By David Bruce
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Professor Barry Hart believes the need to find more efficient ways of treating wastewater is becoming increasingly urgent. |
While the days of untreated sewage being left to disperse in the gutters of city streets have long gone in most societies, the world's rivers and oceans have become the prime dumping ground for human waste that has undergone various degrees of treatment.
And according to Professor Barry Hart, director of the Water Studies Centre in Monash University's Faculty of Science, the need to find more efficient ways of treating wastewater is becoming increasingly urgent.
"As the demand increases for cleaner waterways, cleaner beaches and cleaner food production, so too does the need to find better ways of treating wastewater that flows into the rivers irrigating our farmlands and into the oceans sustaining our marine life," he said.
Pioneering work by a team of scientists led by Professor Hart has lifted the monitoring of water quality and wastewater processing to a new standard of precision and efficiency.
Flow injection analysis (FIA) technology is in relatively common usage in many industries around the world. When coupled with sophisticated instrumentation such as modular analysers, it enables scientists to quickly iden-tify the chemical components of any liquid.
Now, for the first time, Monash scientists have successfully adapted FIA techniques to the treatment of wastewater.
Using the technique, researchers and water management agencies can rapidly - and with greater detail - pinpoint nutrients which might be causing problems, firstly in our sewerage treatment plants but ultimately in our public waterways. The FIA process is being tested at two water treatment plants at Sydney Water's Warwick Farm.
Conventional monitoring at wastewater treatment plants involves manually taking samples from the treatment ponds and analysing them in a laboratory for nutrients such as phosphate, nitrate and ammonia. The turnaround time for test results is half a day at best, which means that problems are usually well established by the time they are discovered and so require greater effort to resolve.
And according to Professor Hart, this can sometimes be an ineffective way of controlling and regulating the quality of wastewater.
"The small amount of information that can be gained in this way is limiting our overall understanding of the microbial processes that are occurring in the treatment plant," he said.
"Basically, what we have now all over the world is an extremely rudimentary way of monitoring how successful or otherwise we are in treating the effluent that we discharge into our rivers and oceans. If you compare this to other industries like the petro-chemical industry, the wastewater industry has very old and slow methods of monitoring its ongoing effects on the environment."
In a pilot plant at Sydney Water's Warwick Farm Technical Development Unit stands a modular analyser the size of a refrigerator which is responsible for vastly improving the quest for cleaner effluent. The Automated Flow Injection Monitoring System continually monitors water samples, producing an analysis within 10 minutes. In an adjacent control room, plant operators use a sophisticated software program developed by the Monash scientists, which produces a simple diagnosis of the current situation.
Back at Monash in Melbourne, Water Studies Centre researchers Dr Ian McKelvie and Dr Graeme Cross run a supervisory eye over data which is simultaneously downloaded onto an Internet site from the Sydney control room. At any given time, both the Monash researchers and the wastewater plant operators at Sydney Water can tell whether the plant is operating effectively, allowing treatment to be quickly adjusted accordingly.
As well as channelling cleaner wastewater into the environment more effectively, the FIA approach has obvious advantages for the plant operator in terms of greater efficiency and therefore lower operating costs. As population pressure increases - and levels of wastewater rise - such issues will be of increasing importance.
The potential for the FIA technology in other parts of Australia and in Asia, Europe and North America, in particular, is enormous.
The FIA project has been funded by a $1 million grant from the Industry Research and Development Board of the Department of Industry, Science and Tourism. It is a colla-borative project between Monash, the University of Queensland, Sydney Water and the NSW Department of Land and Water Conservation.
The Water Studies Centre, as a partner in the Cooperative Research Centre for Freshwater Ecology, has for more than 20 years led research into the health of Australia's waterways. It is also involved in several major international projects including a bio-assessment program with the Indonesian Government on the East Java River.
Professor Hart is also advising on a major project to preserve the river ecosystems downstream of the Lesotho Highlands Water Development, a large Snowy Mountains-type development in southern Africa.
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Mr Jeff Bailey of Sydney Water with the modular analyser at the Warwick Farm wastewater treatment plant. |
Dr Ian McKelvie and Dr Graeme Cross monitor the data out of the Sydney Water wastewater plant from their offices at Monash in Melbourne. |
'The World of Science' is a free public lecture series presented monthly by Monash's Faculty of Science. For further information, contact Dr Leo Brewin on (03) 9905 4456 or email leo.brewin@sci.monash.edu.au
