L–μg/L) in water samples by RM-PPy are needed to evaluate the potential application of RM-PPy for the removal of other anionic micropollutants (i.e. antibiotics) in treated wastewater and s...
Li, Y, Wang, D, Yang, G, Yuan, X, Xu, Q, Yang, Q, Liu, Y, Wang, Q, Ni, B-J, Tang, W & Jiang, L 2020, 'Enhanced dewaterability of anaerobically digested sludge by in-situ free nitrous acid treatment', WATER RESEARCH, vol. 169.
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Li, Y, Zhu, Y, Wang, D, Yang, G, Pan, L, Wang, Q, Ni, BJ, Li, H, Yuan, X, Jiang, L & Tang, W 2020, 'Fe(II) catalyzing sodium percarbonate facilitates the dewaterability of waste activated sludge: Performance, mechanism, and implication', Water Research, vol. 174.
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© 2020 Elsevier Ltd In this work, Fe(II) catalyzing sodium percarbonate (Fe(II)/SPC) was managed to facilitate waste activated sludge (WAS) dewatering for the first time. The results showed that after WAS was treated by 20 mg/g total suspended solids (TSS) Fe(II) and 50 mg/g TSS SPC, the water content of sludge cake (WCSC) by press filtration and capillary suction time (CST) dropped from 90.8% ± 1.6% and 96.1 ± 4.0 s (the control) to 55.6% ± 1.4% and 30.1 ± 2.5 s, respectively. The mechanism investigations indicated that four intermediates or products (i.e., •OH, H2O2, Fe(II), and Fe(III)) generated in the Fe(II)/SPC process were responsible for the improved WAS dewaterability, and •OH and Fe(III) were the two major contributors. It was found that •OH collapsed and fragmented extracellular polymeric substances, damaged cell wall and permeabilized cytoplasmic membrane, and transformed conformation of the extracellular proteins secondary structure via both affecting the hydrogen bond maintaining α-helix and cracking disulfide bond in cysteine residues while Fe(III), the oxidization product of Fe(II), decreased the surface electronegativity and water-affinity surface areas of WAS flocs. As a result, the bound water release, flocculability, surface hydrophobicity, drain capability, and flowability of WAS flocs were strengthened whereas the compact surface structure, colloidal forces, network strength, gel-like structure, and apparent viscosity of WAS flocs were weakened. In addition, Fe(II)/SPC process also reduced the recalcitrant organics and fecal coliforms in sludge, which facilitated land application of dewatered sludge. The findings acquired in this work not only deepens our understanding of Fe(II)/SPC-involved WAS treatment process but also may guide engineers to develop both effective and promising strategies to better condition WAS for dewatering in the future.
Lim, S, Akther, N, Tran, VH, Bae, TH, Phuntsho, S, Merenda, A, Dumée, LF & Shon, HK 2020, 'Covalent organic framework incorporated outer-selective hollow fiber thin-film nanocomposite membranes for osmotically driven desalination', Desalination, vol. 485.
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© 2020 Elsevier B.V. In this study, new outer-selective hollow fiber (OSHF) thin film nanocomposite (TFN) forward osmosis (FO) membranes incorporated with amine-rich Schiff-based network (SNW-1) nanoparticles (NPs), a type of covalent organic frameworks (COFs), were developed by vacuum-assisted interfacial polymerization (VAIP). The SNW-1 NPs possess hydrophilic nature and porous internal structures, which are desirable for producing highly permeable and efficient FO membranes. SNW-1 NPs were conformally packed across the outer surface of the HF substrate by vacuum pressure applied during the VAIP process leading to defect-free coatings. Furthermore, covalent bonding between secondary amine (NH2−) groups across the SNW-1 network and remanent carboxylic groups present from the monomer used for the interfacial polymerization step supported the adhesion of SNW-1 NPs to the native poly(amide) layer present across the TFN membrane surface. As a result, SNW-1 loading at 0.001 wt% exhibited the best FO performance with enhanced water flux more than 23% of the pristine one (31.5 L m−2 h−1) and relatively low specific reverse solute flux (SRSF, Js/Jw) at 0.18 g L−1 using 1 M NaCl and DI water in series of TFN composite membranes. The optimum loading at 0.001 wt% was much lower than those in other home-made TFN membranes (normally above 0.05 wt%) due to the minimum loss of SNW-1 in the VAIP. Also, the TFN membrane offered excellent FO operation stability tested for 72 h. Such novel approach is promising to optimize FO processes for desalination and water treatment in the future.
Lim, S, Park, KH, Tran, VH, Akther, N, Phuntsho, S, Choi, JY & Shon, HK 2020, 'Size-controlled graphene oxide for highly permeable and fouling-resistant outer-selective hollow fiber thin-film composite membranes for forward osmosis', Journal of Membrane Science, vol. 609, pp. 118171-118171.
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Liu, X, He, D, Wu, Y, Xu, Q, Wang, D, Yang, Q, Liu, Y, Ni, BJ, Wang, Q & Li, X 2020, 'Freezing in the presence of nitrite pretreatment enhances hydrogen production from dark fermentation of waste activated sludge', Journal of Cleaner Production, vol. 248.
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© 2019 Elsevier Ltd Due to the poor biodegradability of released organics and the rapid consumption of hydrogen, hydrogen production from the untreated waste activated sludge (WAS) and/or inocula is still limited. In this study, it was found that the dark fermentative hydrogen production was largely enhanced from WAS pretreated by freezing in the presence of nitrite. With an increase of nitrite addition from 100 to 400 mg NO2−-N/L during freezing pretreatment (−5 °C for 4 h), the maximal hydrogen yield increased from 7.96 to 19.40 mL/g VS (volatile solids), which was 5.5–13.4 times of that in the control (without freezing and nitrite addition). Mechanism explorations revealed that the proposed pretreatment not only accelerated the disintegration of sludge but also promoted the proportion of biodegradable organics released, thereby provided more bio-available substrates for subsequent hydrogen production. Proposed pretreatment severely suppressed the sludge microorganisms responding to homoacetogenesis (−32.1%), methanogenesis (−58.4%), and sulfate-reducing process (−51.5%), inhibited the consumption of hydrogen. Moreover, there was more acetic and butyric (76% versus 57.5%) but less propionic acid (22.6% versus 13.4%) in this pretreated fermenter, which was in correspondence with the theory of fermentation type affecting hydrogen production. Long-term fermentation experiments indicated that the proposed pretreatment boosted the [FeFe]-hydrogenase activities while suppressed the activities of carbon monoxide dehydrogenase, coenzyme F420, and adenylyl sulfate reductase.
Liu, X, Huang, X, Wu, Y, Xu, Q, Du, M, Wang, D, Yang, Q, Liu, Y, Ni, BJ, Yang, G, Yang, F & Wang, Q 2020, 'Activation of nitrite by freezing process for anaerobic digestion enhancement of waste activated sludge: Performance and mechanisms', Chemical Engineering Journal, vol. 387.
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© 2020 Elsevier B.V. Nitrite-based pretreatment was demonstrated to effectively improve anaerobic digestion of waste activated sludge. It was found in this work that the freezing activated nitrite pretreatment could further enhance the performances. With the increase of nitrite addition from 0 to 600 mg NO2−-N/L during freezing process, the biochemical methane potential of pretreated-sludge gradually increased from 191.3 ± 8.0 to 233.2 ± 10.6 mL per gram volatile solid (VS), while only 178.6 ± 7.3 mL/g VS was obtained in the raw sludge. Mechanism explorations revealed that the freezing activated nitrite pretreatment remarkably facilitated the disintegration of sludge. Excitation emission matrix and fluorescence regional integration analyses further revealed that nitrite addition during freezing process promoted the proportion of biodegradable organics released, thereby providing more bio-available substrates for subsequent anaerobic digestion. Freezing condition induced reactive derivatives from nitrite (e.g., free nitrite acid, NO2[rad], N2O3) were assumed to be the major contributors to the enhanced sludge disintegration and recalcitrant organics (e.g., humic acid-like substances) degradation. It was also found that 600 mg NO2−-N/L addition activated by freezing pretreatment produced an anaerobically digested sludge with an improved dewaterability, as indicated by the decrease of the specific resistance to filterability and moisture content of dewatered cake. Moreover, 600 mg NO2−-N/L addition activated by freezing pretreatment and subsequent anaerobic digestion largely inactivated the pathogens to the levels below Class A biosolids requirements. Considering that nitrite can be in-situ produced in wastewater treatment plants through nitritation of the digestion liquid, this nitrite-based freezing process for sludge pretreatment was environmental-friendly and economically attractive.
Liu, Y, Luo, G, Ngo, HH, Guo, W & Zhang, S 2020, 'Advances in thermostable laccase and its current application in lignin-first biorefinery: A review.', Bioresource technology, pp. 122511-122511.
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As the most abundant aromatic polymers on the Earth, lignin has great potential to produce biofuels and aromatic chemicals due to their high carbon content and low oxygen content. Lignin-first biorefinery methods have attracted increasing attention recently for their high-value of aromatic chemicals, and high biofuels productivity from lignocellulosic wastes. Thermostable laccase has proven to be an excellent alternative catalyst in degrading lignin for its versatile catalytic abilities under industrial conditions and pollution-free by-products. Thermostable laccases can be found in native extreme environments or modified by biologically based technologies such as gene recombination expression and enzyme direct evolution. This review demonstrated thermostable laccases and their application in lignin degradation. Future research should focus more on the investigation of the reaction of thermostable laccases with lignin substrates.
Liu, Y, Ngo, HH, Guo, W, Wang, D, Peng, L, Wei, W & Ni, B-J 2020, 'Impact of coexistence of sludge flocs on nitrous oxide production in a granule-based nitrification system: A model-based evaluation', WATER RESEARCH, vol. 170.
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Liyanaarachchi, S, Jegatheesan, V, Shu, L, Shon, HK, Muthukumaran, S & Li, CQ 2020, 'Evaluating the Feasibility of Forward Osmosis in Diluting RO Concentrate Using Pretreatment Backwash Water.', Membranes, vol. 10, no. 3.
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Forward osmosis (FO) is an excellent membrane process to dilute seawater (SW) reverse osmosis (RO) concentrate for either to increase the water recovery or for safe disposal. However, the low fluxes through FO membranes as well the biofouling/scaling of FO membranes are bottlenecks of this process requiring larger membrane area and membranes with anti-fouling properties. This study evaluates the performance of hollow fibre and flat sheet membranes with respect to flux and biofouling. Ferric hydroxide sludge was used as impaired water mimicking the backwash water of a filter that is generally employed as pretreatment in a SWRO plant and RO concentrate was used as draw solution for the studies. Synthetic salts are also used as draw solutions to compare the flux produced. The study found that cellulose triacetate (CTA) flat sheet FO membrane produced higher flux (3-6 L m-2 h-1) compared to that produced by polyamide (PA) hollow fibre FO membrane (less than 2.5 L m-2 h-1) under the same experimental conditions. Therefore, long-term studies conducted on the flat sheet FO membranes showed that fouling due to ferric hydroxide sludge did not allow the water flux to increase more than 3.15 L m-2 h-1.
