Abdul, JM, Vigneswaran, S, Shon, HK, Nathaporn, A & Kandasamy, J 2009, 'Comparison of granular activated carbon bio-sorption and advanced oxidation processes in the treatment of leachate effluent', Korean Journal of Chemical Engineering, vol. 26, no. 3, pp. 724-730.
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Altaee, A, Al-Rawajfeh, AE & Baek, YJ 2009, 'Application of Vibratory System to Improve the Critical Flux in Submerged Hollow Fiber MF Process', Separation Science and Technology, vol. 45, no. 1, pp. 28-34.
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Areerachakul, N, Kitiphatmontree, M, Kandasamy, J, Kus, B, Duangduen, C, Pivsa-Art, S & Vigneswaran, S 2009, 'Submerged Membrane System with Biofilter as a Treatment to Rainwater', Water, Air, & Soil Pollution: Focus, vol. 9, no. 5-6, pp. 431-438.
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Rainwater has been used as drinking water in Thailand for centuries especially in the rural parts and is accepted as an important water resource. From past to present, the quality of rainwater has changed with the landuse of the landscape, and its water quality is influenced by a diverse range of conditions such as the management of pollutant sources, the catchment condition, wind and meteorological conditions, and the location of rainwater collection points. In this study, the quality of rainwater collected off roofs at several locations was examined. Granular activated carbon (GAC) filtration was used as a pretreatment to microfiltration (MF) to remove the dissolved organic matter (DOC). After an initial adsorption period, the biofilm that formed on the GAC (biofilter) was found to remove DOC by up to 40%, 35%, and 15% for bed filter depths of 15, 10, and 5 cm, respectively. Biofilters also removed nitrate and phosphate by more than 80% and 35%. The hollow fiber membrane microfiltration with pore size of 0.1 μm was used to treat the effluent from biofiltration to remove the microorganisms/pathogens in the rainwater. Although there was no significant additional removal of DOC by MF, the biofilter removed all microorganisms. The use of biofilters as pretreatment to MF/UF could remove a higher amount of DOC, remove microorganisms, increase the membrane treatment efficiency, and reduce membrane fouling.
Aryal, R, Kandasamy, J, Vigneswaran, S, Naidu, R & Lee, SH 2009, 'Review of Stormwater Quality, Quantity and Treatment Methods Part 2: Stormwater: Quality Modelling', Environmental Engineering Research, vol. 14, no. 3, pp. 143-149.
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In this paper, review of stormwater quality and quantity in the urban environment is presented. The review is presented in three parts. This second part reviews the mathematical techniques used in stormwater quality modelling and has been undertaken by examining a number of models that are in current use. The important features of models are discussed.
Aryal, R, Lebegue, J, Vigneswaran, S, Kandasamy, J & Grasmick, A 2009, 'Identification and characterisation of biofilm formed on membrane bio-reactor', Separation and Purification Technology, vol. 67, no. 1, pp. 86-94.
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Experiments were conducted in a laboratory scale membrane bio-reactor (MBR) system equipped with a side stream flat sheet membrane. Six runs lasting different durations (2, 4, 6, 9, 15 and 20 days) were conducted at an aeration rate of 2 m3 h-1 m-2 to understand the temporal variation of chemistry of foulant that attached on the membrane surface. The foulant attached on the membrane surface was extracted with 0.5% (v/v) NaOH solution and the extract was analysed using fluorescent spectroscopy and size exclusion chromatography. Variation of low- and high-molecular weight substances with evolution of time was compared. The results showed that the nature of foulant changed with the evolution of time. Four runs conducted for a short duration (2, 4, 6 and 9 days), low-molecular weight substances were dominant in the foulant whereas for long duration runs (15 and 20 days), high-molecular weight substances were mainly observed. Moreover, the foulant close to the membrane surface contained mainly protein and soluble microbial by-products.
Aryal, RK, Lebegue, J, Shon, HK, Vigneswaran, S, Kandasamy, J & Grasmick, A 2009, 'Temporal variation of foulant characteristics in membrane bioreactor', DESALINATION AND WATER TREATMENT, vol. 6, no. 1-3, pp. 69-73.
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Many studies have been performed to analyse the influence of compounds present in different fractions of the membrane foulants. The aim of this study was to reveal the changing chemistry of compounds present in membrane foulant with the evolution of time. Membrane fouling in a side stream membrane bioreactor (MBR) reactor was investigated. Constant flux filtration was employed in an MBR operation. Air bubbles were injected at 2 m3 h1 m2 for six different durations (2, 4, 6, 9, 15 and 20 days) of MBR operation. The foulant on the membrane surface was extracted using NaOH solution (5%) and analysed using fluorescent spectroscopy. The spectra showed the changing chemistry of foulant with the evolution of time. It showed low molecular weight substances such as amino acids and small aromatic proteins were dominant in the foulant at the beginning of the experiment but its concentration decreased with time. On the other hand BOD5 type substances concentration increased with time from the beginning of the experiment up to 9 days and there after decreased. The concentration of larger molecular weight soluble microbial by-products increased with evolution of time. Air bubbles at two aeration rate of 1m3 h1m2 and 2 m3 h1 m2 were also injected from the bottom of the membrane tanks to produce shear stresses on the membrane surface during 5 days of MBR operation to compare the effect of aeration in fouling propensity.
Baird, AH, Bhagooli, R, Ralph, PJ & Takahashi, S 2009, 'Coral bleaching: the role of the host', TRENDS IN ECOLOGY & EVOLUTION, vol. 24, no. 1, pp. 16-20.
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Coral bleaching caused by global warming is one of the major threats to coral reefs. Very recently, research has focused on the possibility of corals switching symbionts as a means of adjusting to accelerating increases in sea surface temperature. Although symbionts are clearly of fundamental importance, many aspects of coral bleaching cannot be readily explained by differences in symbionts among coral species. Here we outline several potential mechanisms by which the host might influence the bleaching response, and conclude that predicting the fate of corals in response to climate change requires both members of the symbiosis to be considered equally. © 2008 Elsevier Ltd. All rights reserved.
Buxton, L, Badger, M & Ralph, P 2009, 'EFFECTS OF MODERATE HEAT STRESS AND DISSOLVED INORGANIC CARBON CONCENTRATION ON PHOTOSYNTHESIS AND RESPIRATION OF SYMBIODINIUM SP (DINOPHYCEAE) IN CULTURE AND IN SYMBIOSIS', JOURNAL OF PHYCOLOGY, vol. 45, no. 2, pp. 357-365.
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The influence of temperature and inorganic carbon (Ci) concentration on photosynthesis was examined in whole corals and samples of cultured symbiotic dinoflagellates (Symbiodinium sp.) using combined measurements from a membrane inlet mass spectrometer and chl a fluorometer. In whole corals, O2 production at 26°C was significantly limited at Ci concentrations below ambient seawater (∼2.2 mM). Further additions of Ci up to ∼10 mM caused no further stimulation of oxygenic photosynthesis. Following exposure to 30°C (2 d), net oxygen production decreased significantly in whole corals, as a result of reduced production of photosynthetically derived oxygen rather than increased host consumption. Whole corals maintained a rate of oxygen evolution around eight times lower than cultured Symbiodinium sp. at inorganic carbon concentrations <2 mM, but cultures displayed greater levels of photoinhibition following heat treatment (30°C, 2 d). Whole corals and cultured zooxanthellae differed considerably in their responses to Ci concentration and moderate heat stress, demonstrating that cultured Symbiodinium make an incongruous model for those in hospite. Reduced net oxygen evolution, in whole corals, under conditions of low Ci (<2 mM) has been interpreted in terms of possible sink limitation leading to increased nonphotochemical energy dissipation. The advantages of combined measurement of net gas exchange and fluorometry offered by this method are discussed. © 2009 Phycological Society of America.
Chanan, A, Kandasamy, J, Vigneswaran, S & Sharma, D 2009, 'A gradualist approach to address Australia's urban water challenge', Desalination, vol. 249, no. 3, pp. 1012-1016.
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There is growing consensus worldwide against the conventional centralised approach to water management, and a âsoft pathâ for water management has emerged as a sustainable alternative. A âsoft pathâ for water management emphasizes the optimization of end-use efficiency, small-scaled management systems, incorporates fit-for-purpose water use, and recommends the use of diverse, locally appropriate and commonly decentralised infrastructures. However, large-scale desalination plants are currently being built for almost all metropolitan centres in Australia to ensure water supply security. Unlike âsoft pathâ for water management, large-scale desalination plants embody the traditional urban water supply approach. In spite of knowledge and values relating to the water cycle having shifted towards âsoft pathâ, the old organisational framework is believed to be hindering its adoption. Perhaps, therefore major water utilities in recent times have opted for the ideologically easier option of large-scale desalination conforming to the existing framework, instead of choosing a âsoft pathâ for water management with potential for decentralised management. This paper critically reviews the urban water management direction in metropolitan Australia and puts forward a âgradualist approachâ. It incorporates a comprehensive non-potable water reuse program necessary to build the familiarity and trust in water reuse, as a first step before introducing the idea of potable reuse.
Chiemchaisr, C, Passananon, S, Ngo, HH & Vigneswaran, S 2009, 'Simultaneous removal of particles and dissolved organic matter in floating media filter for surface water treatment', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 109-114.
