New opportunities for recycling

The commissioning of an additional glass furnace in Auckland has created new opportunities for local authorities when it comes to their recycling efforts, says waste expert Sheryl Stivens.

Ashburton is well down the track in producing clean, sorted glass to be re-melted and re-used. That wasn’t the case in many parts of New Zealand, however, particularly areas where wheelie bins were used, she said.

“Putting glass in wheelie bins is the worst thing for recycling. You end up with highly contaminated products all the way through the rubbish.”

For glass to be accepted by the Auckland glass smelter, it needed to be free from contamination and had to be sorted by colour. And Ashburton’s rubbish bag and recycling bin method of kerbside collection gave the district the best shot at ensuring most of its unwanted glass could be re-melted, she said.

“The ultimate solution for glass in New Zealand is bottle to bottle recycling. It’s preferable to crushing or other solutions that are about down-cycling.”

Some local authorities crushed glass to use in foundations or on roads and while that was re-use, it was not ideal, particularly in an area such as Ashburton where aggregate was plentiful, Mrs Stivens said.

“This investment in the new furnace in Auckland is great, but it now means they can’t get enough quality glass. That means we need to convince all councils to use bags and recycling bins, to keep it separate and to keep it clean.”

Glass that arrived at a recycling centre mixed with other rubbish had to be hand sorted and this was too labour intensive to make the recycling exercise economic in many cases, she said.

“In Ashburton people are doing very well. I think we’re ahead of the field. We just have to keep reminding people to put their glass in their recycling bins or to sort it at the depot.”

In spite of the recycling industry’s best efforts, there were still some glass products that were not able to be recycled – light bulbs, crockery, pyrex and lead crystal. 

“Window glass is also a problem but that is now recycled into pink bats, but at present there is enough glass in Christchurch to provide all they need so right now we don’t have a market for this.”

Progress in finding solutions to recycling problems was sometimes slow, success often came in bite-sized chunks, but it was an industry that had to grow, Mrs Stivens said.