WRAPping up waste packaging materials

Materials World magazine
,
1 Sep 2008
The UK’s Waste Resources & Action Programme demonstrated the possibilities of lightweighting with design innovation using the ‘iconic’ Grolsh lager glass bottle

The UK’s Waste Resources & Action Programme announced on 28 July that there was a halt on levels of grocery packaging growth from 2006-7 by 32 of the UK’s major retailers and brand owners. Rupal Mehta discovers more about the materials development this involved across the retail supply chain.

Packaging has become an environmental flogging horse in recent years. It’s no wonder then that a press briefing held on 28 July to announce that 32 of the UK’s major grocery retailers and brands had achieved their 2008 target to end packaging waste growth, was well attended by national media, including The Telegraph, the Daily Mirror and the BBC.

Through the Courtauld Commitment set up in 2005, a voluntary agreement was made by supermarkets such as Tesco and Asda and brands such as Coca Cola and Mars to cut food and packaging waste by 2010. Despite a 1.85% increase in the grocery sector and a population rise of 0.5% per annum, these signatories claim to have stopped growth in packaging materials such as plastics, steel and glass from 2006-7, remaining at the 2005-6 level of 2.84Mt.

However, while the positive achievements and negative clouts surrounding packaging are brandished, the recent announcement is part of a bigger picture of materials development, testing, processing and design across the retail supply chain. This could progress to a more holistic approach to materials as new targets are set for absolute reduction in packaging and food waste by 100,000t and 150,000t, respectively, by 2010. And plans are also afoot to develop a carbon metric to measure the broader impact of packaging and its materials across their lifecycles.

Lightweighting

The Commitment was initially launched to meet the UK obligations of the EU Landfill Directive to reduce landfill waste, which is a weight-based target. Lightweighting of materials is therefore at the core of its strategy.

‘What we have done is ensure that the [lightweight packs] are acceptable to consumers, are not impacting on sales and not going to increase damage to the product. [We have also] looked at modelling the economics of [changing] technical capability,’ explains Charlotte Henderson, Retail Supply Chain Programme Manager at the UK’s Waste Resources & Action Programme (WRAP), a signatory of the Commitment.

The approach is illustrated by the GlassRite project, which looked at lightweighting glass packs across five retail sectors – wine, beer (ale and lager), spirits, soft drinks, and food. In March this year, WRAP announced that over 28,000t of carbon emissions have been cut in production and distribution by bulk importing wine and reducing the overall weight of glass wine packaging by 11,400t per year.

Faraday Packaging, a member of the UK’s Materials KTN, has been involved in the scheme, alongside trade confederation British Glass and its technical arm Glass Technology Services (GTS). Lightweight packs produced by international glass manufacturers Ardagh Glass, Quinn Glass and O-I Global were inspected by GTS, such as via heat and drop testing, as well as by packing fillers to ensure the bottles ran on existing lines.

Project Manager at WRAP, Nicola Jenkins, explains, ‘Narrow neck, press and blow [NNPB] forming technology [allows you] to push the boundaries. You can blow less glass into the mould and it has a more even distribution. Because of that, although the bottle is lighter, it is stronger. Ardagh Glass has produced possibly the world’s lightest whiskey bottle because it uses NNPB’.

Clear thinking

Jenkins notes, however, that maintaining the economic balance is complex. ‘It cannot be assumed that by lightweighting you are going to make commercial savings. It depends on how old your [manufacturing] moulds are. If you are a big brand, you will go through moulds quickly given the volumes – so if you decide to lightweight, you will have a quick turnover to make that change [economical].’

For low-volume products, there might be a long life left in the mould and it could cost the glass manufacturer £30-40,000 to change it.

The benefit for manufacturers, however, is that glass is energy intensive to form. ‘So lighter containers allows them to get more product from a tonne of glass,’ says Jenkins.

Having demonstrated that lightweighting is technically feasible and acceptable to consumers, the GlassRite project will now explore production of a sub-300g wine bottle, as well as reducing the weight of champagne and sparkling wine bottles. Jenkins says, ‘It is challenging because the sub-300g bottle is produced in France and South Africa, but take-up is not there due to market perception [of it being] ugly. We want to produce a bottle that is technically feasible and looks good. [Also,] can a champagne bottle that is lighter withstand the pressure in that product?’

Full circle

As signatories of the Courtauld Commitment forge ahead, WRAP attempts to further close the loop. It is working with UK local authorities to overcome their varied recycling schemes and develop best practice, has demonstrated the feasibility of mixed plastics recycling and hopes to increase the level of recycled content in packaging to stimulate market demand. It is also bringing retailers and local authorities together to identify ways to increase the uptake of recycling and decrease confusion among consumers about materials by mono-material packs and clearer labelling.

Paul Butler, member of IOP: The Packaging Society’s Board, comments, ‘Future metrics will need to look at overall resource-efficiency and the trade-offs between packaging and food waste. [Manufacturers cannot help] by being part of “materials wars” of “I’m more sustainable than you!” Metals could have improved formability to enable more complex shaping, aluminium could have greater use of scrap and continuous casting of sheet, and plastics could have better barrier properties and more easy-to-recycle laminates’.

Further information:

WRAP