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This research investigated the performance of fl oating media fi lter in removing particles and dissolved organic matter from surface water. Pilot-scale study consists of fl oating plastic media pre-fi lter connected with either granular activated carbon (GAC) or sponge biological fi lter (BF) bed. In the fl oating plastic media fi lter, coagulation and fl occulation processes using poly-aluminum chloride (PACl) as coagulant at an optimum dose of 8 mg/L helped removing particles from raw water. The fl oating media fi lter was operated a fi ltration rate of 11 m3/m2.h whereas those in GAC and BF units were maintained at 2 m3/m2.h. Continuous operation for over 120 days gave 98% and 99% average removal effi ciencies of turbidity and UV254 in fl oating media fi lter in combination with GAC unit whereas and 78% and 52% removal effi ciencies of turbidity and UV254 removal were obtained in fl oating media fi lter in combination with BF. The removal of dissolved organic carbon in GAC and BF units reduced chlorine demand for disinfection by 29% and 14%. It could also reduce the sum of trihalomethane (THMs) ratio from 1.1 to 0.1 and 0.5 respectively.
Chinu, KJ, Johir, AH, Vigneswaran, S, Shon, HK & Kandasamy, J 2009, 'Biofilter as pretreatment to membrane based desalination: Evaluation in terms of fouling index', DESALINATION, vol. 247, no. 1-3, pp. 77-84.
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The removal of particulate matter and dissolved organic matter from seawater by the use of biofiltration was investigated. Granular activated carbon (GAC) and anthracite were used as biofilter media at two different filtration velocities. Filtrate quality was measured in terms of silt density index (SDI), modified fouling index (MFI) and turbidity removal. Reverse osmosis (RO) was used as a post-treatment. Both biofilters demonstrated similar fouling reduction behavior in terms of SDI and MFI. Fouling potential in terms of MFI values decreased to 10 s/L2 within the first 10â15 days of operation and kept constant up to the remaining experimental period of 55 days of operation for both GAC and anthracite biofilter. The filtrate turbidity was steady after 10 days and remained low at a value of 0.2â0.3 NTU and 0.28â0.31 NTU for anthracite and GAC biofilter, respectively. Furthermore, the headloss development was low and within 20 cm for biofilter operated at a low velocity of 5 m/h. A post-treatment of reverse osmosis after a pretreatment of GAC and anthracite biofilters showed a reduction in normalized flux decline (J/J0) from 0.22 to 0.12 and 0.35 to 0.21 during the first 20 h, respectively. The RO flux for seawater declined at a faster rate and continued even after 3 days when no pretreatment was provided.
Collier, CJ, Lavery, PS, Ralph, PJ & Masini, RJ 2009, 'Shade-induced response and recovery of the seagrass Posidonia sinuosa', JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY, vol. 370, no. 1-2, pp. 89-103.
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The effect of shading on the seagrass Posidonia sinuosa Cambridge et Kuo was investigated to identify mechanisms that prolong its survival during periods of low light and permit its subsequent recovery. We also tested whether the responses were consistent in plants growing at different depths. Shade treatments were low (LS; 70 - 100% of ambient Photosynthetic Photon Flux Density), medium (MS; 12 - 39%) and heavy (HS; 5 - 4%) at the shallow (3 - 4 m) site, whilst the deep (7 - 8 m) site had no HS treatment. HS at the shallow and MS at the deep site were below minimum light requirements (MLR) for the long-term survival of P. sinuosa. Physiological, morphological and growth attributes were repeatedly measured during 198 d of shade treatments and a subsequent 384 d recovery period at ambient PPFD. Shoot density declined by 82% within 105 d under HS treatment, though 6% of shoots remained after 198 d. We estimate that complete shoot loss in HS would have taken 2 years. Rhizome sugar concentrations declined to 32 - 52% of the controls at the end of the most severe shading treatments but after shoot loss, sugar concentrations declined more slowly or increased, suggesting a return to positive carbon balance. In the treatments below MLR, shading induced changes in physiological, morphological and growth characteristics, including reduced leaf length and width, reduced δ13C and photosynthetic adaptation to low light (increased α, reduced Ek and ETRmax), though not consistently. After removal of shading, photosynthetic characteristics became more typical of high light adaptation, possibly induced by greater light penetration through the thinned canopy, including reversal of the changes in α, Ek and ETRmax and induction of non-photochemical quenching. Carbohydrate concentrations increased to ambient concentrations within 115 d at ambient PPFD. Recovery of shoot density was slow, remaining significantly reduced in the MS and HS treatments after 384 d recovery. Shoot...
El Saliby, I, Okour, Y, Shon, HK, Kandasamy, J & Kim, IS 2009, 'Desalination plants in Australia, review and facts', DESALINATION, vol. 247, no. 1-3, pp. 1-14.
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Australia is the driest continent on earth and despite this the installed desalination capacity is still around 1% of the total world's desalination capacity. This paper reviews the main seawater issues considered in every desalination projectâthe history, the present situation and the future of desalination in Australia, the suitability of applying reverse osmosis (RO) and the project details of two desalination plants (Sydney and Perth). Ocean currents, seawater temperature and salinity are signifi cant indicators in the assessment of the feasibility of desalination as they aff ect the production costs, the maintenance frequency and the quality of the product water. Seawater reverse osmosis (SWRO) is the only type of desalination technology currently used or proposed for future large-scale desalination plants in Australia. Every capital city except Darwin has considered building at least one desalination plant as a means of providing water security after several years of unprecedented drought that has signifi cantly reduced dam storage levels. Perth was the fi rst major city to use desalinated water for drinking water supply and by early 2009 Sydney will be the second city. Thirteen other large-scale SWRO plants are being planned or proposed at several locations for the purpose of supplying drinking water.
El Saliby, IJ, Okour, YH, Shon, HK, Vigneswaran, S, Kandasamy, J & Kim, J-H 2009, 'Detailed Investigation on the Effect of Washing TiO2 Prepared from Tisalts Flocculated Wastewater Sludge', Journal of Advanced Oxidation Technologies, vol. 12, no. 2, pp. 194-201.
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AbstractIn this study, the effect of washing TiO
Fahnenstiel, G, Hong, Y, Millie, D, Doblin, M, Johengen, T & Reid, D 2009, 'Marine dinoflagellate cysts in the ballast tank sediments of ships entering the Laurentian Great Lakes', INTERNATIONAL ASSOCIATION OF THEORETICAL AND APPLIED LIMNOLOGY, VOL 30, PT. 7, PROCEEDINGS, vol. 30, no. 7, pp. 1035-1038.
Fang, F, Ni, B-J & Yu, H-Q 2009, 'Estimating the kinetic parameters of activated sludge storage using weighted non-linear least-squares and accelerating genetic algorithm', Water Research, vol. 43, no. 10, pp. 2595-2604.
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Fang, F, Ni, B-J, Li, X-Y, Sheng, G-P & Yu, H-Q 2009, 'Kinetic analysis on the two-step processes of AOB and NOB in aerobic nitrifying granules', Applied Microbiology and Biotechnology, vol. 83, no. 6, pp. 1159-1169.
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Fatahi, B, Khabbaz, H & Indraratna, B 2009, 'Parametric studies on bioengineering effects of tree root-based suction on ground behaviour', ECOLOGICAL ENGINEERING, vol. 35, no. 10, pp. 1415-1426.
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Using native vegetation to improve soil stiffness, stabilise slopes and control erosion is a rapidly evolving process. A theoretical model previously developed by the authors for the rate of tree root water uptake together with an associated numerical simulation is used to study the effects of a wide range of soil, tree, and atmospheric parameters on partially saturated ground. The influence of different parameters on the maximum initial rate of root water uptake is investigated through parametric and sensitivity analyses. Field measurements taken from previously published literature are compared with numerical predictions for validation. The rate of selected parameters such as potential transpiration and its distribution, suction at wilting point, the coefficient of permeability and the distribution of root length density are studied in detail. The analysis shows that the rate of potential transpiration increases the soil matric suction and ground settlement, while the potential transpiration rate has an insignificant effect on the distribution of soil suction. Root density distribution factors affect the size of the influence zone. Suction at the wilting point increases the soil matric suction and ground settlement, whereas the saturation permeability decreases the maximum soil matric suction generated. The analysis confirms that the most sensitive parameters, including the coefficients of the tree root system, the transpiration rate, the permeability of the soil and its suction at the wilting point should be measured or estimated accurately for an acceptable prediction of ground conditions in the vicinity of trees. © 2009 Elsevier B.V. All rights reserved.
Fu, Q, Wang, G, Lin, W & Huang, J 2009, 'One‐pot preparation of 3‐miktoarm star terpolymers via “click chemistry” and atom transfer nitroxide radical coupling reaction', Journal of Polymer Science Part A: Polymer Chemistry, vol. 47, no. 3, pp. 986-990.
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Fu, Q, Zhang, Z, Lin, W & Huang, J 2009, 'Single-Electron-Transfer Nitroxide-Radical-Coupling Reaction at Ambient Temperature: Application in the Synthesis of Block Copolymers', Macromolecules, vol. 42, no. 13, pp. 4381-4383.
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Gribben, PE, Wright, JT, O'Connor, WA, Doblin, MA, Eyre, B & Steinberg, PD 2009, 'Reduced performance of native infauna following recruitment to a habitat-forming invasive marine alga', OECOLOGIA, vol. 158, no. 4, pp. 733-745.
