26 July 2011

Glass sector faces mix of cullet challenges

The UKs glass recycling industry is at a crossroads in terms of future direction as more local authorities opt to collect packaging glass mixed and process it through materials recycling facilities or send it for aggregates.

As a consequence, the glass industry is again airing concerns about the amount of material it will receive if more tonnage goes for aggregates use. At the same time, it is arguing that glass cullet has to be supplied at an affordable price, while recognising the additional costs incurred in colour sorting MRF glass material.

Bottlemaking at O-I: the company has expressed concerns about the economics of making glass from cullet compared to virgin materials

Bottlemaking at O-I: the company has expressed concerns about the economics of making glass from cullet compared to virgin materials

The situation is complicated by uncertainties in the packaging waste recovery note (PRN) system which has seen glass PRN prices fall, offering less support to cover sorting costs.

There is something of a consensus within the glassmaking industry that prices the sector has to pay for cullet are higher than necessary, partly because the PRN system has forced prices for cullet up although critics would say that the glassmakers always want recycled cullet at a cheap price.


The pricing situation can be critical in terms of whether glassmakers opt for using raw materials against the challenge for them of promoting the environmental benefits of recycling as well as the need to generate packaging recycling evidence in the form of PRNs.

In 2010 about 1.4 tonnes of glass packaging was collected with 595,000 tonnes used for remelt into new bottles and jars, about 850,000 tonnes was used for aggregates, 100,000 tonnes for glass fibre and 262,000 tonnes exported.

Representations have been made to the Advisory Committee on Packaging on costs. Last year the committee was told by glassmaker O-I of the challenges of getting cullet of sufficient quality for it to recycle and the economics of making glass from recycled material as opposed to virgin.

The glass sector has told letsrecycle.com that a whole range of issues are coming to the surface at present including:

– The acceptability of glass from MRFs
– The cost of using colour sorted material to make new glass
– Quality issues for glass in aggregates
– The low value of PRNs
– The potential for more bottle banks

There is an acceptance among recyclers that mixed cullet is here to stay because of the removal of bottle banks alongside the growth of commingled collections and MRF sorting. But, the question is being asked as to where the material will go, with three main options: to the UK glassmaking industry; exported for glassmaking (mainly in southern Europe); or sent for use in aggregates in the UK.

Small size

UK glassmakers have reported problems with using some MRF cullet, largely because of its small size, as well as having some contamination. One source told letsrecycle.com: This glass could potentially be used for green glassmaking but the UK has generally stricter quality standards than might be found in southern Europe and prefers pieces of glass 10mm plus. So, some of the smaller and more contaminated material may be exported as the overseas glassworks may be content with higher reject levels.

The main route for MRF glass has been to aggregates users. However, there have been restrictions on the input of the glass, partly because of contamination from organics and partly because of the lower price of PRNs. Consequently, gate fees for the material are thought to have risen causing concerns among some MRF operators.

Bottle banks were first installed in Barnsley in 1977, pictured are the 25th anniversary celebrations with Glass Recycling UK, organised by letsrecycle.com in 2002

Bottle banks were first installed in Barnsley in 1977, pictured are the 25th anniversary celebrations with Glass Recycling UK, organised by letsrecycle.com in 2002

Cleaning up of the glass from MRFs for use by the glassmakersisbeing carried and some in the sector consider that this is the way forward and high levels of quality can be achieved, although the size of the material sent to the sorting plant remains important.

Tim Gent, director of glass recycler Recresco, said that the company was able to produce a material of high enough quality using optical sorting for MRF glass. And, he confirmed that the value of the PRN was important to the sorting sector because of the costs incurred in the process.


Viridors new glass processing plant in Sheffield has also been highlighted as a significant development in the sector as it produces glass for the glassmakers from mixed material, some of which is from MRFs.

The company also has facilities at St Helens and at Bonnyrigg in Scotland but Sheffield is the most advanced with the location chosen to process feed material from various sites in the UK at reasonable transport cost. It is thought that the company is aware of the cost issues in terms of material it supplies to the glassmakers and is aiming to build long-term supply relationships.

Viridor chose German company Mogensen as its technology supplier and partner for the Salmon Pastures plant which has a maximum capacity of 150,000tpa. The latter said: For the Sheffield project it was Mogensens superior ability for screening, crushing, metal removal and colour sorting equipment plus their unique ability to meet Viridors high quality specification for the final cullet that led to their selection.

Other companies in the sector are facing the challenge of having to maintain investment in sorting to meet the demand and competition that is developing for sorting cullet. They are grappling with the end price they will receive for material alongside the investment costs needed.

And, in the future the economics of glass recycling could be complicated by decisions made at European level over when glass is not a waste. A policy on this is being developed by the European Unions Joint Research Centre (see letsrecycle.com story) and could go to the European Commissions Technical Adaptations Committee this month or after the summer.


Should the Commission decide that glass is no longer waste when prepared for reprocessing, it could mean that PRNs might be issued by recyclers rather than the glassmakers a similar situation to metals recycling. But, it is unclear whether sending the glass to aggregate use will count as being the same as it may be that aggregates producers would still be the ones to issue the PRN or might even lose the ability under the EU rules.

The UK government, through the Department for Environment, Food and Rural Affairs, will be consulting on PRNs this autumn. It has pledged to make decisions by the 2012 Budget, expected in March 2012.

Defra has said it will be looking at increased recycling targets on packaging producers from 2013 to 2017. We will also consult on establishing a sub-target for recycling of glass into remelt applications.

For the glass industry, Rebecca Cocking, recycling manager at the trade association British Glass, told letsrecycle.com: The JRF specification for glass as a remelt product will be very important. What we would like to see is the UKs waste strategy moved forwards and there needs to be swift action and follow-up.

Ms Cocking added that the industry considered it is time for some of the older MRFs to look at moving away from glass and moving away from aggregates as an outlet. She said that with the development of colour sorting equipment, mixed colour can be handled and it may be appropriate to have more frequent bottle banks in some areas, including some installed underground. There are a number of other solutions too that can be looked at for those MRF operators who look to change their kerbside service. Perhaps home shopping vehicles could take glass back.

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