Loganathan, P, Gradzielski, M, Bustamante, H & Vigneswaran, S 2020, 'Progress, challenges, and opportunities in enhancing NOM flocculation using chemically modified chitosan: A review towards future development', Environmental Science: Water Research and Technology, vol. 6, no. 1, pp. 45-61.
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© 2019 The Royal Society of Chemistry. Natural organic matter (NOM) occurs ubiquitously in water bodies and this can greatly affect feed or raw water quality (taste, colour, odour, bacterial growth). Furthermore, it reduces the performance of the coagulation-based water treatment process. Because the NOM content and its chemical complexity are increasing throughout the world, the removal of NOM from water has become a major challenge in supplying the required amounts of good quality water. The coagulation-flocculation process is widely used for purifying urban water supplies. However, it is not always sufficiently successful in removing the augmented NOM in the feed water, mostly because the polyelectrolytes currently used as coagulants/flocculants cannot effectively interact with all the NOM components consisting of different functional groups, molecular weights, charges, and hydrophobicity. Within the class of polyelectrolytes, chitosan (Cs), which is produced by the deacetylation of abundantly available chitin, has been tested in removing NOM. The effectiveness of Cs can be further improved by chemically modifying the abundant free amino and hydroxyl groups along the Cs chain backbone. This will provide new functional groups that can increase the positive charges, molecular weight, and allow for solubility over a wider pH range, as well as introduce tailored groups which interact in an optimised way with NOM, thereby reducing the solubility of the formed complexes. This paper critically reviews the chemistry of the formed polyelectrolyte/NOM complexes and provides information on how this can be taken advantage of, to identify modified chemical structures of Cs to improve NOM removal in water treatment strategies.
Meena, NK, Nimbalkar, S, Fatahi, B & Yang, G 2020, 'Effects of soil arching on behavior of pile-supported railway embankment: 2D FEM approach', Computers and Geotechnics, vol. 123.
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© 2020 Elsevier Ltd The construction of railway embankment on soft soil is a challenging task for practitioners. In the past, several approaches have been employed in practice to overcome this problem. Pile foundation is considered one of the reliable solutions for soft ground. In a pile-supported railway embankment, soil arching plays a vital role in the efficient load transfer to the piles. In this study, the soil arching phenomenon in a granular embankment subjected to train induced loading is demonstrated based on the two-dimensional (2D) finite element modeling approach. A 2D plane strain idealization is used to convert a real three-dimensional (3D) case into 2D. The effects of the piled railway embankment properties on soil arching are investigated. It is found that pile modulus, embankment modulus and friction angle affect the arching mechanism significantly. Pile spacing (s) variation affects soil arching (i.e., the arching zone can be increased by reducing s). In addition, the height and shape of arching are studied. A comparison with the available analytical design methods for embankments is presented which indicates inconsistencies in the previously published results.
Miller, AD, Coleman, MA, Clark, J, Cook, R, Naga, Z, Doblin, MA, Hoffmann, AA, Sherman, CDH & Bellgrove, A 2020, 'Local thermal adaptation and limited gene flow constrain future climate responses of a marine ecosystem engineer', EVOLUTIONARY APPLICATIONS.
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Mojiri, A, Zhou, JL, Robinson, B, Ohashi, A, Ozaki, N, Kindaichi, T, Farraji, H & Vakili, M 2020, 'Pesticides in aquatic environments and their removal by adsorption methods', Chemosphere, vol. 253.
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© 2020 Elsevier Ltd Although pesticides are widely used in agriculture, industry and households, they pose a risk to human health and ecosystems. Based on target organisms, the main types of pesticides are herbicides, insecticides and fungicides, of which herbicides accounted for 46% of the total pesticide usage worldwide. The movement of pesticides into water bodies occurs through run-off, spray drift, leaching, and sub-surface drainage, all of which have negative impacts on aquatic environments and humans. We sought to define the critical factors affecting the fluxes of contaminants into receiving waters. We also aimed to specify the feasibility of using sorbents to remove pesticides from waterways. In Karun River in Iran (1.21 × 105 ng/L), pesticide concentrations are above regulatory limits. The concentration of pesticides in fish can reach 26.1 × 103 μg/kg, specifically methoxychlor herbicide in Perca fluviatilis in Lithuania. During the last years, research has focused on elimination of organic pollutants, such as pesticides, from aqueous solution. Pesticide adsorption onto low-cost materials can effectively remediate contaminated waters. In particular, nanoparticle adsorbents and carbon-based adsorbents exhibit high performance (nearly 100%) in removing pesticides from water bodies.
Moon, DH, Chung, WJ, Chang, SW, Lee, SM, Kim, SS, Jeung, JH, Ro, YH, Ahn, JY, Guo, W, Ngo, HH & Dinh, DN 2020, 'Fabrication and characterization of Ni-Ce-Zr ternary disk-shaped catalyst and its application for low-temperature CO2 methanation', FUEL, vol. 260.
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Muniyasamy, A, Sivaporul, G, Gopinath, A, Lakshmanan, R, Altaee, A, Achary, A & Velayudhaperumal Chellam, P 2020, 'Process development for the degradation of textile azo dyes (mono-, di-, poly-) by advanced oxidation process - Ozonation: Experimental & partial derivative modelling approach', Journal of Environmental Management, vol. 265, pp. 110397-110397.
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Naidu, G, Tijing, L, Johir, MAH, Shon, H & Vigneswaran, S 2020, 'Hybrid membrane distillation: Resource, nutrient and energy recovery', JOURNAL OF MEMBRANE SCIENCE, vol. 599.
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Nguyen, HT, Yoon, Y, Ngo, HH & Jang, A 2020, 'The application of microalgae in removing organic micropollutants in wastewater', Critical Reviews in Environmental Science and Technology.
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© 2020, © 2020 Taylor & Francis Group, LLC. Micropollutants have become a serious environmental problem with several negative outcomes for human health and ecosystems. Many efforts have been made to remove micropollutants using a variety of physical, chemical and biological methods. By far, the most attention has been paid to microalgae-based technologies for wastewater treatment in order to obtain high-quality effluents, recover algal biomass for fertilizers, protein-rich feed, biofuel, and put them to other practical use. This paper reviews the potential of microalgae-based systems for the removal of organic micropollutants from open ponds to closed photobioreactors coupled by suspended microalgal cells, immobilized cells, or microalgae-microbial consortia. The inhibition of micropollutants on microalgae growth as well as micropollutant removal mechanisms performed by microalgae-based systems are also discussed. Other treatment methods for the removal of micropollutants are analyzed to show the advantages and limitations of microalgae-based treatment strategies, from which some possible combined systems can be suggested. Finally, some recommendations for future studies on this topic are proposed. (Figure presented.).
Nguyen, LN, Commault, AS, Kahlke, T, Ralph, PJ, Semblante, GU, Johir, MAH & Nghiem, LD 2020, 'Genome sequencing as a new window into the microbial community of membrane bioreactors - A critical review.', Science of the Total Environment, vol. 704, pp. 135279-135279.
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Recent developed sequencing techniques have resulted in a new and unprecedented way to study biological wastewater treatment, in which most organisms are uncultivable. This review provides (i) an insight on state-of-the-art sequencing techniques and their limitations; (ii) a critical assessment of the microbial community in biological reactor and biofouling layer in a membrane bioreactor (MBR). The data from high-throughput sequencing has been used to infer microbial growth conditions and metabolisms of microorganisms present in MBRs at the time of sampling. These data shed new insight to two fundamental questions about a microbial community in the MBR process namely the microbial composition (who are they?) and the functions of each specific microbial assemblage (what are their function?). The results to date also highlight the complexity of the microbial community growing on MBRs. Environmental conditions are dynamic and diverse, and can influence the diversity and structural dynamics of any given microbial community for wastewater treatment. The benefits of understanding the structure of microbial communities on three major aspects of the MBR process (i.e. nutrient removal, biofouling control, and micropollutant removal) were symmetrically delineated. This review also indicates that the deployment of microbial community analysis for a practical engineering context, in terms of process design and system optimization, can be further realized.
Nguyen, LN, Truong, MV, Nguyen, AQ, Johir, MAH, Commault, AS, Ralph, PJ, Semblante, GU & Nghiem, LD 2020, 'A sequential membrane bioreactor followed by a membrane microalgal reactor for nutrient removal and algal biomass production', Environmental Science: Water Research and Technology, vol. 6, no. 1, pp. 189-196.
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© 2019 The Royal Society of Chemistry. A hybrid process combining a single compartment aerobic membrane bioreactor (MBR) and a membrane microalgal reactor (MMR) was evaluated for nutrient removal and microalgal biomass production. When operated without biomass extraction, the microalgal biomass in the MMR reached 920 mg L-1 on day 18 and then collapsed, rendering nutrient removal ineffective. Stable operation of the MMR was achieved by regular biomass extraction (i.e. 1/30 of the microalgal biomass in the reactor daily). The biomass production at steady state was approximately 26 g m-3 d-1. The NO3- and PO43- uptake values by microalgae were 4.0 ± 1.1 and 1.5 ± 0.9 g m-3 d-1, respectively. A facile flocculation and separation technique capable of recovering 98% microalgal biomass was demonstrated. Although the hybrid process can significantly enhance nutrient removal and biomass production, further research is needed to intensify the microalgal growth rate. At the current microalgal growth rate, a large MMR volume (37 times that of the MBR) is necessary for synchronous operation.
Nguyen, NC, Duong, HC, Nguyen, HT, Chen, SS, Le, HQ, Ngo, HH, Guo, W, Duong, CC, Le, NC & Bui, XT 2020, 'Forward osmosis–membrane distillation hybrid system for desalination using mixed trivalent draw solution', Journal of Membrane Science, vol. 603.
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© 2020 Elsevier B.V. Finding suitable draw solutions is still a major problem when developing FO technologies. This study represents the first time a mixed trivalent draw solution containing of EDTA–2Na and Na3PO4 was systemically studied for FO performance. The objective here was to achieve simultaneously low reverse salt flux and high water flux. The FO results showed that the mixed trivalent draw solution-based 0.3 M EDTA–2Na and 0.55 M Na3PO4 underwent higher water flux (Jw = 9.17 L/m2⋅h) than that of pure 0.85 M EDTA-2Na (Jw = 7.02 L/m2⋅h) due to its lower viscosity. Additionally, the specific reverse salt flux caused by mixing 0.3 M EDTA–2Na with 0.55 M Na3PO4 draw solution was only 0.053 g/L using DI water as the feed solution. Donnan equilibrium force and formed complexation of [EDTANa]3-, [HPO4Na]- with the FO membrane are believed to constitute the main mechanism for minimizing salt leakage from the mixed draw solution. Moreover, the FO desalination process utilizing the mixed trivalent draw solution achieved water fluxes of 6.12 L/m2⋅h with brackish water (TDS = 5000 mg/L) and 3.10 L/m2⋅h with seawater (TDS = 35,000 mg/L) as the feed solution. Lastly, diluted mixed trivalent draw solution following the FO process was effectively separated using the MD process with salt rejection >99.99% at a mild feed temperature of 55 °C.
