29 September 2009:
Millions of tonnes of unwanted waste spewed out by
Australia’s power stations, mineral processing plants and
municipalities can be re-used to create fertility, health, wealth,
beauty and abundance.
Professor Richard Haynes of CRC CARE and the University of
Queensland will tell the CleanUp 09 conference in Adelaide today of
striking progress in developing new uses for substances which have
become a real headache for society to dispose of.
“A major thrust of our work is to transform industrial and
municipal wastes that nobody wants into an environmentally friendly
opportunity to make viable and marketable products,” he
says.
“For example Australia currently produces 13 million tonnes
of flyash from coal-fired power generation and a similar quantity
of ‘red mud’ from bauxite processing, along with
millions of tonnes of biosolids from urban sewage treatment and
green waste from parks, people’s gardens, food and factory
effluent.
“By combining these resources in creative ways we can produce
new products to boost fertility, overcome soil deficiencies, absorb
toxic contaminants and beautify our urban landscapes,” Prof.
Haynes explains. “These include garden mulches, organic soil
amendments, garden compost, potting media and specially
manufactured soils.”
Research at CRC CARE has included co-composting green waste with
inorganic substances such as coal fly ash and organic resources
such as grease trap waste, poultry manure and biosolids.
“Because urban green waste usually contains a lot of shredded
wood and bark it doesn’t break down all that easily.
However by adding readily decomposable material, this raises the
temperature and produces a much better compost.
“By adding 20 per cent fly ash to green waste we can greatly
increase its water-holding capacity, producing a topsoil
replacement that is highly suitable for use in urban settings where
people want to save water.”
Prof. Haynes team have also investigated a wide range of inorganic
wastes such as steel slag, blast furnace slag, coal fly and bottom
ash, red mud, water treatment sludge as well as organic sources
such as tree bark, sugar mill mud, spent brewery yeast and prawn
processing waste
“We have shown some of the more promising materials can be
used to immobilize heavy metals in a metal-contaminated soil. This
means we can use industrial wastes to prevent the toxic
contamination caused by other forms of waste disposal.
“Both sugarcane and rice have a high requirement for silicon
in the soil to grow properly – and we have found that slags,
red mud, fly ash can all provide this important nutrient to crops
at low cost.
“Likewise wastewater from dairy and meat processing plants
can be used to supply nitrogen and phosphorus to farming soils if
applied in the correct amounts.
By such methods, Prof. Haynes says, some of society’s worst
waste problems can be turned into assets, helping to provide food,
fertility and healthier landscapes while saving water and
preventing pollution.
Professor Haynes will deliver his paper at 10.40 AM on Tuesday
September 29, 2009.
The CleanUp 09 conference is being held at the Hilton Hotel,
Adelaide from September 28-30.
More information:
Professor Dick Haynes, CRC CARE and UQ, 0448 501 352
Peter Martin, CRC CARE communication, ph 08 8302 3933 or 0429 779
228
Peter.martin@crccare.com
Conference number: 08 8217 2000 and ask for CleanUp 09
