Microwave-based technique recycles medium density fibre (MDF)

Materials World magazine
1 Nov 2007

Nviro Cleantech Ltd, based in London, UK, plans to start commercial trials next year for a microwave-based technique to recycle medium density fibre (MDF). No viable commercial system for recovering and recycling these wood fibres into a reusable form currently exists.

Made from scrap wood, sawdust and adhesive binding agents such as urea formaldehyde, MDF was developed as an alternative to raw timber.

According to figures from the UK’s Waste Resources and Action Programme (WRAP), about 95% of the 30 million cubic metres of MDF produced globally per annum end up in landfill. And up to 18% of the material is lost as scrap early in its lifecycle during conversion into goods such as furniture. Landfill costs stand at £35-70/t, and the adhesives used in the material release methane on degradation.

Chris Every, Chief Executive of Nviro Cleantech, says, ‘Decisions are being made and legislation proposed at the European and member states level, and in the United States, to get this material out of landfill. The time has come to look at ways of reusing the fibre.’

Microrelease is a patented technique developed by the UK’s Furniture Industry Research Association and scientists at the University of Wales, Bangor, which involves processing scrap MDF into its building blocks. Using an industrial scale microwave, the tightly packed fibres are mechanically loosened and burst open by water molecules to create a fibrous mat that is pressed and dried for reuse.‘It leaves the fibres in good condition – untouched by mechanical means,’ explains Every. Nviro Cleantech is commercialising the technology.

The process can be optimised pre- and post-treatment to cater for waste from manufacturers, converters who produce finished goods, and from construction, where scrap often contains nails and screws. But Every is tight lipped about the specifics.

Potentially saving the industry 10-12% in turnover in landfill costs, he argues that the technology should not be expensive to operate. For large manufacturers, Nviro Cleantech can install and operate the equipment on site, taking away the processed material for reuse. Alternatively, SMEs can employ the company to collect waste MDF, requiring no further action.

As well as initiating commercial trials next year, Nviro Cleantech, as part of a WRAP-funded project, will be investigating alternative end uses for recycled MDF fibre, such as in plastic-wood composites. Members of the initiative will compare the performance of these materials against those made from virgin wood, as well as explore the economic and environmental impact of using recycled MDF.


Further information:

Nviro Cleantech