Photoillustration: Raymond Nilsson, SINTEF Media

Recycling or degradation?

We consciously wash plastic containers and take out the bags for recycling. But is this beneficial? Can the option of an additive that breaks down the plastic be just as good?

Two research teams are working side by side at SINTEF on totally different solutions about what we should do with our plastic waste. While one team is trying to come up with the best possible recycling processes for the used plastic, the other is working to make the plastic disappear without any form of recycling.

LONG LIFE – SHORT PROCESS

”If handled correctly, polymers can have a long life,” says senior adviser Line Telje Høydal, who represents one of the research teams. She is working with material recycling and believes this is a socially correct way to take care of the materials. “The materials are slightly reduced each time round, but recycling each item five or six times is possible,” she says, adding: “The greater the amount of material recycling, the better the accounts will be.”

Senior research scientist Fredrik Männle represents the other team. He came in contact with a company in Sunnmøre a few years ago while working on general additives. They have collaborated on the development of a method degrading plastics, which is sold and marketed by the firm Nor-X Industry AS. By adding the substance Nor-X degradable in the plastic materials during production, the materials will then decompose in a short time when exposed to sun, air and humidity. As an additive in a plastic carrier bag, it will break down quicker than a fallen apple. After two weeks in the sunlight, the bags will still have 90 percent of their strength, but after five weeks only traces will remain.

ENVIRONMENTAL ADVANTAGE

Line Telje Høydal says that Norwegian industry quickly realised that recycling industrial plastic waste was of economical benefit, but the plastic fraction of municipal solid waste has so far not been marketable.

“It has, therefore, been an important task for SINTEF to improve the recycling process to achieve a better quality and find the optimal use for the plastic materials that are collected,” she says.

“We now have many studies and data on recycling. Unless you use a lot of energy on the recycling process, it will often be environmentally better to recycle than utilise another form of processing the waste.”

The researchers have assisted companies with sorting and identifying different types of plastic. They have also carried out quality controls, mechanical testing and aging tests. One of the companies SINTEF has assisted is Folldal Produksjon, which incorporates recycled plastic in the manufacture of its hawser. These hawsers are used in the North Sea and so we can say that the process has gone full circle.

FACTS

  • Annual consumption of plastic packaging in Norway is 130,000 tonnes, and the amount is increasing on an annual basis by four percent.
  •  24% is recycled as materials or chemicals, 57% is incinerated and 19% ends up in landfills or in the countryside.
  • In 1996, Norwegian authorities established Plastretur AS, (now called Emballasjeretur) to handle recycling and try to achieve the authorities’ requirements of 30% material recycling by 2008.
  •  The EU Landfill Directive targets to reduce land-filling of degradable or recyclable waste from 2009. Norway will follow this and has introduced similar targets from 2009.

 

NICHES

But what about all the plastics littering the countryside? Wouldn’t it be great if this could just disappear? Can inbuilt decomposition simply be the answer to the world’s significant littering problem?

Germans, French and, in particular, Hungarians are interested in the Norwegian additive product. Hungarian authorities have endorsed the additive in some plastic products to control the country’s plastic problem. German farmers are testing out degradable agricultural films in vegetable production. Mulch films are difficult to collect and recycle once used. A much simpler solution is that the plastics decompose after four to eight weeks.

Nor-X would also like the additive to be used in the packaging of fast foods and other consumer items. Everyone knows how ugly it is when the snow disappears in spring and large quantities of sodden rubbish are visible.

A SOFT OPTION?

The conflict between the two solutions is if the additive is used in ordinary plastic carrier bags and these are later recycled, then products made from these recycled plastics can degrade after a given time.

”I believe the degradation solution is the wrong way to solve the littering problem,” says Høydal. ”After all, we have a political resolution in Norway to recycle plastic. Introducing additives will damage the established recycling process.”

However, Nor-X is trying to produce evidence to show that the additive won’t damage the recycling of plastic products. ”Trials show that this type of plastic can probably also be recycled. The answer is to add a substance that neutralises and stops the degradation,” says Männle.

Nor-X’s aim now is to provide evidence that the two solutions (recycling and degradation) complement each other and collectively provide the best solution for protecting the environment.

PROFITABLE?

In order to be able to utilise the plastic, it is necessary to have a saleable product. For many years industry has been recycling plastic – basically because it is economically profitable. Nor-X also believes its product will be profitable in the future.

What will be socially profitable?

“There are many types of accounts,” says researcher Hanne Lerche Raadal from the Stiftelsen Østfoldforskning. “We basically do environmental calculations on different recycling and treatment systems. We look, for example, at CO2 emissions and the pollution of water and NOX by waste disposal plants. Such accounting processes clearly show that it is environmentally profitable to recycle.”

For its part, Nor-X has had meetings with the State-run recycling company, Emballasjeretur, to start a joint project to determine what happens when plastic containing the additive is recycled. The company believes that there will be sufficient plastic in the world to accommodate both recycling and decomposition.

In the end, it is the ultimate solution for the environment that must count.

By Jan Helstad/Åse Dragland