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Despite well-documented negative impacts of invasive species on native biota, evidence for the facilitation of native organisms, particularly by habitat-forming invasive species, is increasing. However, most of these studies are conducted at the population or community level, and we know little about the individual fitness consequences of recruitment to habitat-forming invasive species and, consequently, whether recruitment to these habitats is adaptive. We determined the consequences of recruitment to the invasive green alga Caulerpa taxifolia on the native soft-sediment bivalve Anadara trapezia and nearby unvegetated sediment. Initially, we documented the growth and survivorship of A. trapezia following a natural recruitment event, to which recruitment to C. taxifolia was very high. After 12 months, few clams remained in either habitat, and those that remained showed little growth. Experimental manipulations of recruits demonstrated that all performance measures (survivorship, growth and condition) were significantly reduced in C. taxifolia sediments compared to unvegetated sediments. Exploration of potential mechanisms responsible for the reduced performance in C. taxifolia sediments showed that water flow and water column dissolved oxygen (DO) were significantly reduced under the canopy of C. taxifolia and that sediment anoxia was significantly higher and sediment sulphides greater in C. taxifolia sediments. However, phytoplankton abundance (an indicator of food supply) was significantly higher in C. taxifolia sediments than in unvegetated ones. Our results demonstrate that recruitment of native species to habitat-forming invasive species can reduce growth, condition and survivorship and that studies conducted at the community level may lead to erroneous conclusions about the impacts of invaders and should include studies on life-history traits, particularly juveniles.
Grover, DP, Zhang, ZL, Readman, JW & Zhou, JL 2009, 'A comparison of three analytical techniques for the measurement of steroidal estrogens in environmental water samples', Talanta, vol. 78, no. 3, pp. 1204-1210.
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Research into the analysis and monitoring of steroidal estrogens has grown significantly over the last decade, resulting in the emergence of a range of applicable techniques. In this study, three popular techniques, gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the analysis of three highly potent steroidal estrogens in the aquatic environment have been compared. It has been observed that overall, the three techniques appear comparable in generating similar estrogen concentrations for river and effluent samples. Of the three techniques, the GC-MS technique is the simplest to operate, but fails to detect the estrogens at the lower-end of environmentally relevant concentrations. The tandem MS techniques are more selective than MS, and therefore able to detect lower concentration levels of the three steroidal estrogens of interest. However, the LC-MS-MS technique is more susceptible to matrix interferences for the analysis of samples, resulting in a reduction of the signal-to-noise ratio and a subsequent reduction in reliability and stability compared to GC-MS-MS. With the GC-MS-MS technique offering increased selectivity, the lowest limits of detection, and no false positive identification, it is recommended to be the preferred analytical technique for routine analysis of estrogens in environmental water samples. © 2009 Elsevier B.V. All rights reserved.
Guo, W, Ngo, H-H, Palmer, CG, Xing, W, Hu, AY-J & Listowski, A 2009, 'Roles of sponge sizes and membrane types in a single stage sponge-submerged membrane bioreactor for improving nutrient removal from wastewater for reuse', DESALINATION, vol. 249, no. 2, pp. 672-676.
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Sponge not only can reduce membrane fouling by means of mechanical cleaning and maintain a balance of suspended-attached microorganisms in submerged membrane bioreactor (SMBR), but also can enhance dissolved organic matter and nutrient removal. This study investigated the performance of three different sizes of sponge (S28â30/45R, S28â30/60R and S28â30/90R) associated with continuous aerated SMBR. A laboratory-scale single stage sponge-SMBR (SSMBR) showed high performance for removing dissolved organic matter (>96%) and PO4âP (>98.8), while coarse sponges such as S28â30/45R, S28â30/60R could achieve more than 99% removal of NH4âN. When three-size sponges (S28â30/45R, S28â30/60R and S28â30/90R) were mixed at a ratio of 1:1:1 and in conjunction with two kinds of membranes (0.1 μm hollow fiber and 2 μm nonwoven), the SSMBR system has proved its generic merits of superior treated effluent quality and less membrane fouling. The NH4âN and PO4âP removal were found excellent, which were more than 99.8% and over 99% respectively. Molecular weight distribution also indicated that major fractions of organic matter could be successfully removed by SSMBR.
Guo, W, Xing, W, Ngo, H, Hu, YA, Palmer, CG & Zhang, R 2009, 'Enhancement of Organics removal by an Integrated Nonwoven Media Biofiter-submerged Membrane Adsorption Hybrid System', Journal of Applied Membrane Science & Technology, vol. 9, no. 1, pp. 1-8.
Hao, X, Wang, Q, Zhang, X, Cao, Y & Mark Loosdrecht, CMV 2009, 'Experimental evaluation of decrease in bacterial activity due to cell death and activity decay in activated sludge', Water Research, vol. 43, no. 14, pp. 3604-3612.
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Hassan, MH, Kalam, MA, Mahlia, TMI, Aris, I, Nizam, MK, Abdullah, S & Ali, Y 2009, 'Experimental Test of a New Compressed Natural Gas Direct Injection Engine', Energy & Fuels, vol. 23, no. 10, pp. 4981-4987.
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HIBBERD, A, MASKAOUI, K, ZHANG, Z & ZHOU, J 2009, 'An improved method for the simultaneous analysis of phenolic and steroidal estrogens in water and sediment', Talanta, vol. 77, no. 4, pp. 1315-1321.
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This paper describes an improved method for the extraction and analysis of seven endocrine disrupting chemicals with wide-ranging polarities from water and sediments using gas chromatography-tandem mass spectrometry (GC-MS/MS). The analytes were 4-tert-octylphenol, 4-nonylphenol, bisphenol A, estrone, 17β-estradiol, 17α-ethynylestradiol and 16α-hydroxyestrone. The optimised GC-MS/MS method produces increased selectivity and sensitivity compared to GC-MS, with limit of detection ranging from 0.01 to 0.49 ng L-1 in water and from 0.05 to 0.14 ng g-1 in sediment. Extraction from aqueous samples was performed by solid-phase extraction (SPE) and from sediment samples by microwave-assisted extraction (MAE). The improved method for the clean-up of sediment extracts carried out by SPE enhanced EDC recovery (86-102%) while reducing matrix interference and sample drying time. Derivatisation of final sample extracts was achieved using N,O-bis(trimethylsilyl)trifluoroacetamide and pyridine, and their stability was enhanced by reconstituting the derivatised extracts with hexane. The method was validated by spiking experiments which showed good recovery and reproducibility. The method was applied to samples taken from the Medway estuary in Kent, UK, where non-conservative behaviour of EDCs was demonstrated. © 2008 Elsevier B.V. All rights reserved.
Hill, R, Ulstrup, KE & Ralph, PJ 2009, 'TEMPERATURE INDUCED CHANGES IN THYLAKOID MEMBRANE THERMOSTABILITY OF CULTURED, FRESHLY ISOLATED, AND EXPELLED ZOOXANTHELLAE FROM SCLERACTINIAN CORALS', BULLETIN OF MARINE SCIENCE, vol. 85, no. 3, pp. 223-244.
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Coral bleaching events are characterized by a dysfunction between the cnidarian coral host and the symbiotic dinoflagellate algae, known as zooxanthellae (genus Symbiodinium). Elevated temperature and intense light induce coral bleaching, where zooxanthellae are expelled from the host tissue. The primary cellular process in zooxanthellae which leads to coral bleaching is unresolved, and here, we investigated the sensitivity of the thylakoid membrane in a Symbiodinium culture and in genetically identified freshly isolated and expelled Symbiodinium cells. The fluorescence-temperature curve technique was used to measure the critical temperature (Tc) at which irreversible damage to the thylakoid membrane occurred. The accuracy of this technique was confirmed through the collection of scanning transmission electron micrographs which demonstrated the clear relationship between Tc and thylakoid membrane degradation. Analysis of 10 coral species with a diverse range of genetically distinct Symbiodinium communities showed a decline in Tc from summer to winter. A Symbiodinium culture and fragments of Pocillopora damicornis (Linnaeus, 1758) were exposed to a series of light and temperature treatments, where Tc increased from approximately 37 °C to 42 °C upon exposure to elevated temperature. Under bleaching conditions, the thermostability of the thylakoid membrane increased within 4 hrs by 5.1 °C, to a temperature far above bleaching thresholds, in both freshly isolated and photosynthetically competent zooxanthellae expelled from P. damicornis under these conditions. It is demonstrated that the thermostability of the thylakoid membrane increases in cultured, freshly isolated, and expelled zooxanthellae exposed to bleaching stress, suggesting it is not the primary site of impact during coral bleaching events.
Ho, DP, Vigneswaran, S & Ngo, HH 2009, 'Photocatalysis-membrane hybrid system for organic removal from biologically treated sewage effluent', SEPARATION AND PURIFICATION TECHNOLOGY, vol. 68, no. 2, pp. 145-152.
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The application of semiconductor photocatalysis in treating wastewater has attracted growing interest due to its complete mineralisation of organic matter. Furthermore, coupling of photocatalytic process with microfiltration provided considerable advantages over the conventional methods. In this study, the photocatalytic reactivity of the catalysts was assessed at different operating conditions. The results show that the dissolved organic carbon (DOC) content was halved at a concentration of 1.0 g/L of TiO2. With the addition of flocculant FeCl3, the oxidation process was significantly improved further by another 30%. The recovery of TiO2 upon photooxidation process was achieved by coupling the photocatalysis reactor with a low energy submerged membrane reactor. The results show superior DOC degradation of more than 80% by this hybrid system. Moreover, it was demonstrated that photosensitization with TiO2/UV could effectively reduce membrane fouling and enhance the permeate flux of the submerged membrane reactor. © 2009 Elsevier B.V. All rights reserved.
Hossain, FM, Murch, GE, Belova, IV & Turner, BD 2009, 'Electronic, optical and bonding properties of CaCO3 calcite', Solid State Communications, vol. 149, no. 29-30, pp. 1201-1203.
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Husnawan, M, Masjuki, HH, Mahlia, TMI & Saifullah, MG 2009, 'Thermal analysis of cylinder head carbon deposits from single cylinder diesel engine fueled by palm oil–diesel fuel emulsions', Applied Energy, vol. 86, no. 10, pp. 2107-2113.