Nguyen, TH, Tran, HN, Vu, HA, Trinh, MV, Nguyen, TV, Loganathan, P, Vigneswaran, S, Nguyen, TM, Trinh, VT, Vu, DL & Nguyen, THH 2020, 'Laterite as a low-cost adsorbent in a sustainable decentralized filtration system to remove arsenic from groundwater in Vietnam.', The Science of the total environment, vol. 699, pp. 134267-134267.
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In the Red River Delta, Vietnam, arsenic (As) contamination of groundwater is a serious problem where more than seventeen million people are affected. Millions of people in this area are unable to access clean water from the existing centralized water treatment systems. They also cannot afford to buy expensive household water filters. Similar dangerous situations exist in many other countries and for this reason there is an urgent need to develop a cost-effective decentralized filtration system using new low-cost adsorbents for removing arsenic. In this study, seven locally available low-cost materials were tested for arsenic removal by conducting batch adsorption experiments. Of these materials, a natural laterite (48.7% Fe2O3 and 18.2% Al2O3) from Thach That (NLTT) was deemed the most suitable adsorbent based on arsenic removal performance, local availability, stability/low risk and cost (US$ 0.10/kg). Results demonstrated that the adsorption process was less dependent on the solution pH from 2.0 to 10. The coexisting anions competed with As(III) and As(V) in the order, phosphate > silicate > bicarbonate > sulphate > chloride. The adsorption process reached a fast equilibrium at approximately 120-360 min, depending on the initial arsenic concentrations. The Langmuir maximum adsorption capacities of NLTT at 30 °C were 512 μg/g for As(III) and 580 μg/g for As(V), respectively. Thermodynamic study conducted at 10 °C, 30 °C, and 50 °C suggested that the adsorption process of As(III) and As(V) was spontaneous and endothermic in nature. A water filtration system packed with NLTT was tested in a childcare centre in the most disadvantaged community in Ha Nam province, Vietnam, to determine arsenic removal performance in an operation lasting six months. Findings showed that the system reduced total arsenic concentration in groundwater from 122 to 237 μg/L to below the Vietnam drinking water standard of 10 μg/L.
Nguyen, TKL, Ngo, HH, Guo, WS, Chang, SW, Nguyen, DD, Nghiem, LD & Nguyen, TV 2020, 'A critical review on life cycle assessment and plant-wide models towards emission control strategies for greenhouse gas from wastewater treatment plants', Journal of Environmental Management, vol. 264.
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© 2020 Elsevier Ltd For decades, there has been a strong interest in mitigating greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs). Numerous models were developed to measure the emissions and propose the quantification. Existing studies looked at the relationship between GHG emissions and operational cost (OCI), which is one of the most important indicators for decision-makers. Other parameters that can influence the control strategies include the effluent quality (EQI) and total environmental impacts. Plant-wide models are reliable methods to examine the OCI, EQI and GHG emissions while Life cycle assessment (LCA) works to assess the potential environmental impacts. A combined LCA and plant-wide model proved to be a valuable tool evaluating and comparing strategies for the best performance of WWTPs. For this study involving a WWTP, the benchmark model is used while LCA is the decision tool to find the most suitable treatment strategy. LCA adds extra criteria that complement the existing criteria provided by such models. Complementing the cost/performance criteria is proposed for plant-wide models, including environmental evaluation, based on LCA, which provides an overall better assessment of WWTPs. It can capture both the dynamic effects and potential environmental impacts. This study provides an overview of the integration between plant-wide models and LCA.
Nguyen, TTQ, Loganathan, P, Nguyen, TV & Vigneswaran, S 2020, 'Removing arsenic from water with an original and modified natural manganese oxide ore: batch kinetic and equilibrium adsorption studies.', Environmental science and pollution research international, vol. 27, no. 5, pp. 5490-5502.
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Arsenic contamination of drinking water is a serious water quality problem in many parts of the world. In this study, a low-cost manganese oxide ore from Vietnam (Vietnamese manganese oxide (VMO)) was firstly evaluated for its performance in arsenate (As(V)) removal from water. This material contains both Mn (25.6%) and Fe (16.1%) mainly in the form of cryptomelane and goethite minerals. At the initial As(V) concentration of 0.5 mg/L, the adsorption capacity of original VMO determined using the Langmuir model was 0.11 mg/g. The modified VMOs produced by coating VMO with iron oxide (Fea-VMO) and zirconium oxide (Zra-VMO) at 110 °C and 550 °C achieved the highest As(V) adsorption capacity when compared to three other methods of VMO modifications. Langmuir maximum adsorption capacities of Fea-VMO and Zra-VMO at pH 7.0 were 2.19 mg/g and 1.94 mg/g, respectively, nearly twenty times higher than that of the original VMO. Batch equilibrium adsorption data fitted well to the Langmuir, Freundlich, and Temkin models and batch kinetics adsorption data to pseudo-first order, pseudo-second order, and Elovich models. The increase of pH progressively from 3 to 10 reduced As(V) adsorption with a maximum reduction of 50-60% at pH 10 for both original and modified VMOs. The co-existing oxyanions considerably weakened the As(V) removal efficiency because they competed with As(V) anions. The competition order was PO43- > SiO32- > CO32- > SO42-. The characteristics of the original and modified VMOs evaluated using SEM, FTIR, XRD, XRF, surface area, and zeta potential explained the As(V) adsorption behaviour.
Nguyen, XC, Tran, TCP, Hoan, H, Nguyen, TP, Chang, SW, Dinh, DN, Guo, W, Kumar, A, Duong, DL & Quang-Vu, B 2020, 'Combined biochar vertical flow and free-water surface constructed wetland system for dormitory sewage treatment and reuse', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 713.
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Ni, B-J, Zeng, S, Wei, W, Dai, X & Sun, J 2020, 'Impact of roxithromycin on waste activated sludge anaerobic digestion: Methane production, carbon transformation and antibiotic resistance genes', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 703.
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Nuruzzaman, M, Ren, J, Liu, Y, Rahman, MM, Shon, HK & Naidu, R 2020, 'Hollow Porous Silica Nanosphere with Single Large Pore Opening for Pesticide Loading and Delivery', ACS APPLIED NANO MATERIALS, vol. 3, no. 1, pp. 105-113.
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Organ, B, Huang, Y, Zhou, JL, Yam, Y-S, Mok, W-C & Chan, EFC 2020, 'Simulation of engine faults and their impact on emissions and vehicle performance for a liquefied petroleum gas taxi', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 716.
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Pathak, N, Phuntsho, S, Van, HT, Johir, MAH, Ghaffour, N, Leiknes, T, Fujioka, T & Shon, HK 2020, 'Simultaneous nitrification-denitrification using baffled osmotic membrane bioreactor-microfiltration hybrid system at different oxic-anoxic conditions for wastewater treatment', JOURNAL OF ENVIRONMENTAL MANAGEMENT, vol. 253.
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Paull, NJ, Krix, D, Irga, PJ & Torpy, FR 2020, 'Airborne particulate matter accumulation on common green wall plants.', International journal of phytoremediation, pp. 1-13.
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In order to better design greening systems for effective particulate matter (PM) removal, it is important to understand the impact leaf traits have on PM deposition. There are however, inconsistences amongst the leaf traits that have previously been correlated with PM accumulation. The aim of this paper was to identify vegetation characteristics of green wall plants that were associated with the accumulation of particulate matter. To determine patterns associated with different leaf morphologies, eleven common ornamental plant species were sampled across 15 sites, over a 6 month duration. PM deposition was determined gravimetrically and its associated size fractions determined microscopically. Linear mixed models were used to identify statistical patterns relating to differences in PM deposition across plant species. PM deposition and the relative frequencies of particle size fractions were found to be statistically different among species, sites and months. Green wall plants were shown to be effective at PM accumulation as all of the assessed plant species had equivalent PM removal efficiency, with minimal evidence of influential leaf characteristics that could enhance PM removal.
Peng, L, Nie, W-B, Ding, J, Ni, B-J, Liu, Y, Han, H-J & Xie, G-J 2020, 'Denitrifying Anaerobic Methane Oxidation and Anammox Process in a Membrane Aerated Membrane Bioreactor: Kinetic Evaluation and Optimization.', Environmental science & technology.
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Denitrifying anaerobic methane oxidation (DAMO) coupled to anaerobic ammonium oxidation (anammox) is a promising technology for complete nitrogen removal with economic and environmental benefit. In this work, a model framework integrating DAMO and anammox process was constructed based on suspended-growth systems. The proposed model was calibrated and validated using experimental data from a sequencing batch reactor and a membrane aerated membrane bioreactor (MAMBR). The model managed to describe removal rates of ammonium (NH4+), nitrite (NO2-), and total nitrogen, as well as biomass changes of DAMO archaea, DAMO bacteria, and anaerobic ammonium oxidizing bacteria (AnAOB) in both reactors. The estimated parameter values revealed that DAMO archaea possessed properties of faster growth and higher biomass yield in suspended-growth systems compared to those in attached-growth systems (e.g., biofilm). Model simulation demonstrated that solid retention time (SRT) was effective in washing out DAMO bacteria, but retaining DAMO archaea and AnAOB in the MAMBR. The optimal SRT and nitritation efficiency (the ratio of the NO2- to the sum of NH4+ and NO2- in the MAMBR influent) were simulated so that 99% of total nitrogen was removed to meet the discharge standard. MAMBR further suggested to be operated with SRT between 15 and 30 days so that the optimal nitritation efficiency could be minimized to 49% for cost savings.
Pham, TT, Ngo, HH, Tran, VS & Nguyen, MK 2020, 'Removal of As (V) from the aqueous solution by a modified granular ferric hydroxide adsorbent.', The Science of the total environment, vol. 706.
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A novel adsorbent was prepared in granular form from iron (III) hydroxide and other additives to remove arsenate (As (V)) from aqueous solution. Adsorption of As (V) onto the adsorbent in batch experiments was analyzed to understand the adsorption mechanism, affecting factors, and adsorption isotherms. The optimal working conditions for the developed adsorbent were at pH 3, 30 °C and 50 g/L. The adsorption of arsenate onto the adsorbent occurred rapidly in the first 10 min and reached equilibrium in 2 h. The Langmuir isotherm was found to be best fitted the adsorption. The pre- and post-adsorption adsorbents were characterized by SEM, BET, FTIR, XRD, and Zeta potential techniques. Experimental results clearly demonstrated the potential impact of elemental composition, crystallinity, surface morphology, and other physico-chemical properties of the adsorbent on the adsorption performance variety. The experimental results with the pilot scale treatment system revealed that the adsorbent can be applied successfully and lead to a very efficient drinking water treatment system, at a competitive cost compared to the water market in Hanoi, Vietnam.
Phuntsho, S, Kim, JE, Tran, VH, Tahara, S, Uehara, N, Maruko, N, Matsuno, H, Lim, S & Shon, HK 2020, 'Free-standing, thin-film, symmetric membranes: Next-generation membranes for engineered osmosis', Journal of Membrane Science, vol. 607, pp. 118145-118145.
