Aluminium smelter wastewater : groundwater fluoride fate

This study assessed the viability of utilising groundwater systems to manage Portland Aluminium's trade waste water stream. A mathematical groundwater model was created to assess laboratory and field results. Fluoride was modelled for spatio-temporal longevity in the system. All models indicate that fluoride will ultimately exit the site to the seaward boundary.

Properties of a carbon-fibre composite modified by electrospun poly (vinylidene fluoride)

The interlaminar toughening of a carbon-fibre reinforced composite by incorporation of electrospun polyvinylidene fluoride (PVDF) nanofibrous membranes was explored in this work. The nanofibres were electrospun directly onto commercial pre-impregnated carbon fibre materials under optimised conditions and PVDF was found to primarily crystallise in its β phase polymorphic form. There is strong evidence from DMTA analysis to suggest that a partial miscibility between the amorphous phases of the PVDF nanofibres and the epoxy exists. The improved plastic deformation at the crack tip after inclusion of the nanofibres was directly translated to a 57% increase in the mode II interlaminar fracture toughness (in-plane shear failure). Conversely, the fracture toughness in mode I (opening failure) was slightly lower than the reference by approximately 20%, and the results were interpreted from the complex micromechanisms of failure arising from the changes in polymorphism of the PVDF.

Granular Activated Carbon (GAC) adsorption in tertiary wastewater treatment : experiments and models

Wastewater treatment has always been a major concern in the developed countries. Over the last few decades, activated carbon adsorption has gained importance as an alternative tertiary wastewater treatment and purification process. In this study, granular activated carbon (GAC) adsorption was evaluated in terms of total organic carbon (TOC) removal from low strength synthetic wastewater. This paper provides details on adsorption experiments conducted on synthetic wastewater to develop suitable adsorption isotherms. Although the inorganics used in the synthetic wastewater solution had an overall unfavourable effect on adsorption of organics, the GAC adsorption system was found to be effective in removing TOC from the wastewater. This study showed that equation of state (EOS) theory was able to fit the adsorption isotherm results more precisely than the most commonly used Freundlich isotherm. Biodegradation of the organics with time was the most crucial and important aspect of the system and it was taken into account in determining the isotherm parameters. Initial organic concentration of the wastewater was the determining factor of the model parameters, and hence the isotherm parameters were determined covering a wide range of initial organic concentrations of the wastewater. As such, the isotherm parameters derived using the EOS theory could predict the batch adsorption and fixed bed adsorption results of the multi-component system successfully. The isotherm parameters showed a significant effect on the determination of the mass transfer coefficients in batch and fixed bed systems.

Study on the fouling phenomena of poly(vinylidene fluoride) (PVDF) membrane by protein and yeast

This sub-collection is the result of an investigation into the mechanism of organic fouling in membrane filtration processes. In this experiment, poly(vinylidene fluoride) (PVDF) membranes were used to filter two types of organic foulants, protein and yeast with a concentration of 50mg/l and 20 mg/l, respectively, from suspension in a dead-end filtration cell. These model foulants were stained with fluorescent dyes before filtration. This dataset contains a stack of images of the fouling layer on the PVDF membrane surface captured by a confocal laser scanning microscope (CLSM) and its associated acquisition software. This dataset would be useful to researchers who are investigating the membrane organic fouling mechanism so that new membrane materials and new anti-fouling surface treatment technologies can be developed for water and wastewater industry in the future.

Evaluating backwashing efficiency of poly(vinylidene fluoride) (PVDF) membrane fouled by protein and yeast

This collection is the result of an investigation into the backwashing efficiency of poly(vinylidene fluoride) (PVDF) membrane fouled by two types of organic foulants, protein and yeast. In this experiement, poly(vinylidene fluoride) (PVDF) membrane was used to filter those organic foulants from suspensions in a dead-end stirred cell. The organic foulants were stained with fluorescent dyes before filtration. After filtration, the PC membrane was backwashed. Consequently, a stack of images were captured from the fouling layers on the PVDF membrane surface using confocal laser scanning microscope (CLSM) and its associated image acquisition software. It contains image data of poly(vinylidene fluoride) (PVDF) membranes' fouling layer when two types of organic foulants (protein and yeast) present. By comparing with the same membrane without backwashing, the efficiency of backwashing was computed. This data collection would be useful to researchers who are evaluating the backwashing efficiency of PVDF membrane in order to optimize frequency and operational conditions of backwashing by membrane materials and by water.

Evaluating backwashing efficiency of poly(vinylidene fluoride) (PVDF) membrane fouled by yeast and sodium alginate

This collection is the result of an investigation into the backwashing efficiency of poly(vinylidene fluoride) (PVDF) membrane fouled by yeast and sodium alginate. In this experiement, poly(vinylidene fluoride) (PVDF) membrane was used to filter two types of organic foulants from suspensions in a dead-end stirred cell. The organic foulants including yeast and sodium alginate were stained with fluorescent dyes before filtration. After filtration, the PC membrane was backwashed. Consequently, a stack of images were captured from the fouling layers on the PVDF membrane surface using confocal laser scanning microscope (CLSM) and its associated image acquisition software. The data collection contains image data of poly(vinylidene fluoride) (PVDF) membranes' fouling layer when two types of organic foulants (yeast and sodium alginate) are present. By comparing with the same membrane without backwashing, the efficiency of backwashing was computed. The collection would be useful to researchers evaluating the backwashing efficiency of poly(vinylidene fluoride) (PVDF) membrane in order to optimize frequency and operational conditions of backwashing by membrane materials and by water.

Study on the fouling phenomena of poly(vinylidene fluoride) (PVDF) membrane by protein and sodium alginate

This sub-collection is the result of an investigation into the mechanism of organic fouling in membrane filtration processes. In this experiment, poly(vinylidene fluoride) (PVDF) membranes were used to filter two types of organic foulants, protein and sodium alginate with a concentration of 50mg/l and 40 mg/l, respectively, from suspension in a dead-end filtration cell. These model foulants were stained with fluorescent dyes before filtration. This dataset contains a stack of images of the fouling layer on the PVDF membrane surface captured by a confocal laser scanning microscope (CLSM) and its associated acquisition software. This dataset would be useful to researchers who are investigating the membrane organic fouling mechanism so that new membrane materials and new anti-fouling surface treatment technologies can be developed for water and wastewater industry in the future.