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Indraratna, B, Rujikiatkamjorn, C, Vinod, J & Khabbaz, H 2009, 'A Review of Ballast Characteristics, Geosynthetics, Confining Pressures and Native Vegetation in Rail Track Stabilisation', Transport Engineering in Australia, vol. 12, no. 1, pp. 25-36.
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Given the increased demand for freight transport for the mining and agriculture industries, and for greater public transport via trains due to increased fuel costs, heavier cyclic loading on existing tracks is now inevitable. Construction of rail tracks requires appropriate ballast specification to increase stability and performance of railway tracks. This paper aims to demonstrate and discuss some major aspects in relation to stabilisation of ballasted rail tracks overlying soft formation soils using geocomposites, prefabricated vertical drains and native vegetation. The use of geocomposites (ie. bonded geogrid-geotextile layers) for enhancing the performance of fresh and recycled ballast is described, with the aim of achieving reduced track settlement, increased resilient modulus and decreased ballast degradation. The effects of increasing the confi ning pressure on rail track behaviour, particularly with regard to particle breakage, have been studied using large-scale laboratory tests under cyclic loads. An elastoplastic stress-strain constitutive model for ballast was developed at the University of Wollongong, incorporating the degradation of particles as a particular feature, was introduced by capturing the breakage of particles during shearing, and the effects of cyclic loading on particle degradation and plastic deformation. In addition, numerical simulation using discrete element method has been carried out an assembly of irregular particles to investigate the mechanism of ballast breakage and to quantify breakage in relation to the ballast particle size distribution.
Jahirul, MI, Saidur, R, Masjuki, HH, Kalam, MA & Rashid, MM 2009, 'Application of Artificial Neural Networks (ANN) for Prediction the Performance of a Dual Fuel Internal Combustion Engine', HKIE Transactions, vol. 16, no. 1, pp. 14-20.
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Javeed, MA, Chinu, K, Shon, HK & Vigneswaran, S 2009, 'Effect of pre-treatment on fouling propensity of feed as depicted by the modified fouling index (MFI) and cross-flow sampler-modified fouling index (CFS-MFI)', DESALINATION, vol. 238, no. 1-3, pp. 98-108.
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The effectiveness of different pretreatment on the fouling propensity of the feed was studied using synthetic wastewater. The fouling potential of the feed was characterized by the standard modified fouling index (MFI) and cross-flow sampler modified fouling index (CFSMFI). In CFSMFI, a cross-flow sampler was used to simulate the condition of a cross-flow filtration. The results indicated that the pretreatment such as flocculation with an optimum dose of 68 mg/l FeCl3 substantially reduced the fouling propensity of the feed. The standard MFI of flocculated wastewater was reduced by around 99% compared to that of the untreated wastewater. Similarly, the adsorption with powdered activated carbon (PAC) of 1 g/l reduced the standard MFI value to more than 99% compared to that of the untreated wastewater. The CFSMFI values were lower than the standard MFI values for both treated and untreated wastewater, suggesting that the standard MFI was overestimated. The overestimation of the standard MFI compared to that of the CFSMFI value was more than 99%. The effect of molecular weight distribution (MWD) of the foulants in the wastewater on the fouling propensity of the feed was investigated. The MWD was correlated with the MFI and CFSMFI indices. It yielded useful insights in understanding the effect of MW on MFI and CFSMFI and fouling propensity of the feed.
Jayed, MH, Masjuki, HH, Saidur, R, Kalam, MA & Jahirul, MI 2009, 'Environmental aspects and challenges of oilseed produced biodiesel in Southeast Asia', Renewable and Sustainable Energy Reviews, vol. 13, no. 9, pp. 2452-2462.
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Johir, AH, Khorshed, C, Vigneswaran, S & Shon, HK 2009, 'In-line flocculation-filtration as pre-treatment to reverse osmosis desalination', DESALINATION, vol. 247, no. 1-3, pp. 85-93.
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In this paper the performance of single and dual media filters with in-line flocculation have been examined as pretreatment to seawater reverse osmosis (SWRO). A comparison of filter performance was made between single medium filter (80 cm) consisting of sand or anthracite, and dual media filter consisting of sand (40 cm at the bottom) and anthracite (40 cm on top). Short term (6 hours) experiments were conducted with in-line coagulation followed by direct filtration. Filtration velocities of 5 m/h and 10 m/h were used. The performances of these filters were assessed in terms of turbidity removal, head loss build-up, and organic compound removal in terms of molecular weight distribution (MWD). The efficiency of the filter as pretreatment was evaluated in terms of silt density index (SDI) and modified fouling index (MFI). It was found that the turbidity removal was high and all the filters produced more or less same quality water. There was a slower buildup of head loss for coarser filter medium. A post treatment of reverse osmosis after an inline-flocculation-dual media filtration showed lower normalized flux decline (J/J0) (0.35 to 0.22 during the first 20 hours operation) while, seawater without any pretreatment showed steeper flux decline (0.18 to 0.11 at first 20 hours operation) in RO.
Johir, MAH, Lee, JJ, Vigneswaran, S, Kandasamy, J & Shaw, K 2009, 'Treatment of Stormwater using Fibre Filter Media', Water, Air, & Soil Pollution: Focus, vol. 9, no. 5-6, pp. 439-447.
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In this study, a high-rate fibre filter was used as a pre-treatment to stormwater in conjunction with in-line flocculation. The effect of operating the fibre filter with different packing densities (105, 115 and 125 kg/m3) and filtration velocities (20, 40, 60 m/h) with and without in-line flocculation was investigated. In-line flocculation was provided using 5, 10 and 15 mg/L of ferric chloride (FeCl3·6H2O). The filter performance was studied in terms of pressure drop (ÎP), solids removal efficiency, heavy metals (total) removal efficiency and total organic carbon (TOC) removal efficiency. It is found that the use of in-line flocculation at a dose of 15 mg/L improved the performance of fibre filter as measured by turbidity removal (95%), total suspended solids reduction (98%), colour removal efficiency (99%), TOC removal (reduced by 30â40 %) and total coliform removal (93%). The modified fouling index reduced from 750â950 to 12 s/L2 proving that fibre filter can be an excellent pre-treatment to membrane filtration that may be consider as post-treatment. The removal efficiency of heavy metal was variable as their concentration in raw water was small. Even though the concentration of some of these metals such as iron, aluminium, copper and zinc were reduced, others like nickel, chromium and cadmium showed lower removal rates
Johir, MAH, Vigneswaran, S & Kandasamy, J 2009, 'Deep bed filter as pre-treatment to stormwater', Desalination and Water Treatment, vol. 12, no. 1-3, pp. 313-323.
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This paper presents the results of experiments on the application of dual media and single media deep bed filters as pre-treatments to stormwater. In-line flocculation-filtration experiments were conducted with dual and single media filter. The single filter media (80 cm) consisted of either anthracite or sand, and the dual media filter consisted of sand (40 cm at the bottom) and anthracite (40 cm on top). Filtration velocities of 5 m/h, 10 m/h and 15 m/h were examined. The removal efficiency for turbidity, suspended solids and TOC was found to be 95%, 99% and 30â45% respectively at a flocculant dose of FeCl3 of 15 mg/L. The anthracite filter media showed a lower headloss development (26 cm, operated at 5 m/h filtration velocity with FeCl3 dose of 5 mg/L). The removal efficiency for nitrogen was lower than phosphorus which was relatively good (up to 50%). The removal efficiency for heavy metals such as Cd, Pb, Cr and Ni was found to be very low for all tested filtration systems because concentrations of these metals in the influent were also low. This filter can be used as a pretreatment to a membrane filter as the modified fouling index was reduced from 750 s/L2 (for stormwater) to 15 s/L2 (for filtered effluent). Detailed submerged membrane filter experiments conducted with pre-treated water showed that the membrane filter can be successfully be used as post-treatment to in-line flocculant-filter at a sustainable flux of 10 L/m2.h to remove the remaining solids and pathogens. An increase of air scouring in the membrane unit decreased the pressure development although it did not have any effect on increasing the critical flux beyond 10 L/m2.h.
Kalam, MA, Masjuki, HH, Redzuan, M, Mahlia, TMI, Fuad, MA, Mohibah, M, Halim, KH, Ishak, A, Khair, M, Shahrir, A & Yusoff, A 2009, 'Development and test of a new catalytic converter for natural gas fuelled engine', Sadhana, vol. 34, no. 3, pp. 467-481.
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Kwon, B, Shon, HK & Cho, J 2009, 'Investigating the relationship between model organic compounds and ultrafiltration membrane fouling', DESALINATION AND WATER TREATMENT, vol. 8, no. 1-3, pp. 177-187.
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The aims of this study were to investigate the fouling mechanisms of model organic compounds (MOCs) on two ultrafiltration membranes [composite regenerated cellulose (YM100) and polyethersulfone (PES)] and the relationship between fouling and membrane characteristics, flux decline, and the streaming potential (SP). Two alginic acids (polymer and dimmer, AA), abietic acid (AbA), colominic acid (CA), and N-acetylneuraminic acid (NA) were selected as MOCs to test their membrane fouling potential through flux decline and SP. The fouling caused by the two AAs, which contained many polysaccharides, was the highest among MOCs, but this fouling was external (solute deposition on the membrane surface) and reversible as polysaccharides did not strongly adsorb onto the YM100 and PES membranes. CA also caused external fouling of the two membranes; however, AbA caused internal (solute adsorption on the pores wall of membrane) and irreversible fouling of the PES membrane. NA, which contained amino sugars, exhibited very low fouling of both membranes. The hydrophilic YM100 membrane experienced less fouling than the hydrophobic PES membrane with all MOCs. The measurement of the SP using a modified dead-end filtration cell was employed to evaluate the flux decline due to MOCs.
