KEY POINTS:
An idea that began with a toasted sandwich maker in a Kiwi kitchen could provide the answer to one of the world's biggest environmental problems.
A New Zealand trio, including former All Black Byron Kelleher, have come up with a way to effectively dispose of millions of plastic
shopping bags that clutter landfills around the world.
Using the process of Thermofusion - which Kelleher, Matthew Darby and Hamish McCrostie have patented as a "world-first" - the plastic bags are melted down and moulded into items such as plastic shipping pallets.
"The plastic waste goes into one end and a plastic pallet comes out the other end," Mr Darby said.
"It's a world first insofar as it is a machine that can take plastic waste from virtually any waste stream and reprocess it."
Linda Norris, the chief executive of the Sustainable Initiatives Fund Trust, which encourages recycling innovation, called the trio's development a great breakthrough.
"I'm happy to see a notorious waste item turned into a wanted, valued resource and creating a viable business in Christchurch that provides jobs."
Each year between 500 billion and a trillion plastic bags are used worldwide, but only about 1 per cent are recycled because there has been no commercially viable and environmentally friendly way to recycle them.
Although plastic recycling plants are operating around the world, the vast bulk of waste plastic does not get recycled because it is either of mixed grade or contaminated. "What we wanted to do is develop a technology for plastic that wasn't already being recycled," Mr Darby said.
He came up with the Thermofusion concept after several nights of experimenting in his kitchen.
"I had a pile of plastic bags and I started playing around with melting them. I tried various kitchen appliances and then I hit upon the toasted sandwich maker because I could control the heat.
"Cooling the plastic down was problematic because, of course, I couldn't run the toasted sandwich maker under water, so I decided to put it in the freezer.
"That's how we initially came up with the process. Then we just had to work out how we could do it in a more controlled way."
Mr Darby and his partners spent three years designing a prototype machine. After testing, a commercial production machine was built that could operate around the clock.
"And it's not just plastic bags that it can chomp up and spit out into plastic pallets," he said.
"The machine can handle all types of plastics."
The trio's Christchurch company, Range Industries, is in discussion with five overseas firms wanting to buy its machines.
Interest is coming from Europe, South Africa and the United States.