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Pramanik, BK, Long, DN & Hai, FI 2020, 'Extraction of strategically important elements from brines: Constraints and opportunities', WATER RESEARCH, vol. 168.
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Punetha, P, Nimbalkar, S & Khabbaz, H 2020, 'Analytical Evaluation of Ballasted Track Substructure Response under Repeated Train Loads', International Journal of Geomechanics, vol. 20, no. 7.
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© 2020 American Society of Civil Engineers. The irrecoverable deformations in the substructure layers are detrimental to the track stability and demand frequent maintenance. With an escalation in axle load and traffic volume, the frequency of maintenance operations has remarkably increased. Consequently, there is an inevitable need to predict the long-term behavior of the track substructure layers. This article presents a methodology to evaluate the recoverable and irrecoverable responses of the substructure layers under the train-induced repetitive loads. The present method utilizes an integrated approach combining track loading, resiliency, and settlement models. The track substructure layers are simulated as lumped masses that are connected by springs and dashpots. The method is successfully validated against the field investigation data reported in the literature. A parametric study is conducted to investigate the influence of substructure layer properties on the track response. The results reveal that the response of each track layer is significantly influenced by the neighboring layer properties and the incorporation of multilayered track structure enables more accurate prediction of track behavior. The present analytical approach is simple, computationally efficient and may assist the practicing engineers in the safer design of the ballasted track.
Punetha, P, Nimbalkar, S & Khabbaz, H 2020, 'Evaluation of additional confinement for three-dimensional geoinclusions under general stress state', CANADIAN GEOTECHNICAL JOURNAL, vol. 57, no. 3, pp. 453-461.
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Rasouli, H & Fatahi, B 2020, 'Geofoam blocks to protect buried pipelines subjected to strike-slip fault rupture', Geotextiles and Geomembranes.
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© 2019 Elsevier Ltd This paper proposes using geofoam blocks to improve the safety of buried steel pipelines under permanent ground deformation due to strike-slip fault rupture. Since these geofoam blocks are deformable, they can compress during fault rupture and thus reduce the pressure imposed on the pipeline by the surrounding soil. This means that the pipe can sustain a higher level of tectonic deformations. For the pipeline system adopted in this study, the geofoam blocks consist of two 1 m thick blocks at each side and another on the top of the pipeline. The effectiveness of this configuration is then assessed in comparison to the conventional buried pipeline by three dimensional numerical simulations that consider the interaction between soil and structure and the impact of critical parameters such as the pipeline-fault trace crossing angle, geofoam blocks thickness and the internal pressure of the pipeline. The results indicated that the geofoam blocks reduced the axial tensile strain of non-pressurised pipeline from the unacceptable 4.16% to the safe level of 0.75% when the crossing angle was 135°. In addition, geofoam blocks successfully decreased the maximum ovalisation parameter and compressive strain of the non-pressurised pipeline from 0.237 and −25.8% to 0.065 and −0.47%, respectively when the crossing angle was 65°.
Rasouli, H, Fatahi, B & Nimbalkar, S 2020, 'Liquefaction and Post-liquefaction Assessment of Lightly Cemented Sands', Canadian Geotechnical Journal.
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Ren, LF, Ngo, HH, Bu, C, Ge, C, Ni, SQ, Shao, J & He, Y 2020, 'Novel external extractive membrane bioreactor (EMBR) using electrospun polydimethylsiloxane/polymethyl methacrylate membrane for phenol-laden saline wastewater', Chemical Engineering Journal, vol. 383.
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© 2019 Elsevier B.V. Phenol-laden saline wastewaters can adversely affect water, groundwater, soil, organisms and ecosystems. Given that frequently-used biodegradation process is generally inhibited by salinity, this work aims to solve the problem through a novel configuration of external extractive membrane bioreactor (EMBR) for the objective of simultaneous phenol permeation, salt rejection and biodegradation. Contact angles of 160.9 ± 2.2° (water) and 0.0° (phenol) were observed on the electrospun polydimethylsiloxane/polymethyl methacrylate (PDMS/PMMA) membrane, suggesting this superhydrophobic/superorganophilic membrane was suitable for separating phenol from water-soluble salt. Phenol ranging from 14.1 ± 2.7 to 290.7 ± 10.4 mg/L (stages 1 to 8) was continuously permeated and completely biodegraded in external EMBR under a hydraulic retention time (HRT) of 24 h, which corresponded with detoxification performance improving from 6.3% to 70.5%. After phenol exposure of 8 stages, Proteobacteria and Saccharibacteria became the main phyla for microorganisms. Enumeration of functional genes (phe, amoA, narG, nirS) confirmed that phenol was mainly consumed by denitrifiers and other heterotrophs as the sole carbon and energy source via oxidation and ring cleavage. As bacterial responses, these genes’ proliferation was promoted under low phenol concentrations but inhibited under high phenol concentrations. Meanwhile, results of extracellular polymeric substances revealed that protein was the key substance in toxicity resistance, phenol adsorption and transfer.
Ren, Y, Huu, HN, Guo, W, Wang, D, Peng, L, Ni, B-J, Wei, W & Liu, Y 2020, 'New perspectives on microbial communities and biological nitrogen removal processes in wastewater treatment systems', BIORESOURCE TECHNOLOGY, vol. 297.
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Roobavannan, M, Kandasamy, J, Pande, S, Vigneswaran, S & Sivapalan, M 2020, 'Sustainability of agricultural basin development under uncertain future climate and economic conditions: A socio-hydrological analysis', Ecological Economics, vol. 174.
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© 2020 Elsevier B.V. A socio-hydrological model is used to forecast future conditions in a river basin arising from changes in climate and the economy in order to learn about macroeconomic conditions that would yield pathways for sustainable development and how they may be affected by changes in climate and the economy. The study uses a system dynamics model with endogenous social values and preferences and exogenous climate and economic drivers. Basin scale sustainability is defined as a function of economic growth, provision of environmental services and equality within the basin. The analysis reveals that a diversified basin economy is important to achieve sustainable development. Under current climate conditions, a higher level of diversification in the basin's economy increases sustainability. Higher current capital growth rates, e.g., >2% of the current rate, would also lead to more sustainable development of a kind that is less affected by the availability of water and robust to vagaries of climate change. The results suggest that policy-makers and resource managers should focus on measures to diversify the economy when it is thriving, but also consider the capacity of society to adapt to unpredictable shocks to the system.
Samadi-Boroujeni, H, Abbasi, S, Altaee, A & Fattahi-Nafchi, R 2020, 'Numerical and Physical Modeling of the Effect of Roughness Height on Cavitation Index in Chute Spillways', International Journal of Civil Engineering, vol. 18, pp. 539-550.
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© 2019, Iran University of Science and Technology. This study presents the results of physical and numerical modeling of the effect of bed roughness height of chute spillways on the cavitation index. A 1:50-scale physical hydraulic model of the chute spillway of Surk Dam was constructed at the hydraulic laboratory of Shahrekord University, Iran. The experiments were conducted for different flow rates and the parameters of pressure, velocity, and flow depth in 26 positions along the chute. Finally, the ANSYS-FLUENT model was calibrated in the chute spillway using the experimental data by assumptions of two-phase volume of fluid and k–ε (RNG) turbulence models. The cavitation index in different sections of the chute spillway was calculated for different values of bed roughness including the roughness heights of 1, 2, and 2.5 mm. Results showed that the minimum values of the cavitation index were 0.2906, 0.2733, and 0.2471 for the roughness heights of 1, 2, and 2.5 mm, respectively. The statistical significance analysis showed that reducing the roughness height from 2.5 to 1 mm would not change significantly the value of the cavitation index at 95% confidence interval.
Samaei, SM, Gato-Trinidad, S & Altaee, A 2020, 'Performance evaluation of reverse osmosis process in the post-treatment of mining wastewaters: Case study of Costerfield mining operations, Victoria, Australia', Journal of Water Process Engineering, vol. 34.
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© 2019 Elsevier Ltd Reverse Osmosis (RO) membrane has been used for treatment and purification of industrial wastewaters including those from the mining industry before being discharged to receiving body or reuse for applications that are fit for purpose. This study evaluates the performance of Reverse Osmosis (RO) plant as a post-treatment process in mining operations in Victoria, Australia. The data analysis shows that the RO unit significantly improves the quality of the final permeate before discharged to surface waters. Considering average rejection efficiency for the entire evaluated period, turbidity, total dissolved solids (TDS), Antimony, Arsenic, Nickel, Zinc and Iron concentrations are reduced by 85 %, 96 %, 95 %, 66 %, 82 %, 48 % and 10 %, respectively in the RO permeate compared to the feed water. Although the quality of the RO permeate was in a desirable condition in most days of the evaluated years, TDS concentrations on the October 11 and 20,2016 and November 14, 2017 were higher than the limits specified by Environmental Protection Authority (EPA) Victoria. Anomalies regarding antimony levels in RO permeate occurred in September and November 2016 as well as August 2017 due to inconsistency in the RO feed quality. This resulted in fouling of RO membranes and contributed to discharge non-compliance with EPA licence conditions on TDS and antimony. Discharge to waterways was suspended over the period when TDS and antimony contents were above the EPA guidelines. Changes in the pre-treatment reduced the turbidity of the feed water and improved the performance of the RO system to comply with the discharge guidelines.
Satya, A, Harimawan, A, Haryani, GS, Johir, MAH, Vigneswaran, S, Ngo, HH & Setiadi, T 2020, 'Batch study of cadmium biosorption by carbon dioxide enriched aphanothece sp. dried biomass', Water (Switzerland), vol. 12, no. 1.
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© 2020 by the authors. The conventional method for cadmium removal in aqueous solutions (1-100 mg/L) is ineffective and inefficient. Therefore, a batch biosorption reactor using a local freshwater microalga (originating from an urban lake, namely, Situ Rawa Kalong-Depok) as dried biosorbent was tested. Biosorbent made from three kinds of cyanobacterium Aphanothece sp. cultivars (A0, A8, and A15) were used to eliminate cadmium (Cd2+) ions in aqueous solution (1-7 mg/L). The biosorbents were harvested from a photobioreactor system enriched with carbon dioxide gas of 0.04% (atmospheric), 8%, and 15% under continuous light illumination of about 5700-6000 lux for 14 d of cultivation. Produced dried biosorbents had Brunauer-Emmet-Teller (BET) surface area ranges of 0.571-1.846 m2/g. Biosorption of Cd2+ was pH and concentration dependent. Sorption was spontaneous (G =-8.39 to-10.88 kJ/mol), exothermic (H=-41.85 to-49.16 kJ/mol), and decreased randomness (S =-0.102 to-0.126 kJ/molK) on the interface between solid and liquid phases when the process was completed. The kinetic sorption data fitted best to the pseudo-second-order model (k2 = 2.79 x 10-2, 3.96 x 10-2, and 4.54 x 10-2 g/mgmin). The dried biosorbents of A0, A8, and A15, after modeling with the Langmuir and Dubinin-Radushkevich isotherm models, indicated that cadmium binding occurred through chemisorption (qmax, D-R = 9.74 x 10-4, 4.79 x 10-3, and 9.12 x 10-3 mol/g and mean free energy of 8.45, 11.18, and 11.18 kJ/mol) on the monolayer and homogenous surface (qmax, Langmuir of 12.24, 36.90, and 60.24 mg/g). In addition, the results of SEM, EDX, and FTIR showed that there were at least nine functional groups that interacted with Cd2+ (led to bond formation) after biosorption through cation exchange mechanisms, and morphologically the surfaces changed after biosorption. Biosorbent A15 indicated the best resilient features over three cycles of sorption-desorption using 1 M HCl as the desorbing eluent. These biosorb...