Lee, BC, Kim, S, Shon, HK, Vigneswaran, S, Kim, SD, Cho, J, Kim, IS, Choi, KH, Kim, JB, Park, HJ & Kim, J-H 2009, 'Aquatic toxicity evaluation of TiO2 nanoparticle produced from sludge of TiCl4 flocculation of wastewater and seawater', JOURNAL OF NANOPARTICLE RESEARCH, vol. 11, no. 8, pp. 2087-2096.
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Flocculation using titanium tetrachloride (TiCl4) as a coagulant is an efficient and economical application because the flocculated sludge can be recycled to produce a valuable byproduct, namely titanium dioxide (TiO2) nanoparticles. However, toxicity of TiCl4 has not yet been assessed while it is used in water treatment. The aquatic toxicity of TiCl4 flocculation process was investigated to assess the environmental safety of the coagulant. D. magna and V. fischeri bioassays were carried out to evaluate the supernatant toxicity after TiCl4 flocculation. Artificial wastewater, biologically treated sewage effluent, and seawater were used to study the toxicity of TiCl4 flocculation. Results showed that supernatant toxicity was very low when TiCl4 flocculation was conducted (no observed effect concentration = 100 mg/L and lowest observed effect concentration = 150 mg/L exposed to D. magna and V. fischeri, respectively). Similarly, TiO2 nanoparticles recovered from wastewater and seawater flocculated sludge were also found to have low toxicity. The regenerated TiO2 nanoparticles indicated low toxicity values when compared to the commercial-TiO2 nanoparticle, P-25.
Lee, JJ, Johir, MAH, Chinu, KH, Shon, HK, Vigneswaran, S, Kandasamy, J, Kim, CW & Shaw, K 2009, 'Hybrid filtration method for pre-treatment of seawater reverse osmosis (SWRO)', DESALINATION, vol. 247, no. 1-3, pp. 15-24.
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Hybrid processes combining fi bre fi lter with deep bed fi ltration process such as (i) fi bre fi lter and sand fi lter, (ii) fi bre fi lter and anthracite and (iii) fi bre fi lter and dual media fi lter were investigated as pre- treatments to SWRO. Seawater was drawn from Chowder Bay, Sydney. The eff ect of diff erent pretreatment hybrid systems was investigated in terms of silt density index (SDI10), modifi ed fouling index (MFI), headloss across the fi lters and reduction in turbidity and dissolved organic carbon (DOC). The in-line fl occulation in fi bre fi lter improved the performance of the pretreatment hybrid system as measured by the MFI, SDI10, headloss, turbidity and DOC removal. The lowest SDI10 and MFI were found with a fi bre fi lter operated at a fi ltration velocity of 40 m/h followed by dual media fi lter operated at a fi ltration velocity of 5 m/h. The lowest headloss and turbidity was found with a fi bre fi lter operated at a fi ltration velocity of 40 m/hr followed by anthracite operated at a fi ltration velocity of 5 m/h. This system also gave an effl uent with the lowest DOC of 0.64 mg/L corresponding to a removal effi ciency of about 70%.
Listowski, A, Ngo, HH, Guo, WS, Vigneswaran, S & Palmer, CG 2009, 'Concepts towards a novel integrated assessment methodology of urban water reuse', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 81-92.
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Traditional supplies of large volumes of water and wastewater disposal technologies have offered a linear solution, thus intensifying environmental stress. In addition, provision of urban infrastructure especially any major augmentations are often the impractical or economically prohibitive. Urban water cycle should be viewed as an interactive and coordinated approach involving: Available water resources, Appropriate treatment technology producing fi t for purpose water quality, and Ascertaining long term balance between environmental, social and economic issues.
LIU, S-G, NI, B-J, WEl, L, TANG, Y & YU, H-Q 2009, 'Contact-Adsorption-Regeneration-Stabilization Process for the Treatment of Municipal Wastewater', Journal of Water and Environment Technology, vol. 7, no. 2, pp. 83-90.
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Liu, X-W, Yu, H-Q, Ni, B-J & Sheng, G-P 2009, 'Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment', BIOTECHNOLOGY IN CHINA I, vol. 113, pp. 275-303.
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Ngo, H-H & Guo, W 2009, 'Membrane fouling control and enhanced phosphorus removal in an aerated submerged membrane bioreactor using modified green bioflocculant', BIORESOURCE TECHNOLOGY, vol. 100, no. 18, pp. 4289-4291.
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This study aims at developing a modified green bioflocculant (GBF) for membrane fouling control and enhanced phosphorus removal in a conventional aerated submerged membrane bioreactor (SMBR) to treat a high strength domestic wastewater (primary sewage treated effluent) for reuse. The GBF was evaluated based on long-term operation of a lab-scale SMBR. These results showed that SMBR system could achieve nearly zero membrane fouling at a very low dose of GBF addition (500 mg/day) with less backwash frequency (2 times/day with 2-min duration). The transmembrane pressure only increased by 2.5 kPa after 70 days of operation. The SMBR could also remove more than 95% and 99.5% dissolved organic carbon and total phosphorus, respectively. From the respiration tests, it was evident that GBF not only had no negative impact on biomass but also led to high oxygen uptake rate (OUR) (>30 mg O2/L h) and stable specific oxygen uptake rate (SOUR). These results also indicated that GBF had no effect on nitrogen removal and nitrification process.
Ngo, HH, Chuang, H, Guo, WS, Ho, DP, Pham, TTN, Johnston, A, Lim, R & Listowski, A 2009, 'Resident's strategy survey on a new end use of recycled water in Australia', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 93-97.
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The concept of using recycled water for washing machine was introduced as a new end use. As there is a noticeable lack social research in understanding the general public perceptions of this application, the resident's strategy survey was carried out at some selective suburbs in Sydney with demographically based significant differences of general, gender, age, education, and property style and ownership. The survey indicates that the majority in the community considers the use of recycled water for washing machine is indispensable in view of continuing drought and the associated water shortages. Given safety assurance and demonstration, recycled water for washing machine has a considerable proportion within the responses. The general level of knowledge in community clearly understand that recycled water is more environmentally friendly option, whereas from cleanness and public health point of view, higher quality water is required to be reused in washing machine. Moreover, the residents reckon to have a small unit for pre-treatment (point of use) before recycled water entering washing machines might assure the quality and safety. The survey also shows the major concerns for a resident to use recycled water for washing machine are public health, water cleanness and washing machine durability. © 2009 Desalination Publications.
Nguyen, TV, Nguyen, TVT, Pham, TL, Vigneswaran, S, Ngo, HH, Kandasamy, J, Nguyen, HK & Nguyen, DT 2009, 'Adsorption and removal of arsenic from water by iron ore mining waste', Water Science and Technology, vol. 60, no. 9, pp. 2301-2308.
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There is a global need to develop low-cost technologies to remove arsenic from water for individual household water supply. In this study, a purified and enriched waste material (treated magnetite waste, TMW) from the Trai Cau's iron ore mine in the Thai Nguyen Province in Vietnam was examined for its capacity to remove arsenic. The treatment system was packed with TMW that consisted of 75% of ferrous-ferric oxide (Fe3O4) and had a large surface area of 89.7 m2/g. The experiments were conducted at a filtration rate of 0.05 m/h to treat groundwater with an arsenic concentration of 380 μg/L and iron, manganese and phosphate concentrations of 2.07 mg/L, 0.093 mg/L and 1.6 mg/L respectively. The batch experimental results show that this new material was able to absorb up to 0.74 mg arsenic/g. The results also indicated that the treatment system removed more than 90% arsenic giving an effluent with an arsenic concentration of less than 30 μg/L while achieving a removal efficiency of about 80% for Mn2 + and PO43−. This could be a promising and cost-effective new material for capturing arsenic as well as other metals from groundwater.
Nguyen, TV, Rahman, A, Vigneswaran, S, Ngo, HH, Kandasamy, J, Nguyen, DT, Do, TA & Nguyen, TK 2009, 'Arsenic removal by iron oxide coated sponge: treatment and waste management', WATER SCIENCE AND TECHNOLOGY, vol. 60, no. 6, pp. 1489-1495.
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One of the problems in drinking water that raises concern over the world is that millions of people still have to use arsenic-contaminated water. There is a worldwide need to develop appropriate technologies to remove arsenic from water for household and community water supply systems. In this study, a new material namely iron oxide coated sponge (IOCSp) was developed and used to remove arsenic (As) from contaminated groundwater in Vietnam. The results indicated that lOCSp has a high capacity in removing both As (V) and As (III). The adsorption capacity of IOCSp was up to 4.6 mg As/g IOCSp, showing better than many other materials. It was observed from a pilot study that a small quantity of IOCSp (180 g) could reduce As concentration of 480 μg/L in 1.5 m3 of contaminated natural water to below 40 μg/L. In addition, an exhausted IOCSp, containing a large amount of arsenic (up to 0.42 wt %) could safely be disposed through the solidification/stabilization with cement. Addition of fly ash also reduced the amount of arsenic in the leachate. © IWA Publishing 2009.
Nguyen, VT, Vigneswaran, S, Ngo, HH, Shon, HK & Kandasamy, J 2009, 'Arsenic removal by a membrane hybrid filtration system', DESALINATION, vol. 236, no. 1-3, pp. 363-369.
