40,000 tonnes of Auckland's plastic waste to be turned into concrete from end of 2019

A Kiwi company will begin turning tens of thousands of tonnes of Auckland's plastic waste into concrete as soon as next year.

The issue of what to do about plastic waste has dominated headlines around the world in the past year in particular. Supermarkets here and overseas have banned single-use plastic bags, started plastic-free aisles and scientists have discovered plastic waste has reached all parts of the world, including the deepest part of the world's oceans.

Enviroplaz's founding director Peter Barrow told the Herald it had been a dream of his for the past 20 years to turn plastic waste into something useful rather than dumping it at the landfill.

And finally, he says, that dream is soon to happen.

There isn't much to show by way of the plastic-to-concrete process at their Wiri-based office yet, with just a large shelf display with samples of each stage to look at.

At the top there is all kinds of plastic - milk and soft drink bottles, used oil containers, plastic bags and used biscuit packets. Beneath that, there's the shredded down version of the waste above and then a further shredded down box of tiny chips that have had chemicals added, and finally, the end product, little rocks they've called Plazrok.

Barrow says it doesn't matter if the waste they collect is clean or where it's come from, as it can just the same be transformed into a high quality aggregate for concrete.

Earlier this month, Barrow says some of the country's biggest plastic producers, such as Griffins, Eta, Bluebird and Fonterra were invited to watch their own plastic packaging being put through its small prototype and turned into Plazrok.

"All of them have the same problem - What do we do with it? Where does it go? How do we get rid of it?"

He says the companies have come to see themselves as responsible for looking after the problems they're creating, which is great in his opinion but should have happened sooner.

Enviroplaz chief executive Alister Lawrence says demand for Plazrok is also booming overseas.

"We've had the government in Singapore want to get engaged with us. We've got big businesses in Thailand, Indonesia, the United States."

Lawrence says they hope to have its first Auckland-based plant, with imported machinery they've tried and tested in the United States, by the end of next year.

"We then think when we have that plant up and running we'll have something to show the rest of the world."

And later down the track, Lawrence envisions they will also start mining landfills for plastic and turning that into concrete.