66 research outputs found

    A Multi Expert Decision Support Tool for the Evaluation of Advanced Wastewater Treatment Trains: A Novel Approach to Improve Urban Sustainability

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    This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Wastewater Treatment (WWT) for water reuse applications has been accepted as a strategic solution in improving water supplies across the globe; however, there are still various challenges that should be overcome. Selection of practical solutions is then required whilst considering technical, environmental, socio-cultural, and financial factors. In this study, a multi expert decision support tool that considers a variety of evaluation criteria is proposed to provide a ranking system for competing advanced WWT technologies in terms of their performance. Two scenarios of water reuse in the contexts of Brazil and Greece are defined, and evaluation is undertaken based on opinions of water reuse experts. The results prove that the tool would successfully facilitate rigorous and methodical analysis in evaluation of WWT technologies for water reuse applications with potential for use under various sets of evaluation criteria, WWT technologies and contexts

    Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota)

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    Compared to the higher fungi (Dikarya), taxonomic and evolutionary studies on the basal clades of fungi are fewer in number. Thus, the generic boundaries and higher ranks in the basal clades of fungi are poorly known. Recent DNA based taxonomic studies have provided reliable and accurate information. It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines. Recently, Tedersoo et al. (MycoKeys 13:1--20, 2016) accepted Aphelidiomycota and Rozellomycota in Fungal clade. Thus, we regard both these phyla as members in Kingdom Fungi. We accept 16 phyla in basal clades viz. Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota. Thus, 611 genera in 153 families, 43 orders and 18 classes are provided with details of classification, synonyms, life modes, distribution, recent literature and genomic data. Moreover, Catenariaceae Couch is proposed to be conserved, Cladochytriales Mozl.-Standr. is emended and the family Nephridiophagaceae is introduced

    Development and testing of surface-based and water-based-diffusion kinetic models for studying hydrolysis and biogas production from cow manure

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    The hydrolytic step is usually considered the rate limiting step in the biological conversion of ligno-cellulose material into biofuels. Current optimization approach attempts to understand the mechanism of hydrolysis in order to boost production. In this study, the development and testing of a surface-based and a water-based-diffusion kinetic model for modeling biogas production from cow manure was conducted using total solid (TS) loading ranging from 8 to 10% (TS) in batch reactors. Parameter estimation using solver function of the Microsoft Excel Tool Pak revealed that, the second order water diffusion model was superior in predicting biogas production with correlation coefficients ranging from 0.9977 to 0.9995. In addition, the initial surface permeability flux of water (Kspf0) into the organic biomass and fragmentation of particles were observed to be independent events elicited by the action C1 and Cx factors respectively. The initial surface permeability flux of water was observed to increase as solids concentration increased from 8 to 9%TS while, fragmentation constants decreased. Maximum initial surface permeability flux of water (1.78E-05 m3/m2/day) was observed at 9% (TS) with a simultaneous minimization in the fragmentation rate (0.13/day). For optimal production of biofuels, appropriate quantity of C1-factor, the degree of crystallinity and particle size may be critical for efficient conversion

    Water-energy-pollution nexus for growing cities

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    Most recognised global challenges of modern times are related to energy production and consumption. The trends of energy demand for a growing world population and global urbanisation have raised serious concerns, and they are often termed as "global challenges" that include climate change, pollution and demands of clean water, food and energy. In thematic debate of the 2013 UN General Assembly in New York on "Sustainable Development and Climate Change: Practical Solutions in the Energy-Water Nexus" it was highlighted that adequate attention should be given to the importance of inter-linkages between water and energy sectors in framing the post-2015 development agenda. In fact, the implications of energy consumption in the modern world go beyond these boundaries. Therefore we argue that there is a need for establishing a broader nexus - "water-energy-pollution" - where implications of energy production, related water consumption and environmental pollution (air and water) are embedded. The notion of this integrated nexus can play an important role in systemic appraisal of energy production and consumption in growing urban environments. © 2014 Elsevier B.V

    Calibration and validation of an extended ASM3 for long-term modelling in a submerged membrane bioreactor for municipal wastewater treatment

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    A large pilot-scale membrane bioreactor (MBR) with a conventional denitrification/nitrification scheme for municipal wastewater treatment has been modelled with an extended version of ASM3 available in the literature, according to which heterotrophic biomass growth occurs on both readily biodegradable COD and storage products. The model has been regularly calibrated by means of respirometric techniques and validated against experimental data of MLSS concentration in the biotank, effluent COD and nitrogen forms. The applied model was able to fairly predict the routinely monitored effluent quality (COD, NH4-N and NO3-N) and sludge production. The model appears to be suitable for improved biological process modelling of MBRs, leading to better process optimization of MBRs for municipal wastewater treatment

    Disinfection and removal performance for Escherichia coli and heavy metals by silver-modified zeolite in a fixed bed column

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    This study investigates the simultaneous removal of Escherichia coli and metals (Pb, Cd and Zn) in a continuous flow system and provides an insight into the mechanisms involved during bacterial cells kill when in contact with silver-modified zeolite. Results showed complete disinfection and metal removal at 570 min contact time, thereafter E. coli breakthrough followed by Cd and Zn at 1080 min. Due to the zeolite’s high selectivity for Pb removal, no breakthrough was observed up to 7920 min run time. Column performance was influenced by changes in flow rate and bed height, as breakthrough occurred at 240 min when the flow rate was increased from 2 to 5 mL/min and the bed height decreased from 1 to 0.5 cm. Morphological characterization of treated cells revealed extensive damage and synthesis of nano- and micro-sized silver particles as a part of their defence mechanism. The treated effluent was passed through a non-modified zeolite column with 98% silver recovery achieved. This study showed the capability of this system to simultaneously handle bacterial and heavy metals contamination while providing an insight into the mechanism of disinfection via complex E. coli-silver ion interactions that occur during treatment and demonstrating the potential of silver recovery for reuse

    Removal of organic micropollutants using membrane assisted processes: a review of recent progress

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    The health risk of organic micro pollutants in water is yet to be comprehensively established. However, the persistence of these pollutants in the environment as a result of continuous discharge even at trace concentrations is considered to pose major environmental concerns. Advance treatment methods such as membrane-assisted processes (MAPs) are potential technologies capable of removing a wide range of these organic micropollutants (OMPs) detected in water. Tight membranes as regards pore size are reported to be more efficient than loose membranes mainly because of the removal mechanism involved, which is mainly influenced by the properties of the membrane and the pollutants in relation to solute–solute and solute–membrane interaction. The study and application of membrane processes to water and wastewater treatment have grown significantly in the last decade. Membrane processes application is diverse and flexible enough to allow adaptation into other physicochemical processes. Integration and hybridization of membrane processes with other physicochemical processes and natural systems are becoming a more economical and sustainable option for removal of OMPs. Nevertheless, there are shortfalls in the industrial application of membrane-assisted technologies. This paper reviews and assesses the applicability of various MAPs applied for the removal of OMPs from water and wastewater streams
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