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Arsenic is a toxic semi-metallic element that can be fatal to human health. Membrane filtration can remove a number of contaminants from water, including arsenic. Removal of arsenic by membrane filtration is highly dependent on the species of arsenic and the properties of the membrane. The performance of the nanofilter is better for removing As(V) than As(III). About 57% of As(III) and 81% of As(V) was removed from 500 mg/L arsenic solutions by nanofiltration (NTR729HF, Nitto Denko Corp., Japan) of 700 molecular weight (MW) cutoff. The removal efficiency of microfiltration (MF) was much lower than that of nanofiltration (NF) due to its larger pore size. By comparison only 37% of As(III) and 40% of As(V) were removed by microfiltration (PVA membrane, Pure-Envitech, Korea). However, the removal efficiency of microfiltration was increased dramatically when a small amount of nanoscale zero valent iron (nZVI) was added. The removal efficiency by MF increased up to 90% with As(V) and 84% with As(III) when an amount of 0.1 g/L of nZVI was added into the arsenic solution.
Ni, B & Yu, H 2009, 'A thermodynamic analysis of the activated sludge process: Application to soybean wastewater treatment in a sequencing batch reactor', AIChE Journal, vol. 55, no. 10, pp. 2737-2745.
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AbstractA bioenergetic methodology was integrated with a modified activated sludge model No.1 (ASM1) to analyze the activated sludge process, with the treatment of soybean‐processing wastewater as an example. With the bioenergetic methodology established by McCarty and coworkers, the microbial yield was predicted and the overall stoichiometrics for biological reactions involving the key chemical and biological species in activated sludge were established. These obtained parameters were related to the ASM1 model, which was modified after coupling the biological reactions in activated sludge with electron balances. This approach was able to approximately describe the treatment of soybean wastewater by activated sludge in a sequencing batch reactor in terms of substrate utilization, biomass growth, and the elector acceptor consumption. Such an attempt provides useful information for accurate modeling of the complex activated sludge process. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Ni, B, Chen, Y, Liu, S, Fang, F, Xie, W & Yu, H 2009, 'Modeling a granule‐based anaerobic ammonium oxidizing (ANAMMOX) process', Biotechnology and Bioengineering, vol. 103, no. 3, pp. 490-499.
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AbstractA mathematical model was developed to describe the anaerobic ammonium oxidation (ANAMMOX) process in a granular upflow anaerobic sludge blanket (UASB) reactor. ANAMMOX granules were cultivated in the UASB reactor by seeding aerobic granules. The granule‐based reactor had a great N‐loading resistant capacity. The model simulation results on the 1‐year reactor performance matched the experimental data well. The yield coefficient for the growth and the decay rate coefficient of the ANAMMOX granules were estimated to be 0.164 g COD g−1 N and 0.00016 h−1, respectively. With this model, the effects of process parameters on the reactor performance were evaluated. Results showed that the optimum granule diameter for the maximum N‐removal should be between 1.0 and 1.3 mm and that the optimum N loading rate should be 0.8 kg N m−3 d−1. In addition, the substrate micro‐profiles in the ANAMMOX granules were measured with a microelectrode to explore the diffusion dynamics within the granules, and the measured profiles matched the predicted results well. Biotechnol. Bioeng. 2009;103: 490–499. © 2009 Wiley Periodicals, Inc.
Ni, B, Xie, W, Liu, S, Yu, H, Wang, Y, Gan‐Wang & Dai, X 2009, 'Modeling and simulation of the sequencing batch reactor at a full‐scale municipal wastewater treatment plant', AIChE Journal, vol. 55, no. 8, pp. 2186-2196.
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AbstractIn this work, we attempted to modify the Activated Sludge Model No.3 and to simulate the performance of a full‐scale sequencing batch reactor (SBR) plant for municipal wastewater treatment. The long‐term dynamic data from the continuous operation of this SBR plant were simulated. The influent wastewater composition was characterized using batch measurements. After incorporating all the relevant processes, the sensitivity of the stoichiometric and kinetic coefficients for the model was thoroughly analyzed prior to the model calibration. The modified model was calibrated and validated with the data from both batch‐ and full‐scale experiments. Model predictions were compared with routine data in terms of chemical oxygen demand, NH4+‐N and mixed liquid volatile suspended solids in the SBR, combined with batch experimental data under different conditions. The model predictions match the experimental results well, demonstrating that the model is appropriate to simulate the performance of a full‐scale wastewater treatment plant even operated under perturbation conditions. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Ni, B-J, Fang, F, Rittmann, BE & Yu, H-Q 2009, 'Modeling Microbial Products in Activated Sludge under Feast−Famine Conditions', Environmental Science & Technology, vol. 43, no. 7, pp. 2489-2497.
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Ni, B-J, Fang, F, Xie, W-M, Sun, M, Sheng, G-P, Li, W-H & Yu, H-Q 2009, 'Characterization of extracellular polymeric substances produced by mixed microorganisms in activated sludge with gel-permeating chromatography, excitation–emission matrix fluorescence spectroscopy measurement and kinetic modeling', Water Research, vol. 43, no. 5, pp. 1350-1358.
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Ni, B-J, Xie, W-M, Liu, S-G, Yu, H-Q, Wang, Y-Z, Wang, G & Dai, X-L 2009, 'Granulation of activated sludge in a pilot-scale sequencing batch reactor for the treatment of low-strength municipal wastewater', Water Research, vol. 43, no. 3, pp. 751-761.
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Ni, B-J, Zeng, RJ, Fang, F, Xu, J, Sheng, G-P & Yu, H-Q 2009, 'A Novel Approach to Evaluate the Production Kinetics of Extracellular Polymeric Substances (EPS) by Activated Sludge Using Weighted Nonlinear Least-Squares Analysis', Environmental Science & Technology, vol. 43, no. 10, pp. 3743-3750.
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Nisola, GM, Cho, ES, Shon, HK, Tian, D, Chun, DJ, Gwon, EM & Chung, WJ 2009, 'Cell Immobilized FOG-Trap System for Fat, Oil, and Grease Removal from Restaurant Wastewater', Journal of Environmental Engineering, vol. 135, no. 9, pp. 876-884.
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Cell immobilized lipase-producing bacteria on three different matrices were incorporated in a fat-, oil-, and grease (FOG) trap system for restaurant wastewater treatment. During a 16-day laboratory-scale experiment for the treatment of synthetic FOG wastewater containing soybean oil, no significant difference (two-tailed t test at 95% confidence interval) in the FOG removal between two systems was observed at FOG influent < 1,000 mg/L. However, the typical trap showed lower FOG removal efficiency than the matrix-based system when the influent FOG concentration was increased to >= 5,000 mg/L. In addition, the matrix-based trap system was able to sustain a stable high FOG removal, with < 100 mg/L effluent, even at 10,000 mg/L influent FOG. Based on FOG heights measured and mass balance calculations, 97.4 and 99.5% of the total FOG load for 16 days were removed in a typical trap and matrix-based system, respectively. About 93.6% of the removal in the matrix-based was accounted to biodegradation. The 30-day full-scale operations demonstrated a distinguishably better performance in the matrix-based system (92.7 +/- 9.06% of 1,044.8 +/- 537.27 mg FOG/L) than in the typical trap system (74.6 +/- 27.13% of 463.4 +/- 296.87 mg FOG/L) for the treatment of barbeque restaurant wastewater. Similarly, matrix-based system revealed higher chemical oxygen demand removal (85.9 +/- 11.99%) than the typical trap system (60.4 +/- 31.26%). Characterizations of the influent, emulsified, adsorbed and effluent FOG indicated that straight saturated fatty acids constituted the cause of clogging problems in the FOG-trap and piping system.
Okour, Y, El Saliby, I, Shon, HK, Vigneswaran, S, Kim, J-H, Cho, J & Kim, IS 2009, 'Recovery of sludge produced from Ti-salt flocculation as pretreatment to seawater reverse osmosis', DESALINATION, vol. 247, no. 1-3, pp. 53-63.
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In this study, titanium tetrachloride (TiCl4), titanium sulfate (Ti(SO4)2) and ferric chloride (FeCl3) flocculation as a pretreatment to seawater reverse osmosis (SWRO) were investigated. Their ability to remove turbidity, seawater organic matter (SWOM) and controlling the feed water quality of SWRO was evaluated. Flux decline of SWRO and membrane autopsy were studied. Titanium dioxide (TiO2) produced from sludge after Ti-salt fl occulation was characterized in terms of particle structure and photocatalytic activity. A hybrid system of fl occulation followed by granular activated carbon (GAC) filtration was employed to remove the suspended micro-flocs after diff erent fl occulations. The optimum dose of 10 mg/L TiCl4 and FeCl3 were used. The turbidity removal for the three coagulants was marginal at different doses at pH 6 and 8. Flocculation followed by GAC fi ltration signifi cantly reduced the turbidity values from 1.5 NTU to about 0.35 NTU using TiCl4 and 0.40 using FeCl3. Silt density index (SDI15) was also decreased from 5.0 to 4.2 and 4.7, respectively. Removal of dissolved organic carbon (DOC), colour and UV absorbance after TiCl4 and FeCl3 flocculation followed by GAC fi ltration was found to be eff ective and similar. TiO2 produced from sludge showed very high photocatalytic activity under UV-irradiation. Acetaldehyde was completely removed after 45 min photocatalytic reaction
Petrou, K, Doblin, M, Hassler, C & Ralph, P 2009, 'MULTIPLE STRESSORS ON ANTARCTIC MICROALGAE IMPACTS OF SEASONAL FREEZING AND MELTING OF SEA-ICE', PHYCOLOGIA, vol. 48, no. 4, pp. 106-106.
