Project #1. Detection of chemical by-products of water recycling technologies

Project Leaders: A/Prof. Richard Stuetz, Dr Stuart Khan, Dr James McDonald

The threat to sustainable drinking water supplies by climate uncertainty and population growth requires innovative management of water resources. Water recycled from sewerage or stormwater is set to play an increasingly important role in future management systems.

Advanced water treatment plants employ an array of physical and chemical methods to ensure the destruction of pathogens and toxic chemicals. One important process uses ozone, a highly reactive molecular form of oxygen. Ozone is very effective at degrading organic chemicals. However, the process leads to the formation other chemical byproducts, most of which have not currently been identified.

One suspected class of byproducts are ‘epoxides’. Many epoxides are toxic to DNA and some are suspected carcinogens. Work has recently been undertaken in the development of a sensitive analytical method for epoxides in water. It is now time to undertake the first ever field trial to determine whether these compounds will be measurable in recycled water after ozone treatment.

Working alongside other researchers, the student would conduct field sampling at a water treatment plant using ozonation. They will gain practical laboratory experience in the extraction, chemical derivatisation and instrumental analysis of micro-pollutants. Samples will be analysed using gas chromatography-mass spectrometry enabling the detection and quantification of any measurable epoxides in water. This field trial will be a key step in the validation of the new analytical method.

Contact and further information: s.khan@unsw.edu.au
jamesmcdonald@unsw.edu.au

Project #2: Contaminant Generation and Transport in Coastal Acid Sulfate Soil Systems

Project Leaders: Dr Richard Collins and Professor David Waite

Much of the coastline of Australia and the southeast Asian region are underlain by sediments that contain iron pyrite which generates acid on disturbance and resulting exposure to air. Acid conditions result in dissolution of minerals and generation of high concentrations of aluminium and iron in pore waters which can be transported to estuarine and coastal waters with resultant deleterious ecological impacts. In this project, the ToR candidate will work with a team of research students and staff in studies of acid and metals transport from coastal subsurface environments to adjacent waterways in both laboratory and field investigations. Both geochemical and geophysical aspects of the systems will be characterised and their impact on contaminant transport clarified. The opportunity exists for the candidate to participate in either (or both) experimental and computational aspects of the problem.

Contact and further information: d.waite@unsw.edu.au; richard.collins@unsw.edu.au

Project #3: Investigation of Factors Inducing the Growth of Harmful Algal Blooms in Coastal Waters

Project Leaders: Dr Andrew Rose, Dr Shikha Garg and Professor David Waite

It is now clear that coastal development has a significant impact on the ecology of coastal waters including effects such as the stimulation of blooms of harmful (toxic) algae. One of the key drivers to enhanced growth is the supply of the trace nutrient iron in forms that are more bioavailable than would otherwise be the case. In this project, the candidate will investigate the means by which particular organisms render iron available for consumption and will investigate the impacts of particular land management practices on the rate and extent of iron uptake and organism growth rate. The candidate will work with a team of research staff and students in the School of Civil and Environmental Engineering with emphasis on studies under well-defined conditions which are amenable to modelling of the key processes controlling elemental uptake and organism growth.

Contact and further information: d.waite@unsw.edu.au; andrew.rose@unsw.edu.au; garg.shikha@gmail.com

Project #4: Fouling of Submerged Hollow Fibre Membranes in Membrane Bioreactor Systems

Project Leaders: Dr Xiaomao Wang and Professor David Waite

While there is increasing use of membrane filtration in water and wastewater treatment, the efficiency of the technology is limited by the accumulation on the membrane of the solids that are being filtered (in a process known as membrane fouling). The fouling layers tend to be of highly compressible materials which decrease in permeability as the pressure applied to force liquid through the membrane increases. In this project, the ToR candidate will, in collaboration with other research staff and students, learn to operate recently developed laboratory scale membrane bioreactors (MBR) and will examine the impact of MBR operating conditions on the fouling behaviour of the solids and polymeric materials present. Experimental results will then be compared with predicted fouling behaviour based on mathematical models of hypothesized cake behaviour.

Contact and further information: d.waite@unsw.edu.au; wangxm@unsw.edu.au

Project #5: Stormwater harvesting to boost groundwater supplies

Supervisors: Dr Wendy Timms and Professor Ian Acworth

Stormwater harvesting is a possible water source for managed aquifer recharge (MAR) in the Botany sand aquifer to increase sustainable groundwater yields. New multi-disciplinary research approaches are being developed that combine urban stormwater hydrology, water treatment and groundwater hydraulics to study the fate of contaminants during recharge. The research student should be ready to apply knowledge from undergraduate studies in these areas, and to work with a team at the School’s Water Research Laboratory (WRL) at Manly Vale. The team includes world-class researchers, post-graduate students and is associated with a busy consulting business that is providing water management solutions to various clients.

This research project aims to determine the efficiency of wetland ponds and aquifer recharge to remove trace metals, nutrients and pathogens. There is an opportunity to investigate the potential impact of over 130 years of recharge using stormwater in the former Lachlan ponds area, providing a natural analogue for the design of new MAR schemes. The research is essential to underpin design of MAR schemes that ensure protection of groundwater quality and prevention of aquifer clogging. Research will involve a mix of field investigations and laboratory analysis, with the possibility to begin numerical modelling of contaminant transport processes with guidance from researchers within the WRL team.

Contact and further information: w.timms@wrl.unsw.edu.au

Project #6: Determination and Analysis of Contaminants of Concern in Water

Supervisors: Dr Heather Coleman, Dr Stuart Khan, A/Prof Richard Stuetz.