Shanmugam, S, Ngo, HH & Wu, YR 2020, 'Advanced CRISPR/Cas-based genome editing tools for microbial biofuels production: A review', Renewable Energy.
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© 2019 Elsevier Ltd With rapid progress in the fields of synthetic biology and metabolic engineering, there are possible applications to generate a wide range of advanced biofuels with maximized yield and productivity to achieve a more sustainable bioprocess with reduced carbon footprints. Among the diverse molecular biology tools, clustered regularly interspaced short palindromic repeats-CRISPR-associated proteins (CRISPR-Cas) technology stands out with potential targeted genome editing, exhibiting a more precise and accurate gene knock-out and knock-in system better than its predecessors, for example zinc finger nucleases (ZFN) and transcription activator-like effector nucleases (TALEN). There are reports involved in the advanced microbial genome engineering tools for the biofuels production; however, there is lack of a comprehensive review about the CRISPR-Cas based-techniques in improved biofuel production along with the strategies to reduce the off-target effect that ensures the success and safety of this method. Therefore, in this review we attempt to systematically comment on the mechanism of CRISPR-Cas and its application to microbial biofuels production. This includes bioethanol, biobutanol as well as other hydrocarbons that sequentially follow various suggestions on enhancing the efficiency of targeting genes. The role of inducible on/off genetic circuits in response to environmental stimuli in the regulation of targeted genome editing (TGE) by minimizing metabolic burden and maximizing fermentation efficiency is also discussed. The relevant stringent regulatory demands to ensure minimal off-target cleavage with maximum efficiency coupled with complete biosafety of this technology are considered. It can be concluded that the recent development of CRISPR-Cas technology should open a new avenue in creating microbial biorefineries for potentially enhanced biofuel production.
Sornalingam, K, McDonagh, A, Canning, J, Cook, K, Johir, MAH, Zhou, JL & Ahmed, MB 2020, 'Photocatalysis of 17 alpha-ethynylestradiol and estriol in water using engineered immersible optical fibres and light emitting diodes', JOURNAL OF WATER PROCESS ENGINEERING, vol. 33.
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Surawski, NC, Macdonald, LM, Baldock, JA, Sullivan, AL, Roxburgh, SH & Polglase, PJ 2020, 'Exploring how fire spread mode shapes the composition of pyrogenic carbon from burning forest litter fuels in a combustion wind tunnel', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 698.
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Sutherland, DL, Howard-Williams, C, Ralph, P & Hawes, I 2020, 'Environmental drivers that influence microalgal species in meltwater pools on the McMurdo Ice Shelf, Antarctica', POLAR BIOLOGY.
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Sutherland, DL, Park, J, Heubeck, S, Ralph, PJ & Craggs, RJ 2020, 'Size matters - Microalgae production and nutrient removal in wastewater treatment high rate algal ponds of three different sizes', ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS, vol. 45.
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Sutherland, DL, Park, J, Ralph, PJ & Craggs, RJ 2020, 'Improved microalgal productivity and nutrient removal through operating wastewater high rate algal ponds in series', Algal Research, vol. 47.
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© 2020 Elsevier B.V. High rate algal ponds are recognised as a cost effective and efficient upgrade to conventional wastewater ponds for the treatment of a wide range of wastewaters. Their design allows microalgae to proliferate, which, in turn, results in high levels of nutrient removal, via algal assimilation. Furthermore, these ponds offer the opportunity to recover resources, in the form of algal biomass, for beneficial re-use, thus creating a circular bio-economy using wastewater. However, both increased microalgal biomass and nutrient removal is required to make coupled full-scale systems commercially viable. The performance of high rate algal ponds operated in series, on short hydraulic retention time of 4 days, versus in parallel, on a longer retention time of 8 days, was assessed with respect to nutrient removal and microalgal production. For microalgal productivity, the combined total volatile suspended solids (organic matter) and chlorophyll-a biomass were significantly higher (p < 0.01) under Series (191 ± 41 kg per day for volatile suspended solids) than Parallel (127 ± 18 kg per day) operation. The combined total dissolved inorganic nitrogen removed per day was significantly higher (p < 0.01) under Series (23 ± 4 kg of nitrogen per day) than Parallel (17 ± 4 kg) operation. The total amount of phosphorus removed per day was unaffected by mode of operation. Higher biomass production under short retention times came at the expense of nitrogen removal but treatment of the harvested effluent through a second pond in series, resulted in overall higher daily nitrogen removal and biomass production than ponds in parallel, for the same volume of wastewater treated. This study has demonstrated that with simple modifications to pond operation higher microalgal yields and improved effluent water quality without increased capital or operational costs.
Suwaileh, W, Pathak, N, Shon, H & Hilal, N 2020, 'Forward osmosis membranes and processes: A comprehensive review of research trends and future outlook', Desalination, vol. 485, pp. 114455-114455.
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Tahmoorian, F & Khabbaz, H 2020, 'Performance comparison of a MSW settlement prediction model in Tehran landfill', Journal of Environmental Management, vol. 254.
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© 2019 The municipal solid waste (MSW) landfills experience a large post-closure settlement over time. Waste settlement significantly impairs utilities, structures, and the other facilities constructed on top of a landfill. This study presents the settlement mechanisms and the methods of estimating MSW landfill settlements. Since the waste materials exhibit engineering properties which vary depending on many factors such as the location, time, climate, this study also presents the data related to the landfill characteristics, waste composition, waste moisture content, and other physical and chemical properties of waste. In addition, this paper discusses the findings of a settlement investigation conducted at a municipal solid waste landfill in Tehran. In this research, based on the collected field data and data obtained from the available literature, a technical management tool for MSW closed landfills has been developed using MATLAB, which aims to predict time dependent settlement under self-weight and surcharge loads in landfills considering various related parameters, leachate, gas generation, and moisture distribution, coefficients of compression, whilst it calculates different properties of wastes, and determines the landfill slope stability under various conditions. This user-friendly program captures the variation of the model parameters with time. The results of the verification process indicate that the results from the technical management tool have been in a very good agreement with the measured field settlement data, collected from Tehran landfill. Moreover, the results of sensitivity analysis of the model in regard to variation of input parameters indicate that there are two prominent characteristics, having significant impacts on the overall landfill settlement. These characteristics are the landfill height and the compressibility parameters. The outcomes of this study can improve the confidence for design and construction on MSW landfills. It may r...
Thu, TN, Huu, HN, Guo, W & Wang, XC 2020, 'A new model framework for sponge city implementation: Emerging challenges and future developments', JOURNAL OF ENVIRONMENTAL MANAGEMENT, vol. 253.
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Thuy, C-V, Suraski, N, Ristovski, Z, Yuan, C-S, Stevanovic, S, Rahman, SMA, Hossain, FM, Guo, Y, Rainey, T & Brown, RJ 2020, 'The effect of diesel fuel sulphur and vanadium on engine performance and emissions', FUEL, vol. 261.
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Tijing, LD, Dizon, JRC, Ibrahim, I, Nisay, ARN, Shon, HK & Advincula, RC 2020, '3D printing for membrane separation, desalination and water treatment', Applied Materials Today, vol. 18, pp. 1-22.
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© 2019 Elsevier Ltd Additive manufacturing or commonly known as 3D printing is driving innovation in many industries and academic research including the water resource sector. The capability of 3D printing to fabricate complex objects in a fast and cost-effective manner makes it highly desirable over conventional manufacturing processes. Recent years have seen a rapid increase in research using 3D printing for membrane separation, desalination and water purification applications, potentially revolutionizing this field. This review focuses on recent advancements in 3D-printed materials and methods for water-related applications including developments in module spacers, novel filtration and desalination membranes, adsorbents, water remediation, solar steam generation materials, catalysis, etc. The emergence of new 3D printers with higher printing resolution, better efficiency, faster speed, and wider material applicability has garnered more interest and can potentially reshape research and development in this field. The promising potential, challenges and future prospects of 3D printing, additive manufacturing, and materials for water resource and treatment-related applications are all discussed in this review.
To, VHP, Nguyen, TV, Bustamante, H & Vigneswaran, S 2020, 'Effects of extracellular polymeric substance fractions on polyacrylamide demand and dewatering performance of digested sludges', Separation and Purification Technology, vol. 239.
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© 2020 Elsevier B.V. High polymer demand in sludge conditioning is an intractable aspect of the water industry. This study investigated the effects of extracellular polymeric substances (EPS) fractions on polyacrylamide demand for conditioning and dewatering performance. Specifically, it examined aerobically and anaerobically digested sludges from seven full-scale wastewater treatment plants (WWTPs). Our study successfully quantified the contributions of soluble EPS to polyacrylamide demand during conditioning and explained the role of tightly bound EPS (TB-EPS) in determining the digested sludges’ dewatering performance. Results show that the concentrations of soluble EPS in the sludges varied between 92 and 1148 mg/L. Experimental results also demonstrated that between 25% and 80% of polyacrylamides used for conditioning were wasted in “parasitic” reactions with soluble EPS. The residual cationic polyacrylamide left in solution, after the parasitic reactions, was substantial and varied between 35 and 254 mg/L. Despite this outcome, the zeta potential values of dewatered sludge cakes remained negative, i.e. between −24 and −35 mV. These indicated that the residual soluble cationic polyacrylamides would not have been absorbed on the negatively charged sludge particles. This explained the relatively poor performance of the dewatering stage in the treatment plants studied. Furthermore the results suggested the TB-EPS attached to the sludge particles would be responsible for the poor dewatering. We postulated that the TB-EPS would gelify and immobilize the water surrounding the sludge particles. Our study suggested that new and more effective polymers for conditioning are needed to both: (i) reduce polymer demand; and (ii) improve the dewatering performance.
Trevathan-Tackett, SM, Jeffries, TC, Macreadie, PI, Manojlovic, B & Ralph, P 2020, 'Long-term decomposition captures key steps in microbial breakdown of seagrass litter', Science of the Total Environment, vol. 705.
