Water desalination to thirsty Australian's

Water desalination to thirsty Australian's



May 2007 - The delivery of energy 
efficient water desalination to drought-stricken Australia received a 
boost today with the establishment of a new collaboration between the 
government research agency CSIRO and nine Australian universities. 
The research aims to advance water desalination as an alternative water 
supply option for Australia by increasing efficiency, and reducing the 
financial and environmental costs of producing desalinated water. 
Australia, especially southern Australia, is short of water, and the 
country is experiencing the worst drought on record this year. 
Desalination of seawater is a possible additional supply, but it requires 
a lot of electricity, and is expensive, costing about A$1.10 per 1,000 
liters (US$.90 per 264 gallons). 
The new research effort, known as the Advanced Membrane Technologies for 
Water Treatment Research Cluster, is led by Professor Stephen Gray of 
Victoria University. 
As a first step, the multi-disciplinary research team will carry out an 
evaluation of existing membranes and develop new energy efficient 
membranes. 

Professor Stephen Gray is director of the Institute of Sustainability and 
Innovation at Victoria University, where he is responsible for research, 
education and industry liaison in the water, energy and sustainable 
buildings sectors. 
"Many desalination and recycling programs rely on a process called reverse 
osmosis, where the water is forced through a semi-permeable membrane, 
removing salts and any other contaminants," Gray explains. 
"These membranes need regular replacement and cleaning, but they also 
require a large amount of energy to force water through what are 
nano-sized pores," he says. 
When contaminants such as salts are removed from water, some of them 
adhere to the surface of the membrane, building up on the surface, 
increasing the pressure and energy required to desalinate the water. 
"Chemicals are used to clean the membranes, but membrane surfaces that are 
less sticky would reduce the pressure and energy required and the 
frequency of cleaning," Gray says. 
The researchers aim to improve membrane anti-fouling properties, 
increasing the ability of the membranes to clean themselves without 
chemicals. 
The research will link with and inform related CSIRO research into 
membrane and carbon nanotube water filtration technologies. 
Carbon nanotubes, molecules made of carbon atoms, are hollow and more than 
50,000 times thinner than a human hair. Billions of these tubes serve as 
the pores in a desalination membrane. 
Carbon nanotubes can be made in many different configurations. (Photo 
courtesy Softpedia)
The smooth inner walls of the nanotubes allow liquids and gases to rapidly 
flow through, while the miniscule pore size keeps out larger molecules. 
Alan Gregory, urban water research leader at CSIRO, says, "In combination 
with other research projects led by CSIRO, we aim to reduce by up to 50 
percent the amount of energy required to desalinate seawater using 
membranes. This same technology will have benefits for the treatment and 
recycling of wastewater." 
CSIRO researchers are using nanotechnology to develop a new membranes for 
desalination with electrodialysis technology, which they say may lead to 
breakthrough technologies in cost-effective and highly efficient water 
recovery systems. 
Nanotechnology for water desalination is a rapidly developing field. In 
the United States, researchers at Lawrence Livermore National Laboratory 
announced in May 2006 their creation of a membrane made of carbon 
nanotubes and silicon that may offer less expensive desalinization. 
The CSIRO scientists are developing new "inorganic-organic nanocomposite 
membranes for desalination by electrodialysis membrane process, which 
involves the incorporation of oxide nanoparticles into ion-conducting 
polymers to form new nanocomposites." 
"This also means we could potentially provide more secure water supplies 
while minimizing greenhouse gas emissions," said Gregory. 
Other partners in the membrane research program are the University of New 
South Wales, Monash University, the University of Melbourne, RMIT 
University, Curtin University of Technology, the University of Queensland, 
Deakin University, and Murdoch University. 
Funding for the research was announced by Minister for Education, Science 
and Training Julie Bishop under the Flagship Collaboration Fund. 
Desalination membrane advances cannot come soon enough for Australia, 
which is opening giant desalination plants already based on existing 
membrane technology, even if the water they produce is costly. 
The new Perth Seawater Desalination Plant, shown here under construction, 
is the largest desalination plant in the southern hemisphere. (Photo 
courtesy ABB)
In April, the Water Corporation of Western Australia opened the 45 
gigaliter Perth Seawater Desalination Plant. The US$290 million project 
will guarantee 17 percent of Western Australia's current water needs, 
regardless of rainfall or drought. 
On Tuesday Western Australia Premier Alan Carpenter announced that a 
second desalination plant of the same size would be built at Binningup. 
Meanwhile, the New South Wales Government of Premier Morris Iemma is 
moving forward with a huge desalination plant south of Sydney at Kurnell. 
The plant will use reverse osmosis technology with membranes that remove 
salts and other impurities from seawater to produce drinking water. 
The environmental assessment for the construction and operation of a 
pipeline for Sydney’s desalination plant is open for public comment to 
Monday May 28. 
As part of the desalination project, an 18 kilometer pipeline will be 
constructed from Kurnell, across Botany Bay, to Erskineville. 
Sydney Water Managing Director Kerry Schott said the Kurnell plant would 
be 100 percent powered by green energy and would guarantee Sydney's water 
supply. 
"Given the uncertainty of climate change and Sydney’s growing population, 
alternative sources of water need to be developed," said Schott. 
"The desalination plant will supply about seven percent of Sydney’s water 
supply by 2009 but it can be scaled up further if required," he said. 
"This gives us a supply of water that does not depend on rainfall." 
For more information about the Kurnell plant visit Sydney Water.  
  

       
      

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