'Turning blue rubbish into blue gold'

Connections Centre manager Brian Murray with an Otago Polytechnic-built shredding machine that...
Connections Centre manager Brian Murray with an Otago Polytechnic-built shredding machine that can turn plastic milk bottle lids into recyclable material. PHOTO: GREGOR RICHARDSON
The humble plastic milk bottle lid has long been a common sight at Dunedin’s landfill.

But now it is being seen as "blue gold" by the Connections Centre in Corstorphine, after it was given a shredding machine that can turn them to fine plastic particles which can be melted and recycled into other plastic products.

The milk bottle top shredder was designed and built by Otago Polytechnic engineering students, with the Connections Centre in mind.

Connections provides training and employment opportunities in Dunedin for people with high-support needs.

Otago Polytechnic allied trades programmes head David Bettis said safety considerations in the project were extensive.

"The shredder has been carefully designed to incorporate extra safety features.

"We had about a dozen New Zealand certificate in electrical engineering (level 3) learners designing electrical control circuits, and considering things like emergency stops and guard switches, as well as doing a risk assessment."

He said the project also included input from mechanical engineering (welding and fabrication) students as well as occupational therapy students, who worked with Connections to help identify and develop goals based on those with high needs.

Centre facilitator Benton Glassey said the shredder would be operated by someone in the wider community with a disability who would be helped to use it safely.

"The outcomes are not just about recycling.

"The project has got a great community grassroots kind of vibe to it. This includes social connotations around collecting bottle tops, which in turn raises awareness around disability.

"There’s a lot of energy and life to all this.

"It’s a great example of how student-led innovation intersects with community collaboration — to the benefit of many."

Because of processing difficulties, milk bottle tops have not been easily recyclable in the past.

However, the new machine would mean they were no longer destined for landfill. He said once the bottle tops were shredded, they could be sold in bulk as mouldable thermoplastic, which can be melted and remade into a range of products.

Centre manager Brian Murray was delighted the shredder was now installed, and the organisation was looking forward to doing its bit for plastic recycling.

"It’s turning blue rubbish into blue gold."