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© 2018 Elsevier B.V. Seagrass biomass represents an important source of organic carbon that can contribute to long-term sediment carbon stocks in coastal ecosystems. There is little empirical data on the long-term microbial decomposition of seagrass detritus, despite this process being one of the key drivers of carbon-cycling in coastal ecosystems, that is, it influences the amount and quality of carbon available for sequestration. Here, our goal was to investigate how litter quality (leaf vs. rhizome/root) and the microbial communities involved in organic matter remineralisation shift over a 2-year field decomposition study north of Sydney, Australia using the temperate seagrass Zostera muelleri. The sites varied in bulk sediment characteristics and the sediment-associated microbial communities, but these variables overall had little influence on long-term seagrass decomposition rates or seagrass-associated microbiomes. The results showed a clear succession of bacterial and archaeal communities for both tissues types from r-strategists such as α- and γ-proteobacteria to K-strategies, including δ-proteobacteria, Bacteroidia and Spirochaetes. We used a new mathematical model to capture how decay rates varied over time and found that two decomposition events occurred for some seagrass leaf samples, possibly due to exudate input from living seagrass roots growing into the litter bag. The new model also indicated that conventional single exponential models overestimate long-term decay rates, and we detected for the first time the refractory, or stable, phase of decomposition for rhizome/root biomass. The stable phase began at approximately 20% mass remaining and after 600 days, and the persistence of rhizome/root biomass was attributed to the anoxic conditions and the preservation of refractory organic matter. While we predict that rhizome/root biomass will contribute more to the long-term sediment carbon stocks, the preservation of leaf carbon may be enhanced at loc...
Van, HT, Lim, S, Park, MJ, Han, DS, Phuntsho, S, Park, H, Matsuyama, H & Shon, HK 2020, 'Fouling and performance of outer selective hollow fiber membrane in osmotic membrane bioreactor: Cross flow and air scouring effects', BIORESOURCE TECHNOLOGY, vol. 295.
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Varjani, S, Joshi, R, Srivastava, VK, Ngo, HH & Guo, W 2020, 'Treatment of wastewater from petroleum industry: current practices and perspectives.', Environmental science and pollution research international.
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Petroleum industry is one of the fastest growing industries, and it significantly contributes to economic growth in developing countries like India. The wastewater from a petroleum industry consist a wide variety of pollutants like petroleum hydrocarbons, mercaptans, oil and grease, phenol, ammonia, sulfide, and other organic compounds. All these compounds are present as very complex form in discharged water of petroleum industry, which are harmful for environment directly or indirectly. Some of the techniques used to treat oily waste/wastewater are membrane technology, photocatalytic degradation, advanced oxidation process, electrochemical catalysis, etc. In this review paper, we aim to discuss past and present scenario of using various treatment technologies for treatment of petroleum industry waste/wastewater. The treatment of petroleum industry wastewater involves physical, chemical, and biological processes. This review also provides scientific literature on knowledge gaps and future research directions to evaluate the effect(s) of various treatment technologies available.
Vo, HNP, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Chen, Z, Wang, XC, Chen, R & Zhang, X 2020, 'Microalgae for saline wastewater treatment: a critical review', Critical Reviews in Environmental Science and Technology, vol. 50, no. 12, pp. 1224-1265.
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© 2019, © 2019 Taylor & Francis Group, LLC. Saline wastewater contains numerous pollutants such as nutrients, heavy metals, micropollutants, and organic pollutants. This kind of wastewater needs to be treated prior to discharging. Compared to other technologies for saline wastewater treatment, the microalgae process is considered to be ‘green’ or environmentally friendly as it generates no secondary pollutants and creates profit. To elucidate the issue, this review investigated the following: (1) the nature of saline wastewater; (2) adaptation of microalgae in saline wastewater; (3) pollutants’ remediation by microalgae in saline wastewater; (4) comparisons with other technologies; and (5) future perspectives. Most importantly, during microalgae process, the saline wastewater is transformed from a waste into a source for biofuel and pigment production. This trend implies to heal the environment, cut remediation expenses and raise revenue.
Vo, HNP, Ngo, HH, Guo, W, Liu, Y, Woong Chang, S, Nguyen, DD, Zhang, X, Liang, H & Xue, S 2020, 'Selective carbon sources and salinities enhance enzymes and extracellular polymeric substances extrusion of Chlorella sp. for potential co-metabolism', Bioresource Technology, vol. 303.
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© 2020 Elsevier Ltd This study investigated the extracellular polymeric substance (EPS) and enzyme extrusion of Chlorella sp. using seven carbon sources and two salinities for potential pollutant co-metabolism. Results indicated that the levels of biomass, EPS and enzymes of microalgae cultured with glucose and saccharose outcompeted other carbon sources. For pigment production, glycine received the highest chlorophyll and carotene, up to 10 mg/L. The EPS reached 30 mg/L, having doubled the amount of protein than carbohydrate. For superoxide dismutase and peroxidase enzymes, the highest concentrations were beyond 60 U/ml and 6 nmol/d.ml, respectively. This amount could be potentially used for degrading 40% ciprofloxacin of concentration 2000 µg/L. When increasing salinity from 0.1% to 3.5%, the concentrations of pigment, EPS and enzymes rose 3 to 30 times. These results highlighted that certain carbon sources and salinities could induce Chlorella sp. to produce EPS and enzymes for pollutant co-metabolism and also for revenue-raising potential.
Vu, HP, Nguyen, LN, Lesage, G & Nghiem, LD 2020, 'Synergistic effect of dual flocculation between inorganic salts and chitosan on harvesting microalgae Chlorella vulgaris', ENVIRONMENTAL TECHNOLOGY & INNOVATION, vol. 17.
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Vu, HP, Nguyen, LN, Zdarta, J, Nga, TTV & Nghiem, LD 2020, 'Blue-Green Algae in Surface Water: Problems and Opportunities', Current Pollution Reports.
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© 2020, Springer Nature Switzerland AG. Purpose of Review: Cyanobacteria, commonly known as blue-green algae, are often seen as a problem. Their accumulation (bloom) in surface water can cause toxicity and aesthetic concerns. Efforts have been made in preventing and managing cyanobacterial blooms. By contrast, purposeful cultivation of cyanobacteria can create great opportunities in food, chemical and biofuel applications. This review summarises the current stage of research and the socio-economic impacts associated with both the problems and opportunities induced from the presence of cyanobacteria in surface water. Recent Findings: Insightful knowledge of factors that trigger cyanobacterial blooms has allowed for the development of prevention and control strategies. Advanced technologies are utilised to detect, quantify and treat cyanobacterial biomass and cyanotoxins in a timely manner. Additionally, understanding of cyanobacterial biochemical properties enables their applications in food and health industry, agriculture and biofuel production. Researchers have been able to genetically modify several cyanobacterial strains to obtain a direct pathway for ethanol and hydrogen production. Summary: Cyanobacterial blooms have been effectively addressed with advances technologies and cyanobacterial research. However, this review identified a knowledge gap regarding cyanotoxin synthesis and the relevant environmental triggers. This information is essential for developing measures to prevent cyanobacterial blooms. Additionally, this review affirms the promising opportunities that cyanobacteria offer in the food, cosmetics, pigments and agriculture. Biofuel production from cyanobacterial biomass presents an immense potential but is currently constrained by the cultivation process. Thus, future research should strive to achieve effective mass harvesting of cyanobacterial biomass and obtain a profound understanding of cyanotoxin production.
Vu, MT, Vu, HP, Nguyen, LN, Semblante, GU, Johir, MAH & Nghiem, LD 2020, 'A hybrid anaerobic and microalgal membrane reactor for energy and microalgal biomass production from wastewater', Environmental Technology and Innovation, vol. 19.
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© 2020 Elsevier B.V. In the concept of a circular economy, wastewater is no longer waste but a resource for water, energy and nutrients. In this study, a hybrid system containing an anaerobic membrane bioreactor (AnMBR) and a microalgal membrane reactor (MMR) was developed to harvest energy, nutrients, and microalgal biomass from food and agribusiness industrial wastewater. The AnMBR removed over 97% of chemical oxygen demand (COD) and generated 4.7 ± 0.15 L (n=80) of biogas equivalent to 2.4 kWh kg−1 COD (feed) d−1. Through anaerobic metabolism, the microorganism in AnMBR generated NH4+ and PO43− -rich effluent. Their effluent concentrations were 1.9 and 1.4 times of that in the influent, respectively. NH4+ and PO43−-rich effluent was directly used (i.e. without filtration or sterilization) to culture microalgae Chlorella vulgaris in the MMR. . Microalgal biomass production reached up to 700 mg/L after 6 days of operation and nutrient removal rates of above 75% were achieved. However, biomass production and nutrient removal declined towards the end of experiment. The generated biomass was completely harvested using cationic polyacrylamide at the dose of 36 mg g−1 dry weight. Overall, the AnMBR has great potential to produce energy. Future research is needed to intensify the microalgal growth (e.g. genetic modification of strains, addition of plant hormones) in the MMR for continuous operation of the hybrid system.
Wang, Y, Wang, D, Yi, N, Li, Y, Ni, B-J, Wang, Q, Wang, H & Li, X 2020, 'Insights into the toxicity of troclocarban to anaerobic digestion: Sludge characteristics and methane production.', Journal of hazardous materials, vol. 385, pp. 121615-121615.
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Triclocarban (TCC), as the most typical antibacterial agent, is widely discovered in many ecological environment, especially in sludge. However, so far, no studies have reported the effect of TCC exposure on the properties of excess sludge. Therefore, in this study, TCC's toxicities to waste activated sludge (WAS) were analyzed by investigating the variation of physicochemical properties of sludge. It was found that TCC exposure has no effect on sludge pH, while it facilitated organic substances release from sludge, e.g. dissolved organic matter (DOM), protein and polysaccharide, which caused an increase of sludge reduction and changed the structure of functional groups and surface morphology of sludge. Moreover, we explored the effect of TCC on anaerobic digestion of WAS and found methane production was seriously inhibited by TCC. The related mechanism tests had illustrated that TCC exposure did not affect the hydrolysis process, but promoted the acidification and acetogenesis, and importantly inhibited the methanogenesis process. Methanogenic community was further evaluated and observed that the presence of TCC could vary the microbial community of methanogens with the abundance of aceticlastic methanogens increasing and hydrogenotrophic methanogens decreasing. These findings reached in this study would widen the understanding scope for TCC's toxicity to WAS.
Wei, W, Guo, W, Ngo, HH, Mannina, G, Wang, D, Chen, X, Liu, Y, Peng, L & Ni, BJ 2020, 'Enhanced high-quality biomethane production from anaerobic digestion of primary sludge by corn stover biochar', Bioresource Technology, vol. 306.
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© 2020 Elsevier Ltd This study conducted batch and continuous tests to reveal the feasibility of corn stover biochar on improving anaerobic digestion of primary sludge (PS). Dosing biochar (1.82, 2.55 and 3.06 g/g Total Solids (TS)) in digester improved methane content increasing from 67.5% to 81.3–87.3% and enhanced methane production by 8.6–17.8%. Model analysis indicated that biochar accelerated PS hydrolysis and enhanced methane potential of PS. The mechanistic studies showed that biochar enhanced process stability provided by strong buffering capacity and alleviated NH3 inhibition. In continuous test over 116 days, the volatile solids (VS) destruction in the biochar-dosed digester increased by 14.9%, resulting in a 14% reduction in the volume of digestate for disposal. Biochar changed microbial community in an expected direction for anaerobic digestion. This work suggests that biochar technology would apply to co-digestion of WAS and PS to maximize the energy recovery and sludge reduction from the two sludge streams.
