11 Oct 2018

Composter changes Raglan's recycling

1:38 pm on 11 October 2018

by Ellie Jay

Raglan’s Xtreme Zero Waste community enterprise is discovering compostable items placed in its industrial scale composter aren't always as compostable as they may claim to be.

A lack of national standards around product packaging means consumers are being duped into buying things which aren't nearly as green as they seem, say waste management companies.

Lack of clarity over terms like "biodegradable" and "compostable" and the number of different symbols on products has meant that without the infrastructure in place to sort or process these products, a lot is ending up in landfill.

Xtreme Zero Waste (XZW), in collaboration with the community led Plastic Free Raglan (PFR) project, is trying to tackle this problem and has started a trial of compostable products in its commercial composter.

Everything the town and surrounding rural area 10,000 inhabitants throw away is taken here to Xtreme Zero Waste’s Resource Recovery Centre. At the moment Xtreme Zero Waste diverts 75 % of waste from landfill and estimate their new residential food-waste collection service, helps them divert another 19 percent through the composter.

Raglan’s foodwaste is processed through a Horizontal Composting Unit. The composting unit is a concrete trough 30 metres long and 4 metres high with a sliding roof. When it rolls back you can see piles of food and garden waste in various stages of composting. Each pile is a different week's worth of the town's waste.

On the back of the successful Plastic Bag Free Raglan project the community has turned its focus onto other single use packaging and has developed the Plastic Free Raglan PFR community collaboration involving Xtreme Zero Waste, Raglan Chamber of Commerce, Whaingaroa Environment Centre and Para Kore.

"We've become plastic addicts," the company's organics team leader Liz Stanway said.

"With China saying they don't want to process the world's plastic packaging, we really need to look at how we design and consume single-use packaging."

There is a global shift away from single use plastic packaging to single use compostable packaging. Amanda Moxey is a researcher working with XZW and PFR looking at single-use compostable alternatives to traditional plastics. The trials involve adding takeaway compostable food packaging, certified to several international composting standards, through the XZW composter to see if they do break down, as advertised. The initial results have been promising. After the 12-week process the final compost product looks just like freshly dug earth, with no signs of the packaging or the food waste.

New Zealand does not have a certification process of its own. But Ms Moxey said this was not a problem; international standards were stringent enough.

However, labelling products did need to become clearer, she said.

"We need to adopt some form of labelling like we have for recycling that would have a very clear logo," Ms Moxey said.

Most products that claim to be compostable are often only compostable in industrial facilities, she said.

Without adequate collection and processing facilities in New Zealand most compostable items most likely end up in Landfill.

Composting units such as the one at XZW could be scaled up to service other communities.

Despite this, Ms Stanway warned against thinking certified compostable single-use items/packaging as a silver bullet.

"I look in the supermarket shelves and think, 'If all of that was compostable what would the impact be?' The impact would be the mountains of plastic we see on TV not being able to go to China would suddenly become a compostable challenge."


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