While glass recycling rates have risen over the last decade in the UK, the amount of recycled content in glass containers has fallen, according to a report released by WRAP.

Realising the value of recovered glass - An update notes that recycled content in UK-produced glass containers has dropped from 36% in 2005 to 30% in 2007, while there was a 30% increase in recycling from 2006-7. The reason identified for this reduction is a shortage of high-quality cullet caused by the co-mingling of recovered glass during collection and processing by UK municipal councils.

The lower quality of cullets is forcing up the price of the colour-separated material. As of August 2008, clear cullet was priced at £30-35 per tonne. Between 2005-07, it was priced at £27-30 a tonne.

Exports of recycled glass cullet have therefore risen by over 40,000t in the year to June 2008, reaching 550,000t - double the amount exported in 2005 (colour specifications for green and amber bottles in mainland Europe and internationally are less stringent than in the UK). In 2010, the UK is expected to have a surplus of 40,000t of green and mixed cullet.

The Waste & Resources Action Programme has developed a best-practice guide on glass collection and processing routes, and is looking to work with materials recovery facilities to create higher-quality cullets from recycled materials. It has offered a case study on UK recycling firm Recresco as a good example of how to profit from mixed glass. The company has invested in state-of-the-art separators and processing machines to maintain high-quality cullet. More than 90% of the mixed-colour glass it processes is used in new containers.

Further information: WRAP