Wei, W, Wu, L, Liu, X, Chen, Z, Hao, Q, Wang, D, Liu, Y, Peng, L & Ni, B-J 2020, 'How does synthetic musks affect methane production from the anaerobic digestion of waste activated sludge?', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 713.
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Wu, L, Peng, L, Wei, W, Wang, D & Ni, B-J 2020, 'Nitrous oxide production from wastewater treatment: The potential as energy resource rather than potent greenhouse gas.', Journal of hazardous materials, vol. 387, pp. 121694-121694.
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Nitrous oxide (N2O), produced from wastewater treatment, is a potent greenhouse gas and has become a global concern in recent years. However, N2O has also been commonly used as a powerful oxidant for energy generation. As such, an increasing effort has been devoted to explore the energy potential of N2O from wastewater treatment processes recently. Nevertheless, the holistic knowledge on energy recovery from nitrogen in wastewater is still lacking for facilitating its further development. Striving for sustainable wastewater treatment, this review paper aimed to give the up-to-date status on several essential aspects regarding the N2O recovery as an energy resource rather than emission as a greenhouse gas, including energy production via N2O decomposition, main biotic N2O production sources, the potential bioprocesses used for N2O recovery, and the possible N2O harvesting strategies. We then put forward perspectives for N2O recovery and future challenges to improve our understanding of the energy generation, microbial processes involved and harvesting approaches in order to potentially achieve sustainable wastewater treatment via N2O recovery.
Wu, S-L, Sun, J, Chen, X, Wei, W, Song, L, Dai, X & Ni, B-J 2020, 'Unveiling the mechanisms of medium-chain fatty acid production from waste activated sludge alkaline fermentation liquor through physiological, thermodynamic and metagenomic investigations', WATER RESEARCH, vol. 169.
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Xie, F, Li, L, Sun, X, Hu, T, Song, K, Giesy, JP & Wang, Q 2020, 'A novel Mg(OH)2 binding layer-based DGT technique for measuring phosphorus in water and sediment', Environmental Science: Processes and Impacts, vol. 22, no. 2, pp. 340-349.
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© 2020 The Royal Society of Chemistry. Diffusive gradients in thin films (DGT) have gained wide attention for in situ measurement of reactive phosphorus species (PO4) in natural water, sediments and potentially soils. In this study, a novel Mg(OH)2 binding gel was formed using magnesium hydroxide obtained by in situ hydration of calcined magnesium oxide. Laboratory scale experiments showed that the novel Mg(OH)2 gel had a homogeneous dispersion of fine particles of Mg(OH)2 with a particle size of 2-5 μm. With 10 mL of 2.0 mol L-1 NaOH as the eluting agent, the optimal elution efficiency of PO4 on the Mg(OH)2 gel was 72 ± 5%. There were linear relationships between the accumulated PO4 mass and the applied PO4 concentration (0.1 to 20 mg P per L), time (0 to 24 h) and temperature (22 to 40 °C). The capacity of the Mg(OH)2 binding layer was determined to be 99.5 μg P per disc. Tests in synthetic seawater, Chaohu Lake and Yihai Pond confirmed that Mg(OH)2-DGT was able to accurately measure phosphorus up to 10 days. This was indicated by the good agreements between the concentrations measured by DGT (CDGT) technology and by an ex situ chemical method in solution (Csoln), with a CDGT/Csoln ratio between 0.91 and 1.09.
Xu, B, Ahmed, MB, Zhou, JL & Altaee, A 2020, 'Visible and UV photocatalysis of aqueous perfluorooctanoic acid by TiO2 and peroxymonosulfate: Process kinetics and mechanistic insights', CHEMOSPHERE, vol. 243.
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Xu, B, Zhou, JL, Altaee, A, Ahmed, MB, Johir, MAH, Ren, J & Li, X 2020, 'Improved photocatalysis of perfluorooctanoic acid in water and wastewater by Ga2O3/UV system assisted by peroxymonosulfate', CHEMOSPHERE, vol. 239.
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Xu, D-S, Xu, X-Y, Li, W & Fatahi, B 2020, 'Field experiments on laterally loaded piles for an offshore wind farm', MARINE STRUCTURES, vol. 69.
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Xu, Q, Liu, X, Yang, G, Wang, D, Wu, Y, Li, Y, Huang, X, Fu, Q, Wang, Q, Liu, Y, Li, X & Yang, Q 2020, 'Norfloxacin-induced effect on enhanced biological phosphorus removal from wastewater after long-term exposure', Journal of Hazardous Materials, vol. 392.
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© 2020 Elsevier B.V. In this study, long-term experiments were performed under synthetic wastewater conditions to evaluated the potential impacts of norfloxacin (NOR) (10, 100 and 500 μg/L) on enhanced biological phosphorus removal (EBPR). Experimental result showed that long-term exposure to 10 μg/L NOR induced negligible effects on phosphorus removal. The presence of 100 μg/L NOR slightly decreased phosphorus removal efficiency to 94.41 ± 1.59 %. However, when NOR level further increased to 500 μg/L, phosphorus removal efficiency was significantly decreased from 97.96 ± 0.8 5% (control) to 82.33 ± 3.07 %. The mechanism study revealed that the presence of 500 μg/L NOR inhibited anaerobic phosphorus release and acetate uptake as well as aerobic phosphorus uptake during long-term exposure. It was also found that 500 μg/L NOR exposure suppressed the activity of key enzymes related to phosphorus removal but promoted the transformations of intracellular polyhydroxyalkanoate and glycogen. Microbial analysis revealed that that the presence of 500 μg/L NOR reduced the abundances of polyphosphate accumulating organisms but increased glycogen accumulating organisms, as compared the control.
Yadav, S, Saleem, H, Ibrar, I, Naji, O, Hawari, AA, Alanezi, AA, Zaidi, SJ, Altaee, A & Zhou, J 2020, 'Recent developments in forward osmosis membranes using carbon-based nanomaterials', DESALINATION, vol. 482.
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Yan, X, Sun, J, Kenjiahan, A, Dai, X, Ni, B-J & Yuan, Z 2020, 'Rapid and strong biocidal effect of ferrate on sulfidogenic and methanogenic sewer biofilms', WATER RESEARCH, vol. 169.
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Yang, G, Zhang, N, Yang, J, Fu, Q, Wang, Y, Wang, D, Tang, L, Xia, J, Liu, X, Li, X, Yang, Q, Liu, Y, Wang, Q & Ni, B-J 2020, 'Interaction between perfluorooctanoic acid and aerobic granular sludge', WATER RESEARCH, vol. 169.
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Yang, J, Liu, X, Liu, X, Xu, Q, Wang, W, Wang, D, Yang, G, Fu, Q, Kang, Z, Yang, Q, Liu, Y, Wang, Q & Ni, B-J 2020, 'Enhanced dark fermentative hydrogen production from waste activated sludge by combining potassium ferrate with alkaline pretreatment.', The Science of the total environment, vol. 707, pp. 136105-136105.
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Alkaline pretreatment was demonstrated to be effective in the enhancement of hydrogen production. However, the sludge solubilization rate of alkaline pretreatment is still limited. This study reports a new strategy of K2FeO4 + pH 9.5 for sludge mesophilic anaerobic fermentation. Experimental results showed that the combination of K2FeO4/pH 9.5 pretreatment had a greater hydrogen yield than the individual K2FeO4 and pH 9.5. The maximum hydrogen yield was 19.2 mL per gram volatile suspended solids (VSS) under the optimal condition (0.02 g per gram total suspended solids K2FeO4 + pH 9.5). Kinetic analysis showed that the highest hydrogen production potential of 19.9 mL/g VSS was obtained in the combined reactor, which well fitted the first-order kinetic model (R2 = 0.9925). Besides, the fermentation type was mainly acetic and butyric in the combined reactor, which contributed to hydrogen production. Further analyses showed that the combined pretreatment reduced hydrogen sulfide yield, providing an environmentally friendly method to sludge treatment.
Yang, Y, Liu, Y, Fang, X, Miao, W, Chen, X, Sun, J, Ni, B-J & Mao, S 2020, 'Heterogeneous Electro-Fenton catalysis with HKUST-1-derived Cu@C decorated in 3D graphene network', CHEMOSPHERE, vol. 243.
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Yang, Y, Zang, Y, Hu, Y, Wang, XC & Ngo, HH 2020, 'Upflow anaerobic dynamic membrane bioreactor (AnDMBR) for wastewater treatment at room temperature and short HRTs: Process characteristics and practical applicability', Chemical Engineering Journal, vol. 383.
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© 2019 Elsevier B.V. An upflow anaerobic dynamic membrane bioreactor (AnDMBR) was set up for real domestic wastewater treatment at room temperature (20–25 °C) and short hydraulic retention time (HRT = 8 h, 4 h, 2 h, and 1 h). Following continuous operation for 93 days with stepwise decreased HRT, stable average chemical oxygen demand (COD) removal was achieved (between 77.3% and 70.6%) when HRT was reduced from 8 h to 4 h, then 2 h with flux varying from 22.5 to 90 L/m2·h. At these three HRTs, the rate of increase in trans-membrane pressure (TMP) was 0.4, 0.38, and 0.57 kPa/d, and average methane (CH4) production was 0.12, 0.10, and 0.08 L/g CODremoved, respectively. Furthermore, decreasing the HRT to 1 h resulted in less COD being removed (60.4%) and lower CH4 production (0.05 L/g CODremoved) as well as a faster rate of TMP increase (2.11 kPa/d). Various analytical methods were applied to characterize the morphology and composition of the dynamic membrane (DM) layers. Organic components analysis revealed that, with reduced HRT, there were apparent increases in soluble microbial products in the liquid phase and accumulation of tryptophan protein-like substances and aromatic protein-like substances in the DM layer, especially when the HRT was shortened to 1 h. Whilst the upflow AnDMBR proved applicable to wastewater treatment at room temperature with short HRTs, 2 h could be the HRT limit for maintaining stable operation.
Yao, M, Tijing, LD, Naidu, G, Kim, S-H, Matsuyama, H, Fane, AG & Shon, HK 2020, 'A review of membrane wettability for the treatment of saline water deploying membrane distillation', DESALINATION, vol. 479.
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Ye, Y, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Zhang, X, Zhang, J & Liang, S 2020, 'Nutrient recovery from wastewater: From technology to economy', Bioresource Technology Reports.
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© 2020 Elsevier Ltd The recovery of fertilizer-used nutrients from wastewater is a sustainable approach for wastewater management and helping social sustainability. This is especially the case given the strict discharge requirements and shortages existing in nutrients supply. Recognizing that wastewater is a very useful resource and the value of recycled nutrients has made researchers consider the recovery of nutrients from wastewater. This review described the current technologies used to recover nutrients in wastewater treatment and their mechanisms, including chemical methods, biological technologies, membrane systems and advanced membrane systems. Also, an economic analysis of these nutrient recovery systems was discussed and compared them in terms of positive and negative aspects. The economic feasibility of recovered nutrients was investigated. Finally, future perspectives expects some possible research directions regarding recovery system which can be more economically accessible for wastewater treatment, in which the osmotic membrane bioreactors (OMBR) and bioelectrochemical systems (BES)-based hybrid systems are highly recommended.