Ren, T, Mu, Y, Ni, B & Yu, H 2009, 'Hydrodynamics of upflow anaerobic sludge blanket reactors', AIChE Journal, vol. 55, no. 2, pp. 516-528.
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AbstractThe hydrodynamic characteristics of upflow anaerobic sludge blanket (UASB) reactors were investigated in this study. A UASB reactor was visualized as being set‐up of a number of continuously stirred tank reactors (CSTRs) in series. An increasing‐sized CSTRs (ISC) model was developed to describe the hydrodynamics of such a bioreactor. The gradually increasing tank size in the ISC model implies that the dispersion coefficient decreased along the axial of the UASB reactor and that its hydrodynamic behavior was basically dispersion‐controlled. Experimental results from both laboratory‐scale H2‐producing and full‐scale CH4‐producing UASB reactors were used to validate this model. Simulation results demonstrate that the ISC model was better than the other models in describing the hydrodynamics of the UASB reactors. Moreover, a three‐dimensional computational fluid dynamics (CFD) simulation was performed with an Eulerian‐Eulerian three‐phase‐fluid approach to visualize the phase holdup and to explore the flow patterns in UASB reactors. The results from the CFD simulation were comparable with those of the ISC model predictions in terms of the flow patterns and dead zone fractions. The simulation results about the flow field further confirm the discontinuity in the mixing behaviors throughout a UASB reactor. © 2008 American Institute of Chemical Engineers AIChE J, 2009
Sharif, AO, Merdaw, AA, Al-Bahadili, H, Al-Taee, A, Al-Aibi, S, Rahal, Z & Derwish, GAW 2009, 'A new theoretical approach to estimate the specific energy consumption of reverse osmosis and other pressure-driven liquid-phase membrane processes', Desalination and Water Treatment, vol. 3, no. 1-3, pp. 111-119.
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Shon, HK, Kim, SH, Vigneswaran, S, Ben Aim, R, Lee, S & Cho, J 2009, 'Physicochemical pretreatment of seawater: fouling reduction and membrane characterization', DESALINATION, vol. 238, no. 1-3, pp. 10-21.
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The pretreatment of raw seawater is necessary to minimize the organic fouling of seawater reverse osmosis (SWRO) membranes. To predict the membrane fouling of the pretreated seawater, the modified fouling index (MFI) with ultrafiltration (UF) was investigated in terms of molecular weight distribution (MWD) and membrane characterization. The study was conducted with seawater drawn from Collioure, France. The concentration of total dissolved solids was 32,760 mg/L. The molecular weight (MW) of the initial seawater organic matter (SWOM) ranged from about 14160 Da to 280 Da. FeCl3 flocculation removed the majority of SWOM, while PAC adsorption could not remove the lowest MW fraction of organic matter (1110, 750 and 280 Da). The UF membranes with 30 kDa and 100 kDa MW cut-off removed the majority of of organic matter corresponding to the peaks 14,160 Da and 6560 Da in MWD. The MFI values obtained when using UF membranes of 30 kDa and 100 kDa with MF pretreatment were 19,700 s/L2 and 31,000 s/L2, respectively. The MFI values after pretreatments of FeCl3 flocculation and PAC adsorption significantly decreased to 6900 s/L2 and 6700 for 30 kDa UF and to 2300 s/L2 and 2500 s/L2 for 100 kDa UF, respectively. Some relation does exist for both membranes between the MFIUF values and Spb values obtained during the first peiod of filtration (pore blocking). The pore blocking zone significantly decreased after flocculation and adsorption pretreatment. This suggests that the pore blocking can be used as an indicator to predict membrane propensity. The detailed membrane characterization on the clean and fouled membrane surface after MFIUF experiments was made in terms of contact angle, zeta potential, functional group and microscopy.
Shon, HK, Puntsho, S, Chon, K, Aryal, R, Vigneswaran, S, Kim, IS & Cho, J 2009, 'A study on the influence of ionic strength on the elution behaviour of membrane organic foulant using advanced separation tools', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 38-45.
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Although membrane technology has become a reliable and viable alternative for water and wastewater treatment, membrane fouling is a serious challenge. In this case study, we report application of different techniques to extract foulant from the hollow fibre membrane and char-acterize the foulant into various components of organic, inorganic and different fractions. The organic foulant was subjected to high-pressure size exclusion chromatography (HPSEC) and flow field-flow fractionation (FlFFF) analysis to study the influence of ionic strength on its elution behaviour using NaCl and CaCl2 as carrier solutions. It was observed that an increase in ionic strength delayed the elution time of both the organic foulant and the Na-salt of Polysterene sulphone (PSS) with HPSEC. However, no such effect was observed with FlFFF analysis. Such study is significant because the characteristics of the membrane organic foulant are believed to be influenced by the carrier ionic conditions and pH and, therefore their subsequent interaction with the membrane and membrane fouling process. However with FlFFF, whether the influence of carrier ionic strength is limited to certain type of ionic carriers or certain groups of natural organic matter is a scope for further research. © 2009 Desalination Publications.
Shon, HK, Vigneswaran, S, Kandasamy, J, Kim, J-B, Park, HJ, Choi, SW & Kim, J-H 2009, 'Preparation of titanium oxide, iron oxide, and aluminium oxide from sludge generated from Ti-salt, Fe-salt and Al-salt flocculation of wastewater', JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY, vol. 15, no. 5, pp. 719-723.
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In this study, the settled floc (sludge) produced by aluminum sulfate (Al2(SO4)3), ferric chloride (FeCl3) and titanium tetrachloride (TiCl4) flocculation was recycled with a novel flocculation process, which has a significant potential to the lower cost of waste disposal, protect the environment and public health and yield economically useful by-products. Three coagulants removed 70% of organic matter in synthetic wastewater. The settled floc was incinerated in the range from 100 8C to 1000 8C. Alumina (Al2O3), hematite (Fe2O3), titanium oxide (TiO2) which are the most widely used metal oxides were produced from the wastewater sludge generated by the flocculation in wastewater with Al2(SO4)3, FeCl3 and TiCl4, respectively. TiO2 particles produced from the sludge consisted of the large amount of nano size particles. Hematite (Fe2O3) and grattarolaite (Fe3 (PO4)O3 or Fe3PO7) included the majority of micro size (40%) particles. Alumina (Al2O3) also consisted of micro size (40%). Due to TiO2 usefulness of the application, detailed characterisation of TiO2 after calcination at different temperatures were investigated in terms of X-ray diffraction, energy dispersive X-ray, surface area and photoactivity.
Shon, HK, Vigneswaran, S, Kandasamy, J, Zareie, MH, Kim, JB, Cho, DL & Kim, J-H 2009, 'Preparation and Characterization of Titanium Dioxide (TiO2) from Sludge produced by TiCl4 Flocculation with FeCl3, Al-2(SO4)(3) and Ca(OH)(2) Coagulant Aids in Wastewater', SEPARATION SCIENCE AND TECHNOLOGY, vol. 44, no. 7, pp. 1525-1543.
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In this study, TiCl4 coagulant together with coagulant aids such as FeCl3, Al2(SO4)3, and Ca(OH)2 were investigated to improve the photoactivity of titanium dioxide (TiO2) produced from sludge and to increase the resulting low pH value. After TiCl4 flocculation with three coagulant aids, the settled floc (sludge) was incinerated at 600°C to produce TiO2 doped with Fe, Al, and Ca elements. Fe-, Al-, and Ca-doped TiO2 was characterized in terms of structural, chemical, and photo-electronic properties. All the coagulant aids used together with Ti-salt flocculation effectively increased the pH values. The surface area of TiO2-WO (without any coagulant aids), Fe/TiO2, Al/TiO2, and Ca/TiO2 was 122 m2/g, 77 m2/g, 136 m2/g and 116 m2/g, respectively. The TiO2-WO, Fe/TiO2, Al/TiO2, and Ca/TiO2 was found to be of anatase phase. The XRD pattern on the Fe/TiO2 included an additional peak of hematite (α-Fe2O3). The majority of gaseous acetaldehyde with TiO2-WO and Ca/TiO2 for photocatalytic activity was completely removed within 40 minutes under UV irradiation.
Shon, HK, Vigneswaran, S, Zareie, MH, Ben Aim, R, Lee, E, Lee, J, Cho, J & Kim, IS 2009, 'Physico-chemical pretreatment to seawater reverse osmosis (SWRO): organic characterization and membrane autopsy', DESALINATION, vol. 236, no. 1-3, pp. 282-290.
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In this study, different pretreatment methods such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), powdered activated carbon (PAC) adsorption and ferric chloride (FeCl3) flocculation were evaluated in terms of their capability in removing seawater organic matter (SWOM) and the characteristics of the foulants on the seawater reverse osmosis (SWRO) membranes. A detailed experiment with a crossflow SWRO filtration unit was conducted with SR membrane (MWCO 100 Da) at 60 bar with seawater (conductivity = 48.9 mS/cm) drawn from south-western Korea. The SWOM removal by UF, NF, PAC adsorption and FeCl3 flocculation was 20.3, 28.9, 46 and 23.3%, respectively. SWOM used in this study predominantly consisted of small size organic matter (<1000 Da). A large amount of the hydrophobic fraction present in SWOM was removed by PAC adsorption. The SDI5min significantly decreased from 12.7 (without any pretreatment) to 3.2 (MF), 1.3 (UF), 1.0 (NF) and 4.4 (PAC adsorption). RO filtration of seawater with and without pretreatment showed significant flux decline (normalized flux decline (J/J0) = 0.17 ± 0.02) within 20-h operation. The elemental analyses made on the RO surface after direct RO filtration showed that the relative fraction of the carbon decreased, while sodium (Na), magnesium (Mg), chlorine (Cl) and iron (Fe) elements were found in the foulants extracted from the fouled membrane surface. The average roughness of the clean membrane surface was 41.5 nm. After MF and UF pretreatment, the roughness slightly increased to 54.8 and 55.6 nm, respectively. On the other hand, without any pretreatment, with PAC adsorption and with FeCl3 flocculation, the roughness increased up to 69.7, 66.4 and 110 nm, respectively. It can be concluded that the pretreatment by MF and UF could relatively preserve the RO membrane surface.