The release of persistent organic pollutants such as steroidal hormones and pharmaceuticals into the aquatic environment has recently gained much attention in Australia especially from a water recycling perspective. The long-term effects of most of these chemicals are unknown. This project will contribute to the optimization of analytical methods and an understanding of the fate and behaviour of these compounds in sewage treatment systems and the Australian environment. A combination of chemical (Gas Chromatography/Mass Spectrometry) and biological (a yeast screen bioassay) techniques will be used to give detailed data on the levels and nature of these compounds in the sewage treatment process with a view to optimization of current and advanced treatment technologies for their removal. The project with give the student experience in sample preparation techniques as well as in the use of biological and chemical techniques for the analysis of environmental samples. The student will work in the Trace Analysis group in the Centre for Water and Waste Technology under the daily supervision of Dr Heather Coleman and will be involved in liaising with water utilities and industry.

Contact and further information: h.colman@unsw.edu.au

Project #7: Buckling of continuous composite steel-concrete beams

Supervisor: Dr. Zora Vrcelj

Continuous composite steel-concrete T-beam sections, as commonly employed in bridge construction, are formed by bonding an I-section plate girder to a concrete member, i.e. reinforced concrete slab, so that the two members act as one. This bonding is typically achieved by stud shear connectors, ensuring either partial of full shear connection. Instability of the plate girder is probably the most common cause of failure of such structural configurations and despite many investigations, the mechanics of this problem has not yet been correctly or comprehensively quantified.

The work could involve some literature review as well as some simple numerical modelling by using a finite element package ABAQUS. Particular attention will be given to parameters such as the degree of shear connection, the plate girder geometry and the position of the bracing as generally employed in the negative moment regions. The research work therefore extends on the composite cross-sections topic covered in MoS and the steel buckling topic covered in Structural Engineering 3 course, and it will provide the TOR student with an opportunity to build on existing knowledge. The research student will be joining a small research team comprising undergraduate and postgraduate Thesis students and Dr. Zora Vrcelj.

Contact and further information: z.vrcelj@unsw.edu.au

Project #8: Nutrient impacts in environmental assessment of products

Supervisor: Dr Greg Peters

Nitrogen and phosphorus emissions can cause impacts on aquatic environments – these are collectively called “eutrophication”. If an engineer is deciding whether to select one technology or another, such impacts can be important, so environmental life cycle assessment (LCA) often includes an assessment of eutrophication potential. Unfortunately, approaches to doing this assessment in Australia are relatively primitive. We basically rely on a consideration of the average ratio of nutrients in organic matter. Overseas researchers have combined this with a simple transport model to produce more sophisticated potential impact assessment factors for overseas conditions.

Simple air pollution dispersion models might significantly improve Australian eutrophication equivalence factors. This project will involve a review of international approaches to eutrophication in LCA, and the development of a model to suit Australian environmental conditions. This project will suit a student with good maths and computer skills.

Contact and further information: g.peters@unsw.edu.au

Project #9: Characterisation of Hazardous Events Impacting on Sydney’s Microbiological Water Quality

Background

The greatest risks to Sydney’s water supply arise sporadically and are known as ‘Hazardous Events’. There are many types e.g. animal manure washed off the land by heavy rainfall, sewage treatment plant failures and the reduced effectiveness of natural barriers due to turbidity spikes. Despite this, the scale, frequency and duration of many hazardous event types are not well quantified. The CWWT is currently working with the Sydney Catchment Authority to characterise the impact of sewage treatment plant failure at Mittagong, Moss Vale and Lithgow in absolute terms and relative to other hazardous events with a view to better plant and catchment management.

The Project

The student would work with the Centre for Water and Waste Technology and personnel from the Sydney Catchment Authority to quantitatively characterise one or more hazardous event types such as the failure of ultraviolet treatment. The exact focus would be decided in consultation with the student at commencement of the project but could involve either desktop analysis e.g. of STP SCADA system data, or experimental work e.g. seeding of treatment units with indicator microorganisms to determine water treatment barrier effectiveness. It is anticipated that the project would provide the student with experience in professional report presentation, and acquaint them with local wastewater treatment processes, risk assessment and management and the manner in which Sydney’s water supply is protected.

Contact

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Project #10: SIGNIFICANT RAINFALL EVENTS IN SYDNEY IN A FUTURE CLIMATE: AN ANALYSIS OF EAST-COAST-LOWS

“East-coast-lows” are sustained low pressure systems that are responsible for major storms that fill the catchment areas for the Sydney water supply system. The frequency and intensity of these east-coast lows has been reducing over recent years, causing a reduction in the rainfall that feeds our water supply catchments. This reduction is speculated to be an indirect result of global warming. It is of interest whether future (higher) increases in temperature will cause this situation to be worsened or not. An increase or decrease in catchment rainfall has significant implications for the future of Sydney’s water supply.

This project will require the student to investigate the above mentioned reduction in the intensity and frequency of east-coast lows and the associated catchment rainfall for current and future climate conditions. The analysis for current conditions will be performed using reanalysis and current climate General Circulation Model (GCM) simulations, and for the future using GCM simulations assuming a CO2 emission scenario. This work requires the student to be good at computing (MATLAB) skills, and given the scope of the work, it is expected that the student would continue to work on this problem for her/his honours thesis. The project makes use of the information taught in undergraduate computing, statistics and hydrology courses (CVEN1025, CVEN2025, CVEN3526).

Interested students please contact Drs. Ashish Sharma (a.sharma@unsw.edu.au) and Raj Mehrotra (raj@civeng.unsw.edu.au). There is a good chance of a journal publication resulting from this research.

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