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The technology, involving the use of microwave processing, will change forever the way that wood is processed, according to Peter Vinden, of Melbourne University's Forestry Department. It will open up new products for both the softwood and hardwood plantation sector, and transform the economics of the existing native hardwood timber industry. This, in turn, is likely to create more employment and economic growth in rural and regional areas, and generate new exports.
"The new technology has the potential to not only reduce the drying time of timber from months to a matter of days, but also to change the structure of timber to improve its strength, stability and durability," said Professor Vinden, who is the CRC's chief executive. The research, which has been conducted for the past five years at the university campus at Creswick, near Ballarat, will be greatly expanded and developed by the new Cooperative Research Centre for Innovative Wood Manufacturing.
The research centre, which will have its administrative headquarters in Melbourne, will bring together researchers from Melbourne University, Swinburne University, the Queensland Forest Research Institute, the Western Australia Forest Products Commission, the CSIRO Division of Building, Construction and Engineering, Furntech Tasmania, private companies and furnishing industry associations.
A substantial proportion of Australia's forest research capabilities will be contained in the CRC. Funding for the CRC will total $60million over seven years, and includes $16.3 million from the Federal Government and substantial backing from different sectors of the timber industry. "The CRC is an absolute godsend," Professor Vinden said. "It will give us the resources to make the project work." The microwave processing physically modifies the wood's structure. The microwave facility in the Creswick laboratory has a capacity of 60 kilowatts, 100 times more powerful than a domestic microwave oven.
Professor Vinden said it normally took about one year to process a hardwood log, but microwave processing had cut this to just four days. Potentially, hardwood logs could be processed in nine hours. "Radiata pine, because of its lower moisture content, can be processed in two or three minutes," he said. The microwave processing is not the same as kiln drying; the wood is modified so that after the microwave processing it can dry 10 times faster.
The timber is sent through the oven on a conveyor belt. "The intense application of the microwaves creates a new pathway for moisture movement in the wood," Professor Vinden said. The cross-section of the wood is expanded by 12-13 per cent, making it 2000-fold more permeable. The wood becomes "spongy" and can be compressed by hand. Wood resins are applied to the conveyor belt and the wood is compressed back to its original dimensions.
"The process is suitable for all wood species," Professor Vinden said. "You get the same modifications in all woods." English Oak was the first species tested, and 15 eucalypts have also been put through the process. There are also other benefits. "The strength can be doubled and control over other properties modified, increasing the binding strength, hardness, dimensional stability and durability," Professor Vinden said.
"A green log can be batch-processed and emerge suitable for flooring or panel quality." Professor Vinden said the technology had been proven in batch processing. "Now we need to create and develop new product lines and models, and optimise the process and what is theoretically possible," he said. "We also have to make sure it is economically viable." Three worldwide patents have already been taken out on the technology, including generic covering of the concept, which Professor Vinden said had never been applied before.
A driving force behind the new technology has been a Russian scientist, Professor Grigori Torgovnikov, who was the head of a Moscow microwave processing research institute in the former Soviet Union. Professor Torgovnikov has been at Creswick for about five years. The technology has been dubbed with the acronym "Vintorg" after the names of the two men.
Professor Vinden said the CRC also aimed to develop other new products based on the use of new resins that interacted quickly to create good binding. "Current resins have disadvantages; some are toxic, so we are aiming for non-toxic resins and control over the rate of cure," he said.
Commercialised microwave processors are unlikely to be too expensive for timber mills to buy. Professor Vinden said detailed costings so far had been very positive. For example, using microwaves to produce a panel product amounted to half the conventional cost. The shorter time required for kiln drying would also dramatically lower energy costs.
The upshot was that timber production could become cheaper for existing players, but the way would also open for new companies to establish themselves in the industry, he said. Apart from the radical improvement in processing, the new technology also promises to create a new range of value-added products, and "reclaim" products overtaken by other materials - for example, windows, which had been lost to steel, aluminium and plastic.
Professor Vinden said CSIRO's division of building and construction had developed technology that activated the surface of the wood so that it was more compatible with resin, glue and paint. "This will increase the binding strength and durability of the product. The disadvantage of wood in the past is that it split and lacked durability," he said.
"The combination of microwave and surface activation technology will create a high performance material that will have the aesthetic appeal of wood, and the economic and technical advantage of a new material." Other possible products included the turning of wood waste, not into woodchips, but into non-toxic wood resin through a heating process. "The end product would have cellulose as a residue, which could be the basis of another industry based on cellulose - but that's another story," he said. Another process, steam-binding wood, could potentially be combined with microwaves to possibly mould wood into different shapes, but that has not been tried yet.
Professor Vinden said that, if there were a 100 per cent pick-up of the technology, the rough estimate was that it would add $6 billion a year in value to the timber industry in Australia. "You can used your imagination what it would be worth on the world market," he said. Microwave technology opens up dramatic new possibilities for the plantation sector. Blue gums, such as those in western and south-west Victoria, are currently being planted mainly to be harvested in 10 years for pulp, but new products could be created from blue-gum logs.
Normally, blue gums take 20-25 years to grow to a suitable quality for saw logs. However, Professor Vinden said that, with genetic selection, blue gums could produce the properties and diameters needed for sawlogs at an earlier age. "I see a major opportunity for the blue-gum business," he said. It is a similar scenario for softwood plantations, with microwave processing overcoming many of pine's disadvantages. Professor Vinden said the core wood had poor qualities compared to mature wood. "You can overcome the problems of movement and stability, durability, strength and hardness through microwave processing," he said. "You can reposition core wood from a low-value wood to a high-value furniture product." It would also be possible to colour the wood and effectively duplicate tropical hardwood, making the new, processed, plantation-wood ebony in appearance.
Professor Vinden said the increased role for plantations did not mean the native hardwood industry did not have a future.
Australia's native forests, with the regional forest agreement process, were scientifically managed and grown on a sustainable basis.
Professor Vinden said the RFA process had been effective, protecting virgin bush that should never be touched and ensuring biodiversity, water quality and the preservation of wildlife.
At the same time, the RFAs had given industry security of resource, although it had been hard for industry, with some mills closing down. "Australia still has much native forest, and with careful selection you can use native wood for furniture that will last forever if the furniture is of good quality," he said. "Australia has some of the most outstanding timbers in the world. It would be almost scandalous not to use them."
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