Simon, A, Nghiem, LD, Le-Clech, P, Khan, SJ & Drewes, JE 2009, 'Effects of membrane degradation on the removal of pharmaceutically active compounds (PhACs) by NF/RO filtration processes', Journal of Membrane Science, vol. 340, no. 1-2, pp. 16-25.
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Smith, P & Vigneswaran, S 2009, 'Effect of backwash and powder activated carbon (PAC) addition on performance of side stream membrane filtration system (SSMFS) on treatment of biological treatment effluent', Desalination and Water Treatment, vol. 11, no. 1-3, pp. 46-51.
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In this study, a pilot scale Side Stream Membrane Filtration System (SSMFS) was used to demonstrate the need for optimization of backwash conditions and the addition of PAC. Through an investigation of the amount of fouling each cycle that can be restored through backwashing over a short-term, a good operating point for long-term operation was developed. Periodic removal of 1.5% of the PAC slurry mixture (7.5 L out of 500 L) and PAC replacement (15 g/d) was found to have a positive impact on the reduction of membrane fouling. © 2009 Desalination Publications.
Strom, D, Ralph, PJ & Stauber, JL 2009, 'Development of a Toxicity Identification Evaluation Protocol Using Chlorophyll-a Fluorescence in a Marine Microalga', ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, vol. 56, no. 1, pp. 30-38.
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Growth inhibition bioassays with the microalga Nitzschia closterium have recently been applied in marine Toxicity Identification Evaluation (TIE) testing. However, the 48-h test duration can result in substantial loss of toxicants over time, which might lead to an underestimation of the sample toxicity. Although shorter-term microalgal bioassays can minimize such losses, there are few bioassays available and none are adapted for marine TIE testing. The acute (5-min) chlorophyll-a fluorescence bioassay is one alternative; however, this bioassay was developed for detecting herbicides in freshwater aquatic systems and its suitability for marine TIE testing was not known. In this study, a chlorophyll-a fluorescence bioassay using the marine microalga Isochrysis galbana was able to detect contaminants other than herbicides at environmentally relevant concentrations and tolerated the physical and chemical manipulations needed for a Phase I TIE. Phase I TIE procedures were successfully developed using this chlorophyll-a fluorescence bioassay and used to identify all classes of contaminants present in a synthetic mixture of known chemical composition. In addition, TIEs with both the acute fluorescence bioassay and the standard growth inhibition bioassay identified the same classes of toxicants in a sample of an unknown complex effluent. Even though the acute chlorophyll-a fluorescence end point was less sensitive than the chronic cell division end point, TIEs with the chlorophyll-a fluorescence bioassay provided a rapid and attractive alternative to longer-duration bioassays. © 2008 Springer Science+Business Media, LLC.
Thompson, PA, Baird, ME, Ingleton, T & Doblin, MA 2009, 'Long-term changes in temperate Australian coastal waters: implications for phytoplankton', MARINE ECOLOGY PROGRESS SERIES, vol. 394, pp. 1-19.
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A ∼60 yr physical and chemical data set from 4 coastal stations around Australia plus remotely sensed SeaWiFS and phytoplankton taxonomic data were used to evaluate the temporal and spatial variation in phytoplankton ecology. The most consistent trend observed at all stations was a long-term increase in surface salinity of ∼0.003 ± 0.0008 psu yr-1. All stations showed positive trends in temperature, with the fastest surface warming (0.0202°C yr-1 over 60 yr) in the western Tasman Sea. Long-term trends in warming and stratification were more evident in some months and were not well characterized by annual averages. There was no general pattern of increasing stratification (0 to 50 m); only some stations and a few months showed significant changes. Long-term trends in surface nitrate and phosphate concentrations were either not significant (3 instances) or positive (5 instances) and were up to 6.1 nM phosphate yr-1. A pronounced decline in silicate was evident at the 3 east coast stations, with concentrations falling by as much as 58 nM yr-1 over the last ∼30 yr. The western Tasman Sea experienced a ∼50% decline in the growth rate and biomass of the spring bloom from 1997 to 2007, while other sites showed significant temporal variability in chlorophyll a that was associated with the Southern Oscillation Index (SOI). Diatoms tended to dominate the microplankton, especially during periods of low stratification. In conclusion, the physical, chemical and biological properties of Australian temperate waters have changed considerably over the last 60 yr in response to variation in the SOI and the strengthening East Australian Current. © Inter-Research 2009.
Tijing, LD, Kim, HY, Lee, DH, Kim, CS & Cho, YI 2009, 'Use of an Oscillating Electric Field to Mitigate Mineral Fouling in a Heat Exchanger', Experimental Heat Transfer, vol. 22, no. 4, pp. 257-270.
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Wu, D, Liu, X, Wang, L, Wang, L, Xu, M, Sun, T, Yang, Z & Zhou, J 2009, 'QSARs on the Depuration Rate Constants of Polycyclic Aromatic Hydrocarbons in Elliptio complanata', QSAR & Combinatorial Science, vol. 28, no. 5, pp. 537-541.
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AbstractUsing quantum chemical descriptors and partial least squares (PLS) regression, a quantitative structure–activity relationships (QSARs) model was developed to predict the depuration rate constants (kd) of polycyclic aromatic hydrocarbons (PAHs) for mussels, Elliptio complanata (log kd=−2.1406+0.6013DE−2.0767×10−3 Mw−0.201EHOMO). With a high cumulative cross‐validated regression coefficient value (Q$\rm{ {_{cum}^{2}}}$) of 0.927 and low standard deviation (SD) of 0.065, the model obtained by the training set shows a good predictive ability, and it is validated to be robust by predicting the test set. Among 20 quantum chemical descriptors, the dielectric energy (DE), the molecular weight (Mw), and the highest occupied molecular orbital energy (EHOMO) are the key descriptors governing the logkd values in the model. Increase in the DE or decrease in the Mw values leads to the increase in logkd, indicating the van der Waals interactions and steric hindrance effect on the depuration process. Decrease in the EHOMO values results in increasing the logkd values, implying important roles the molecular orbital energies may play in the biological depuration of...
Yanti, PAA & Mahlia, TMI 2009, 'Considerations for the selection of an applicable energy efficiency test procedure for electric motors in Malaysia: Lessons for other developing countries', Energy Policy, vol. 37, no. 9, pp. 3467-3474.
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Zhang, R, Khorshed, C, Vigneswaran, S & Kandasamy, J 2009, 'Submerged microfiltration coupled with physcio-chemical processes as pretreatment to sea water desalination', Desalination and Water Treatment, vol. 11, no. 1-3, pp. 52-57.
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In this study, the critical fl ux of the submerged membrane system was experimentally evaluated when it was used for seawater with and without pre-treatment. In this study, different processes such as fl occulation with ferric chloride (FeCl3) and different doses of PAC adsorption were used as a pre-treatment. The pretreatment of fl occulant of 2 mg/L of FeCl3 and adsorption with the dose of 1 g/L PAC showed an improvement in the critical fl ux from 5 L/m2.h to 6.7 L/m2.h and 13.3 L/m2.h respectively. The performance of these pretreatments was also determined in terms of modifi ed fouling index using ultrafi lter membrane (UF-MFI). UF-MFI and SDI indicated that PAC adsorption was a better pretreatment than fl occulation for the seawater used in this study. Molecular weight distribution (MWD) of seawater organic matter was also examined after different pretreatments. MWD of the raw seawater was mainly in the range from 1510 to 130 Da. It is observed that FeCl3 fl occulation and PAC adsorption as pretreatments partially removed the organic matter of 1510 Da and 130Da respectively
Zhao, B-H, Yue, Z-B, Ni, B-J, Mu, Y, Yu, H-Q & Harada, H 2009, 'Modeling anaerobic digestion of aquatic plants by rumen cultures: Cattail as an example', Water Research, vol. 43, no. 7, pp. 2047-2055.
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Zhou, JL, Zhang, ZL, Banks, E, Grover, D & Jiang, JQ 2009, 'Pharmaceutical residues in wastewater treatment works effluents and their impact on receiving river water', Journal of Hazardous Materials, vol. 166, no. 2-3, pp. 655-661.
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Various pharmaceutical residues are being discharged from wastewater treatment works (WTW) effluents, the impact of which on river water quality is of high relevance to environmental risk assessment. The concentrations of eleven pharmaceutical compounds were determined in three WTWs in England, and the river Ouse receiving effluents from Scaynes Hill WTW. Results show that five compounds propranolol, sulfamethoxazole, carbamazepine, indomethacine and diclofenac were detected in all wastewater and river water samples, with carbamazepine showing the highest concentrations (up to 2336 ng L-1) in WTW influent. Different compounds were removed to different extent in the WTWs, varying from 43 to 92%, with the highest performance obtained by the WTW with tertiary treatment (sand filtration). The pharmaceutical residues from Scaynes Hill WTW were eventually discharged into the river Ouse, causing an elevation in their concentrations downstream of the outfall. This was confirmed by the good agreement between measured concentrations and those predicted by a simple dilution model. © 2008 Elsevier B.V. All rights reserved.