Ye, Y, Ngo, HH, Guo, W, Chang, SW, Nguyen, DD, Zhang, X, Zhang, S, Luo, G & Liu, Y 2020, 'Impacts of hydraulic retention time on a continuous flow mode dual-chamber microbial fuel cell for recovering nutrients from municipal wastewater', Science of The Total Environment, pp. 139220-139220.
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Zang, Y, Yang, Y, Hu, Y, Ngo, HH, Wang, XC & Li, YY 2020, 'Zero-valent iron enhanced anaerobic digestion of pre-concentrated domestic wastewater for bioenergy recovery: Characteristics and mechanisms', Bioresource Technology, vol. 310.
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© 2020 Elsevier Ltd Pre-concentrated domestic wastewater (PDWW) rich in organic matters can be a suitable substrate for anaerobic digestion (AD) towards holistic resource and bioenergy recovery. Micron zero-valent iron (ZVI) was applied in designed batch experiments during anaerobic treatment of PDWW to verify its roles in performance enhancement and associated mechanisms. In the selected range of food to microorganism (F/M) ratio, 0.5 gCOD/gMLVSS was most appropriate as biomethane production potential (BMP) of 0.275 L CH4/gCOD was obtained. The optimal ZVI dosage at fixed F/M of 0.5 was 6 g/L, further enhancing the BMP by 15.2%. Furthermore, ZVI improved the hydrolysis process (producing more soluble organics) and regulated acidification process (affecting volatile fatty acids distribution). No obvious impact on acetoclastic and hydrogenotrophic methanogenesis processes was noted with ZVI addition. ZVI based AD of the PDWW is promising for promoting the practical application of advanced domestic wastewater treatment strategy (pre-concentration plus anaerobic digestion).
Zhang, S, Ly, QV, Nghiem, LD, Wang, J, Li, J & Hu, Y 2020, 'Optimization and organic fouling behavior of zwitterion-modified thin-film composite polyamide membrane for water reclamation: A comprehensive study', Journal of Membrane Science, vol. 596.
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© 2019 Membrane fouling can hinder the widespread application of thin film composite (TFC) reverse osmosis (RO) for water treatment. This study evaluated a novel zwitterion-grafted TFC RO as a mean to address organic fouling for water reclamation. The membrane exhibited the best permeability at the grafting condition of 45 °C in 1 h. This modified membrane consistently possessed improved antifouling ability irrespective of organic foulants. Among individual foulants, surfactant Dodecyl Trimethyl Ammonium Chloride (DTAC) posed the worst fouling potential due to its low molecular weight and positive charge, whereas fouling induced by other substances were relatively analogous and minor. In the mixture of DTAC and proteins, the former played a key role in governing the membrane fouling. While, their interplay affected membrane fouling, the fouling extent varied upon the membrane materials. The extended Derijaguin, Landau, Verwey and Overbeek (xDLVO) theory was unable to fully describe the interactions between surfactant foulants and the membrane materials. The complementary use of quartz crystal microbalance with dissipation (QCM-D), otherwise, concurred the fouling potential and gave the plausible interpretation for fouling mechanisms by providing insightful information of foulant layer on the polyamide-coated sensor. This study provided critical insights of organic foulants’ behavior on TFC RO membrane and offered the promising industrial implication of the novel membrane.
Zhang, X, Song, Z, Hao Ngo, H, Guo, W, Zhang, Z, Liu, Y, Zhang, D & Long, Z 2020, 'Impacts of typical pharmaceuticals and personal care products on the performance and microbial community of a sponge-based moving bed biofilm reactor.', Bioresource Technology, vol. 295, pp. 122298-122298.
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Four lab-scale moving bed biofilm reactors (MBBRs) were built to treat simulated wastewater containing typical pharmaceuticals and personal care products (PPCPs). The efficiency in removing different PPCPs at different concentrations (1, 2 and 5 mg/L) and their effects on the performance of MBBRs were investigated. Results showed that the average removal efficiencies of sulfadiazine, ibuprofen and carbamazepine were 61.1 ± 8.8%, 74.9 ± 8.8% and 28.3 ± 7.4%, respectively. Compared to the reactor without PPCPs, the total nitrogen (TN) removal efficiency of the reactors containing sulfadiazine, ibuprofen and carbamazepine declined by 21%, 30% and 42%, respectively. Based on the microbial community analysis, increasing the PPCPs concentration within a certain range (<2 mg/L) could stimulate microbial growth and increase microbial diversity yet the diversity reduced when the concentration (5 mg/L) exceeded the tolerance of microorganisms. Furthermore the presence and degradation of different PPCPs resulted in a different kind of microbial community structure in the MBBRs.
Zhang, X, Zhang, Y, Ngo, HH, Guo, W, Wen, H, Zhang, D, Li, C & Qi, L 2020, 'Characterization and sulfonamide antibiotics adsorption capacity of spent coffee grounds based biochar and hydrochar', SCIENCE OF THE TOTAL ENVIRONMENT, vol. 716.
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Zhao, S, Dou, P, Song, J, Nghiem, LD, Li, XM & He, T 2020, 'Direct preparation of dialysate from tap water via osmotic dilution', Journal of Membrane Science, vol. 598.
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© 2019 Elsevier B.V. Preparation of dialysate for hemodialysis (or dialysis) requires dilution of the dialysis concentrate with purified water. Present practice contains two steps: first to purify water, and then water is transported to clinic to mix with the dialysate concentrate before treatment. As a new forward osmosis dialysis hybrid process, based on osmotic dilution, is evaluated for decentralized health care systems. A commercial cellulose triacetate (CTA) and a tailor-made thin film composite (TFC) polyamide FO membranes were examined. The rejection of salts in tap water by the FO membranes was investigated, and the real rejections of various ions as a function of permeate flux were well described by using a irreversible thermodynamic model. The hollow fiber TFC FO membrane showed higher water flux and lower reverse salt flux than the CTA membrane in diluting process. Both steric hindrance and electrostatic repulsion explained the rejection behavior of the membranes to the ions. Higher rejections of anions were obtained than cations, which was attributed to the anions selection characteristics of the membranes. No obvious foulings or scalings were observed in a relatively long time osmotic dilution process over 5 repeated cycles. The stable, high efficient osmotic dilution process in hemodialysis holds a strong promise in reducing the consumption of purified water or even eliminating the water purification step. This work provides a potentially new platform hemodialysis which can be portable and implementable away from major hospitals and major clinics.
Zheng, L, Price, WE, He, T & Nghiem, LD 2020, 'Simultaneous cooling and provision of make-up water by forward osmosis for post-combustion CO2 capture', Desalination, vol. 476.
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© 2019 This study evaluates the feasibility of forward osmosis (FO) for simultaneous post-combustion CO2 capture and make-up water provision using seawater and treated effluent as the feed. Three amine-based CO2 adsorbents (glycine, sodium glycinate, and monoethanolamine (MEA)) were used as draw solutes. A non-linear relationship between concentration of these adsorbents and conductivity (thus osmotic pressure) was observed. Glycine showed higher water flux and lower reverse salt flux and specific reverse salt flux than sodium glycinate and MEA in both membrane orientations, thus was selected for further investigations. A higher water flux but with the considerable flux decline were observed when active layer faced draw solution. In addition, temperature increase in draw solution could alter thermodynamic properties of glycine, resulting in an increase of reverse salt flux. Water flux increase was also observed due to diminishing concentrative internal concentration polarisation. Changes in water flux were insignificant when active layer faced feed solution even as temperature increased. Temperature increase was likely to aggravate the severity of dilutive internal concentration polarisation and offset the growth of osmotic pressure. Seawater could also be a potential source for simultaneous cooling and providing the make-up water, although the water flux was lower compared to treated effluent.
Zhou, X, Jin, W, Wang, Q, Guo, S, Tu, R, Han, SF, Chen, C, Xie, G, Qu, F & Wang, Q 2020, 'Enhancement of productivity of Chlorella pyrenoidosa lipids for biodiesel using co-culture with ammonia-oxidizing bacteria in municipal wastewater', Renewable Energy, vol. 151, pp. 598-603.
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© 2019 Elsevier Ltd As one of the most promising renewable energy, microalgal biodiesel has been widely studied worldwide. However, the low-efficiency of conventional microalgae cultivation procedures restrict the development of microalgae biodiesel production. Microalgal-bacterial symbiosis could both enhance the growth of algal-bacterial culture and promote the removal and conversion of wastewater nutrients. In this study, three strains of high-efficient heterotrophic ammonia-oxidizing bacteria JN1, FN3, and FN5 were screened from municipal wastewater treatment system with over 80% degradation rates of 50 mg/L ammonia-nitrogen (NH3–N) in 24 h. Among them, FN5, belonging to Kluyvera sp., had the optimum effect on enhancing growth of oil-rich microalga Chlorella pyrenoidosa. In stationary phase, the biomass and lipid content of Chlorella pyrenoidosa was14.8% and 13.6% higher than the blank control tests without FN5. In contrast, JN1 and FN3 failed to enhance the growth of Chlorella pyrenoidosa. After the cultivation of Chlorella pyrenoidosa-FN5 consortia in municipal wastewater, the degradation rate of NH3–N was up to 91% while the content of microalgae biomass and lipid attained 0.35 g/L and 39.0%. The Saturated fatty acids (SFAs), Monounsaturated fatty acids (MUFAs), and Polyunsaturated fatty acids (PUFAs) were 43.9, 37.1 and 19.0%, respectively, which had the potential for biodiesel production after pretreatment.
Zhu, Y, Ouyang, L, Zhong, H, Liu, J, Wang, H, Shao, H, Huang, Z & Zhu, M 2020, 'Closing the Loop for Hydrogen Storage: Facile Regeneration of NaBH4 from its Hydrolytic Product', Angewandte Chemie - International Edition, vol. 59, no. 22, pp. 8623-8629.
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© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Sodium borohydride (NaBH4) is among the most studied hydrogen storage materials because it is able to deliver high-purity H2 at room temperature with controllable kinetics via hydrolysis; however, its regeneration from the hydrolytic product has been challenging. Now, a facile method is reported to regenerate NaBH4 with high yield and low costs. The hydrolytic product NaBO2 in aqueous solution reacts with CO2, forming Na2B4O7⋅10 H2O and Na2CO3, both of which are ball-milled with Mg under ambient conditions to form NaBH4 in high yield (close to 80 %). Compared with previous studies, this approach avoids expensive reducing agents such as MgH2, bypasses the energy-intensive dehydration procedure to remove water from Na2B4O7⋅10 H2O, and does not require high-pressure H2 gas, therefore leading to much reduced costs. This method is expected to effectively close the loop of NaBH4 regeneration and hydrolysis, enabling a wide deployment of NaBH4 for hydrogen storage.